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Sample records for rutheniumii carbonyl complexes

  1. Cyclometallated ruthenium(II) carbonyl complexes with 1 ...

    Indian Academy of Sciences (India)

    The characterization of the complexes having the ... Electronic spectra of the complexes display multiple strong absorptions in the ... Microanalyses (CHN) were performed by using a ..... proton.47,49 Absence of this signal in the spectra of.

  2. New ruthenium(II) carbonyl complexes bearing disulfide Schiff base ligands and their applications as catalyst for some organic transformations

    Science.gov (United States)

    Prakash, Govindan; Viswanathamurthi, Periasamy

    2014-08-01

    Schiff base disulfide ligands (H2L1-6) were synthesized from the condensation of cystamine with salicylaldehyde(H2L1), 5-chlorosalicylaldehyde(H2L2), o-vanillin(H2L3), 2-hydroxyacetophenone(H2L4), 3-methyl-2-hydroxyacetophenone(H2L5), and 2-hydroxy-1-naphthaldehyde(H2L6). H2L1-6 reacts with the ruthenium precursor complex [RuHCl(CO)(PPh3)3] in benzene giving rise to six new ruthenium(II) complexes of general formula [Ru(CO)L1-6]. Characterization of the new complexes was carried out by using elemental and spectral (IR, UV-Vis, NMR (1H and 13C) and Mass) techniques. An octahedral geometry was assigned for all the complexes based on the spectral data obtained. The catalytic efficiency of the new complexes in aldehyde to amide conversion in the presence of NaHCO3, N-alkylation of aniline in the presence of t-BuOK, and transfer hydrogenation of ketones in the presence of iPrOH/KOH reactions were studied. Furthermore, the effect of solvents and catalyst/substrate ratio on the catalytic aldehyde to amide conversion were also discussed.

  3. Ruthenium(II) carbonyl compounds with the 4'-chloro-2,2':6',2''-terpyridine ligand.

    Science.gov (United States)

    Tatikonda, Rajendhraprasad; Haukka, Matti

    2017-04-01

    Two ruthenium carbonyl complexes with the 4'-chloro-2,2':6',2''-terpyridine ligand (tpy-Cl, C 15 H 10 ClN 3 ), i.e. [RuCl(tpy-Cl)(CO) 2 ][RuCl 3 (CO) 3 ] (I) [systematic name: cis -di-carbonyl-chlorido(4'-chloro-2,2':6',2''-terpyridine-κ 3 N )ruthenium(II) fac -tricarbonyltri-chlorido-ruthenate(II)], and [RuCl 2 (tpy-Cl)(CO) 2 ] (II) [ cis -dicarbonyl- trans -di-chlorido(4'-chloro-2,2':6',2''-terpyridine-κ 2 N 1 , N 1' )ruthenium(II)], were synthesized and characterized by single-crystal X-ray diffraction. The Ru II atoms in both centrosymmetric structures (I) and (II) display similar, slightly distorted octa-hedral coordination spheres. The coordination sphere in the complex cation in compound (I) is defined by three N atoms of the tridentate tpy-Cl ligand, two carbonyl carbon atoms and one chlorido ligand; the charge is balanced by an octa-hedral [Ru(CO) 3 Cl 3 ] - counter-anion. In the neutral compound (II), the tpy-Cl ligand coordinates to the metal only through two of its N atoms. The coordination sphere of the Ru II atom is completed by two carbonyl and two chlorido ligands. In the crystal structures of both (I) and (II), weak C-H⋯Cl inter-actions are observed.

  4. Mixed-ligand complexes of ruthenium(II) incorporating a diazo ...

    Indian Academy of Sciences (India)

    Unknown

    Dedicated to the memory of the late Professor Bhaskar G Maiya. *For correspondence. Mixed-ligand complexes of ruthenium(II) incorporating a diazo ligand: Synthesis .... water (1 : 1) for 5 h to give a dark red solution. The solution was cooled to room temperature. After eva- poration of the solvent, the solid was collected,.

  5. Anti-Leishmania activity of new ruthenium(II) complexes: Effect on parasite-host interaction.

    Science.gov (United States)

    Costa, Mônica S; Gonçalves, Yasmim G; Nunes, Débora C O; Napolitano, Danielle R; Maia, Pedro I S; Rodrigues, Renata S; Rodrigues, Veridiana M; Von Poelhsitz, Gustavo; Yoneyama, Kelly A G

    2017-10-01

    Leishmaniasis is a parasitic disease caused by protozoa of the genus Leishmania. The many complications presented by the current treatment - including high toxicity, high cost and parasite resistance - make the development of new therapeutic agents indispensable. The present study aims to evaluate the anti-Leishmania potential of new ruthenium(II) complexes, cis‑[Ru II (η 2 -O 2 CR)(dppm) 2 ]PF 6 , with dppm=bis(diphenylphosphino)methane and R=4-butylbenzoate (bbato) 1, 4-(methylthio)benzoate (mtbato) 2 and 3-hydroxy-4-methoxybenzoate (hmxbato) 3, in promastigote cytotoxicity and their effect on parasite-host interaction. The cytotoxicity of complexes was analyzed by MTT assay against Leishmania (Leishmania) amazonensis, Leishmania (Viannia) braziliensis, Leishmania (Leishmania) infantum promastigotes and the murine macrophage (RAW 264.7). The effect of complexes on parasite-host interaction was evaluated by in vitro infectivity assay performed in the presence of two different concentrations of each complex: the promastigote IC 50 value and the concentration nontoxic to 90% of RAW 264.7 macrophages. Complexes 1-3 exhibited potent cytotoxic activity against all Leishmania species assayed. The IC 50 values ranged from 7.52-12.59μM (complex 1); 0.70-3.28μM (complex 2) and 0.52-1.75μM (complex 3). All complexes significantly inhibited the infectivity index at both tested concentrations. The infectivity inhibitions ranged from 37 to 85%. Interestingly, the infectivity inhibitions due to complex action did not differ significantly at either of the tested concentrations, except for the complex 1 against Leishmania (Leishmania) infantum. The infectivity inhibitions resulted from reductions in both percentage of infected macrophages and number of parasites per macrophage. Taken together the results suggest remarkable leishmanicidal activity in vitro by these new ruthenium(II) complexes. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Synthesis and Catalytic Hydrogen Transfer Reaction of Ruthenium(II) Complex

    International Nuclear Information System (INIS)

    Son, Jung Ik; Kim, Aram; Noh, Hui Bog; Lee, Hyun Ju; Shim, Yoon Bo; Park, Kang Hyun

    2012-01-01

    The ruthenium(II) complex [Ru(bpy) 2 -(PhenTPy)] was synthesized, and used for the transfer hydrogenation of ketones and the desired products were obtained in good yield. Based on the presented results, transition-metal complexes can be used as catalysts for a wide range of organic transformations. The relationship between the electro-reduction current density and temperature are being examined in this laboratory. Attempts to improve the catalytic activity and determine the transfer hydrogenation mechanism are currently in progress. The catalytic hydrogenation of a ketone is a basic and critical process for making many types of alcohols used as the final products and precursors in the pharmaceutical, agrochemical, flavor, fragrance, materials, and fine chemicals industries. The catalytic hydrogenation process developed by Noyori is a very attractive process. Formic acid and 2-propanol have been used extensively as hydrogenation sources. The advantage of using 2-propanol as a hydrogen source is that the only side product will be acetone, which can be removed easily during the workup process. Hydrogen transfer (HT) catalysis, which generates alcohols through the reduction of ketones, is an attractive protocol that is used widely. Ruthenium(II) complexes are the most useful catalysts for the hydrogen transfer (HT) of ketones. In this method, a highly active catalytic system employs a transition metal as a catalyst to synthesize alcohols, and is a replacement for the hydrogen-using hydrogenation process. The most active system is based on Ru, Rh and Ir, which includes a nitrogen ligand that facilitates the formation of a catalytically active hydride and phosphorus

  7. Synthesis and Catalytic Hydrogen Transfer Reaction of Ruthenium(II) Complex

    Energy Technology Data Exchange (ETDEWEB)

    Son, Jung Ik; Kim, Aram; Noh, Hui Bog; Lee, Hyun Ju; Shim, Yoon Bo; Park, Kang Hyun [Pusan National University, Busan (Korea, Republic of)

    2012-01-15

    The ruthenium(II) complex [Ru(bpy){sub 2}-(PhenTPy)] was synthesized, and used for the transfer hydrogenation of ketones and the desired products were obtained in good yield. Based on the presented results, transition-metal complexes can be used as catalysts for a wide range of organic transformations. The relationship between the electro-reduction current density and temperature are being examined in this laboratory. Attempts to improve the catalytic activity and determine the transfer hydrogenation mechanism are currently in progress. The catalytic hydrogenation of a ketone is a basic and critical process for making many types of alcohols used as the final products and precursors in the pharmaceutical, agrochemical, flavor, fragrance, materials, and fine chemicals industries. The catalytic hydrogenation process developed by Noyori is a very attractive process. Formic acid and 2-propanol have been used extensively as hydrogenation sources. The advantage of using 2-propanol as a hydrogen source is that the only side product will be acetone, which can be removed easily during the workup process. Hydrogen transfer (HT) catalysis, which generates alcohols through the reduction of ketones, is an attractive protocol that is used widely. Ruthenium(II) complexes are the most useful catalysts for the hydrogen transfer (HT) of ketones. In this method, a highly active catalytic system employs a transition metal as a catalyst to synthesize alcohols, and is a replacement for the hydrogen-using hydrogenation process. The most active system is based on Ru, Rh and Ir, which includes a nitrogen ligand that facilitates the formation of a catalytically active hydride and phosphorus.

  8. DNA interaction, antioxidant activity, and bioactivity studies of two ruthenium(II) complexes

    Science.gov (United States)

    Han, Bing-Jie; Jiang, Guang-Bin; Yao, Jun-Hua; Li, Wei; Wang, Ji; Huang, Hong-Liang; Liu, Yun-Jun

    2015-01-01

    Two new ruthenium(II) polypyridyl complexes [Ru(dmb)2(dcdppz)](ClO4)2 (1) and [Ru(bpy)2(dcdppz)](ClO4)2 (2) were prepared and characterized. The crystal structure of the complex 2 was solved by single crystal X-ray diffraction. The complex crystallizes in the monoclinic system, space group P21/n with a = 12.9622(14) Å, b = 17.1619(19) Å, c = 22.7210(3) Å, β = 100.930(2)°, R = 0.0536, Rω = 0.1111. The DNA-binding constants for complexes 1 and 2 were determined to be 1.92 × 105 (s = 1.72) and 2.24 × 105 (s = 1.86) M-1, respectively. The DNA-binding behaviors showed that complexes 1 and 2 interact with DNA by intercalative mode. The antioxidant activities of the ligand and the complexes were performed. Ligand, dcdppz, has no cytotoxicity against the selected cell lines. Complex 1 shows higher cytotoxicity than complex 2, but lower than cisplatin toward selected cell lines. The apoptosis and cell cycle arrest were investigated, and the apoptotic mechanism of BEL-7402 cells was studied by reactive oxygen species (ROS), mitochondrial membrane potential and western blot analysis. Complex 1 induces apoptosis in BEL-7402 cells through ROS-mediated mitochondrial dysfunction pathway and by regulating the expression of Bcl-2 family proteins.

  9. Spectral sensitization of SrTiO3 photoanodes with binuclear 1,10-phenanthroline bis(2,2'-bipyridine) complexes of ruthenium(II) and tris(2,2'-bipyridine) ruthenium(II)

    NARCIS (Netherlands)

    Tinnemans, A.H.A.; Mackor, A.

    1981-01-01

    A single crystal of strontium titanate, used as a photoanode for the photoelectrolysis of water, has been sensitized by mono‐ and binuclear ruthenium(II) complexes in acidic solution for visible light. The dependence of the photocurrent density on light intensity, dye concentration, wavelength and

  10. Cyclometalated Ruthenium(II) Anthraquinone Complexes Exhibit Strong Anticancer Activity in Hypoxic Tumor Cells.

    Science.gov (United States)

    Zeng, Leli; Chen, Yu; Huang, Huaiyi; Wang, Jinquan; Zhao, Donglei; Ji, Liangnian; Chao, Hui

    2015-10-19

    Hypoxia is the critical feature of the tumor microenvironment that is known to lead to resistance to many chemotherapeutic drugs. Six novel ruthenium(II) anthraquinone complexes were designed and synthesized; they exhibit similar or superior cytotoxicity compared to cisplatin in hypoxic HeLa, A549, and multidrug-resistant (A549R) tumor cell lines. Their anticancer activities are related to their lipophilicity and cellular uptake; therefore, these physicochemical properties of the complexes can be changed by modifying the ligands to obtain better anticancer candidates. Complex 1, the most potent member of the series, is highly active against hypoxic HeLa cancer cells (IC50 =0.53 μM). This complex likely has 46-fold better activity than cisplatin (IC50 =24.62 μM) in HeLa cells. This complex tends to accumulate in the mitochondria and the nucleus of hypoxic HeLa cells. Further mechanistic studies show that complex 1 induced cell apoptosis during hypoxia through multiple pathways, including those of DNA damage, mitochondrial dysfunction, and the inhibition of DNA replication and HIF-1α expression, making it an outstanding candidate for further in vivo studies. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Ultrafast relaxation dynamics of amine-substituted bipyridyl ruthenium(II) complexes

    Science.gov (United States)

    Song, Hongwei; Wang, Xian; Yang, WenWen; He, Guiying; Kuang, Zhuoran; Li, Yang; Xia, Andong; Zhong, Yu-Wu; Kong, Fan'ao

    2017-09-01

    The excited state properties of a series of ruthenium(II) amine-substituted bipyridyl complexes, [Ru(bpy)n(NNbpy)3-n]2+, were investigated by steady-state and transient absorption spectroscopy, as well as quantum chemical calculations. The steady-state absorption spectra of these complexes in CH3CN show a distinct red-shift of the 1MLCT absorption with increasing numbers of amine substituent, whereas the emission spectra indicate an energy gap order of [Ru(bpy)3]2+ > [Ru(bpy)2(NNbpy)]2+ > [Ru(NNbpy)3]2+ > [Ru(bpy)(NNbpy)2]2+. Nanosecond, femtosecond transient absorption and electrochemical measurements suggest that NNbpy ligand has a strong influence on the electronic and emission properties of these complexes, due to electron-rich amine substituent. We illustrate how the numbers of amine substituent modulate the spectroscopic properties of transition metal complexes, which is related to the design of new electro-active systems with novel photoelectrochemical properties.

  12. Synthesis, structure, DNA binding and anticancer activity of mixed ligand ruthenium(II) complex

    Science.gov (United States)

    Gilewska, Agnieszka; Masternak, Joanna; Kazimierczuk, Katarzyna; Trynda, Justyna; Wietrzyk, Joanna; Barszcz, Barbara

    2018-03-01

    In order to obtain a potential chemotherapeutic which is not affected on the normal BALB/3T3 cell line, a new arene ruthenium(II) complex {[RuCl(L1)(η6-p-cymene)]PF6}2 · H2O has been synthesized by a direct reaction of precursor, [{(η6-p-cymene)Ru(μ-Cl)}2Cl2], with N,N-chelating ligand (L1 - 2,2‧-bis(4,5-dimethylimidazole). The compound has been fully characterized by elemental analysis, X-ray diffraction, IR, UV-Vis and 1H, 13C NMR spectroscopies. X-ray analysis have confirmed that the compound crystallized in the monoclinic group Cc as an inversion twin. The asymmetric unit contains two symmetrically independent cationic complexes [RuCl(L1)(η6-p-cymene)]+ whose charge is balanced by two PF6- counterions. The shape of each cationic coordination polyhedral can be described as a distorted dodecahedron and shows a typical piano-stool geometry. In addition, an analysis of the crystal structure and the Hirshfeld surface analysis were used to detect and visualize important hydrogen bonds and intermolecular interaction. Moreover, the antiproliferative behavior of the obtained complex was assayed against three human cells: MV-4-11, LoVo, MCF-7 and BALB/3T3 - normal mice fibroblast cells. To predict a binding mode, a potential interaction of ruthenium complex with calf thymus DNA (CT-DNA) has been explored using UV absorption and circular dichroism (CD).

  13. Synthesis and characterization of new mixed ligand complexes of ruthenium(II) containing triphenylphosphine and 2'-hydroxychalcones

    International Nuclear Information System (INIS)

    Dharmaraj, N.; Natarajan, K.

    1994-01-01

    A few hexacoordinated ruthenium(II) complexes of the type [RuCl(CO) (HLL')(PPh 3 ) 2 ] and [RuCl(CO)(HLL')(B) (PPh 3 )] (where HLL' 2'-hydroxychalcone, 2'-hydroxy-4-methoxychalcone, 2'-hydroxy-3,4-dimethoxychalcone and B=pyridine(Py), piperidine(Pip), morpholine (Morph)) have been synthesised and characterized on the basis of their analytical and spectral data (IR, electronic and 1 H NMR). In all these complexes, the 2'-hydroxychalcones behave as a uninegative bidentate (OO - ) chelating ligand. (author). 17 refs., 1 tab

  14. A High Molar Extinction Coefficient Mono-Anthracenyl Bipyridyl Heteroleptic Ruthenium(II Complex: Synthesis, Photophysical and Electrochemical Properties

    Directory of Open Access Journals (Sweden)

    Peter A. Ajibade

    2011-06-01

    Full Text Available In our quest to develop good materials as photosensitizers for photovoltaic dye-sensitized solar cells (DSSCs, cis-dithiocyanato-4-(2,3-dimethylacrylic acid-2,2'-bipyridyl-4-(9-anthracenyl-(2,3-dimethylacrylic-2,2'-bipyridyl ruthenium(II complex, a high molar extinction coefficient charge transfer sensitizer, was designed, synthesized and characterized by spectroscopy and electrochemical techniques. Earlier studies on heteroleptic ruthenium(II complex analogues containing functionalized oligo-anthracenyl phenanthroline ligands have been reported and documented. Based on a general linear correlation between increase in the length of π-conjugation bond and the molar extinction coefficients, herein, we report the photophysical and electrochemical properties of a Ru(II bipyridyl complex analogue with a single functionalized anthracenyl unit. Interestingly, the complex shows better broad and intense metal-to ligand charge transfer (MLCT band absorption with higher molar extinction coefficient (λmax = 518 nm, e = 44900 M−1cm−1, and appreciable photoluminescence spanning the visible region than those containing higher anthracenyl units. It was shown that molar absorption coefficient of the complexes may not be solely depended on the extended π-conjugation but are reduced by molecular aggregation in the molecules.

  15. Mitochondria are the primary target in the induction of apoptosis by chiral ruthenium(II) polypyridyl complexes in cancer cells.

    Science.gov (United States)

    Wang, Jin-Quan; Zhang, Ping-Yu; Qian, Chen; Hou, Xiao-Juan; Ji, Liang-Nian; Chao, Hui

    2014-03-01

    A series of novel chiral ruthenium(II) polypyridyl complexes (Δ-Ru1, Λ-Ru1, Δ-Ru2, Λ-Ru2, Δ-Ru3, Λ-Ru3) were synthesized and evaluated to determine their antiproliferative activities. Colocalization, inductively coupled plasma mass spectrometry, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay studies showed that these ruthenium(II) complexes accumulated preferentially in the mitochondria and exhibited cytotoxicity against various cancer cells in vitro. The complex Δ-Ru1 is of particular interest because it was found to have half-maximal inhibitory concentrations comparable to those of cisplatin and better activity than cisplatin against a cisplatin-resistant cell line, A549-CP/R. Δ-Ru1 induced alterations in the mitochondrial membrane potential and triggered intrinsic mitochondria-mediated apoptosis in HeLa cells, which involved the regulation of Bcl-2 family members and the activation of caspases. Taken together, these data suggest that Δ-Ru1 may be a novel mitochondria-targeting anticancer agent.

  16. Ruthenium(II carbonyl compounds with the 4′-chloro-2,2′:6′,2′′-terpyridine ligand

    Directory of Open Access Journals (Sweden)

    Rajendhraprasad Tatikonda

    2017-04-01

    Full Text Available Two ruthenium carbonyl complexes with the 4′-chloro-2,2′:6′,2′′-terpyridine ligand (tpy-Cl, C15H10ClN3, i.e. [RuCl(tpy-Cl(CO2][RuCl3(CO3] (I [systematic name: cis-dicarbonylchlorido(4′-chloro-2,2′:6′,2′′-terpyridine-κ3Nruthenium(II fac-tricarbonyltrichloridoruthenate(II], and [RuCl2(tpy-Cl(CO2] (II [cis-dicarbonyl-trans-dichlorido(4′-chloro-2,2′:6′,2′′-terpyridine-κ2N1,N1′ruthenium(II], were synthesized and characterized by single-crystal X-ray diffraction. The RuII atoms in both centrosymmetric structures (I and (II display similar, slightly distorted octahedral coordination spheres. The coordination sphere in the complex cation in compound (I is defined by three N atoms of the tridentate tpy-Cl ligand, two carbonyl carbon atoms and one chlorido ligand; the charge is balanced by an octahedral [Ru(CO3Cl3]− counter-anion. In the neutral compound (II, the tpy-Cl ligand coordinates to the metal only through two of its N atoms. The coordination sphere of the RuII atom is completed by two carbonyl and two chlorido ligands. In the crystal structures of both (I and (II, weak C—H...Cl interactions are observed.

  17. Carbonyl complexes of rhodium with N-donor ligands: factors determining the formation of terminal versus bridging carbonyls

    NARCIS (Netherlands)

    Dzik, W.I.; Creusen, C.; de Gelder, R.; Peters, T.P.J.; Smits, J.M.M.; de Bruin, B.

    2010-01-01

    Cationic rhodium carbonyl complexes supported by a series of different N-3- and N-4-donor ligands were prepared, and their ability to form carbonyl-bridged species was evaluated. Complex [Rh(K3-bpa)(cod)r (1(+)) (bpa = bis(2-picolyBamine, cod = cis,cis-1,5-cyclooctadiene) reacts with I bar of CO to

  18. Electrochemical DNA biosensor for detection of porcine oligonucleotides using ruthenium(II) complex as intercalator label redox

    Energy Technology Data Exchange (ETDEWEB)

    Halid, Nurul Izni Abdullah; Hasbullah, Siti Aishah; Heng, Lee Yook; Karim, Nurul Huda Abd [School of Chemical Sciences and Food Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan (Malaysia); Ahmad, Haslina; Harun, Siti Norain [Chemistry Department, Faculty of Science, Universiti Putra Malaysia, 43400, Serdang, Selangor (Malaysia)

    2014-09-03

    A DNA biosensor detection of oligonucleotides via the interactions of porcine DNA with redox active complex based on the electrochemical transduction is described. A ruthenium(II) complex, [Ru(bpy){sub 2}(PIP)]{sup 2+}, (bpy = 2,2′bipyridine, PIP = 2-phenylimidazo[4,5-f[[1,10-phenanthroline]) as DNA label has been synthesized and characterized by 1H NMR and mass spectra. The study was carried out by covalent bonding immobilization of porcine aminated DNA probes sequences on screen printed electrode (SPE) modified with succinimide-acrylic microspheres and [Ru(bpy){sub 2}(PIP)]{sup 2+} was used as electrochemical redox intercalator label to detect DNA hybridization event. Electrochemical detection was performed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) over the potential range where the ruthenium (II) complex was active. The results indicate that the interaction of [Ru(bpy){sub 2}(PIP)]{sup 2+} with hybridization complementary DNA has higher response compared to single-stranded and mismatch complementary DNA.

  19. A ruthenium(II) complex inhibits tumor growth in vivo with fewer side-effects compared with cisplatin.

    Science.gov (United States)

    Wang, Jin-Quan; Zhang, Ping-Yu; Ji, Liang-Nian; Chao, Hui

    2015-05-01

    The antitumor activity of a ruthenium(II) polypyridyl complex, Δ-[Ru(bpy)2(HPIP)](ClO4)2 (Δ-Ru1, where bpy=2,2'-bipyridine, HPIP=2-(2-hydroxyphenyl)imidazo[4,5-f][1,10]phenanthroline), was evaluated. The in vivo experiments showed that Δ-Ru1 inhibited the growth of a human cervical carcinoma cell line (HeLa) xenotransplanted into nude mice with efficiency similar to that of cisplatin. Histopathology examination of the tumors from treated xenograft models was consistent with apoptosis in tumor cells. Importantly, in striking contrast with cisplatin, Δ-Ru1 did not cause any detectable side effects on the kidney, liver, peripheral neuronal system, or the hematological system at the pharmacologically effective dose. The preclinical studies reported here provide support for the clinical use of Δ-Ru1 as an exciting new drug candidate with lower toxicity than cisplatin, endowed with proapoptotic properties. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Ruthenium(II) 2,2'-bibenzimidazole complex as a second-sphere receptor for anions interaction and colorimeter.

    Science.gov (United States)

    Cui, Ying; Niu, Yan-Li; Cao, Man-Li; Wang, Ke; Mo, Hao-Jun; Zhong, Yong-Rui; Ye, Bao-Hui

    2008-07-07

    A ruthenium(II) complex [Ru(bpy) 2(H 2bbim)](PF 6) 2 ( 1) as anions receptor has been exploited, where Ru(II)-bpy moiety acts as a chromophore and the H 2bbim ligand as an anion binding site. A systematic study suggests that 1 interacts with the Cl (-), Br (-), I (-), NO 3 (-), HSO 4 (-), and H 2PO 4 (-) anions via the formation of hydrogen bonds. Whereas 1 undergoes a stepwise process with the addition of F (-) and OAc (-) anions: formation of the monodeprotonated complex [Ru(bpy) 2(Hbbim)] with a low anion concentration, followed by the double-deprotonated complex [Ru(bpy) 2(bbim)], in the presence of a high anion concentration. These stepwise processes concomitant with the changes of vivid colors from yellow to orange brown and then to violet can be used for probing the F (-) and OAc (-) anions by naked eye. The deprotonation processes are not only determined by the basicity of the anion but also related to the strength of hydrogen bonding, as well as the stability of the formed compounds. Moreover, a double-deprotonated complex [Ru(bpy) 2(bbim)].CH 3OH.H 2O ( 3) has been synthesized, and the structural changes induced by the deprotonation has also been investigated. In addition, complexes [Ru(bpy) 2(Hbbim)] 2(HOAc) 3Cl 2.12H 2O ( 2), [Ru(bpy) 2(Hbbim)](HCCl 3CO 2)(CCl 3CO 2).2H 2O ( 4), and [Ru(bpy) 2(H 2bbim)](CF 3CO 2) 2.4H 2O ( 5) have been synthesized to observe the second sphere coordination between the Ru(II)-H 2bbim moiety and carboxylate groups via hydrogen bonds in the solid state.

  1. Synthesis and properties of mixed-ligand ruthenium(II) complexes containing 2-(2-pyridyl)-benzimidazole and related ligands

    Energy Technology Data Exchange (ETDEWEB)

    Haga, M [Mie Univ., Tsu (Japan); Tanaka, T

    1979-07-01

    Mixed-ligand ruthenium(II) complexes of the (Ru(bpy)/sub 2/L)sup(n+) (ClO/sub 4/)sub(n) type, where bpy= 2,2'-bipyridine; L= 2-(2-pyridyl)-benzimidazole (PBImH) when n= 2, and L= 2-(2-pyridyl)-benzimidazolate (PBIm) and 2-(o-hydroxyphenyl)-benzimidazole (OBImH) when n= 1, were prepared. Anodic peak potentials and ruthenium-to-bipyridine charge transfer bands of these complexes are rationalized in terms of the donor ability of L.

  2. Synthesis and properties of mixed-ligand ruthenium(II) complexes containing 2-(2-pyridyl)-benzimidazole and related ligands

    International Nuclear Information System (INIS)

    Haga, Masaaki; Tanaka, Toshio.

    1979-01-01

    Mixed-ligand ruthenium(II) complexes of the [Ru(bpy) 2 L]sup(n+) (ClO 4 )sub(n) type, where bpy= 2,2'-bipyridine; L= 2-(2-pyridyl)-benzimidazole (PBImH) when n= 2, and L= 2-(2-pyridyl)-benzimidazolate (PBIm) and 2-(o-hydroxyphenyl)-benzimidazole (OBImH) when n= 1, were prepared. Anodic peak potentials and ruthenium-to-bipyridine charge transfer bands of these complexes are rationalized in terms of the donor ability of L. (author)

  3. Pharmacophore Modelling and 4D-QSAR Study of Ruthenium(II) Arene Complexes as Anticancer Agents (Inhibitors) by Electron Conformational- Genetic Algorithm Method.

    Science.gov (United States)

    Yavuz, Sevtap Caglar; Sabanci, Nazmiye; Saripinar, Emin

    2018-01-01

    The EC-GA method was employed in this study as a 4D-QSAR method, for the identification of the pharmacophore (Pha) of ruthenium(II) arene complex derivatives and quantitative prediction of activity. The arrangement of the computed geometric and electronic parameters for atoms and bonds of each compound occurring in a matrix is known as the electron-conformational matrix of congruity (ECMC). It contains the data from HF/3-21G level calculations. Compounds were represented by a group of conformers for each compound rather than a single conformation, known as fourth dimension to generate the model. ECMCs were compared within a certain range of tolerance values by using the EMRE program and the responsible pharmacophore group for ruthenium(II) arene complex derivatives was found. For selecting the sub-parameter which had the most effect on activity in the series and the calculation of theoretical activity values, the non-linear least square method and genetic algorithm which are included in the EMRE program were used. In addition, compounds were classified as the training and test set and the accuracy of the models was tested by cross-validation statistically. The model for training and test sets attained by the optimum 10 parameters gave highly satisfactory results with R2 training= 0.817, q 2=0.718 and SEtraining=0.066, q2 ext1 = 0.867, q2 ext2 = 0.849, q2 ext3 =0.895, ccctr = 0.895, ccctest = 0.930 and cccall = 0.905. Since there is no 4D-QSAR research on metal based organic complexes in the literature, this study is original and gives a powerful tool to the design of novel and selective ruthenium(II) arene complexes. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  4. Synthesis, DNA Cleavage Activity, Cytotoxicity, Acetylcholinesterase Inhibition, and Acute Murine Toxicity of Redox-Active Ruthenium(II) Polypyridyl Complexes.

    Science.gov (United States)

    Alatrash, Nagham; Narh, Eugenia S; Yadav, Abhishek; Kim, Mahn-Jong; Janaratne, Thamara; Gabriel, James; MacDonnell, Frederick M

    2017-07-06

    Four mononuclear [(L-L) 2 Ru(tatpp)] 2+ and two dinuclear [(L-L) 2 Ru(tatpp)Ru(L-L) 2 ] 4+ ruthenium(II) polypyridyl complexes (RPCs) containing the 9,11,20,22-tetraazatetrapyrido[3,2-a:2',3'-c:3'',2''-l:2''',3'''-n]pentacene (tatpp) ligand were synthesized, in which L-L is a chelating diamine ligand such as 2,2'-bipyridine (bpy), 1,10-phenanthroline (phen), 3,4,7,8-tetramethyl-1,10-phenanthroline (Me 4 phen) or 4,7-diphenyl-1,10-phenanthroline (Ph 2 phen). These Ru-tatpp analogues all undergo reduction reactions with modest reducing agents, such as glutathione (GSH), at pH 7. These, plus several structurally related but non-redox-active RPCs, were screened for DNA cleavage activity, cytotoxicity, acetylcholinesterase (AChE) inhibition, and acute mouse toxicity, and their activities were examined with respect to redox activity and lipophilicity. All of the redox-active RPCs show single-strand DNA cleavage in the presence of GSH, whereas none of the non-redox-active RPCs do. Low-micromolar cytotoxicity (IC 50 ) against malignant H358, CCL228, and MCF7 cultured cell lines was mainly restricted to the redox-active RPCs; however, they were substantially less toxic toward nonmalignant MCF10 cells. The IC 50 values for AChE inhibition in cell-free assays and the acute toxicity of RPCs in mice revealed that whereas most RPCs show potent inhibitory action against AChE (IC 50 values <15 μm), Ru-tatpp complexes as a class are surprisingly well tolerated in animals relative to other RPCs. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Reactivity studies of eta sup (6)-p-cymene ruthenium(II) carboxylato complexes towards azide some neutral ligands

    Digital Repository Service at National Institute of Oceanography (India)

    Singh, K.S.; Kollipara, M.R.

    sub (2)O sub (4)(7) or C sub (2)CH sub (2)O sub (4)(10)] have been prepared by the reaction of [(p-cymene)RuCl sub (2)]sub (2) with the corresponding sodium salts of the carboxylic acids. Treatment of (eta sup (6)-p-cymene) ruthenium(II) carboxylato...

  6. Kinetic effects of sulfur oxidation on catalytic nitrile hydration: nitrile hydratase insights from bioinspired ruthenium(II) complexes.

    Science.gov (United States)

    Kumar, Davinder; Nguyen, Tho N; Grapperhaus, Craig A

    2014-12-01

    Kinetic investigations inspired by the metalloenzyme nitrile hydratase were performed on a series of ruthenium(II) complexes to determine the effect of sulfur oxidation on catalytic nitrile hydration. The rate of benzonitrile hydration was quantified as a function of catalyst, nitrile, and water concentrations. Precatalysts L(n)RuPPh3 (n = 1-3; L(1) = 4,7-bis(2'-methyl-2'-mercapto-propyl)-1-thia-4,7-diazacyclononane; L(2) = 4-(2'-methyl-2'-sulfinatopropyl)-7-(2'-methyl-2'-mercapto-propyl)-1-thia-4,7-diazacyclononane; L(3) = 4-(2'-methyl-2'-sulfinatopropyl)-7-(2'-methyl-2'-sulfenato-propyl)-1-thia-4,7-diazacyclononane) were activated by substitution of triphenylphosphine with substrate in hot dimethylformamide solution. Rate measurements are consistent with a dynamic equilibrium between inactive aqua (L(n)Ru-OH2) and active nitrile (L(n)Ru-NCR) derivatives with K = 21 ± 1, 9 ± 0.9, and 23 ± 3 for L(1) to L(3), respectively. Subsequent hydration of the L(n)Ru-NCR intermediate yields the amide product with measured hydration rate constants (k's) of 0.37 ± 0.01, 0.82 ± 0.07, and 1.59 ± 0.12 M(-1) h(-1) for L(1) to L(3), respectively. Temperature dependent studies reveal that sulfur oxidation lowers the enthalpic barrier by 27 kJ/mol, but increases the entropic barrier by 65 J/(mol K). Density functional theory (DFT) calculations (B3LYP/LanL2DZ (Ru); 6-31G(d) (all other atoms)) support a nitrile bound catalytic cycle with lowering of the reaction barrier as a consequence of sulfur oxidation through enhanced nitrile binding and attack of the water nucleophile through a highly organized transition state.

  7. Evaluation of DNA binding, DNA cleavage, protein binding, radical scavenging and in vitro cytotoxic activities of ruthenium(II) complexes containing 2,4-dihydroxy benzylidene ligands

    Energy Technology Data Exchange (ETDEWEB)

    Mohanraj, Maruthachalam; Ayyannan, Ganesan; Raja, Gunasekaran; Jayabalakrishnan, Chinnasamy, E-mail: drcjbstar@gmail.com

    2016-12-01

    The new ruthenium(II) complexes with hydrazone ligands, 4-Methyl-benzoic acid (2,4-dihydroxy-benzylidene)-hydrazide (HL{sup 1}), 4-Methoxy-benzoic acid (2,4-dihydroxy-benzylidene)-hydrazide (HL{sup 2}), 4-Bromo-benzoic acid (2,4-dihydroxy-benzylidene)-hydrazide (HL{sup 3}), were synthesized and characterized by various spectro analytical techniques. The molecular structures of the ligands were confirmed by single crystal X-ray diffraction technique. The DNA binding studies of the ligands and complexes were examined by absorption, fluorescence, viscosity and cyclic voltammetry methods. The results indicated that the ligands and complexes could interact with calf thymus DNA (CT-DNA) through intercalation. The DNA cleavage activity of the complexes was evaluated by gel electrophoresis assay, which revealed that the complexes are good DNA cleaving agents. The binding interaction of the ligands and complexes with bovine serum albumin (BSA) was investigated using fluorescence spectroscopic method. Antioxidant studies showed that the complexes have a strong radical scavenging properties. Further, the cytotoxic effect of the complexes examined on cancerous cell lines showed that the complexes exhibit significant anticancer activity. - Highlights: • Synthesis of ruthenium(II) hydrazone complexes • Molecular structure of the ligands was elucidated by single crystal X-ray diffraction method. • The ligands and complexes interact with CT-DNA via intercalation. • The complexes possess significant antioxidant activity against DPPH, OH and NO radicals. • The complex 6 shows higher IC{sub 50} value than the other complexes against cancer cells.

  8. Impact of aromaticity on anticancer activity of polypyridyl ruthenium(II) complexes: synthesis, structure, DNA/protein binding, lipophilicity and anticancer activity.

    Science.gov (United States)

    Čanović, Petar; Simović, Ana Rilak; Radisavljević, Snežana; Bratsos, Ioannis; Demitri, Nicola; Mitrović, Marina; Zelen, Ivanka; Bugarčić, Živadin D

    2017-10-01

    With the aim of assessing how the aromaticity of the inert chelating ligand can influence the activity of ruthenium(II) polypyridyl complexes, two new monofunctional ruthenium(II) complexes, [Ru(Cl-Ph-tpy)(phen)Cl]Cl (1) and [Ru(Cl-Ph-tpy)(o-bqdi)Cl]Cl (2) (where Cl-Ph-tpy = 4'-(4-chlorophenyl)-2,2':6',2″-terpyridine, phen = 1,10-phenanthroline, o-bqdi = o-benzoquinonediimine), were synthesized. All complexes were fully characterized by elemental analysis and spectroscopic techniques (IR, UV-Vis, 1D and 2D NMR, XRD). Their chemical behavior in aqueous solution was studied by UV-Vis and NMR spectroscopy showing that both compounds are relatively labile leading to the formation of the corresponding aqua species 1a and 2a. 1 H NMR spectroscopy studies performed on complexes 1 and 2 demonstrated that after the hydrolysis of the Cl ligand, they are capable to interact with guanine derivatives (i.e., 9-methylguanine (9MeG) and 5'-GMP) through the N7, forming monofunctional adduct. The kinetics and the mechanism of the reaction of complexes 1 and 2 with the biologically more relevant 5'-GMP ligand were studied by UV-Vis spectroscopy. DNA/protein interactions of the complexes have been examined by photophysical studies, which demonstrated a bifunctional binding mode of the complexes with DNA and the complexes strongly quench the fluorescence intensity of bovine serum albumin (BSA) through the mechanism of both static and dynamic quenching. Complexes 1 and 2 strongly induced apoptosis of treated cancer cells with high percentages of apoptotic cells and negligible percentage of necrotic cells. In addition, both ruthenium complexes decreased Bcl-2/Bax ratio causing cytochrome c mitochondrial release, the activation of caspase-3 and induction of apoptosis.

  9. Catalytic water oxidation by ruthenium(II) quaterpyridine (qpy) complexes: evidence for ruthenium(III) qpy-N,N'''-dioxide as the real catalysts.

    Science.gov (United States)

    Liu, Yingying; Ng, Siu-Mui; Yiu, Shek-Man; Lam, William W Y; Wei, Xi-Guang; Lau, Kai-Chung; Lau, Tai-Chu

    2014-12-22

    Polypyridyl and related ligands have been widely used for the development of water oxidation catalysts. Supposedly these ligands are oxidation-resistant and can stabilize high-oxidation-state intermediates. In this work a series of ruthenium(II) complexes [Ru(qpy)(L)2 ](2+) (qpy=2,2':6',2'':6'',2'''-quaterpyridine; L=substituted pyridine) have been synthesized and found to catalyze Ce(IV) -driven water oxidation, with turnover numbers of up to 2100. However, these ruthenium complexes are found to function only as precatalysts; first, they have to be oxidized to the qpy-N,N'''-dioxide (ONNO) complexes [Ru(ONNO)(L)2 ](3+) which are the real catalysts for water oxidation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Photoreactions of ruthenium(II) and osmium(II) complexes with deoxyribonucleic acid (DNA).

    Science.gov (United States)

    Moucheron, C; Kirsch-De Mesmaeker, A; Kelly, J M

    1997-09-01

    The design of Ru(II) and Os(II) complexes which are photoreactive with deoxyribonucleic acid (DNA) represents one of the main targets for the development of novel molecular tools for the study of DNA and, in the future, for the production of new, metal-based, anti-tumor drugs. In this review, we explain how it is possible to make a complex photoreactive with nucleobases and nucleic acids. According to the photophysical behaviour of the Ru(II) compounds, two types of photochemistry are expected: (1) photosubstitution of a ligand by a nucleobase and another monodentate ligand, which takes place from the triplet, metal-centred (3MC) state; this state is populated thermally from the lowest lying triplet metal to ligand charge transfer (3MLCT) state; (2) photoreaction from the 3MLCT state, corresponding to photoredox processes with DNA bases. The two photoreactivities are in competition. By modulating appropriately the redox properties of the 3MLCT state, an electron transfer process from the base to the excited complex takes place, and is directly correlated with DNA cleavage or the formation of an adduct of the complex to DNA. In this adduct, guanine is linked by N2 to the alpha-position of a non-chelating nitrogen of the polyazaaromatic ligand without destruction of the complex. Different strategies are explained which increase the affinity of the complexes for DNA and direct the complex photoreactivity to sites of special DNA topology or targeted sequences of bases. Moreover, the replacement of the Ru(II) ion by the Os(II) ion in the photoreactive complexes leads to an increased specificity of photoreaction. Indeed, only one type of photoreactivity (from the 3MLCT state) is present for the Os(II) complexes because the 3MC state is too high in energy to be populated at room temperature.

  11. Ruthenium(II) pincer complexes with oxazoline arms for efficient transfer hydrogenation reactions

    KAUST Repository

    Chen, Tao

    2012-08-01

    Well-defined P NN CN pincer ruthenium complexes bearing both strong phosphine and weak oxazoline donors were developed. These easily accessible complexes exhibit significantly better catalytic activity in transfer hydrogenation of ketones compared to their PN 3P analogs. These reactions proceed under mild and base-free conditions via protonation- deprotonation of the \\'NH\\' group in the aromatization-dearomatization process. © 2012 Elsevier Ltd. All rights reserved.

  12. Electron transfer reactions of ruthenium(II) complexes with polyphenolic acids in micelles

    Energy Technology Data Exchange (ETDEWEB)

    Rajeswari, Angusamy [School of Chemistry, Madurai Kamaraj University, Madurai 625 021 (India); Department of Chemistry, Fatima College, Madurai 625 018 (India); Ramdass, Arumugam [School of Chemistry, Madurai Kamaraj University, Madurai 625 021 (India); Research Department of Chemistry, Aditanar College of Arts and Science, Tiruchendur 628 216 (India); Muthu Mareeswaran, Paulpandian [School of Chemistry, Madurai Kamaraj University, Madurai 625 021 (India); Department of Industrial Chemistry, Alagappa University, Karaikudi 630 003 (India); Rajagopal, Seenivasan, E-mail: rajagopalseenivasan@yahoo.com [School of Chemistry, Madurai Kamaraj University, Madurai 625 021 (India)

    2016-02-15

    The electron transfer in a microhetrogeneous system is a perfect mimic of biological electron transfer. The electron transfer between biologically important phenolic acids and ruthenium (II) complexes is systematically studied in the presence of anionic and cationic micelles. The photophysical properties of these ruthenium (II) complexes with anionic and cationic micelles and their binding abilities with these two type of micelles are also studies using absorption, emission and excited state lifetime spectral techniques. Pseudophase Ion Exchange (PIE) Model is applied to derive mechanism of electron transfer in two types of micelles. - Highlights: • Effect of microhetrogeneous system is studied using ruthenium (II) complexes and gallic acid is studied. • Pseudophase Ion exchange model is applied to derive the mechanism. • Binding constants are in the range of 10{sup 2}–10{sup 4} M{sup −1}.

  13. RutheniumII Complexes bearing Fused Polycyclic Ligands: From Fundamental Aspects to Potential Applications

    Directory of Open Access Journals (Sweden)

    Ludovic Troian-Gautier

    2014-04-01

    Full Text Available In this review, we first discuss the photophysics reported in the literature for mononuclear ruthenium complexes bearing ligands with extended aromaticity such as dipyrido[3,2-a:2',3'-c]phenazine (DPPZ, tetrapyrido[3,2-a:2',3'-c:3'',2''-h:2''',3'''-j]-phenazine (TPPHZ,  tetrapyrido[3,2-a:2',3'-c:3'',2''-h:2''',3'''-j]acridine (TPAC, 1,10-phenanthrolino[5,6-b]1,4,5,8,9,12-hexaazatriphenylene (PHEHAT 9,11,20,22-tetraaza- tetrapyrido[3,2-a:2',3'-c:3'',2''-l:2''',3'''-n]pentacene (TATPP, etc. Photophysical properties of binuclear and polynuclear complexes based on these extended ligands are then reported. We finally develop the use of binuclear complexes with extended π-systems for applications such as photocatalysis.

  14. Photo-induced DNA cleavage and cytotoxicity of a ruthenium(II) arene anticancer complex

    Czech Academy of Sciences Publication Activity Database

    Brabec, Viktor; Prachařová, J.; Štěpánková, Jana; Sadler, P. J.; Kašpárková, Jana

    2016-01-01

    Roč. 160, JUL2016 (2016), s. 149-155 ISSN 0162-0134 R&D Projects: GA ČR(CZ) GA14-21053S; GA MŠk(CZ) LD14019 Institutional support: RVO:68081707 Keywords : Ruthenium anticancer complex * DNA cleavage * Phototoxicity Subject RIV: BO - Biophysics Impact factor: 3.348, year: 2016

  15. Cobalt(III), nickel(II) and ruthenium(II) complexes of 1,10 ...

    Indian Academy of Sciences (India)

    Co(II) and Ru(II) complexes investigated in this study effect photocleavage of the supercoiled ... DNA is related to their utility in the design and development of synthetic restriction ..... ∗Quasi-reversible/irreversible (electrochemical behaviour of ...

  16. Arene ruthenium(II) azido complexes incorporating N intersection O chelate ligands: Synthesis, spectral studies and 1,3-dipolar-cycloaddition to a coordinated azide in ruthenium(II) compounds

    Digital Repository Service at National Institute of Oceanography (India)

    Singh, K.S.; Kaminsky, W.

    showed a slightly different spectra pattern for p- cymene ligand as compared to the rest of the complexes. For instant, the complex 1 exhibits two doublets for diastereotopic methyl protons of the isopropyl group at around δ 1.12-0.99 (Fig. 1). Likewise... formed are exclusively N(2) bound isomer which is supported by their NMR spectral data. For instant, the proton NMR spectrum of 8 displayed a, singlet at δ 3.75 assignable to the protons of a methoxy carbonyl group while for complex 9 a quartet...

  17. Some mixed ligand hydridocarbonyl and hydridophosphine complexes of ruthenium(II) and iridium(III)

    International Nuclear Information System (INIS)

    Pandey, R.N.; Kumar, Sunil; Kumar, Arun; Kumar, S.K.

    1993-01-01

    Mixed-ligand hydridocarbonyl and hydridophosphine complexes of Ru II and Ir III have been isolated from the displacement reaction of [RuH(CO)(Pφ 3 ) 3 Cl] with ligand isonicotinic acid hydrazide (INAH) in benzene medium. Most probable structures are assigned on the basis of elemental analysis, electronic, infrared and far-infrared spectral studies. In all cases bonding of INAH occurs through amino nitrogen of hydrazine residue. (author). 15 refs., 1 tab

  18. Crystal structure and physical properties of a ruthenium(II) bipyridine dimethylsulfoxide complex

    International Nuclear Information System (INIS)

    Wang, Y.; Eichhorn, D.M.; Goswami, N.; Zhao, Q.; Rillema, D.P.

    1999-01-01

    The complex [Ru(bpy) 2 (DMSO)C1]PF 6 , where bpy is 2,2prime-bipyridine and DMSO is dimethyl-sulfoxide, crystallizes in the triclinic space group Pbar 1 (number s ign2) with a = 8.873 (2), b = 12.805 (4), c = 12.864 (4) angstrom, α = 97.76(3), β = 106.45(2), γ = 107.88(2); Z = 2, and d calc = 1.75 mg/m 3 . The coordination geometry is that of a distorted octahedron with a cis-RuN 4 SCl arrangement of coordinating atoms. The four Ru-N distances to the bpy ligands are 2.082(5), 2.092(4), 2.044(4), and 2.078(5) angstrom. The Ru-Cl distance is 2.421(2) angstrom and the Ru-S distance to DMSO is 2.260(1) angstrom. The Ru-N bond distance trans to Cl is the shortest; the Ru-N bond distance trans to S is the longest. The complex is oxidized and reduced reversibly at 1.13 and minus1.37 V vs. SSCE, respectively. It displays electronic absorptions at 515, 480 (1.5 x 10 4 ), 342 (1.5 X 10 4 ), 292 (1.2 X 10 5 ), and 240 nm (6.2 x 10 4 ) and has a broad emission band centered at 607 nm at 77 K in a 4:1 ethanol/methanol glass. The emission lifetime at room temperature is less than the pulse width of the laser, τ < 20 ns

  19. Ruthenium(II) bipyridine complexes bearing quinoline-azoimine (NN'N″) tridentate ligands: synthesis, spectral characterization, electrochemical properties and single-crystal X-ray structure analysis.

    Science.gov (United States)

    Al-Noaimi, Mousa; Abdel-Rahman, Obadah S; Fasfous, Ismail I; El-khateeb, Mohammad; Awwadi, Firas F; Warad, Ismail

    2014-05-05

    Four octahedral ruthenium(II) azoimine-quinoline complexes having the general molecular formula [Ru(II)(L-Y)(bpy)Cl](PF6) {L-Y=YC6H4N=NC(COCH3)=NC9H6N, Y=H (1), CH3 (2), Br (3), NO2 (4) and bpy=2,2'-bipyrdine} were synthesized. The azoimine-quinoline based ligands behave as NN'N″ tridentate donors and coordinated to ruthenium via azo-N', imine-N' and quinolone-N″ nitrogen atoms. The composition of the complexes has been established by elemental analysis, spectral methods (FT-IR, electronic, (1)H NMR, UV/Vis and electrochemical (cyclic voltammetry) techniques. The crystal structure of complex 1 is reported. The Ru(II) oxidation state is greatly stabilized by the novel tridentate ligands, showing Ru(III/II) couples ranging from 0.93-1.27 V vs. Cp2Fe/Cp2Fe(+). The absorption spectrum of 1 in dichloromethane was modeled by time-dependent density functional theory (TD-DFT). Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Robust binding between carbon nitride nanosheets and a binuclear ruthenium(II) complex enabling durable, selective CO{sub 2} reduction under visible light in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Kuriki, Ryo; Ishitani, Osamu; Maeda, Kazuhiko [Department of Chemistry, School of Science, Tokyo Institute of Technology (Japan); Yamamoto, Muneaki; Yoshida, Tomoko [Advanced Research Institute for Natural Science and Technology, Osaka City University (Japan); Higuchi, Kimitaka; Yamamoto, Yuta; Akatsuka, Masato; Yagi, Shinya [Institute of Materials and Systems for Sustainability, Nagoya University (Japan); Lu, Daling [Suzukakedai Materials Analysis Division, Technical Department, Tokyo Institute of Technology, Yokohama (Japan)

    2017-04-18

    Carbon nitride nanosheets (NS-C{sub 3}N{sub 4}) were found to undergo robust binding with a binuclear ruthenium(II) complex (RuRu') even in basic aqueous solution. A hybrid material consisting of NS-C{sub 3}N{sub 4} (further modified with nanoparticulate Ag) and RuRu' promoted the photocatalytic reduction of CO{sub 2} to formate in aqueous media, in conjunction with high selectivity (approximately 98 %) and a good turnover number (>2000 with respect to the loaded Ru complex). These represent the highest values yet reported for a powder-based photocatalytic system during CO{sub 2} reduction under visible light in an aqueous environment. We also assessed the desorption of RuRu' from the Ag/C{sub 3}N{sub 4} surface, a factor that can contribute to a loss of activity. It was determined that desorption is not induced by salt additives, pH changes, or photoirradiation, which partly explains the high photocatalytic performance of this material. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Influence of different ruthenium(II) bipyridyl complex on the photocatalytic H{sub 2} evolution over TiO{sub 2} nanoparticles with mesostructures

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Tianyou [College of Chemistry and Molecular Science, Wuhan University, Wuhan 430072 (China); Hubei Key Laboratory for Catalysis and Material Science, College of Chemistry and Material Science, South-Central University for Nationalities, Wuhan 430074 (China); Ke, Dingning; Cai, Ping; Dai, Ke; Ma, Liang; Zan, Ling [College of Chemistry and Molecular Science, Wuhan University, Wuhan 430072 (China)

    2008-05-15

    H{sub 2} production over dye-sensitized Pt/TiO{sub 2} nanoparticles with mesostructures (m-TiO{sub 2}) under visible light ({lambda} > 420 nm) was investigated by using methanol as electron donors. Experimental results indicate that three types of ruthenium(II) bipyridyl complex dyes (one binuclear Ru, two mononuclear Ru), which can be attached to Pt/m-TiO{sub 2} with different linkage modes, show different photosensitization effects due to their different coordination circumstances and physicochemical properties. The dye tightly linked with m-TiO{sub 2} has better durability but the lowest H{sub 2} evolution efficiency, whereas the loosely attached dyes possess higher H{sub 2} evolution efficiency and preferable durability. It seems that the dynamic equilibrium between the linkage of the ground state dye with TiO{sub 2} and the divorce of the oxidization state dye from the surfaces plays a crucial role in the photochemical behavior during the photocatalyst sensitization process. It is helpful to improve the H{sub 2} evolution efficiency by enhancing the electron injection and hindering the backward transfer. The binuclear Ru(II) dye shows a better photosensitization in comparison with mononuclear Ru(II) dyes due to its large molecular area, conjugation system, and ''antenna effect'', which, in turn, improve the visible light harvesting and electron transfer between the dye molecules and TiO{sub 2}. (author)

  2. A ruthenium(II) complex as turn-on Cu(II) luminescent sensor based on oxidative cyclization mechanism and its application in vivo

    Science.gov (United States)

    Zhang, Yunfei; Liu, Zonglun; Yang, Kui; Zhang, Yi; Xu, Yongqian; Li, Hongjuan; Wang, Chaoxia; Lu, Aiping; Sun, Shiguo

    2015-02-01

    Copper ions play a vital role in a variety of fundamental physiological processes not only in human beings and plants, but also for extensive insects and microorganisms. In this paper, a novel water-soluble ruthenium(II) complex as a turn-on copper(II) ions luminescent sensor based on o-(phenylazo)aniline was designed and synthesized. The azo group would undergo a specific oxidative cyclization reaction with copper(II) ions and turn into high luminescent benzotriazole, triggering significant luminescent increasements which were linear to the concentrations of copper(II) ions. The sensor distinguished by its high sensitivity (over 80-fold luminescent switch-on response), good selectivity (the changes of the emission intensity in the presence of other metal ions or amino acids were negligible) and low detection limit (4.42 nM) in water. Moreover, the copper(II) luminescent sensor exhibited good photostability under light irradiation. Furthermore, the applicability of the proposed sensor in biological samples assay was also studied and imaged copper(II) ions in living pea aphids successfully.

  3. Post-synthetic modification of mesoporous zinc-adeninate framework with tris(2,2′-biprydine) ruthenium(II) complex and its electrochemiluminescence

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ji Eun; Shin, Ik Soo [Dept. of Chemistry, Soongsil University, Seoul (Korea, Republic of); Oh, Hye Jae; An, Ji Hyun [Dept. of Chemistry Education, Seoul National University, Seoul (Korea, Republic of)

    2017-04-15

    Herein we report a redox-active metal-organic framework (MOF) via post-synthetic cation exchange with tris(2,2′-biprydine) ruthenium(II) complex (Ru(bpy){sub 3}{sup 2+}). A porous anionic zinc-adeninate framework (bMOF-100) is spacious enough to easily entrap 2.43 of Ru(bpy){sub 3}{sup 2+} cations within the mesopore. The encapsulation supported the framework structure preventing any distortion from a rapid solvent evaporation under SEM observation. Ru(bpy){sub 3}{sup 2+}@bMOF-100 was then immobilized on the surface of glassy carbon electrode, and its electrocatalytic and electrochemiluminescent (ECL) properties were investigated in aqueous and organic solution. Especially, Ru(bpy){sub 3}{sup 2+}@bMOF-100 showed the excellent electrochemical properties of Ru(bpy){sub 3}{sup 2+}, but gradual decomposition of the MOF structure was observed under electrochemical measurements because of the sluggish oxidation of adeninate ligand.

  4. In vitro evaluation of the cyto-genotoxic potential of Ruthenium(II) SCAR complexes: a promising class of antituberculosis agents.

    Science.gov (United States)

    De Grandis, Rone Aparecido; Resende, Flávia Aparecida; da Silva, Monize Martins; Pavan, Fernando Rogério; Batista, Alzir Azevedo; Varanda, Eliana Aparecida

    2016-03-01

    Tuberculosis is a top infectious disease killer worldwide, caused by the bacteria Mycobacterium tuberculosis. Increasing incidences of multiple drug-resistance (MDR) strains are emerging as one of the major public health threats. However, the drugs in use are still incapable of controlling the appalling upsurge of MDR. In recent years a marked number of research groups have devoted their attention toward the development of specific and cost-effective antimicrobial agents against targeted MDR-Tuberculosis. In previous studies, ruthenium(II) complexes (SCAR) have shown a promising activity against MDR-Tuberculosis although few studies have indeed considered ruthenium toxicity. Therefore, within the preclinical requirements, we have sought to determine the cyto-genotoxicity of three SCAR complexes in this present study. The treatment with the SCARs induced a concentration-dependent decrease in cell viability in CHO-K1 and HepG2 cells. Based on the clonogenic survival, SCAR 5 was found to be more cytotoxic while SCAR 6 exhibited selectivity action on tumor cells. Although SCAR 4 and 5 did not indicate any mutagenic activity as evidenced by the Ames and Cytokinesis block micronucleus cytome assays, the complex SCAR 6 was found to engender a frameshift mutation detected by Salmonella typhimurium in the presence of S9. Similarly, we observed a chromosomal damage in HepG2 cells with significant increases of micronuclei and nucleoplasmic bridges. These data indicate that SCAR 4 and 5 complexes did not show genotoxicity in our models while SCAR 6 was considered mutagenic. This study presented a comprehensive genotoxic evaluation of SCAR complexes were shown to be genotoxic in vitro. All in all, further studies are required to fully elucidate how the properties can affect human health. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Reductive coupling of carbon monoxide in a rhenium carbonyl complex with pendant Lewis acids.

    Science.gov (United States)

    Miller, Alexander J M; Labinger, Jay A; Bercaw, John E

    2008-09-10

    Phosphinoborane ligands impart unique reactivity to a rhenium carbonyl cation relative to simple phosphine complexes. Addition of either triethylborohydride or a platinum hydride (that can be formed from H2) forms a rhenium boroxycarbene. This carbene, which crystallizes as a dimer, disproportionates over a period of days to afford the starting cation and a structurally unprecedented boroxy(boroxymethyl)carbene, in which a new C-C bond has been formed between two reduced CO ligands. This product of C-C bond formation can be independently synthesized by addition of 2 equiv of hydride to the rhenium carbonyl cation.

  6. Gas-phase chemistry of Mo, Ru, W, and Os metal carbonyl complexes

    International Nuclear Information System (INIS)

    Wang, Y.; Qin, Z.; Fan, F.L.

    2014-01-01

    Metal carbonyl complexes were used for studying the gas-phase chemical behavior of Mo, Ru, W and Os isotopes with an on-line low temperature isothermal gas chromatography apparatus. Short-lived Mo and Ru isotopes were produced by a 252 Cf spontaneous fission source. Short-lived nuclides of W and Os were produced using the heavy ion reactions 19 F + 159 Tb and 165 Ho, respectively. Short-lived products were thermalized in a recoil chamber filled with a gas mixture of helium and carbon monoxide. The carbonyls formed were then transported through capillaries to an isothermal chromatography column for study of the adsorption behavior as a function of temperature. On-line isothermal chromatography (IC) experiments on Teflon (PTFE) and quartz surfaces showed that short-lived isotopes of the listed elements can form carbonyl complexes which are very volatile and interact most likely in physical sorption processes. Deduced adsorption enthalpies of Mo and Ru carbonyls were -38 ± 2 kJ/mol and -36 ± 2 kJ/mol, respectively. These values are in good agreement with literature data, partly obtained with different chromatographic techniques. A validation of the applied Monte Carlo model to deduce adsorption enthalpies with Mo isotopes of different half-lives proved the validity of the underlying adsorption model. The investigations using a gas-jet system coupled to a heavy ion accelerator without any preseparator clearly showed the limitations of the approach. The He and CO gas mixture, which was directly added into the chamber, will result in decomposition of CO gas and produce some aerosol particles. After the experiment of 173 W and 179 Os in the heavy ion experiments, the Teflon column was covered by a yellowish deposit; the adsorption enthalpy of W and Os carbonyls could therefore not be properly deduced using Monte Carlo simulations. (orig.)

  7. Reductive Coupling of Carbon Monoxide in a Rhenium Carbonyl Complex with Pendant Lewis Acids

    OpenAIRE

    Miller, Alexander J. M.; Labinger, Jay A.; Bercaw, John E.

    2008-01-01

    Phosphinoborane ligands impart unique reactivity to a rhenium carbonyl cation relative to simple phosphine complexes. Addition of either triethylborohydride or a platinum hydride (that can be formed from H2) forms a rhenium boroxycarbene. This carbene, which crystallizes as a dimer, disproportionates over a period of days to afford the starting cation and a structurally unprecedented boroxy(boroxymethyl)carbene, in which a new C−C bond has been formed between two reduced CO ligands. This prod...

  8. Ruthenium(II) arene complexes with chelating chloroquine analogue ligands: Synthesis, characterization and in vitro antimalarial activity†

    Science.gov (United States)

    Glans, Lotta; Ehnbom, Andreas; de Kock, Carmen; Martínez, Alberto; Estrada, Jesús; Smith, Peter J.; Haukka, Matti; Sánchez-Delgado, Roberto A.; Nordlander, Ebbe

    2012-01-01

    Three new ruthenium complexes with bidentate chloroquine analogue ligands, [Ru(η6-cym)(L1)Cl]Cl (1, cym = p-cymene, L1 = N-(2-((pyridin-2-yl)methylamino)ethyl)-7-chloroquinolin-4-amine), [Ru(η6-cym)(L2)Cl]Cl (2, L2 = N-(2-((1-methyl-1H-imidazol-2-yl)methylamino)ethyl)-7-chloroquinolin-4-amine) and [Ru(η6-cym)(L3)Cl] (3, L3 = N-(2-((2-hydroxyphenyl)methylimino)ethyl)-7-chloroquinolin-4-amine) have been synthesized and characterized. In addition, the X-ray crystal structure of 2 is reported. The antimalarial activity of complexes 1–3 and ligands L1, L2 and L3, as well as the compound N-(2-(bis((pyridin-2-yl)methyl)amino)ethyl)-7-chloroquinolin-4-amine (L4), against chloroquine sensitive and chloroquine resistant Plasmodium falciparum malaria strains was evaluated. While 1 and 2 are less active than the corresponding ligands, 3 exhibits high antimalarial activity. The chloroquine analogue L2 also shows good activity against both the choloroquine sensitive and the chloroquine resistant strains. Heme aggregation inhibition activity (HAIA) at an aqueous buffer/n-octanol interface (HAIR50) and lipophilicity (D, as measured by water/n-octanol distribution coefficients) have been measured for all ligands and metal complexes. A direct correlation between the D and HAIR50 properties cannot be made because of the relative structural diversity of the complexes, but it may be noted that these properties are enhanced upon complexation of the inactive ligand L3 to ruthenium, to give a metal complex (3) with promising antimalarial activity. PMID:22249579

  9. Ruthenium(II) chloro-bis(bipyridyl) complexes with substituted pyridine ligands: interpretation of their electronic absorption spectra

    International Nuclear Information System (INIS)

    Sizova, O.V.; Ershov, A.Yu.; Ivanova, N.V.; Shashko, A.D.; Kutejkina-Teplyakova, A.V.

    2003-01-01

    A number of complexes cis-[Ru(Bipy) 2 (L)(Cl)](BF 4 ), where Bipy-2,2'-bipyridine, L-pyridine, 4-aminopyridine, 4-picoline, nicotinamide, isonicotinamide, 3- and 4-cyanopyridine, 4,4'-bipyridine, trans-1,2-bis(4-pyridyl)ethylene, 4,4'-azopyridine, pyrazine, imidazole and NH 3 , were prepared. Using the CINDO-CI semiempirical method the energies and intensities of transition in electronic absorption spectra (EAS) of the complexes were calculated. It is shown that major differences in EAS of the compounds stem from position of transitions with charge transfer d π (Ru)→π*(L) [ru

  10. Hydrogenation of imines catalysed by ruthenium(II) complexes based on lutidine-derived CNC pincer ligands.

    Science.gov (United States)

    Hernández-Juárez, Martín; Vaquero, Mónica; Álvarez, Eleuterio; Salazar, Verónica; Suárez, Andrés

    2013-01-14

    The preparation of new Ru(II) complexes incorporating fac-coordinated lutidine-derived CNC ligands is reported. These derivatives are selectively deprotonated by (t)BuOK at one of the methylene arms of the pincer, leading to catalytically active species in the hydrogenation of imines.

  11. Oxidation of Bromide to Bromine by Ruthenium(II) Bipyridine-Type Complexes Using the Flash-Quench Technique.

    Science.gov (United States)

    Tsai, Kelvin Yun-Da; Chang, I-Jy

    2017-07-17

    Six ruthenium complexes, [Ru(bpy) 3 ] 2+ (1), [Ru(bpy) 2 (deeb)] 2+ (2), [Ru(deeb) 2 (dmbpy)] 2+ (3), [Ru(deeb) 2 (bpy)] 2+ (4), [Ru(deeb) 3 ] 2+ (5), and [Ru(deeb) 2 (bpz)] 2+ (6) (bpy: 2,2'-bipyridine; deeb: 4,4'-diethylester-2,2'-bipyridine; dmbpy: 4,4'-dimethyl-2,2'-bipyridine, bpz: 2,2'-bipyrazine), have been employed to sensitize photochemical oxidation of bromide to bromine. The oxidation potential for complexes 1-6 are 1.26, 1.36, 1.42, 1.46, 1.56, and 1.66 V vs SCE, respectively. The bimolecular rate constants for the quenching of complexes 1-6 by ArN 2 + (bromobenzenediazonium) are determined as 1.1 × 10 9 , 1.6 × 10 8 , 1.4 × 10 8 , 1.2 × 10 8 , 6.4 × 10 7 , and 8.9 × 10 6 M -1 s -1 , respectively. Transient kinetics indicated that Br - reacted with photogenerated Ru(III) species at different rates. Bimolecular rate constants for the oxidation of Br - by the Ru(III) species derived from complexes 1-5 are observed as 1.2 × 10 8 , 1.3 × 10 9 , 4.0 × 10 9 , 4.8 × 10 9 , and 1.1 × 10 10 , M -1 s -1 , respectively. The last reaction kinetics observed in the three-component system consisting of a Ru sensitizer, quencher, and bromide is shown to be independent of the Ru sensitizer. The final product was identified as bromine by its reaction with hexene. The last reaction kinetics is assigned to the disproportionation reaction of Br 2 -• ions, for which the rate constant is determined as 5 × 10 9 M -1 s -1 . Though complex 6 has the highest oxidation potential in the Ru(II)/Ru(III) couple, its excited state fails to react with ArN 2 + sufficiently for subsequent reactions. The Ru(III) species derived from complex 1 reacts with Br - at the slowest rate. Complexes 2-5 are excellent photosensitizers to drive photooxidation of bromide to bromine.

  12. Ruthenium(II) bipyridine complexes bearing new keto-enol azoimine ligands: synthesis, structure, electrochemistry and DFT calculations.

    Science.gov (United States)

    Al-Noaimi, Mousa; Awwadi, Firas F; Mansi, Ahmad; Abdel-Rahman, Obadah S; Hammoudeh, Ayman; Warad, Ismail

    2015-01-25

    The novel azoimine ligand, Ph-NH-N=C(COCH3)-NHPh(C≡CH) (H2L), was synthesized and its molecular structure was determined by X-ray crystallography. Catalytic hydration of the terminal acetylene of H2L in the presence of RuCl3·3H2O in ethanol at reflux temperature yielded a ketone (L1=Ph-N=N-C(COCH3)=N-Ph(COCH3) and an enol (L2=Ph-N=N-C(COCH3)=N-PhC(OH)=CH2) by Markovnikov addition of water. Two mixed-ligand ruthenium complexes having general formula, trans-[Ru(bpy)(Y)Cl2] (1-2) (where Y=L1 (1) and Y=L2 (2), bpy is 2.2'-bipyrdine) were achieved by the stepwise addition of equimolar amounts of (H2L) and bpy ligands to RuCl3·3H2O in absolute ethanol. Theses complexes were characterized by elemental analyses and spectroscopic (IR, UV-Vis, and NMR (1D (1)H NMR, (13)C NMR, (DEPT-135), (DEPT-90), 2D (1)H-(1)H and (13)C-(1)H correlation (HMQC) spectroscopy)). The two complexes exhibit a quasi-reversible one electron Ru(II)/Ru(III) oxidation couple at 604 mV vs. ferrocene/ferrocenium (Cp2Fe(0/+)) couple along with one electron ligand reduction at -1010 mV. The crystal structure of complex 1 showed that the bidentate ligand L1 coordinates to Ru(II) by the azo- and imine-nitrogen donor atoms. The complex adopts a distorted trans octahedral coordination geometry of chloride ligands. The electronic spectra of 1 and 1+ in dichloromethane have been modeled by time-dependent density functional theory (TD-DFT). Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Asymmetric Ruthenium(II and Osmium(II Complexes with New Bidentate Polyquinoline Ligands. Synthesis and NMR Characterization

    Directory of Open Access Journals (Sweden)

    Antonino Mamo

    2010-03-01

    Full Text Available A series of Ru(II and Os(II tris-chelate complexes with new bidentate 2-pyridylquinoline ligands have been synthesized and fully characterized by EA,1H-NMR and FAB-MS techniques. The new ligands are: L1 = 4-p-methoxyphenyl-6-bromo-2-(2′- pyridylquinoline (mphbr-pq and L2 = 4-p-hydroxyphenyl-6-bromo-2-(2′-pyridyl-quinoline (hphbr-pq. The complexes studied are: [Ru(bpy2L1](PF62 (C1, [Ru(bpy2L2](PF62 (C2, [Os(bpy2L1](PF62 (C3, [Os(bpy2L2](PF62 (C4 (bpy = 2,2′-bipyridine, [Ru(dmbpy2L1](PF62 (C5, [Ru(dmbpy2L2](PF62 (C6, [Os(dmbpy2L1](PF62 (C7, and [Os(dmbpy2L2](PF62 (C8 (dmbpy = 4,4′-dimethyl-2,2′-bipyridine. Moreover, new functionalized complexes C9-C12 were obtained by the basecatalyzed direct alkylation of C2, C4, C6, and C8 with 6-bromo-1-hexene. The complete assignment of the 1H-NMR spectra for the two new ligands (L1 and L2, and their Ru(II or Os(II complexes has been accomplished using a combination of one- and two-dimensional NMR techniques. The JH,H values have been determined for the majority of the resonances.

  14. Aquation Is a Crucial Activation Step for Anticancer Action of Ruthenium(II) Polypyridyl Complexes to Trigger Cancer Cell Apoptosis.

    Science.gov (United States)

    Li, Meng; Lai, Lanhai; Zhao, Zhennan; Chen, Tianfeng

    2016-01-01

    Aquation has been proposed as crucial chemical action step for ruthenium (Ru) complexes, but its effects on the action mechanisms remain elusive. Herein, we have demonstrated the aquation process of a potent Ru polypyridyl complex (RuBmp=[Ru(II) (bmbp)(phen)Cl]ClO4 , bmbp=2,6-bis(6-methylbenzimidazol-2-yl) pyridine, phen=phenanthroline) with a chloride ligand, and revealed that aquation of RuBmp effectively enhanced its hydrophilicity and cellular uptake, thus significantly increasing its anticancer efficacy. The aquation products (H-RuBmp=[Ru(II) (bmbp)(phen)Cl]ClO4 , [Ru(II) (bmbp)(phen)(H2 O)]ClO4 , bmbp) exhibited a much higher apoptosis-inducing ability than the intact complex, with involvement of caspase activation, mitochondria dysfunction, and interaction with cell membrane death receptors. H-RuBmp demonstrated a higher interaction potency with the cell membrane and induced higher levels of ROS overproduction in cancer cells to regulate the AKT, MAPK, and p53 signaling pathways. Taken together, this study could provide useful information for fine-tuning the rational design of next-generation metal medicines. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Electrochemical synthesis of transition element complexes with carboxyl- and carbonyl-containing ligands

    International Nuclear Information System (INIS)

    Frolov, V.Yu.; Bolotin, S.N.; Panyushkin, V.T.

    2005-01-01

    Complexes of d- and f-elements (E = Cu, Ni, Zn, Nd, Tb, Pr, Gd, Er) with carboxyl- and carbonyl-containing ligands were synthesized by the electrochemical method. The products were characterized by elemental analysis, thermal gravimetric analysis and IR spectra. The influence exerted by a number of factors on the process course was studied. The dependence of the electro synthesis parameters on the composition of the forming compounds was established. A new method for anodic synthesis of these compounds was developed [ru

  16. Incorporation of amphiphilic ruthenium(II) ammine complexes into Langmuir-Blodgett thin films with switchable quadratic nonlinear optical behavior.

    Science.gov (United States)

    Boubekeur-Lecaque, Leïla; Coe, Benjamin J; Harris, James A; Helliwell, Madeleine; Asselberghs, Inge; Clays, Koen; Foerier, Stijn; Verbiest, Thierry

    2011-12-19

    Nine nonlinear optical (NLO) chromophores with pyridinium electron acceptors have been synthesized by complexing new proligands with {Ru(II)(NH(3))(5)}(2+) electron-donor centers. The presence of long alkyl/fluoroalkyl chain substituents imparts amphiphilic properties, and these cationic complexes have been characterized as their PF(6)(-) salts by using various techniques including electronic absorption spectroscopy and cyclic voltammetry. Each complex shows three reversible/quasireversible redox processes; a Ru(III/II) oxidation and two ligand-based reductions. The energies of the intense visible d → π* metal-to-ligand charge-transfer (MLCT) absorptions correlate to some extent with the ligand reduction potentials. (1)H NMR spectroscopy also provides insights into the relative electron-withdrawing strengths of the new ligands. Single crystal X-ray structures have been determined for two of the proligand salts and one complex salt, [Ru(II)(NH(3))(5)(4-C(16)H(33)PhQ(+))]Cl(3)·3.25H(2)O (PhQ(+) = N-phenyl-4,4'-bipyridinium), showing centrosymmetric packing structures in each case. The PF(6)(-) analogue of the latter complex has been used to deposit reproducibly high-quality, multilayered Langmuir-Blodgett (LB) thin films. These films show a strong second harmonic generation (SHG) response from a 1064 nm laser; their MLCT absorbance increases linearly with the number of layers (N) and I(2ω)/I(ω)(2) (I(2ω) = intensity at 532 nm; I(ω) = intensity at 1064 nm) scales quadratically with N, consistent with homogeneous deposition. LB films on indium tin oxide (ITO)-coated glass show electrochemically induced switching of the SHG response, with a decrease in activity of about 50% on Ru(II) → Ru(III) oxidation. This effect is reversible, but reproducible over only a few cycles before the signal from the Ru(II) species diminishes. This work extrapolates our original solution studies (Coe, B. J. et al. Angew. Chem., Int. Ed.1999, 38, 366) to the first demonstration of

  17. A low frequency infrared study of ruthenium(II) complexes with 1,8-naphthyridines and 2,2'-bipyridine

    International Nuclear Information System (INIS)

    Staniewicz, R.J.; Hendricker, D.G.; Griffiths, P.R.

    1977-01-01

    A report is presented on the synthesis and characterization of [Ru(napy) 4 ](PF 6 ) 2 , [Ru(2-mnapy) 4 ] (PF 6 ) 2 , [Ru(2,7-dmnapy) 3 ] (PF 6 ) 2 and [Ru(bipy) 3 ] (PF 6 ) 2 ; where (napy) = 1,8-naphthyridine; (2,7-dmnapy) = 2,7-dimethyl-1, 8-naphthyridine; (2-mnapy) = 2-methyl-1, 8-naphthyridine, and (bipy) = bipyridine. The complexes were prepared as previously reported (Staniewicz et al., (J.Am.Chem.Soc., in the press)). Low frequency infrared spectra were measured using a Digilab FTS-14 Fourier transform spectrophotometer. The results are discussed. Molecular structures are proposed. (U.K.)

  18. Influence of the π-coordinated arene on the anticancer activity of ruthenium(II carbohydrate organometallic complexes

    Directory of Open Access Journals (Sweden)

    Muhammad eHanif

    2013-10-01

    Full Text Available The synthesis and in vitro cytotoxicity of a series of RuII(arene complexes with carbohydrate-derived phosphite ligands and various arene co-ligands is described. The arene ligand has a strong influence on the in vitro anticancer activity of this series of compounds, which correlates fairly well with cellular accumulation. The most lipophilic compound bearing a biphenyl moiety and a cyclohexylidene-protected carbohydrate is the most cytotoxic with unprecedented IC50 values for the compound class in three human cancer cell lines. This compound shows reactivity to the DNA model nucleobase 9-ethylguanine, but does not alter the secondary structure of plasmid DNA indicating that other biological targets are responsible for its cytotoxic effect.

  19. Highly efficient and stable cyclometalated ruthenium(II) complexes as sensitizers for dye-sensitized solar cells

    International Nuclear Information System (INIS)

    Huang, Jian-Feng; Liu, Jun-Min; Su, Pei-Yang; Chen, Yi-Fan; Shen, Yong; Xiao, Li-Min; Kuang, Dai-Bin; Su, Cheng-Yong

    2015-01-01

    Highlights: • Four novel thiocyanate-free cyclometalated ruthenium sensitizer were conveniently synthesized. • The D-CF 3 -sensitized DSSCs show higher efficiency compared to N719 based cells. • The DSSCs based on D-CF 3 and D-bisCF 3 sensitizers exhibit excellent long-term stability. • The diverse cyclometalated Ru complexes can be developed as high-performance sensitizers for use in DSSC. - Abstract: Four novel thiocyanate-free cyclometallted Ru(II) complexes, D-bisCF 3 , D-CF 3 , D-OMe, and D-DPA, with two 4,4′-dicarboxylic acid-2,2′-bipyridine together with a functionalized phenylpyridine ancillary ligand, have been designed and synthesized. The effect of different substituents (R = bisCF 3 , CF 3 , OMe, and DPA) on the ancillary C^N ligand on the photophysical properties and photovoltaic performance is investigated. Under standard global AM 1.5 solar conditions, the device based on D-CF 3 sensitizer gives a higher conversion efficiency of 8.74% than those based on D-bisCF 3 , D-OMe, and D-DPA, which can be ascribed to its broad range of visible light absorption, appropriate localization of the frontier orbitals, weak hydrogen bonds between -CF 3 and -OH groups at the TiO 2 surface, moderate dye loading on TiO 2 , and high charge collection efficiency. Moreover, the D-bisCF 3 and D-CF 3 based DSSCs exhibit good stability under 100 mW cm −2 light soaking at 60 °C for 400 h

  20. Diverse roles of hydrogen in rhenium carbonyl chemistry: hydrides, dihydrogen complexes, and a formyl derivative.

    Science.gov (United States)

    Li, Nan; Xie, Yaoming; King, R Bruce; Schaefer, Henry F

    2010-11-04

    Rhenium carbonyl hydride chemistry dates back to the 1959 synthesis of HRe(CO)₅ by Hieber and Braun. The binuclear H₂Re₂(CO)₈ was subsequently synthesized as a stable compound with a central Re₂(μ-H)₂ unit analogous to the B₂(μ-H)₂ unit in diborane. The complete series of HRe(CO)(n) (n = 5, 4, 3) and H₂Re₂(CO)(n) (n = 9, 8, 7, 6) derivatives have now been investigated by density functional theory. In contrast to the corresponding manganese derivatives, all of the triplet rhenium structures are found to lie at relatively high energies compared with the corresponding singlet structures consistent with the higher ligand field splitting of rhenium relative to manganese. The lowest energy HRe(CO)₅ structure is the expected octahedral structure. Low-energy structures for HRe(CO)(n) (n = 4, 3) are singlet structures derived from the octahedral HRe(CO)₅ structure by removal of one or two carbonyl groups. For H₂Re₂(CO)₉ a structure HRe₂(CO)₉(μ-H), with one terminal and one bridging hydrogen atom, lies within 3 kcal/mol of the structure Re₂(CO)₉(η²-H₂), similar to that of Re₂(CO)₁₀. For H₂Re₂(CO)(n) (n = 8, 7, 6) the only low-energy structures are doubly bridged singlet Re₂(μ-H)₂(CO)(n) structures. Higher energy dihydrogen complex structures are also found.

  1. Identification of the non-pertechnetate species in Hanford waste tanks, Tc(I) carbonyl complexes

    Energy Technology Data Exchange (ETDEWEB)

    Lukens, Wayne W.; Shuh, David K.; Schroeder, Norman C.; Ashley, Kenneth R.

    2003-10-16

    Immobilization of the high-level nuclear waste stored at the Hanford Reservation has been complicated by the presence of soluble, lower-valent technetium species. Previous work by Schroeder and Blanchard has shown that these species cannot be removed by ion-exchange and are difficult to oxidize. The Tc-K edge XANES spectra of the species in Tanks SY-101 and SY-103 were reported by Blanchard, but they could not be assigned to any known technetium complex. We report that the XANES spectra are most likely those of Tc(I) carbonyl species, especially fac-Tc(CO){sub 3}(gluconate){sup 2-}. This is further supported by EXAFS and {sup 99}Tc-NMR studies in nonradioactive simulants of these tank wastes.

  2. Cellular responses of BRCA1-defective and triple-negative breast cancer cells and in vitro BRCA1 interactions induced by metallo-intercalator ruthenium(II) complexes containing chloro-substituted phenylazopyridine

    International Nuclear Information System (INIS)

    Nhukeaw, Tidarat; Temboot, Pornvichai; Hansongnern, Kanidtha; Ratanaphan, Adisorn

    2014-01-01

    Triple-negative breast cancer (TNBC) is defined by the absence of expression of estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2. Breast cancers with a BRCA1 mutation are also frequently triple-negative. Currently, there is a lack of effective therapies and known specific molecular targets for this aggressive breast cancer subtype. To address this concern, we have explored the cellular responses of BRCA1-defective and triple-negative breast cancer cells, and in vitro BRCA1 interactions induced by the ruthenium(II) complexes containing the bidentate ligand, 5-chloro-2-(phenylazo)pyridine. Triple-negative MDA-MB-231, BRCA1-defective HCC1937 and BRCA1-competent MCF-7 breast cancer cell lines were treated with ruthenium(II) complexes. The cytoxoxicity of ruthenium-induced breast cancer cells was evaluated by a real time cellular analyzer (RTCA). Cellular uptake of ruthenium complexes was determined by ICP-MS. Cell cycle progression and apoptosis were assessed using propidium iodide and Annexin V flow cytometry. The N-terminal BRCA1 RING protein was used for conformational and functional studies using circular dichroism and in vitro ubiquitination. HCC1937 cells were significantly more sensitive to the ruthenium complexes than the MDA-MB-231 and MCF-7 cells. Treatment demonstrated a higher degree of cytotoxicity than cisplatin against all three cell lines. Most ruthenium atoms were retained in the nuclear compartment, particularly in HCC1937 cells, after 24 h of incubation, and produced a significant block at the G2/M phase. An increased induction of apoptotic cells as well as an upregulation of p53 mRNA was observed in all tested breast cancer cells. It was of interest that BRCA1 mRNA and replication of BRCA1-defective cells were downregulated. Changes in the conformation and binding constants of ruthenium-BRCA1 adducts were observed, causing inactivation of the RING heterodimer BRCA1/BARD1-mediated E3 ubiquitin ligase activity

  3. Complex permeability and permittivity variation of carbonyl iron rubber in the frequency range of 2 to 18 GHz

    Directory of Open Access Journals (Sweden)

    Adriana Medeiros Gama

    2010-04-01

    Full Text Available The complex dielectric permittivity (e and magnetic permeability (m of Radar Absorbing Materials (RAM based on metallic magnetic particles (carbonyl iron particles embedded in a dielectric matrix (silicon rubber have been studied in the frequency range of 2 to 18 GHz. The relative permeability and permittivity of carbonyl iron-silicon composites for various mass fractions are measured by the transmission/reflection method using a vector network analyzer. The concentration dependence of permittivity and permeability on the frequency is analyzed. In a general way, the results show that e´ parameter shows a more significant variation among the evaluated parameters (e”, m”, m’. The comparison of dielectric and magnetic loss tangents (e”/e” and m”/m’, respectively shows more clearly the variation of both parameters (e and m according to the frequency. It is also observed that higher carbonyl iron content fractions favor both dielectric and magnetic loss tangents.

  4. Femtosecond Fluorescence and Intersystem Crossing in Rhenium(I) Carbonyl-Bipyridine Complexes

    Czech Academy of Sciences Publication Activity Database

    Cannizzo, A.; Blanco-Rodríguez, A. M.; Nahhas, A. E.; Šebera, Jakub; Záliš, Stanislav; Vlček, Antonín; Chergui, M.

    2008-01-01

    Roč. 130, č. 28 (2008), s. 8967-8974 ISSN 0002-7863 R&D Projects: GA MŠk 1P05OC068 Institutional research plan: CEZ:AV0Z40400503 Keywords : rhenium(I) * carbonyl-bipyridine * intersystem crossing Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 8.091, year: 2008

  5. Ruthenium(II)- bipyridyl with extended π-system: Improved thermo ...

    Indian Academy of Sciences (India)

    aInorganic and Physical Chemistry Division, Indian Institute of Chemical Technology, Uppal Road, Tarnaka, ... A new extended thermo-stable high molar extinction coefficient bipyridyl ruthenium(II) complex ... cyanines and metal free organic sensitizers have been ..... Iodide-based ionic liquids are more viscous than.

  6. Ruthenium(ii)-catalyzed olefination via carbonyl reductive cross-coupling.

    Science.gov (United States)

    Wei, Wei; Dai, Xi-Jie; Wang, Haining; Li, Chenchen; Yang, Xiaobo; Li, Chao-Jun

    2017-12-01

    Natural availability of carbonyl groups offers reductive carbonyl coupling tremendous synthetic potential for efficient olefin synthesis, yet the catalytic carbonyl cross-coupling remains largely elusive. We report herein such a reaction, mediated by hydrazine under ruthenium(ii) catalysis. This method enables facile and selective cross-couplings of two unsymmetrical carbonyl compounds in either an intermolecular or intramolecular fashion. Moreover, this chemistry accommodates a variety of substrates, proceeds under mild reaction conditions with good functional group tolerance, and generates stoichiometric benign byproducts. Importantly, the coexistence of KO t Bu and bidentate phosphine dmpe is vital to this transformation.

  7. Highly efficient energy transfer from a carbonyl carotenoid to chlorophyll a in the main light harvesting complex of Chromera velia.

    Science.gov (United States)

    Durchan, Milan; Keşan, Gürkan; Slouf, Václav; Fuciman, Marcel; Staleva, Hristina; Tichý, Josef; Litvín, Radek; Bína, David; Vácha, František; Polívka, Tomáš

    2014-10-01

    We report on energy transfer pathways in the main light-harvesting complex of photosynthetic relative of apicomplexan parasites, Chromera velia. This complex, denoted CLH, belongs to the family of FCP proteins and contains chlorophyll (Chl) a, violaxanthin, and the so far unidentified carbonyl carotenoid related to isofucoxanthin. The overall carotenoid-to-Chl-a energy transfer exhibits efficiency over 90% which is the largest among the FCP-like proteins studied so far. Three spectroscopically different isofucoxanthin-like molecules were identified in CLH, each having slightly different energy transfer efficiency that increases from isofucoxanthin-like molecules absorbing in the blue part of the spectrum to those absorbing in the reddest part of spectrum. Part of the energy transfer from carotenoids proceeds via the ultrafast S2 channel of both the violaxanthin and isofucoxanthin-like carotenoid, but major energy transfer pathway proceeds via the S1/ICT state of the isofucoxanthin-like carotenoid. Two S1/ICT-mediated channels characterized by time constants of ~0.5 and ~4ps were found. For the isofucoxanthin-like carotenoid excited at 480nm the slower channel dominates, while those excited at 540nm employs predominantly the fast 0.5ps channel. Comparing these data with the excited-state properties of the isofucoxanthin-like carotenoid in solution we conclude that, contrary to other members of the FCP family employing carbonyl carotenoids, CLH complex suppresses the charge transfer character of the S1/ICT state of the isofucoxanthin-like carotenoid to achieve the high carotenoid-to-Chl-a energy transfer efficiency. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. (Pyridine)(tetrahydroborato)zinc complex, (Zn(BH4)2(py)), as a new stable, efficient and chemoselective reducing agent for reduction of carbonyl compounds

    International Nuclear Information System (INIS)

    Zeynizadeh, Behzad; Faraji, Fariba

    2003-01-01

    (Pyridine)(tetrahydroborato)zinc complex, (Zn(BH 4 ) 2 (py)), as a stable white solid, was prepared quantitatively by complexation of an equimolar amount of zinc tetrahydroborate and pyridine at room temperature. This reagent can easily reduce variety of carbonyl compounds such as aldehydes, ketones, acyloins, α-diketones and α,β-unsaturated carbonyl compounds to their corresponding alcohols in good to excellent yields. Reduction reactions were performed in ether or THF at room temperature or under reflux conditions. In addition, the chemoselective reduction of aldehydes over ketones was accomplished successfully with this reducing agent

  9. (Pyridine)(tetrahydroborato)zinc complex, (Zn(BH{sub 4}){sub 2}(py)), as a new stable, efficient and chemoselective reducing agent for reduction of carbonyl compounds

    Energy Technology Data Exchange (ETDEWEB)

    Zeynizadeh, Behzad; Faraji, Fariba [Urima Univ., Urima (Iran, Islamic Republic of)

    2003-04-01

    (Pyridine)(tetrahydroborato)zinc complex, (Zn(BH{sub 4}){sub 2}(py)), as a stable white solid, was prepared quantitatively by complexation of an equimolar amount of zinc tetrahydroborate and pyridine at room temperature. This reagent can easily reduce variety of carbonyl compounds such as aldehydes, ketones, acyloins, {alpha}-diketones and {alpha},{beta}-unsaturated carbonyl compounds to their corresponding alcohols in good to excellent yields. Reduction reactions were performed in ether or THF at room temperature or under reflux conditions. In addition, the chemoselective reduction of aldehydes over ketones was accomplished successfully with this reducing agent.

  10. Ruthenium(II) Complexes Containing Lutidine-Derived Pincer CNC Ligands: Synthesis, Structure, and Catalytic Hydrogenation of C-N bonds.

    Science.gov (United States)

    Hernández-Juárez, Martín; López-Serrano, Joaquín; Lara, Patricia; Morales-Cerón, Judith P; Vaquero, Mónica; Álvarez, Eleuterio; Salazar, Verónica; Suárez, Andrés

    2015-05-11

    A series of Ru complexes containing lutidine-derived pincer CNC ligands have been prepared by transmetalation with the corresponding silver-carbene derivatives. Characterization of these derivatives shows both mer and fac coordination of the CNC ligands depending on the wingtips of the N-heterocyclic carbene fragments. In the presence of tBuOK, the Ru-CNC complexes are active in the hydrogenation of a series of imines. In addition, these complexes catalyze the reversible hydrogenation of phenantridine. Detailed NMR spectroscopic studies have shown the capability of the CNC ligand to be deprotonated and get involved in ligand-assisted activation of dihydrogen. More interestingly, upon deprotonation, the Ru-CNC complex 5 e(BF4 ) is able to add aldimines to the metal-ligand framework to yield an amido complex. Finally, investigation of the mechanism of the hydrogenation of imines has been carried out by means of DFT calculations. The calculated mechanism involves outer-sphere stepwise hydrogen transfer to the C-N bond assisted either by the pincer ligand or a second coordinated H2 molecule. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. The effects of linear assembly of two carbazole groups on acid-base and DNA-binding properties of a ruthenium(II) complex

    Science.gov (United States)

    Chen, Xi; Xue, Long-Xin; Ju, Chun-Chuan; Wang, Ke-Zhi

    2013-07-01

    A novel Ru(II) complex of [Ru(bpy)2(Hbcpip)](ClO4)2 {where bpy = 2,2-bipyridine, Hbcpip = 2-(4-(9H-3,9'-bicarbazol-9-yl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline} is synthesized and characterized. Calf-thymus DNA-binding properties of the complex were studied by UV-vis absorption and luminescence titrations, steady-state emission quenching by [Fe(CN)6]4-, DNA competitive binding with ethidium bromide, thermal denaturation and DNA viscosity measurements. The results indicate that the complex partially intercalated into the DNA with a binding constant of (5.5 ± 1.4) × 105 M-1 in buffered 50 mM NaCl. The acid-base properties of the complex were also studied by UV-visible and luminescence spectrophotometric pH titrations, and ground- and excited-state acidity ionization constant values were derived.

  12. Carbonyl Activation by Borane Lewis Acid Complexation: Transition States of H2 Splitting at the Activated Carbonyl Carbon Atom in a Lewis Basic Solvent and the Proton-Transfer Dynamics of the Boroalkoxide Intermediate.

    Science.gov (United States)

    Heshmat, Mojgan; Privalov, Timofei

    2017-07-06

    By using transition-state (TS) calculations, we examined how Lewis acid (LA) complexation activates carbonyl compounds in the context of hydrogenation of carbonyl compounds by H 2 in Lewis basic (ethereal) solvents containing borane LAs of the type (C 6 F 5 ) 3 B. According to our calculations, LA complexation does not activate a ketone sufficiently enough for the direct addition of H 2 to the O=C unsaturated bond; but, calculations indicate a possibly facile heterolytic cleavage of H 2 at the activated and thus sufficiently Lewis acidic carbonyl carbon atom with the assistance of the Lewis basic solvent (i.e., 1,4-dioxane or THF). For the solvent-assisted H 2 splitting at the carbonyl carbon atom of (C 6 F 5 ) 3 B adducts with different ketones, a number of TSs are computed and the obtained results are related to insights from experiment. By using the Born-Oppenheimer molecular dynamics with the DFT for electronic structure calculations, the evolution of the (C 6 F 5 ) 3 B-alkoxide ionic intermediate and the proton transfer to the alkoxide oxygen atom were investigated. The results indicate a plausible hydrogenation mechanism with a LA, that is, (C 6 F 5 ) 3 B, as a catalyst, namely, 1) the step of H 2 cleavage that involves a Lewis basic solvent molecule plus the carbonyl carbon atom of thermodynamically stable and experimentally identifiable (C 6 F 5 ) 3 B-ketone adducts in which (C 6 F 5 ) 3 B is the "Lewis acid promoter", 2) the transfer of the solvent-bound proton to the oxygen atom of the (C 6 F 5 ) 3 B-alkoxide intermediate giving the (C 6 F 5 ) 3 B-alcohol adduct, and 3) the S N 2-style displacement of the alcohol by a ketone or a Lewis basic solvent molecule. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Microwave spectrum, dipole moment, and internal dynamics of the methyl fluoride-carbonyl sulfide weakly bound complex.

    Science.gov (United States)

    Serafin, Michal M; Peebles, Sean A

    2008-02-21

    Rotational spectra for the normal and four isotopically substituted species of the 1:1 complex between methyl fluoride (H3CF) and carbonyl sulfide (OCS) have been measured using Fourier-transform microwave spectroscopy in the 5-16 GHz frequency region. The observed spectra fit well to a semirigid Watson Hamiltonian, and an analysis of the rotational constants has allowed a structure to be determined for this complex. The dipole moment vectors of the H3CF and OCS monomers are aligned approximately antiparallel with a C...C separation of 3.75(3) A and with an ab plane of symmetry. The values of the Pcc planar moments were found to be considerably different from the expected rigid values for all isotopologues. An estimate of approximately 14.5(50) cm-1 for the internal rotation barrier of the CH3 group with respect to the framework of the complex has been made using the Pcc values for the H3CF-OCS and D3CF-OCS isotopic species. Two structures, very close in energy and approximately related by a 60 degrees rotation about the C3 axis of the methyl fluoride, were identified by ab initio calculations at the MP2/6-311++G(2d,2p) level and provide reasonable agreement with the experimental rotational constants and dipole moment components.

  14. Study of electron spectra of lanthanide complexes with carbonyl-containing reagents

    International Nuclear Information System (INIS)

    Tishchenko, M.A.; Gerasimenko, G.I.; Markina, A.I.; Tishchenko, V.V.; Rybalka, V.B.; Tsitko, A.S.

    1990-01-01

    Interaction of lanthanide complexes (Ln=Er, Nd, Ho) of 2-acetylindandione-1,3 with polyphenols was investigated by the methods of electron spectroscopy. Position, intensity, oscillator strengths of supersensitive transitions, formed in the system of different-ligand complexes were determined. 10 refs.; 4 figs.; 3 tabs

  15. THE SYNTHESIS OF BIOCONJUGATE BASED ON RHENIUM(I CARBONYL COMPLEX FOR VISUALIZATION OF PATHOLOGICAL PROCESS

    Directory of Open Access Journals (Sweden)

    K. O. Piletska

    2017-03-01

    Full Text Available Tricarbonyl rhenium(I complexes have a great potential like biomarkers. It is caused their biological stability, low toxicity, large Stokes shifts, and long luminescence lifetimes. Rhenium tricarbonyl complexes fac-[Re(CO3(N^N], where N^N is a ligand with low π* orbitals are excellent candidates as imaging dyes. The method of obtaining potential biomarkers based on tricarbonyl rhenium(I complex with a 4-methyl-2,2’-bipyridine-4’-carboxylate by the addition of biomolecules by peptide synthesis was developed. The new complex [Re(CO3MebpyCOOHBr] was synthesized, composition and structure of which were established by mass spectrometry, IR and NMR spectroscopy. A selective attachment of receptor peptide enkephalin to complex [Re(CO3(MebpyCOOHBr] was performed. The formation of a new compound and its structure has been confirmed by HPLC and mass spectral analysis. The method which has been developed allows to connect various peptides to rhenium(I complex in the solution.

  16. Preparations and characterization of some carbonyl-(1-cyanoethyl)ruthenium(II) complexes

    Energy Technology Data Exchange (ETDEWEB)

    Hiraki, Katsuma; Ochi, Naoyuki; Kitamura, Tsuneyuki; Sasada, Yoko [Nagasaki Univ. (Japan); Shinoda, Sumio

    1982-08-01

    A hydridoruthenium(II) complex (RuClH(CO)(PPh/sub 3/)/sub 3/) reacted easily with acrylonitrile and fumaronitrile to give chloro-bridged binuclear (1-cyanoethyl)ruthenium(II) complexes, ((Ru(MeCHCN)Cl(CO)(PPh/sub 3/)/sub 2/)/sub 2/) (2) and ((Ru(NCCH/sub 2/CHCN)Cl(CO)(PPh/sub 3/)/sub 2/)/sub 2/), respectively. Complex 2 reacted with 4-picoline (pic), Na(BHPz/sub 3/) (Pz = 1-pyrazolyl), Na(BPz/sub 4/), and Na(Et/sub 2/NCS/sub 2/).3H/sub 2/O to afford the corresponding (1-cyanoethyl)ruthenium(II) complexes, ((Ru(MeCHCN)Cl(CO)(pic)(PPh/sub 3/))/sub 2/) (3), (Ru(MeCHCN)(BHPz/sub 3/)(CO)(PPh/sub 3/)) (accompanied by a small amount of (Ru/sub 2/(MeCHCN)/sub 2/Cl(BHPz/sub 3/)(CO)/sub 2/(PPh/sub 3/)/sub 4/)), (Ru/sub 2/(MeCHCN)/sub 2/Cl(BPz/sub 4/)(CO)/sub 2/(PPh/sub 3/)/sub 2/), and Na(Ru(MeCHCN)Cl(Et/sub 2/NCS/sub 2/)(CO)(PPh/sub 3/)), respectively. Complex 3 reacted with thallium (I) acetylacetonate (Tl(acac)), resulting in the formation of ((Ru(MeCHCN)(acac)(CO)(PPh/sub 3/))/sub 2/) and (Ru(MeCHCN)(acad)(CO)(pic)(PPh/sub 3/)). These new complexes were characterized by means of elemental analysis and spectroscopic data. The diastereoisomerism was also discussed as regards these (1-cyanoethyl)ruthenium(II) complexes.

  17. Defects in tor regulatory complexes retard aging and carbonyl/oxidative stress development in yeast Sассharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    B. V. Homza

    2014-02-01

    Full Text Available TOR signaling pathway first described in yeast S. сerevisiae is the highly conserved regulator of eukaryotic cell growth, aging and stress resistance. The effect of nitrogen sources, in particular amino acids, on the activity of TOR signaling pathway is well studied, however its relation to carbohydrates is poor understood. The aim of the present study is expanding of our understanding of potential role of TOR regulatory complexes in development of carbonyl/oxidative stress that can result from yeast cultivation on glucose and fructose. It has been shown that the level of α-dicarbonyl compounds and protein carbonyl groups increased with time of yeast cultivation and was higher in cells grown on fructose that demonstrated their accelerated aging and carbonyl/oxidative stress development as compared with cells grown on glucose. The strains defective in TOR proteins cultivated in the presence of glucose as well as fructose demonstrated lower markers of the stress and aging than parental strain. Thus these data confirmed the previous conclusion on fructose more potent ability to cause carbonyl/oxidative stress and accelerated aging in S. cerevisiae as compared with glucose. However, defects in TOR regulatory complexes retard aging and development of the stress in yeast independent on the type of carbohydrate in the cultivation medium.

  18. Synthesis, structure and photoluminescence of novel lanthanide (Tb(III), Gd(III)) complexes with 6-diphenylamine carbonyl 2-pyridine carboxylate

    International Nuclear Information System (INIS)

    An Baoli; Gong Menglian; Cheah, Kok-Wai; Wong, Wai-Kwok; Zhang Jiming

    2004-01-01

    A novel organic ligand, 6-diphenylamine carbonyl 2-pyridine carboxylic acid (HDPAP), and the corresponding lanthanide complexes, tris(6-diphenylamine carbonyl 2-pyridine carboxylato) terbium(III) (Tb-DPAP) and tris(6-diphenylamine carbonyl 2-pyridine carboxylato) gadolinium(III) (Gd-DPAP) have been designed and synthesized. The crystal structure and photoluminescence of Tb-DPAP and Gd-DPAP have been studied. The results showed that the lanthanide complexes have electroneutral structures, and the solid terbium complex emits characteristic green fluorescence of Tb(III) ions at room temperature while the gadolinium complex emits the DPAP ligand phosphorescence. The lowest triplet level of DPAP ligand was calculated from the phosphorescence spectrum of Gd-DPAP in N,N-dimethyl formamide (DMF) dilute solution determined at 77 K, and the energy transfer mechanisms in the lanthanide complexes were discussed. The lifetimes of the 5 D 4 levels of Tb 3+ ions in the terbium complex were examined using time-resolved spectroscopy, and the values are 0.0153±0.0001 ms for solid Tb(DPAP) 3 ·11.5H 2 O and 0.074±0.007 ms for 2.5x10 -5 mol/l Tb-DPAP ethanol solution

  19. Fischer aminocarbene complexes of chromium and iron: Anomalous electrochemical reduction of p-carbonyl substituted derivatives

    Czech Academy of Sciences Publication Activity Database

    Hoskovcová, I.; Zvěřinová, R.; Roháčová, J.; Dvořák, D.; Tobrman, T.; Záliš, Stanislav; Ludvík, Jiří

    2011-01-01

    Roč. 56, č. 19 (2011), s. 6853-6859 ISSN 0013-4686 R&D Projects: GA AV ČR IAA400400813 Institutional research plan: CEZ:AV0Z40400503 Keywords : DFT calculations * electrochemistry * Fischer aminocarbene complexes Subject RIV: CG - Electrochemistry Impact factor: 3.832, year: 2011

  20. Preparation and bioevaluation of 99mTc-carbonyl complex of guanine

    International Nuclear Information System (INIS)

    Cigdem Ichedef; Serap Teksoez; Kamile Senocak; Eser Ucar; Ayfer Yurt Kilcar

    2011-01-01

    The aim of this study is to prepare radiolabeled guanine with 99m Tc(CO) 3 + core. For this purpose, guanine has been radiolabeled with 99m Tc(CO) 3 + core. Quality control study of radiolabeled guanine molecule with 99m Tc(CO) 3 + core was performed by thin layer radio chromatography (TLRC) and high performance liquid radio chromatography (HPLRC). The results showed that the radiolabeling yield was quite high (94 ± 3%). Beside that 99m Tc(CO) 3 -Gua complex has showed good in vitro stability during the 24 h period. Radiopharmaceutical potential of this complex was evaluated in Wistar Albino Rats. It was concluded that 99m Tc(CO) 3 -Gua could be used as a nucleotide radiopharmaceutical for in vivo applications. (author)

  1. Efficient light-harvesting using non-carbonyl carotenoids: Energy transfer dynamics in the VCP complex from Nannochloropsis oceanica.

    Science.gov (United States)

    Keşan, Gürkan; Litvín, Radek; Bína, David; Durchan, Milan; Šlouf, Václav; Polívka, Tomáš

    2016-04-01

    Violaxanthin-chlorophyll a protein (VCP) from Nannochloropsis oceanica is a Chl a-only member of the LHC family of light-harvesting proteins. VCP binds carotenoids violaxanthin (Vio), vaucheriaxanthin (Vau), and vaucheriaxanthin-ester (Vau-ester). Here we report on energy transfer pathways in the VCP complex. The overall carotenoid-to-Chla energy transfer has efficiency over 90%. Based on their energy transfer properties, the carotenoids in VCP can be divided into two groups; blue carotenoids with the lowest energy absorption band around 480nm and red carotenoids with absorption extended up to 530nm. Both carotenoid groups transfer energy efficiently from their S2 states, reaching efficiencies of ~70% (blue) and ~60% (red). The S1 pathway, however, is efficient only for the red carotenoid pool for which two S1 routes characterized by 0.33 and 2.4ps time constants were identified. For the blue carotenoids the S1-mediated pathway is represented only by a minor route likely involving a hot S1 state. The relaxed S1 state of blue carotenoids decays to the ground state within 21ps. Presence of a fraction of non-transferring red carotenoids with the S1 lifetime of 13ps indicates some specific carotenoid-protein interaction that must shorten the intrinsic S1 lifetime of Vio and/or Vau whose S1 lifetimes in methanol are 26 and 29ps, respectively. The VCP complex from N. oceanica is the first example of a light-harvesting complex binding only non-carbonyl carotenoids with carotenoid-to-chlorophyll energy transfer efficiency over 90%. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Lack of FTSH4 Protease Affects Protein Carbonylation, Mitochondrial Morphology, and Phospholipid Content in Mitochondria of Arabidopsis: New Insights into a Complex Interplay.

    Science.gov (United States)

    Smakowska, Elwira; Skibior-Blaszczyk, Renata; Czarna, Malgorzata; Kolodziejczak, Marta; Kwasniak-Owczarek, Malgorzata; Parys, Katarzyna; Funk, Christiane; Janska, Hanna

    2016-08-01

    FTSH4 is one of the inner membrane-embedded ATP-dependent metalloproteases in mitochondria of Arabidopsis (Arabidopsis thaliana). In mutants impaired to express FTSH4, carbonylated proteins accumulated and leaf morphology was altered when grown under a short-day photoperiod, at 22°C, and a long-day photoperiod, at 30°C. To provide better insight into the function of FTSH4, we compared the mitochondrial proteomes and oxyproteomes of two ftsh4 mutants and wild-type plants grown under conditions inducing the phenotypic alterations. Numerous proteins from various submitochondrial compartments were observed to be carbonylated in the ftsh4 mutants, indicating a widespread oxidative stress. One of the reasons for the accumulation of carbonylated proteins in ftsh4 was the limited ATP-dependent proteolytic capacity of ftsh4 mitochondria, arising from insufficient ATP amount, probably as a result of an impaired oxidative phosphorylation (OXPHOS), especially complex V. In ftsh4, we further observed giant, spherical mitochondria coexisting among normal ones. Both effects, the increased number of abnormal mitochondria and the decreased stability/activity of the OXPHOS complexes, were probably caused by the lower amount of the mitochondrial membrane phospholipid cardiolipin. We postulate that the reduced cardiolipin content in ftsh4 mitochondria leads to perturbations within the OXPHOS complexes, generating more reactive oxygen species and less ATP, and to the deregulation of mitochondrial dynamics, causing in consequence the accumulation of oxidative damage. © 2016 American Society of Plant Biologists. All Rights Reserved.

  3. Solid-state thermolysis of a fac-rhenium(I) carbonyl complex with a redox non-innocent pincer ligand.

    Science.gov (United States)

    Jurca, Titel; Chen, Wen-Ching; Michel, Sheila; Korobkov, Ilia; Ong, Tiow-Gan; Richeson, Darrin S

    2013-03-25

    The development of rhenium(I) chemistry has been restricted by the limited structural and electronic variability of the common pseudo-octahedral products fac-[ReX(CO)3L2] (L2 = α-diimine). We address this constraint by first preparing the bidentate bis(imino)pyridine complexes [(2,6-{2,6-Me2C6H3N=CPh}2C5H3N)Re(CO)3X] (X = Cl 2, Br 3), which were characterized by spectroscopic and X-ray crystallographic means, and then converting these species into tridentate pincer ligand compounds, [(2,6-{2,6-Me2C6H3N=CPh}2C5H3N)Re(CO)2X] (X = Cl 4, Br 5). This transformation was performed in the solid-state by controlled heating of 2 or 3 above 200 °C in a tube furnace under a flow of nitrogen gas, giving excellent yields (≥95 %). Compounds 4 and 5 define a new coordination environment for rhenium(I) carbonyl chemistry where the metal center is supported by a planar, tridentate pincer-coordinated bis(imino)pyridine ligand. The basic photophysical features of these compounds show significant elaboration in both number and intensity of the d-π* transitions observed in the UV/Vis spec tra relative to the bidentate starting materials, and these spectra were analyzed using time-dependent DFT computations. The redox nature of the bis(imino)pyridine ligand in compounds 2 and 4 was examined by electrochemical analysis, which showed two ligand reduction events and demonstrated that the ligand reduction shifts to a more positive potential when going from bidentate 2 to tridentate 4 (+160 mV for the first reduction step and +90 mV for the second). These observations indicate an increase in electrostatic stabilization of the reduced ligand in the tridentate conformation. Elaboration on this synthetic methodology documented its generality through the preparation of the pseudo-octahedral rhenium(I) triflate complex [(2,6-{2,6-Me2C6H3N=CPh}2C5H3N)Re(CO)2OTf] (7, 93 % yield). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Highly efficient energy transfer from a carbonyl carotenoid to chlorophyll a in the main light harvesting complex of Chromera velia

    Czech Academy of Sciences Publication Activity Database

    Durchan, Milan; Kesan, G.; Šlouf, M.; Fuciman, M.; Staleva, H.; Tichý, Josef; Litvín, Radek; Bína, David; Vácha, František; Polívka, Tomáš

    2014-01-01

    Roč. 1837, č. 10 (2014), s. 1748-1755 ISSN 0005-2728 R&D Projects: GA ČR(CZ) GAP205/11/1164; GA ČR GBP501/12/G055 Institutional support: RVO:60077344 Keywords : Energy transfer * Light-harvesting * Carbonyl carotenoids Subject RIV: BO - Biophysics Impact factor: 5.353, year: 2014

  5. THE METAL CARBONYLS.

    Science.gov (United States)

    Blanchard, A A

    1941-10-03

    When the metal carbonyls were first discovered, their properties were startling because they seemed to violate nearly all the previously recognized generalizations of chemistry. Even to-day the existence of the carbonyls is not particularly emphasized in elementary courses of chemistry because it is rather hard to reconcile them with the first presentations of the generalizations of chemistry. Nevertheless, as the student progresses deeper into the knowledge of chemistry it becomes desirable to include the knowledge of the carbonyls both because they become more comprehensible when viewed in the light of Werner's system of coordination and because they themselves contribute to the comprehension of the Werner theory. As long ago as 1931, Reiff in his discussion of cobalt nitrosyl carbonyl recognized the correlation between the effective atomic number and the volatility of carbonyls. A more recent study of charged Werner coordination complexes, that is, of complex ions, has shown a similar role of the effective atomic number. We are standing on fairly firm ground when we point out the correlation between E.A.N. and the volatility of the carbonyl complexes and the existence of complex ions. Be it noted that we have made no postulates as to the arrangement of the electrons in quantum levels. In the inert gases the outer principal quantum group is supposed always to contain eight electrons. In the carbonyls and other Werner complexes there is no compelling reason to suppose that the electrons in the coordinating layer, be this layer of eight, ten, twelve or sixteen electrons, are not all at the same energy level. Although we have confined our discussion almost exclusively to the property of volatility, the carbonyls are very interesting from the standpoint of several other properties, for example, magnetic susceptibility and dielectric constant. Enthusiasts in the interpretation of such properties try to draw conclusions as to the condition of the electrons, sometimes

  6. Synthesis and characterization of bisoxazolines- and pybox-copper(II) complexes and their application in the coupling of α-carbonyls with functionalized amines

    KAUST Repository

    Jia, Weiguo

    2014-01-01

    Binuclear complexes [{(DMOX)CuCl}2(μ-Cl)2] (1), mononuclear complexes [(DMOX)CuBr2] (2) (DMOX = 4,5-dihydro-2-(4,5- dihydro-4,4-dimethyloxazol-2-yl)-4,4-dimethyloxazole) and the pybox Cu(ii) complex [(Dm-Pybox)CuBr2] (3) (Dm-Pybox = 2,6-bis[4′,4′- dimethyloxazolin-2′-yl]pyridine) were obtained by reactions of CuX 2 (X = Cl, Br) with DMOX and Dm-Pybox ligands, respectively. The molecular structures of 1, 2 and 3 have been determined by single-crystal X-ray diffraction analyses. The complexes 2 and 3 are efficient in catalyzing α-amination of ketones and esters through α-bromo carbonyl intermediate. The procedures are environmentally benign methods using molecular oxygen as an oxidant with water as the only byproduct. This journal is © the Partner Organisations 2014.

  7. Ruthenium(ii)-catalyzed olefination via carbonyl reductive cross-coupling† †Electronic supplementary information (ESI) available: Experimental details. See DOI: 10.1039/c7sc04207h

    Science.gov (United States)

    Wei, Wei; Dai, Xi-Jie; Wang, Haining; Li, Chenchen; Yang, Xiaobo

    2017-01-01

    Natural availability of carbonyl groups offers reductive carbonyl coupling tremendous synthetic potential for efficient olefin synthesis, yet the catalytic carbonyl cross-coupling remains largely elusive. We report herein such a reaction, mediated by hydrazine under ruthenium(ii) catalysis. This method enables facile and selective cross-couplings of two unsymmetrical carbonyl compounds in either an intermolecular or intramolecular fashion. Moreover, this chemistry accommodates a variety of substrates, proceeds under mild reaction conditions with good functional group tolerance, and generates stoichiometric benign byproducts. Importantly, the coexistence of KOtBu and bidentate phosphine dmpe is vital to this transformation. PMID:29568466

  8. Reactivity of Fe3(CO)12 with Alkynes R-C≡-C-R':Syntheses and Crystal Structures of Substituted Cyclic Ketones and Carbonyl Iron Complexes

    Institute of Scientific and Technical Information of China (English)

    SUO Quan-Ling; WU Le; SU Qian; ZHU Ning; GAO Yuan-Yuan; HONG Hai-Long; XIE Rui-Jun; HAN Li-Min

    2017-01-01

    The reactivity of carbonyl iron cluster with alkynes has been studied by the thermal reaction of Fe3(CO)12 with R-C≡C-R'(R =Fc (Ferrocenyl);R'=Ph (Phenyl),Fc,H).The hexacarbonyldiiron cluster with ferracyclopentadiene ring (μ2,η4-C4Ph4)Fe2(CO)6 (1) and one tetraphenyl substituted cyclopentadienone (Ph4C4CO) (2) were simultaneously obtained by the reaction of Fe3(CO)12 with alkyne (Ph-C≡C-Ph).Only one ferrole cluster (μ2,η4-C4Fc2H2)Fe2(CO)6 (3) was separated by using Fc-C≡C-H as alkyne.One tri-carbonyl iron complex (η4-C4Fc4CO)Fe(CO)3 (4) and an unexpected new cyclic ketone compound 2,2,4,5-tetraferrocenylcyclopenta-4-en-l,3-di-one [Fc4C3(CO)2] (5) were obtained by using Fc-C≡C-Fc as alkyne.A new complex (η4-2,4-diphenyl-3,5-diferrocenylcyclopenta-2,4-dien-l-one)-tricarbonyl iron (η4-C4Ph2Fc2CO)Fe(CO)3 (6)was synthesized by the reaction of Fe3(CO)12 with Fc-C≡C-Ph.The structures of compounds 1~6 were determined by X-ray single-crystal diffraction and spectroscopic characterization.The crystal structures of two new compounds 5 and 6 were analyzed.Our experimental results reveal the structural models of the reaction products are affected by the kinds of substituents from alkynes R-C≡C-R'.

  9. Synthesis and characterization of rhodium(I) complexes with P-N donor ligands and their catalytic application in transfer hydrogenation of carbonyl group

    Energy Technology Data Exchange (ETDEWEB)

    Barah, Geetika; Sarmah, Podma Poliov; Boruah, Devajani [Dept. of Chemistry, Dibrugarh University, Dibrugarh (India)

    2015-04-15

    Three rhodium(I) complexes of the types [Rh(COE)Cl(η{sup 2}-L)] (1a,1b) and [RhCl(η{sup 2}-L) (η{sup 1}-L)] (1c), where L = P⁓N donor ligands 2-[2-(diphenylphosphino) ethyl]pyridine, (PPh{sub 2}Etpy) (a), 2-(diphenylphosphino)pyridine (PPh{sub 2}py) (b), and 3-(diphenylphosphino)-1-propylamine (PPh{sub 2}(CH{sub 2}){sub 3}NH{sub 2}) (c), have been synthesized by reacting [Rh(coe){sub 2}Cl]{sub 2} with the respective ligands in 1:2 molar ratio for 1a, 1b and 1:4 molar ratio for 1c in DCM under refluxing condition. The complexes were characterized using different analytical techniques such as FT-IR, ESI(+) mass spectrometry, {sup 1}H and {sup 31}P{"1H} NMR spectrometry, conductivity measurements, and melting point determination. The synthesized complexes were found to exhibit good catalytic activity for the transfer hydrogenation of carbonyl compounds to corresponding alcohols with high conversion rate.

  10. Unusual saccharin-N,O (carbonyl) coordination in mixed-ligand copper(II) complexes: Synthesis, X-ray crystallography and biological activity

    Science.gov (United States)

    Mokhtaruddin, Nur Shuhada Mohd; Yusof, Enis Nadia Md; Ravoof, Thahira B. S. A.; Tiekink, Edward R. T.; Veerakumarasivam, Abhi; Tahir, Mohamed Ibrahim Mohamed

    2017-07-01

    Three tridentate Schiff bases containing N and S donor atoms were synthesized via the condensation reaction between S-2-methylbenzyldithiocarbazate with 2-acetyl-4-methylpyridine (S2APH); 4-methyl-3-thiosemicarbazide with 2-acetylpyridine (MT2APH) and 4-ethyl-3-thiosemicarbazide with 2-acetylpyridine (ET2APH). Three new, binuclear and mixed-ligand copper(II) complexes with the general formula, [Cu(sac)(L)]2 (sac = saccharinate anion; L = anion of the Schiff base) were then synthesized, and subsequently characterized by IR and UV/Vis spectroscopy as well as by molar conductivity and magnetic susceptibility measurements. The Schiff bases were also spectroscopically characterized using NMR and MS to further confirm their structures. The spectroscopic data indicated that the Schiff bases behaved as a tridentate NNS donor ligands coordinating via the pyridyl-nitrogen, azomethine-nitrogen and thiolate-sulphur atoms. Magnetic data indicated a square pyramidal environment for the complexes and the conductivity values showed that the complexes were essentially non-electrolytes in DMSO. The X-ray crystallographic analysis of one complex, [Cu(sac)(S2AP)]2 showed that the Cu(II) atom was coordinated to the thiolate-S, azomethine-N and pyridyl-N donors of the S2AP Schiff base and to the saccharinate-N from one anion, as well as to the carbonyl-O atom from a symmetry related saccharinate anion yielding a centrosymmetric binuclear complex with a penta-coordinate, square pyramidal geometry. All the copper(II) saccharinate complexes were found to display strong cytotoxic activity against the MCF-7 and MDA-MB-231 human breast cancer cell lines.

  11. Protein carbonylation in plants

    DEFF Research Database (Denmark)

    Møller, Ian Max; Havelund, Jesper; Rogowska-Wrzesinska, Adelina

    2017-01-01

    This chapter provides an overview of the current knowledge on protein carbonylation in plants and its role in plant physiology. It starts with a brief outline of the turnover and production sites of reactive oxygen species (ROS) in plants and the causes of protein carbonylation. This is followed...... by a description of the methods used to study protein carbonylation in plants, which is also very brief as the methods are similar to those used in studies on animals. The chapter also focuses on protein carbonylation in plants in general and in mitochondria and in seeds in particular, as case stories where...... specific carbonylated proteins have been identified. Protein carbonylation appears to accumulate at all stages of seed development and germination investigated to date. In some cases, such as seed aging, it is probably simply an accumulation of oxidative damage. However, in other cases protein...

  12. Ruthenium, osmium and rhodium complexes of polypyridyl ligands ...

    Indian Academy of Sciences (India)

    Unknown

    Discipline of Silicates and Catalysis, Central Salt and Marine Chemicals ... However, synthetic methods have also been developed to prepare complexes with ... 3.2 Synthesis and characterisation of ruthenium(II) and osmium(II) complexes18, ...

  13. Synthesis, spectroscopic, DFT calculations and biological activity studies of ruthenium carbonyl complexes with 2-picolinic acid and a secondary ligand

    Science.gov (United States)

    Shohayeb, Shahera M.; Mohamed, Rania G.; Moustafa, H.; El-Medani, Samir M.

    2016-09-01

    Thermal reaction of [Ru3(CO)12] with 2-picolinic acid (Hpic) in the absence and presence of a secondary ligand (pyridine, Py, bipyridine, Bipy, or thiourea, Tu) was investigated. Four complexes with molecular formulae: [Ru(CO)3(Hpic)], 1, [Ru2(CO)5(Hpic)(Py)], 2, [Ru2(CO)5(Hpic)(Tu)], 3 and [Ru2(CO)4(Hpic)(Bipy)], 4, were isolated. All complexes were characterized based on elemental analyses, IR, 1H NMR, magnetic studies, mass spectrometry and thermal analysis. The ligand and its complexes have been screened for antibacterial activities. Density Functional Theory (DFT) calculations at the B3LYP/6-311G (d,p)_ level of theory have been carried out to investigate the equilibrium geometry of the ligands. The optimized geometry parameters of the complexes were evaluated using B3LYP method and LANL2DZ basis set. The extent of natural charge population (core, valence and rydberg), exact electronic configuration, total Lewis and total non-Lewis are estimated and discussed in terms of natural bond orbitals (NBO) analysis.

  14. Efficient light-harvesting using non-carbonyl carotenoids: Energy transfer dynamics in the VCP complex from Nannochloropsis oceanica

    Czech Academy of Sciences Publication Activity Database

    Kesan, G.; Litvín, Radek; Bína, David; Durchan, Milan; Šlouf, V.; Polívka, Tomáš

    2016-01-01

    Roč. 1857, č. 4 (2016), s. 370-379 ISSN 0005-2728 R&D Projects: GA ČR(CZ) GAP205/11/1164; GA ČR GBP501/12/G055; GA ČR(CZ) GP14-01377P Institutional support: RVO:60077344 Keywords : Carotenoids * Energy transfer * Light-harvesting complex Subject RIV: BO - Biophysics Impact factor: 4.932, year: 2016

  15. A method for hydrogenating and carbonylizing unsaturated compounds in the presence of catalysts based on phosphine and metal complexes

    Energy Technology Data Exchange (ETDEWEB)

    Briggs, J C; Dyer, G

    1982-12-22

    The hydrogenation of unsaturated organic compounds or the attachment to them of CO is accomplished with contact with a synthesis gas in the presence of a stereospecific catalyst (Kt), a compound of a metal of the platinum group (preferably Rhodium, but also Platinum, Palladium, Ruthenium or Iridium) and an asymmetrical bis-phosphine of the formula A-(CH2)n-B, where A and B are phosphine groups. R2P and R'2P or RRhP, where R is an aryl radical, R' is aralkyl, alcarylic or alkyl radical, n = 1 to 10, or an asymmetrical monophosphine of the formula R2-R'P. The complex compound also includes Hydrogen, CO and (or) halogen (preferably Chlorine) as ligands. The physical properties of the obtained complex compounds of the carbonylchlorbisphosphines or Rh are presented: trans-(RhC1-(CO)(Ph2P(CH2)6PPh2))2; trans-(RhC1(CO)(C2H5PhP-(CH2)6PPh2))2; trans-(RhC1(CO)(cycloC6H11PhP(CH2)6-PPh2))2; trans-(RhC1(CO)(C2H5PhP(CH2)4PPh2)2; trans-(RhC1(CO)(C2H5PhP(Ch2))2 and PhC1(CO)4(p-C6H4CH2)2P(Ch2)6PPh2). The isolated complexes are light yellow crystalline substances.

  16. Merging Iron Catalysis and Biocatalysis-Iron Carbonyl Complexes as Efficient Hydrogen Autotransfer Catalysts in Dynamic Kinetic Resolutions

    KAUST Repository

    El-Sepelgy, Osama

    2016-09-29

    A dual catalytic iron/lipase system has been developed and applied in the dynamic kinetic resolution of benzylic and aliphatic secondary alcohols. A detailed study of the Knölker-type iron complexes demonstrated the hydrogen autotransfer of alcohols to proceed under mild reaction conditions and allowed the combination with the enzymatic resolution. Different racemic alcohols were efficiently converted to chiral acetates in good yields and with excellent enantioselectivities. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

  17. Merging Iron Catalysis and Biocatalysis-Iron Carbonyl Complexes as Efficient Hydrogen Autotransfer Catalysts in Dynamic Kinetic Resolutions

    KAUST Repository

    El-Sepelgy, Osama; Alandini, Nurtalya; Rueping, Magnus

    2016-01-01

    A dual catalytic iron/lipase system has been developed and applied in the dynamic kinetic resolution of benzylic and aliphatic secondary alcohols. A detailed study of the Knölker-type iron complexes demonstrated the hydrogen autotransfer of alcohols to proceed under mild reaction conditions and allowed the combination with the enzymatic resolution. Different racemic alcohols were efficiently converted to chiral acetates in good yields and with excellent enantioselectivities. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

  18. Kinetics of carbonyl reductase from human brain.

    OpenAIRE

    Bohren, K M; von Wartburg, J P; Wermuth, B

    1987-01-01

    Initial-rate analysis of the carbonyl reductase-catalysed reduction of menadione by NADPH gave families of straight lines in double-reciprocal plots consistent with a sequential mechanism being obeyed. The fluorescence of NADPH was increased up to 7-fold with a concomitant shift of the emission maximum towards lower wavelength in the presence of carbonyl reductase, and both NADPH and NADP+ caused quenching of the enzyme fluorescence, indicating formation of a binary enzyme-coenzyme complex. D...

  19. Synthesis of a ruthenium(II) bipyridyl complex coordinated by a functionalized Schiff base ligand: characterization, spectroscopic and isothermal titration calorimetry measurements of M2+ binding and sensing (M2+=Ca2+, Mg2+).

    Science.gov (United States)

    Dixit, Namrata; Mishra, Lallan; Mustafi, Sourajit M; Chary, Kandala V R; Houjou, Hirohiko

    2009-07-01

    Bis-[methylsalicylidine-4'benzoic acid]-ethylene (LH2) complexed with cis-Ru(bpy)2Cl(2).2H2O provides a complex of composition [Ru(bpy)2L].2NH4PF6 (1), which has been characterized spectroscopically. Its binding behaviour towards Mg2+ and Ca2+ ions is monitored using 1H NMR titration, isothermal titration calorimetry (ITC) and luminescence microscopy. The luminescent ruthenium complex binds Ca2+ in a more selective manner as compared to Mg2+.

  20. Protein Carbonylation and Adipocyte Mitochondrial Function*

    Science.gov (United States)

    Curtis, Jessica M.; Hahn, Wendy S.; Stone, Matthew D.; Inda, Jacob J.; Droullard, David J.; Kuzmicic, Jovan P.; Donoghue, Margaret A.; Long, Eric K.; Armien, Anibal G.; Lavandero, Sergio; Arriaga, Edgar; Griffin, Timothy J.; Bernlohr, David A.

    2012-01-01

    Carbonylation is the covalent, non-reversible modification of the side chains of cysteine, histidine, and lysine residues by lipid peroxidation end products such as 4-hydroxy- and 4-oxononenal. In adipose tissue the effects of such modifications are associated with increased oxidative stress and metabolic dysregulation centered on mitochondrial energy metabolism. To address the role of protein carbonylation in the pathogenesis of mitochondrial dysfunction, quantitative proteomics was employed to identify specific targets of carbonylation in GSTA4-silenced or overexpressing 3T3-L1 adipocytes. GSTA4-silenced adipocytes displayed elevated carbonylation of several key mitochondrial proteins including the phosphate carrier protein, NADH dehydrogenase 1α subcomplexes 2 and 3, translocase of inner mitochondrial membrane 50, and valyl-tRNA synthetase. Elevated protein carbonylation is accompanied by diminished complex I activity, impaired respiration, increased superoxide production, and a reduction in membrane potential without changes in mitochondrial number, area, or density. Silencing of the phosphate carrier or NADH dehydrogenase 1α subcomplexes 2 or 3 in 3T3-L1 cells results in decreased basal and maximal respiration. These results suggest that protein carbonylation plays a major instigating role in cytokine-dependent mitochondrial dysfunction and may be linked to the development of insulin resistance in the adipocyte. PMID:22822087

  1. Protein carbonylation and adipocyte mitochondrial function.

    Science.gov (United States)

    Curtis, Jessica M; Hahn, Wendy S; Stone, Matthew D; Inda, Jacob J; Droullard, David J; Kuzmicic, Jovan P; Donoghue, Margaret A; Long, Eric K; Armien, Anibal G; Lavandero, Sergio; Arriaga, Edgar; Griffin, Timothy J; Bernlohr, David A

    2012-09-21

    Carbonylation is the covalent, non-reversible modification of the side chains of cysteine, histidine, and lysine residues by lipid peroxidation end products such as 4-hydroxy- and 4-oxononenal. In adipose tissue the effects of such modifications are associated with increased oxidative stress and metabolic dysregulation centered on mitochondrial energy metabolism. To address the role of protein carbonylation in the pathogenesis of mitochondrial dysfunction, quantitative proteomics was employed to identify specific targets of carbonylation in GSTA4-silenced or overexpressing 3T3-L1 adipocytes. GSTA4-silenced adipocytes displayed elevated carbonylation of several key mitochondrial proteins including the phosphate carrier protein, NADH dehydrogenase 1α subcomplexes 2 and 3, translocase of inner mitochondrial membrane 50, and valyl-tRNA synthetase. Elevated protein carbonylation is accompanied by diminished complex I activity, impaired respiration, increased superoxide production, and a reduction in membrane potential without changes in mitochondrial number, area, or density. Silencing of the phosphate carrier or NADH dehydrogenase 1α subcomplexes 2 or 3 in 3T3-L1 cells results in decreased basal and maximal respiration. These results suggest that protein carbonylation plays a major instigating role in cytokine-dependent mitochondrial dysfunction and may be linked to the development of insulin resistance in the adipocyte.

  2. A new probe of solvent accessibility of bound photosensitizers. 1. Ruthenium(II) and osmium(II) photosensitizers in sodium lauryl sulfate micelles

    International Nuclear Information System (INIS)

    Hauenstein, B.L. Jr.; Dressick, W.J.; Buell, S.L.; Demas, J.N.; DeGraff, B.A.

    1983-01-01

    A new method of measuring solvent accessibility of photosensitizers bound to organized media is presented. In particular, the solvent accessibility of a series of ruthenium(II) and osmium(II) photosensitizers bound to sodium lauryl sulfate micelles has been determined. The method takes advantage of the large solvent deuterium effect on the excited-state lifetimes of these complexes. The solvent accessibility of the bound complexes correlates with the hydrophobicity of the ligands. The potential application of this method to a variety of other systems is mentioned

  3. Photorefractive IR-spectrum composites prepared from polyimide and ruthenium(II) tetra-15-crown-5-phthalocyaninate with axially coordinated triethylenediamine molecules

    International Nuclear Information System (INIS)

    Vannikov, A.V.; Grishina, A.D.; Gorbunova, Yu.G.; Enakieva, Yu.Yu.; Krivenko, T.V.; Savel'ev, V.V.; Tsivadze, A.Yu.

    2006-01-01

    Photoelectric, non-linear optical, and photorefractive properties of aromatic polyimine doped with ruthenium(II) complex with tetra-15-crown-5-phthalocyanine and axially coordinated triethylenediamine molecules, (R 4 Pc)Ru(TED) 2 , where R 4 Pc 2- and TED denote 4,5,4',5',4'',5'',4''',5'''-tetrakis-(1,4,7,10,13- pentaoxatridecamethylene)phthalocyaninate ion and triethylenediamine molecule, respectively, were studied. It is established that supramolecular ensembles on the basis of the complex make an aromatic polyimide layer photoelectrically sensitive to 1064-nm Nd : YAG laser radiation, exhibit third-order susceptibility, and, consequently, impart photorefractive properties to the polymer layer at this wavelength [ru

  4. Ruthenium(II) complexes containing bidentate Schiff bases and ...

    Indian Academy of Sciences (India)

    Unknown

    triphenylphosphine or triphenylarsine. P VISWANATHAMURTHIa ... catalytic activities in the oxidation of benzyl alcohol to benzaldehyde. Keywords. Monobasic ... primarily because of the fascinating electron-transfer, photochemical and cata-.

  5. Reciprocal carbonyl-carbonyl interactions in small molecules and proteins.

    Science.gov (United States)

    Rahim, Abdur; Saha, Pinaki; Jha, Kunal Kumar; Sukumar, Nagamani; Sarma, Bani Kanta

    2017-07-19

    Carbonyl-carbonyl n→π* interactions where a lone pair (n) of the oxygen atom of a carbonyl group is delocalized over the π* orbital of a nearby carbonyl group have attracted a lot of attention in recent years due to their ability to affect the 3D structure of small molecules, polyesters, peptides, and proteins. In this paper, we report the discovery of a "reciprocal" carbonyl-carbonyl interaction with substantial back and forth n→π* and π→π* electron delocalization between neighboring carbonyl groups. We have carried out experimental studies, analyses of crystallographic databases and theoretical calculations to show the presence of this interaction in both small molecules and proteins. In proteins, these interactions are primarily found in polyproline II (PPII) helices. As PPII are the most abundant secondary structures in unfolded proteins, we propose that these local interactions may have implications in protein folding.Carbonyl-carbonyl π* non covalent interactions affect the structure and stability of small molecules and proteins. Here, the authors carry out experimental studies, analyses of crystallographic databases and theoretical calculations to describe an additional type of carbonyl-carbonyl interaction.

  6. Metagenomes of complex microbial consortia derived from different soils as sources for novel genes conferring formation of carbonyls from short-chain polyols on Escherichia coli.

    Science.gov (United States)

    Knietsch, Anja; Waschkowitz, Tanja; Bowien, Susanne; Henne, Anke; Daniel, Rolf

    2003-01-01

    Metagenomic DNA libraries from three different soil samples (meadow, sugar beet field, cropland) were constructed. The three unamplified libraries comprised approximately 1267000 independent clones and harbored approximately 4.05 Gbp of environmental DNA. Approximately 300000 recombinant Escherichia coli strains of each library per test substrate were screened for the production of carbonyls from short-chain (C2 to C4) polyols such as 1,2-ethanediol, 2,3-butanediol, and a mixture of glycerol and 1,2-propanediol on indicator agar. Twenty-four positive E. COLI clones were obtained during the initial screen. Fifteen of them contained recombinant plasmids, designated pAK201-215, which conferred a stable carbonyl-forming phenotype on E. coli Sequencing revealed that the inserts of pAK201-215 encoded 26 complete and 14 incomplete predicted protein-encoding genes. Most of these genes were similar to genes with unknown functions from other microorganisms or unrelated to any other known gene. The further analysis was focused on the 7 plasmids (pAK204, pAK206, pAK208, and pAK210-213) recovered from the positive clones, which exhibited an NAD(H)-dependent alcohol oxidoreductase activity with polyols or the correlating carbonyls as substrates in crude extracts. Three genes (ORF6, ORF24, and ORF25) conferring this activity were identified during subcloning of the inserts of pAK204, pAK211, and pAK212. The sequences of the three deduced gene products revealed no significant similarities to known alcohol oxidoreductases, but contained putative glycine-rich regions, which are characteristic for binding of nicotinamide cofactors. Copyright 2003 S. Karger AG, Basel

  7. Validation of protein carbonyl measurement

    DEFF Research Database (Denmark)

    Augustyniak, Edyta; Adam, Aisha; Wojdyla, Katarzyna

    2015-01-01

    Protein carbonyls are widely analysed as a measure of protein oxidation. Several different methods exist for their determination. A previous study had described orders of magnitude variance that existed when protein carbonyls were analysed in a single laboratory by ELISA using different commercial...... protein carbonyl analysis across Europe. ELISA and Western blotting techniques detected an increase in protein carbonyl formation between 0 and 5min of UV irradiation irrespective of method used. After irradiation for 15min, less oxidation was detected by half of the laboratories than after 5min...... irradiation. Three of the four ELISA carbonyl results fell within 95% confidence intervals. Likely errors in calculating absolute carbonyl values may be attributed to differences in standardisation. Out of up to 88 proteins identified as containing carbonyl groups after tryptic cleavage of irradiated...

  8. Linkage isomerism of carbonyl coordination complexes formed upon CO adsorption on the zeolite Li-ZSM-5: variable-temperature FTIR studies

    Science.gov (United States)

    Otero Areán, C.; Rodríguez Delgado, M.; Manoilova, O. V.; Turnes Palomino, G.; Tsyganenko, A. A.; Garrone, E.

    2002-08-01

    Carbon monoxide adsorbed at a low-temperature on the zeolite Li-ZSM-5 forms Li +⋯CO and Li +⋯(CO) 2 species characterized by C-O stretching bands at 2195 and 2187 cm-1, respectively. These C-bonded carbonyls are in a temperature-dependent equilibrium with Li +⋯OC and CO⋯Li +⋯CO species having O-bonded CO. By means of variable-temperature FTIR spectroscopy, the enthalpy change involved in the corresponding isomerization process was found to be ΔH°=7.8 kJ mol-1 for the monocarbonyl and ΔH°=5.1 kJ mol-1 for the dicarbonyl. Therefore, although C-bonded species were always found to show a higher cation-CO interaction energy than O-bonded species, the difference is smaller in the case of dicarbonyls.

  9. Design and synthesis of ruthenium(II) OCO pincer type NHC ...

    Indian Academy of Sciences (India)

    The tridentate nature of the tBu(OCO)2− ligand as well as some level of steric protection ... our previous results of ruthenium(II) o-hydroxyaryl sub- stituted bidentate NHC ...... (a) Ribelin T, Katz C E, English D G, Smith S,. Manukyan A K, Day ...

  10. Synthesis and characterization of bisoxazolines- and pybox-copper(II) complexes and their application in the coupling of α-carbonyls with functionalized amines

    KAUST Repository

    Jia, Weiguo; Li, Dandan; Dai, Yuanchen; Zhang, Hui; Yan, Liqin; Sheng, Enhong; Wei, Yun; Mu, Xiaolong; Huang, Kuo-Wei

    2014-01-01

    Binuclear complexes [{(DMOX)CuCl}2(μ-Cl)2] (1), mononuclear complexes [(DMOX)CuBr2] (2) (DMOX = 4,5-dihydro-2-(4,5- dihydro-4,4-dimethyloxazol-2-yl)-4,4-dimethyloxazole) and the pybox Cu(ii) complex [(Dm-Pybox)CuBr2] (3) (Dm-Pybox = 2,6-bis[4′,4

  11. Electrochemiluminescence and chemiluminescence of a carboxylic acid derivative of ruthenium(II) tris-(2,2'-bipyridine) chelate synthesized for labeling purposes

    International Nuclear Information System (INIS)

    Jiang Qinghong; Sun Shiguo; Hakansson, Markus; Langel, Kaarina; Ylinen, Tiina; Suomi, Johanna; Kulmala, Sakari

    2006-01-01

    Synthesis, purification and characterization of [4-ethoxycarbonyl-4'-carboxy-2,2'-bipyridine]bis(2,2'-bipyridine) ruthenium(II) hexafluorophosphate is described. This complex is shown to be electrochemiluminescent in aqueous solution during cathodic pulse polarization of thin insulating film-coated electrodes. Electrochemiluminescence (ECL) lifetime of the complex was observed to be ca. 40 μs at oxide-coated n-silicon electrodes; thus time-resolved detection is also possible. The ECL emission maximum of this carboxylate derivative is somewhat red-shifted when compared with an unmodified Ru(bpy) 3 2+ . Because the present complex can be easily covalently coupled with antibodies and oligonucleotides it is usable as an electrochemiluminescent label in various bioaffinity assays. The present chelates also produce strong chemiluminescence during dissolution of metallic magnesium in aqueous solution

  12. Reactions of the dirhenium(II) complexes Re2X4(dppm)2 (X = Cl, Br; dppm = Ph2PCH2PPh2) with isocyanides. 5. Mixed carbonyl-isocyanide and carbonyl-isocyanide-nitrile complexes of stoichiometry (Re2Cl3(dppm)2(CO)(CNR)(L))PF6 (R = t-Bu, xyl (Xylyl); L = t-BuNC, xylNC, MeCN, EtCN). Structural characterization of the cation (Cl2(CO)Re(μ-dppm)2ReCl (CN-t-Bu)2)+

    International Nuclear Information System (INIS)

    Fanwick, P.E.; Price, A.C.; Walton, R.A.

    1988-01-01

    Several dirhenium (II) species that contain mixed sets of carbonyl, isocyanide, and/or nitrile ligands have been prepared from the reactions between Re 2 Cl 4 (dppm) 2 (CO)(CNR) (dppm = Ph 2 PCHPPh 2 ; R = t-Bu, xyl (xylyl)), and the appropriate ligands in the presence of TlPF 6 . The crystal structures of these compounds are reported. The terminally-bound ligand noted in the complexes (Re 2 Cl 3 (dppm) 2 (CO)(CN-t-Bu) 2 )PF 6 and (Re 2 CL 3 (dppm) 2 (CO)(CN-t-Bu)(CNxyl))PF 6 indicates structures that have not been previously reported. Complexes in which there are mixed sets of carbonyl, isocyanide, and nitrile ligands, viz. (Re 2 Cl 3 (dppm) 2 (CO)(CNR)(CNR'))PF 6 are also reported. 20 refs., 1 fig., 5 tabs

  13. Selective Oxidative Carbonylation of Aniline to Diphenylurea with Ionic Liquids

    DEFF Research Database (Denmark)

    Zahrtmann, Nanette; Claver, Carmen; Godard, Cyril

    2018-01-01

    A catalytic system for the selective oxidative carbonylation of aniline to diphenylurea based on Pd complexes in combination with imidazolium ionic liquids is presented. Both oxidants, Pd complexes and ionic liquids affect the activity of the reaction while the choice of oxidant determines...

  14. Existence of both blue-shifting hydrogen bond and Lewis acid-base interaction in the complexes of carbonyls and thiocarbonyls with carbon dioxide.

    Science.gov (United States)

    Nguyen, Tien Trung; Nguyen, Phi Hung; Tran, Thanh Hue; Minh, Tho Nguyen

    2011-08-21

    In this study, 16 gas phase complexes of the pairs of XCHZ and CO(2) (X = F, Cl, Br; Z = O, S) have been identified. Interaction energies calculated at the CCSD(T)/aug-cc-pVTZ//MP2/aug-cc-pVTZ level including both BSSE and ZPE corrections range from -5.6 to -10.5 kJ mol(-1) for XCHOCO(2) and from -5.7 to -9.1 kJ mol(-1) for XCHS···CO(2). Substitution of one H atom by one halogen in formaldehyde and thioformaldehyde reduces the interaction energy of XCHZ···CO(2), while a CH(3) substitution increases the interaction energy of both CH(3)CHO···CO(2) and CH(3)CHS···CO(2). NBO and AIM analyses also point out that the strength of Lewis acid-base interactions decreases going from >C1=S3···C6 to >C1=O3C6 and to >C1-X4···C6. This result suggests the higher capacity of solubility of thiocarbonyl compounds in scCO(2), providing an enormous potential application for designing CO(2)-philic materials based on the >C=S functional group in competition with >C=O. The Lewis acid-base interaction of the types >C=S···C, >C-Cl···C and >C-Br···C is demonstrated for the first time. The contribution of the hydrogen bonding interaction to the total interaction energy is larger for XCHS···CO(2) than for XCHO···CO(2). Upon complexation, a contraction of the C1-H2 bond length and a blue shift of its stretching frequency have been observed, as compared to the isolated monomer, indicating the existence of a blue-shifting hydrogen bond in all complexes examined. Calculated results also lend further support for the viewpoint that when acting as proton donor, a C-H bond having a weaker polarization will induce a stronger distance contraction and frequency blue shift upon complexation, and vice versa.

  15. Organometallic Half-Sandwich Iridium Anticancer Complexes

    Czech Academy of Sciences Publication Activity Database

    Liu, Z.; Habtemariam, A.; Pizarro, A.M.; Fletcher, S.A.; Kisová, Anna; Vrána, Oldřich; Salassa, L.; Bruijnincx, P.C.A.; Clarkson, G.J.; Brabec, Viktor; Sadler, P. J.

    2011-01-01

    Roč. 54, č. 8 (2011), 3011-3026 ISSN 0022-2623 R&D Projects: GA ČR(CZ) GPP303/11/P047; GA ČR(CZ) GAP301/10/0598 Keywords : RUTHENIUM(II) ARENE COMPLEXES * CANCER-CELL CYTOTOXICITY * DNA-BINDING PROPERTIES Subject RIV: BO - Biophysics Impact factor: 5.248, year: 2011

  16. Structural Properties and UV-Visible Absorption Spectroscopy of Retinal-pyridyl-CN Re(I) Carbonyl Bipyridine Complex: A Theoretical Study.

    Science.gov (United States)

    Eng, Julien; Daniel, Chantal

    2015-10-29

    The structural, electronic, and optical properties of the all-trans and five cis conformers of [Re(CO)3(bpy)(ret-pyr-CN)](+) (bpy = 2,2'-bipyridine; ret-pyr-CN = pyridyl-CN-3,7-dimethyl-9-(2,6,6-trimethylcyclohex-2-n)-none-(2,4,6,8-tetraen) were studied in solvent by means of density functional theory (DFT) and time-dependent DFT. The isolated retinal-like chromophore ret-pyr-CN was investigated as well for comparison. By coordination to the complex the two lowest intraligand (IL) states localized on the retinal group are slightly red-shifted from 627 to 690 nm and from 415 to 450 nm, respectively. Several isomerization pathways are open upon irradiation of the Re(I) complex by visible light (400-450 nm), especially to two cis conformers corresponding to the isomerization of the two double bonds of the retinal-like ligand close to the pyridyl group linked to the Re(I) fragment. The metal-to-ligand charge transfer states localized either on the retinal group or on the bpy ligand should play a minor role in the isomerization process itself but could improve its efficiency via ultra-fast intersystem crossing.

  17. Comparative study of the anchorage and the catalytic properties of nanoporous TiO2 films modified with ruthenium (II) and rhenium (I) carbonyl complexes

    Science.gov (United States)

    Oyarzún, Diego P.; Chardon-Noblat, Sylvie; Linarez Pérez, Omar E.; López Teijelo, Manuel; Zúñiga, César; Zarate, Ximena; Shott, Eduardo; Carreño, Alexander; Arratia-Perez, Ramiro

    2018-02-01

    In this article we study the anchoring of cis-[Ru(bpyC4pyr)(CO)2(CH3CN)2]2+, cis-[Ru(bpy)2(CO)2]2+ and cis-[Ru(bpyac)(CO)2Cl2], onto nanoporous TiO2 employing electropolymerization, electrostatic interaction and chemical bonding. Also, the [Re(bpyac)(CO)3Cl] rhenium(I) complex for chemical anchorage was analyzed. The characterization of TiO2/Ru(II) and TiO2/Re(I) nanocomposite films was performed by field emission scanning electron microscopy (FESEM), electron dispersive X-ray spectroscopy (EDS) and Raman spectroscopy. In addition, for the more stable nanocomposites obtained, the catalytic properties (solar energy conversion and CO2 reduction) were evaluated. The efficiency improvement in redox process derived from the (photo)electrochemical evidence indicates that modified nanoporous TiO2 structures enhance the rate of charge transfer reactions.

  18. Reactions of ruthenium and osmium cluster carbonyls with heteroatom-substituted and functionalized alkynes

    International Nuclear Information System (INIS)

    Koridze, A.A.

    2000-01-01

    The results of studies of the reactions of ruthenium and osmium cluster carbonyls with metal (M = Re, Mn, Fe) alkynes, silylalkynes, propargyl alcohols and their derivatives, diynes, enynes, and ferrocenylacetylene are summarized. Intramolecular rearrangements in the cluster complexes including migrations of carbonyl, hydride, and hydrocarbon ligands and the metal core reorganization are considered [ru

  19. Characterization of a Novel 99mTc-Carbonyl Complex as a Functional Probe of MDR1 P-Glycoprotein Transport Activity

    Directory of Open Access Journals (Sweden)

    Mary Dyszlewski

    2002-01-01

    Full Text Available Multidrug resistance (MDR mediated by overexpression of MDR1 P-glycoprotein (Pgp is one of the best characterized barriers to chemotherapy in cancer patients. Furthermore, the protective function of Pgp-mediated efflux of xenobiotics in various organs has a profound effect on the bioavailability of drugs in general. Thus, there is an expanding requirement to noninvasively interrogate Pgp transport activity in vivo. We herein report the Pgp recognition properties of a novel 99mTc(I-tricarbonyl complex, [99mTc(CO3(MIBI3] + (Tc-CO-MIBI. Tc-CO-MIBI showed 60-fold higher accumulation in drug-sensitive KB 3–1 cells compared to colchicine-selected drug-resistant KB 8-5 cells. In KB 8-5 cells, tracer enhancement was observed with the potent MDR modulator LY335979 (EC50 = 62 nM. Similar behavior was observed using drug-sensitive MCF-7 breast adenocarcinoma cells and MCF-7/MDR1 stable transfectants, confirming that Tc-CO-MIBI is specifically excluded by overexpression of MDR1 Pgp. By comparison, net accumulation in control H69 lung tumor cells was 9-fold higher than in MDR-associated protein (MRP1-expressing H69AR cells, indicating only modest transport by MRP1. Biodistribution analysis following tail vein injection of Tc-CO-MIBI showed delayed liver clearance as well as enhanced brain uptake and retention in mdr1a/1b(−/− gene deleted mice versus wild-type mice, directly demonstrating that Tc-CO-MIBI is a functional probe of Pgp transport activity in vivo.

  20. Radical carbonylations using a continuous microflow system

    Directory of Open Access Journals (Sweden)

    Takahide Fukuyama

    2009-07-01

    Full Text Available Radical-based carbonylation reactions of alkyl halides were conducted in a microflow reactor under pressurized carbon monoxide gas. Good to excellent yields of carbonylated products were obtained via radical formylation, carbonylative cyclization and three-component coupling reactions, using tributyltin hydride or TTMSS as a radical mediator.

  1. (II) complexes containing isocyanide and labile nitrile ligands

    African Journals Online (AJOL)

    A new ruthenium(II) complex containing both acetonitrile and propionitrile moieties as coordinating ligands has been prepared. The treatment of the polymer [{RuCl2(COD)}x], (COD = cycloocta-1,5-diene) (1) with a mixture of acetonitrile and propionitrile under reflux produced a new precursor ...

  2. Beyond alkyl transfer: Synthesis of main group metal (Mg, Ca, Zn) silyl and tris(oxazolinyl)borato complexes and their stoichiometric and catalytic reactions with borane Lewis acids and carbonyls

    Energy Technology Data Exchange (ETDEWEB)

    Lampland, Nicole Lynn [Iowa State Univ., Ames, IA (United States)

    2015-05-09

    Recently, the fundamental knowledge of main group metal chemistry has grown. This progress is crucial for the further development of main group metal compounds in silicon chemistry and catalysis and for advancing their applications as green alternatives to many rare earth and transition metal compounds. This thesis focuses on reactivity beyond the welldocumented alkyl-transfer applications for main group metals, and it highlights examples of reactions with Lewis acids and the reduction of carbonyls.

  3. Transition metal catalyzed carbonylation reactions carbonylative activation of C-X bonds

    CERN Document Server

    Beller, Matthias

    2014-01-01

    This book provides students and researchers in organic synthesis with a detailed discussion of carbonylation from the basics through to applications. It discusses the past, present and future of carbonylation reactions.

  4. Organoruthenium Complexes with CN Ligands are Highly Potent Cytotoxic Agents that Act by a New Mechanism of Action

    Czech Academy of Sciences Publication Activity Database

    Novohradský, Vojtěch; Yellol, J.; Stuchlíková, O.; Santana, M.D.; Kostrhunová, Hana; Yellol, G.; Kašpárková, Jana; Bautista, D.; Ruiz, J.; Brabec, Viktor

    2017-01-01

    Roč. 23, č. 61 (2017), s. 15294-15299 ISSN 0947-6539 R&D Projects: GA ČR(CZ) GA17-05302S Institutional support: RVO:68081707 Keywords : chemotherapeutic-agents * ruthenium(ii) complexes * iridium(iii) complexes Subject RIV: CE - Biochemistry OBOR OECD: Biochemistry and molecular biology Impact factor: 5.317, year: 2016

  5. Ruthenium and osmium carbonyl nitrosyl complexes: Matrix infrared spectra and density functional calculations for M(CO){sub 2}(NO){sub 2} and M(CO)(NO) (M = Ru, Os)

    Energy Technology Data Exchange (ETDEWEB)

    Song, Zhenjun [Department of Chemistry, Tongji University, Shanghai 200092 (China); Wang, Xuefeng, E-mail: xfwang@tongji.edu.cn [Department of Chemistry, Tongji University, Shanghai 200092 (China); Key Laboratory of Yangtze River Water Environment, Ministry of Education, Tongji University (China)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer Laser-ablated ruthenium or osmium atom reactions with CO and NO mixtures in solid argon. Black-Right-Pointing-Pointer Metal carbonyl nitrosyls including M(CO)(NO) and 18-electron configuration M(CO){sub 2}(NO){sub 2} molecules (M = Ru, Os). Black-Right-Pointing-Pointer The observed absorption bands of reaction products are identified by isotopic substitution and DFT calculations. Black-Right-Pointing-Pointer The bonding and reaction mechanism are discussed in detail. -- Abstract: Laser-ablated ruthenium or osmium atom reactions with CO and NO mixtures in solid argon produce unsaturated metal carbonyl nitrosyls including M(CO)(NO) and 18-electron configuration M(CO){sub 2}(NO){sub 2} molecules (M = Ru, Os). The observed absorption bands of reaction products are identified by isotopic substitution, isotopic ratios and isotopic distributions ({sup 13}CO, {sup 15}NO, and mixtures). DFT (B3LYP and BP86) vibrational fundamental calculations reproduce observed frequencies and isotopic shifts very well. The bonding and reaction mechanism are discussed.

  6. Influence of halogen substitution in the ligand sphere on the antitumor and antibacterial activity of half-sandwich ruthenium(II) complexes [RuX(η{sup 6}-arene)(C{sub 5}H{sub 4}N-2-cH=N-Ar)]{sup +}

    Energy Technology Data Exchange (ETDEWEB)

    Gichumbi, Joel M.; Omondi, Bernard; Friedrich, Holger B. [School of Chemistry, University of KwaZulu-Natal, Durban (South Africa); Lazarus, Geraldine; Singh, Moganavelli; Shaikh, Nazia; Chenia, Hafizah Y. [School of Life Sciences, University of KwaZulu-Natal, Durban (South Africa)

    2017-06-01

    New complexes [(η{sup 6}-p-cymene)Ru(C{sub 5}H{sub 4}N-2-CH=N-Ar)X]PF{sub 6} [X = Br (1), I (2); Ar = 4-fluorophenyl (a), 4-chlorophenyl (b), 4-bromophenyl (c), 4-iodophenyl (d), 2,5-dichlorophenyl (e)] were prepared, as well as 3a-3e (X = Cl) and the new complexes [(η{sup 6}-arene)RuCl(N-N)]PF{sub 6} [arene = C{sub 6}H{sub 5}OCH{sub 2}CH{sub 2}OH, N-N = 2,2{sup '}-bipyridine (4), 2,6-(dimethylphenyl)-pyridin-2-yl-methylene amine (5), 2,6-(diisopropylphenyl)-pyridin-2-yl-methylene amine (6); arene = p-cymene, N-N = 4-(aminophenyl)-pyridin-2-yl-methylene amine (7)]. X-ray diffraction studies were performed for 1a, 1b, 1c, 1d, 2b, 5, and 7. Cytotoxicities of 1a-1d and 2 were established versus human cancer cells epithelial colorectal adenocarcinoma (Caco-2) (IC{sub 50}: 35.8-631.0 μM), breast adenocarcinoma (MCF7) (IC{sub 50}: 36.3-128.8.0 μM), and hepatocellular carcinoma (HepG2) (IC{sub 50}: 60.6-439.8 μM), 3a-3e were tested against HepG2 and Caco-2, and 4-7 were tested against Caco-2. 1-7 were tested against non-cancerous human epithelial kidney cells. 1 and 2 were more selective towards tumor cells than the anticancer drug 5-fluorouracil (5-FU), but 3a-3e (X = Cl) were not selective. 1 and 2 had good activity against MCF7, some with lower IC{sub 50} than 5-FU. Complexes with X = Br or I had moderate activity against Caco-2 and HepG2, but those with Cl were inactive. Antibacterial activities of 1a, 2b, 3a, and 7 were tested against antibacterial susceptible and resistant Gram-negative and -positive bacteria. 1a, 2b, and 3a showed activity against methicillin-resistant S. aureus (MIC = 31-2000 μg.mL{sup -1}). (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Macromolecules containing bipyridine and terpyridine metal complexes: towards metallo-supramolecular polymers

    NARCIS (Netherlands)

    Schubert, U.S.; Eschbaumer, C.

    2002-01-01

    The ability of a broad range of N-heterocycles to act as very effective and stable complexation agents for several transition metal ions, such as cobalt(II), copper(II), nickel(II), and ruthenium(II), has long been known in analytical chemistry. This behavior was later utilized in supramolecular

  8. New superhindered polydentate polyphosphine ligands P(CH2CH2P(t)Bu2)3, PhP(CH2CH2P(t)Bu2)2, P(CH2CH2CH2P(t)Bu2)3, and their ruthenium(II) chloride complexes.

    Science.gov (United States)

    Gilbert-Wilson, Ryan; Field, Leslie D; Bhadbhade, Mohan M

    2012-03-05

    The synthesis and characterization of the extremely hindered phosphine ligands, P(CH(2)CH(2)P(t)Bu(2))(3) (P(2)P(3)(tBu), 1), PhP(CH(2)CH(2)P(t)Bu(2))(2) (PhP(2)P(2)(tBu), 2), and P(CH(2)CH(2)CH(2)P(t)Bu(2))(3) (P(3)P(3)(tBu), 3) are reported, along with the synthesis and characterization of ruthenium chloro complexes RuCl(2)(P(2)P(3)(tBu)) (4), RuCl(2)(PhP(2)P(2)(tBu)) (5), and RuCl(2)(P(3)P(3)(tBu)) (6). The bulky P(2)P(3)(tBu) (1) and P(3)P(3)(tBu) (3) ligands are the most sterically encumbered PP(3)-type ligands so far synthesized, and in all cases, only three phosphorus donors are able to bind to the metal center. Complexes RuCl(2)(PhP(2)P(2)(tBu)) (5) and RuCl(2)(P(3)P(3)(tBu)) (6) were characterized by crystallography. Low temperature solution and solid state (31)P{(1)H} NMR were used to demonstrate that the structure of RuCl(2)(P(2)P(3)(tBu)) (4) is probably analogous to that of RuCl(2)(PhP(2)P(2)(tBu)) (5) which had been structurally characterized.

  9. Selective transformation of carbonyl ligands to organic molecules

    Energy Technology Data Exchange (ETDEWEB)

    Cutler, A.R.

    1992-05-12

    Studies on the carbonylation of ({eta}{sup 5}-indenyl)(L)(CO)Ru-R complexes (L = CO, PPh{sub 3}; R = CH{sub 2}OMe, CH{sub 3}) have been completed. Particularly noteworthy is that the methoxymethyl complexes readily transform to their acyl derivatives under mild conditions that leave their iron congeners inert towards CO. Surprisingly, even ({eta}{sup 5}-indenyl)(PPh{sub 3}){sub 2}Ru-CH{sub 3} carbonylates and gives ({eta}{sup 5}-indenyl)(PPh{sub 3})(CO)Ru-C(O)CH{sub 3}. Mechanistic studies on the non catalyzed'' hydrosilation of the manganese acyls (CO){sub 5}Mn-C(O)CH{sub 2}R (R = H, OCH{sub 3}, CH{sub 3}) with Et{sub 3}SiH and of cobalt acetyls (CO){sub 3}(PR{sub 3})CoC(O)CH{sub 3} with several monohydrosilanes have been completed. The cobalt acetyls cleanly give ethoxysilanes (not acetaldehyde), and the manganese acyls provide {alpha}-siloxyvinyl complexes Z-(CO){sub 5}Mn-C(OSiEt{sub 3})=CHR (R = H, CH{sub 3}, OCH{sub 3}). Carbonylation and protolytic cleavage of the latter generate pyruvoyl complexes (CO){sub 5}Mn-COCOR (R = CH{sub 3}, CH{sub 2}CH{sub 3}), formally the products of net double carbonylation'' sequences. Studies in progress are concerned with how manganese complexes as diverse as (CO){sub 5}Mn-Y (Y = C(O)R, R, BR - but not SiMe{sub 3} or Mn(CO){sub 5}) and ({eta}{sup 3}-C{sub 3}H{sub 5})Mn(CO){sub 2}L (but not CpMn(CO){sub 3} or CpMn(CO){sub 2}({eta}{sup 2}HSiR{sub 3})) function as efficient hydrosilation catalysts towards Cp(CO){sub 2}FeC(O)CH{sub 3}, for example. These reactions cleanly afford fully characterized {alpha}-siloxyethyl complexes Fp-CH(OSiR{sub 3})CH{sub 3} under conditions where typically Rh(1) hydrosilation catalysts are inactive. Several of these manganese complexes also catalytically hydrosilate organic esters, including lactones, to their ethers R-CH{sub 2}OR; these novel ester reductions occur quantitatively at room temperature and appear to be general in scope.

  10. Elution behavior of N-heterocyclic derivatives of mixed ruthenium(II)-sulfoxide complexes in reversed-phase high-performance liquid chromatography

    International Nuclear Information System (INIS)

    Toma, H.E.; Silva, D.O.

    1991-01-01

    The elution behaviour of a series of dichlorobis-(dimethylsulfoxide)bis(N-heterocyclic) ruthenium(II) complexes has been investigated using reversed-phase HPLC. Similar trends as those displayed by the free N-heterocyclic bases have been observed for the complexes, essentially reflecting the hydrophobic properties of the aromatic ligands. (orig.)

  11. Reinvestigating 2,5-di(pyridin-2-yl)pyrazine ruthenium complexes : Selective deuteration and Raman spectroscopy as tools to probe ground and excited-state electronic structure in homo- and heterobimetallic complexes

    NARCIS (Netherlands)

    Schulz, M.; Hirschmann, J.; Draksharapu, A.; Singh Bindra, G.; Soman, S.; Paul, A.; Groarke, R.; T. Pryce, M.; Rau, S.; R. Browne, W.; Vos, J.

    2011-01-01

    The mono- (1) and dinuclear (2) ruthenium(II) bis(2,2'-bipyridine) complexes of 2,5-di(pyridin-2-yl)pyrazine (2,5-dpp), for which the UV/Vis absorption and emission as well as electrochemical properties have been described earlier, are reinvestigated here by resonance, surface enhanced and transient

  12. The thermodynamic effects of ligand structure on the molecular recognition of mononuclear ruthenium polypyridyl complexes with B-DNA

    Science.gov (United States)

    The ruthenium(II) polypyridyl complexes (RPCs), [(phen)2Ru(tatpp)]Cl2 (3Cl2) and [(phen)2Ru (tatpp)Ru(phen)2]Cl4 (4Cl4), containing the large planar and redox-active tetraazatetrapyrido- pentacene (tatpp) ligand, cleave DNA in the presence of reducing agents in cell-free assays and show significant...

  13. Substituent Effects and Bonding Characteristics in o- Benzoquinonediiminebis(bipyrdine) Ruthenium(II) Complexes

    Science.gov (United States)

    1992-10-23

    C.; Dei, A.; Gatteschi , D.; Pardi, L Inorg. Chem. 1989, 2L 1476; (b) Benel, C.; Dei, A.; Gatteschi , D.; Ckdel, H. U.; Pardi, L Inorg. Ckem. 1989, 28...3091; (c) Benelli, C.; Dei, A.; Gatteschi , D.; Pardi, L Inorg.Chem. 1990,2& 3409. 16. Bruni, S.; Cariati, F.; Dei, A.; Gatteschi , D. Inog Cbim. Ata...1991, 186 157. 17. Dei, A.; Gatteschi , D.; Pardi, L; Barra, A. L; Brunel, L C. Chem, Py. Lett.. 1990, 175. 589; Dei, A.; Pardi, L Inorg, Chim.Acta

  14. Transfer Hydro-dehalogenation of Organic Halides Catalyzed by Ruthenium(II) Complex.

    Science.gov (United States)

    You, Tingjie; Wang, Zhenrong; Chen, Jiajia; Xia, Yuanzhi

    2017-02-03

    A simple and efficient Ru(II)-catalyzed transfer hydro-dehalogenation of organic halides using 2-propanol solvent as the hydride source was reported. This methodology is applicable for hydro-dehalogenation of a variety of aromatic halides and α-haloesters and amides without additional ligand, and quantitative yields were achieved in many cases. The potential synthetic application of this method was demonstrated by efficient gram-scale transformation with catalyst loading as low as 0.5 mol %.

  15. DNA interactions of monofuntional organometallic ruthenium(II) antitumor complexes in cell-free media

    Czech Academy of Sciences Publication Activity Database

    Nováková, Olga; Chen, H.; Vrána, Oldřich; Rodger, A.; Sadler, P. J.; Brabec, Viktor

    2003-01-01

    Roč. 42, č. 39 (2003), s. 11544-11554 ISSN 0006-2960 R&D Projects: GA ČR GA305/02/1552; GA ČR GA305/01/0418; GA AV ČR IAA5004101; GA MŠk OC D20.002; GA MŠk OC D20.005 Institutional research plan: CEZ:AV0Z5004920 Keywords : double-helical DNA * interstrand cross-links * biophysical analysis Subject RIV: BO - Biophysics Impact factor: 3.922, year: 2003

  16. New mixed ligand complexes of ruthenium(II) that incorporate a ...

    Indian Academy of Sciences (India)

    Unknown

    infrared, UV-Vis, steady-state emission and 1H NMR spectroscopic methods. Results ... Deionised, triply distilled water was used for preparing various buffers. .... 259 nm in CH3CN containing a drop of HCl (acid was added to ensure complete.

  17. The contrasting chemistry and cancer cell cytotoxicity of bipyridine and bipyridinediol ruthenium(II) arene complexes

    Czech Academy of Sciences Publication Activity Database

    Bugarcic, T.; Habtemariam, A.; Štěpánková, Jana; Heringová, Pavla; Kašpárková, Jana; Deeth, R.J.; Johnstone, R.D.L.; Prescimone, A.; Parkin, A.; Parsons, S.; Brabec, Viktor; Sadler, P.J.

    2008-01-01

    Roč. 47, č. 24 (2008), s. 11470-11486 ISSN 0020-1669 R&D Projects: GA MŠk(CZ) LC06030; GA MŠk(CZ) ME08017; GA MŠk(CZ) OC08003; GA AV ČR(CZ) 1QS500040581; GA AV ČR(CZ) KAN200200651; GA AV ČR(CZ) IAA400040803; GA MZd(CZ) NR8562 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : DNA * ruthenium * cancer Subject RIV: BO - Biophysics Impact factor: 4.147, year: 2008

  18. Bifunctional amine-tethered ruthenium(II) arene complexes form monofunctional adducts on DNA

    Czech Academy of Sciences Publication Activity Database

    Melchart, M.; Habtemariam, A.; Nováková, Olga; Moggach, S.A.; Fabbiani, F.P.A.; Parsons, S.; Brabec, Viktor; Sadler, P.J.

    2007-01-01

    Roč. 46, č. 21 (2007), s. 8950-8962 ISSN 0020-1669 R&D Projects: GA ČR(CZ) GA305/05/2030; GA ČR(CZ) GA203/06/1239; GA AV ČR(CZ) 1QS500040581; GA AV ČR(CZ) KAN200200651 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : DNA * ruthenium * cancer Subject RIV: BO - Biophysics Impact factor: 4.123, year: 2007

  19. Glucosinolates and isothiocyanates from broccoliseed extractsuppressproteinglycationand carbonylation

    Directory of Open Access Journals (Sweden)

    Marina Hirano,

    2018-01-01

    Full Text Available Background: Glucosinolates from brassica plants are hydrolyzed by internal or salivary myrosinase to produce isothiocyanates. Glucoraphanin, a major glucosinolate in broccoli, is hydrolyzed to sulforaphane (SFN, which exhibits antitumor and detoxification activities. Regarding the influence of broccoli and its constituents on the skin, a few studies have reported anti-inflammatory and antioxidant effects. Recently, advanced glycation end products (AGEs and carbonyl proteins have been reported to accelerate skin aging. Objective: We evaluated the effects of broccoli seed extract (BSE and glucosinolates on protein glycation and carbonylation in vitro. Methods: To evaluate the effects of BSE and its constituents, protein glycation and carbonylation were induced by mixing fructose with bovine serum albumin (BSA and then measuring production of AGEs, fructosamine, and carbonyl proteins (CP. Production of CP after mixing fatty acids with BSA was also assessed. Furthermore, the effect of BSE and its constituents on CP production by human fibroblasts (TIG103 was examined. Results: BSE suppressed the production of AGEs, fructosamine, and CP after mixing fructose and BSA. BSE also suppressed production of CP when oxidized linoleic acid was mixed with BSA. Isothiocyanates, including SFN and iberin, suppressed fructose-based CP production, but SFN had no effect on CP production stimulated by oxidized linoleic acid. In contrast, glucosinolates from BSE did not suppress fructose-based CP production, but suppressed CP production due to oxidized linoleic acid. Among the glucosinolates in BSE, glucoberteroin showed the strongest suppression of CP production. CP production in fibroblasts was also suppressed by glucosinolates, including glucoiberin and glucoberteroin. Conclusions: BSE demonstrated anti-glycation and anti-carbonylation effects on protein reactions with fructose and oxidized fatty acids. Isothiocyanates suppressed protein carbonylation induced by

  20. Spatiotemporal distribution of carbonyl compounds in China

    International Nuclear Information System (INIS)

    Ho, K.F.; Ho, Steven Sai Hang; Huang, R.-J.; Dai, W.T.; Cao, J.J.; Tian, Linwei; Deng, W.J.

    2015-01-01

    A sampling campaign was carried out at nine Chinese cities in 2010/2011. Fifteen monocarbonyls (C#= 1–9) were quantified. Temperature is the rate-determining factor of the summertime carbonyl levels. The carbonyl emissions in winter are mainly driven by the primary anthropogenic sources like automobile. A molar ratio of propionaldehyde to nonaldehyde is a barometer of the impact of atmospheric vegetation emission which suggesting that strong vegetation emissions exist in summer and high propionaldehyde abundance is caused by fossil fuel combustion in winter. Potential health risk assessment of formaldehyde and acetaldehyde was conducted and the highest cumulative risks were observed at Chengdu in summer and Wuhan in winter. Because of the strong photochemical reaction and large amount of anthropogenic emissions, high concentrations of carbonyl compounds were observed in Chengdu. The use of ethanol-blended gasoline in Wuhan is the key reason of acetaldehyde emission and action should be taken to avoid potential health risks. - Highlights: • A national wide survey of ambient carbonyl compounds were conducted in China. • Using ethanol-blended gasoline can lead to higher cancer risks. • High concentrations of HMW carbonyls (C6, C7, C8 and C9) were observed in all cities. • HMW carbonyls (C6–C9) species show a very consistent seasonal variation. • C 3 /C 9 acts as an indicator for the impact of vegetation emission in the atmosphere. - Capsule abstract: Strong vegetation emission occurs in summer atmosphere and high acetaldehyde emission due to ethanol-blended gasoline consumption in 9 Chinese cities is discouraged

  1. Excited-state dynamics of a ruthenium(II) catalyst studied by transient photofragmentation in gas phase and transient absorption in solution

    Energy Technology Data Exchange (ETDEWEB)

    Imanbaew, D.; Nosenko, Y. [Fachbereich Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 52–54, 67663 Kaiserslautern (Germany); Forschungszentrum OPTIMAS, Erwin-Schrödinger-Str. 46, 67663 Kaiserslautern (Germany); Kerner, C. [Fachbereich Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 52–54, 67663 Kaiserslautern (Germany); Chevalier, K.; Rupp, F. [Fachbereich Physik, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 46, 67663 Kaiserslautern (Germany); Riehn, C., E-mail: riehn@chemie.uni-kl.de [Fachbereich Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 52–54, 67663 Kaiserslautern (Germany); Forschungszentrum OPTIMAS, Erwin-Schrödinger-Str. 46, 67663 Kaiserslautern (Germany); Thiel, W.R. [Fachbereich Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 52–54, 67663 Kaiserslautern (Germany); Diller, R. [Fachbereich Physik, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 46, 67663 Kaiserslautern (Germany)

    2014-10-17

    Graphical abstract: - Highlights: • Ultrafast dynamics of new Ru(II) catalysts investigated in gas phase and solution. • Catalyst activation (HCl loss) achieved in ion trap by UV photoexcitation. • Electronic relaxation proceeds by IVR and IC followed by ground state dissociation. • No triplet formation in contrast to other Ru-polypyridine complexes. • Solvent prohibits catalyst activation in solution by fast vibrational cooling. - Abstract: We report studies on the excited state dynamics of new ruthenium(II) complexes [(η{sup 6}-cymene)RuCl(apypm)]PF{sub 6} (apypm=2-NR{sub 2}-4-(pyridine-2-yl)-pyrimidine, R=CH{sub 3} (1)/H (2)) which, in their active form [1{sup +}-HCl] and [2{sup +}-HCl], catalyze the transfer hydrogenation of arylalkyl ketones in the absence of a base. The investigations encompass femtosecond pump–probe transient mass spectrometry under isolated conditions and transient absorption spectroscopy in acetonitrile solution, both on the cations [(η{sup 6}-cymene)RuCl(apypm)]{sup +} (1{sup +}, 2{sup +}). Gas phase studies on mass selected ions were performed in an ESI ion trap mass spectrometer by transient photofragmentation, unambiguously proving the formation of the activated catalyst species [1{sup +}-HCl] or [2{sup +}-HCl] after photoexcitation being the only fragmentation channel. The primary excited state dynamics in the gas phase could be fitted to a biexponential decay, yielding time constants of <100 fs and 1–3 ps. Transient absorption spectroscopy performed in acetonitrile solution using femtosecond UV/Vis and IR probe laser pulses revealed additional deactivation processes on longer time scales (∼7–12 ps). However, the formation of the active catalyst species after photoexcitation could not be observed in solution. The results from both studies are compared to former CID investigations and DFT calculations concerning the activation mechanism.

  2. Convenient Reduction of Carbonyl Compounds to their ...

    African Journals Online (AJOL)

    NICO

    Alcohols and their derivatives occupy an important position in organic synthesis. ... review also reveals that the reduction of carbonyl compounds ..... 1 H.B. Ji and Y.B. She, Green Oxidation and Reduction, China Petrochemi- cal Press, Beijing ...

  3. Protein Carbonylation in Patients with Myelodysplastic Syndromes

    Czech Academy of Sciences Publication Activity Database

    Hlaváčková, A.; Štikarová, J.; Kotlín, R.; Chrastinová, L.; Šácha, Pavel; Májek, P.; Čermák, J.; Suttnar, J.; Dyr, J. E.

    2015-01-01

    Roč. 126, č. 23 (2015), s. 5232 ISSN 0006-4971. [Annual Meeting and Exposition of the American Society of Hematology /55./. 07.12.2013-10.12.2013, New Orleans] Institutional support: RVO:61388963 Keywords : protein carbonylation * myelodysplastic syndromes Subject RIV: CE - Biochemistry

  4. Synthesis, characterization and biological studies of 2-(4-nitrophenylamino-carbonyl)benzoic acid and its complexes with Cr(III), Co(II), Ni(II), Cu(II) and Zn(II)

    International Nuclear Information System (INIS)

    Imran, M; Nazir, S.; Latif, S.; Mahmood, Z.

    2010-01-01

    Cr(III), Co(II), Ni(II), Cu(II) and Zn(II) complexes of 2-(4-Nitrophenyl aminocarbonyl)benzoic acid were synthesized and characterized on the basis of physical, analytical and spectroscopic data. The ligands, as well as its metal complexes were checked for their in-vitro antimicrobial activity against three bacterial strains, Mycobacterium smegmatis, Escherichia coli, Pseudomonas aeuroginosa, and three fungal strains, Nigrospora oryzae, Aspergillus niger and Candida albicans. Disc diffusion method and Tube diffusion test were used for antibacterial and antifungal activities, respectively. The synthesized complexes only show significant antifungal activity but inactive for antibacterial, however, in general, the metal complexes were found to be more active against antimicrobial activities as compared to their un complexed ligand. (author)

  5. Millimeter wave spectra of carbonyl cyanide ⋆

    Science.gov (United States)

    Bteich, S.B.; Tercero, B.; Cernicharo, J.; Motiyenko, R.A.; Margulès, L.; Guillemin, J.-C.

    2016-01-01

    Context More than 30 cyanide derivatives of simple organic molecules have been detected in the interstellar medium, but only one dicarbonitrile has been found and that very recently. There is still a lack of high-resolution spectroscopic data particularly for dinitriles derivatives. The carbonyl cyanide molecule is a new and interesting candidate for astrophysical detection. It could be formed by the reaction of CO and CN radicals, or by substitution of the hydrogen atom by a cyano group in cyanoformaldehyde, HC(=O)CN, that has already been detected in the interstellar medium. Aims The available data on the rotational spectrum of carbonyl cyanide is limited in terms of quantum number values and frequency range, and does not allow accurate extrapolation of the spectrum into the millimeter-wave range. To provide a firm basis for astrophysical detection of carbonyl cyanide we studied its millimeter-wave spectrum. Methods The rotational spectrum of carbonyl cyanide was measured in the frequency range 152 - 308 GHz and analyzed using Watson’s A- and S-reduction Hamiltonians. Results The ground and first excited state of v5 vibrational mode were assigned and analyzed. More than 1100 distinct frequency lines of the ground state were fitted to produce an accurate set of rotational and centrifugal distortion constants up to the eighth order. The frequency predictions based on these constants should be accurate enough for astrophysical searches in the frequency range up to 500 GHz and for transition involving energy levels with J ≤ 100 and Ka ≤ 42. Based on the results we searched for interstellar carbonyl cyanide in available observational data without success. Thus, we derived upper limits to its column density in different sources. PMID:27738349

  6. Method for conversion of .beta.-hydroxy carbonyl compounds

    Science.gov (United States)

    Lilga, Michael A.; White, James F.; Holladay, Johnathan E.; Zacher, Alan H.; Muzatko, Danielle S.; Orth, Rick J.

    2010-03-30

    A process is disclosed for conversion of salts of .beta.-hydroxy carbonyl compounds forming useful conversion products including, e.g., .alpha.,.beta.-unsaturated carbonyl compounds and/or salts of .alpha.,.beta.-unsaturated carbonyl compounds. Conversion products find use, e.g., as feedstock and/or end-use chemicals.

  7. Highly enantioselective rhodium(I)-catalyzed carbonyl carboacylations initiated by C-C bond activation.

    Science.gov (United States)

    Souillart, Laetitia; Cramer, Nicolai

    2014-09-01

    The lactone motif is ubiquitous in natural products and pharmaceuticals. The Tishchenko disproportionation of two aldehydes, a carbonyl hydroacylation, is an efficient and atom-economic access to lactones. However, these reaction types are limited to the transfer of a hydride to the accepting carbonyl group. The transfer of alkyl groups enabling the formation of CC bonds during the ester formation would be of significant interest. Reported herein is such asymmetric carbonyl carboacylation of aldehydes and ketones, thus affording complex bicyclic lactones in excellent enantioselectivities. The rhodium(I)-catalyzed transformation is induced by an enantiotopic CC bond activation of a cyclobutanone and the formed rhodacyclic intermediate reacts with aldehyde or ketone groups to give highly functionalized lactones. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Stereoselective Carbonyl Olefination with Fluorosulfoximines: Facile Access to Z or E Terminal Monofluoroalkenes.

    Science.gov (United States)

    Liu, Qinghe; Shen, Xiao; Ni, Chuanfa; Hu, Jinbo

    2017-01-09

    Terminal monofluoroalkenes are important structural motifs in the design of bioactive compounds, such as homeostasis regulators and mechanism-based enzyme inhibitors. However, it is difficult to control the stereoselectivity of known carbonyl olefination reactions, and olefin metathesis is limited to disubstituted terminal monofluoroalkenes. Although sulfoximines have been used extensively in organic synthesis, reports on their use in carbonyl olefination reactions have not appeared to date. Herein, we report highly stereoselective carbonyl monofluoroolefination with a fluorosulfoximine reagent. The potential of this method is demonstrated by the synthesis of MDL 72161 and by the late-stage monofluoromethylenation of complex molecules, such as haloperidol and steroid derivatives. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Ruthenium-complex catalyzed N-(cyclo)alkylation of aromatic amines with diols. Selective synthesis of N-(n-hydroixyalkyl)anilines of type PhNH(CH2)nOH and of some bioactive arylpiperazines,

    NARCIS (Netherlands)

    Koten, G. van; Abbenhuis, R.A.T.M.; Boersma, J.

    1998-01-01

    A new class of well-defined neutral mono-, and dicationic ruthenium(II) complexes containing a neutral terdentate donor system [C5H3N(CH2E)(2)-2,6] (E = PPh2 (PNP) or NMe2 (NN'N)) has been found effective as catalyst precursor in N-(cyclo)alkylation reactions of aromatic amines with diols

  10. Organocatalytic Hydrophosphonylation Reaction of Carbonyl Groups.

    Science.gov (United States)

    Herrera, Raquel P

    2017-09-01

    This revision is covering the limited examples reported for a pivotal strategy in the formation of C-P bonds such as the asymmetric organocatalytic hydrophosphonylation of carbonyl groups (Pudovik reaction). The scope and limitations, and the proposed mechanisms for the scarce different possibilities of asymmetric induction are also shown. The recent evolution and future trends of this undeveloped approach are commented. © 2017 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Spatiotemporal distribution of carbonyl compounds in China.

    Science.gov (United States)

    Ho, K F; Ho, Steven Sai Hang; Huang, R-J; Dai, W T; Cao, J J; Tian, Linwei; Deng, W J

    2015-02-01

    A sampling campaign was carried out at nine Chinese cities in 2010/2011. Fifteen monocarbonyls (C# = 1-9) were quantified. Temperature is the rate-determining factor of the summertime carbonyl levels. The carbonyl emissions in winter are mainly driven by the primary anthropogenic sources like automobile. A molar ratio of propionaldehyde to nonaldehyde is a barometer of the impact of atmospheric vegetation emission which suggesting that strong vegetation emissions exist in summer and high propionaldehyde abundance is caused by fossil fuel combustion in winter. Potential health risk assessment of formaldehyde and acetaldehyde was conducted and the highest cumulative risks were observed at Chengdu in summer and Wuhan in winter. Because of the strong photochemical reaction and large amount of anthropogenic emissions, high concentrations of carbonyl compounds were observed in Chengdu. The use of ethanol-blended gasoline in Wuhan is the key reason of acetaldehyde emission and action should be taken to avoid potential health risks. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Carbonyl Compounds Generated from Electronic Cigarettes

    Directory of Open Access Journals (Sweden)

    Kanae Bekki

    2014-10-01

    Full Text Available Electronic cigarettes (e-cigarettes are advertised as being safer than tobacco cigarettes products as the chemical compounds inhaled from e-cigarettes are believed to be fewer and less toxic than those from tobacco cigarettes. Therefore, continuous careful monitoring and risk management of e-cigarettes should be implemented, with the aim of protecting and promoting public health worldwide. Moreover, basic scientific data are required for the regulation of e-cigarette. To date, there have been reports of many hazardous chemical compounds generated from e-cigarettes, particularly carbonyl compounds such as formaldehyde, acetaldehyde, acrolein, and glyoxal, which are often found in e-cigarette aerosols. These carbonyl compounds are incidentally generated by the oxidation of e-liquid (liquid in e-cigarette; glycerol and glycols when the liquid comes in contact with the heated nichrome wire. The compositions and concentrations of these compounds vary depending on the type of e-liquid and the battery voltage. In some cases, extremely high concentrations of these carbonyl compounds are generated, and may contribute to various health effects. Suppliers, risk management organizations, and users of e-cigarettes should be aware of this phenomenon.

  13. Palladium-catalyzed Reppe carbonylation.

    Science.gov (United States)

    Kiss, G

    2001-11-01

    PdX2L2/L/HA (A = weakly coordinating anion, L = phosphine) complexes are active catalysts in the hydroesterification of alkenes, alkynes, and conjugated dienes. Shell, the only major corporate player in the field, recently developed two very active catalyst systems tailored to the hydroesterification of either alkenes or alkynes. The hydroesterification of propyne with their Pd(OAc)2/PN/HA (PN = (2-pyridyl)diphenylphosphine, HA = strong acid with weakly coordinating anion, like methanesulfonic acid) catalyst has been declared commercially ready. However, despite the significant progress in the activity of Pd-hydroesterification catalysts, further improvements are warranted. Thus, for example, activity maintenance still seems to be an issue. Homogeneous Pd catalysts are prone to a number of deactivation reactions. Activity and stability promoters are often corrosive and add to the complexity of the system, making it less attractive. Nonetheless, the versatility of the process and its tolerance toward the functional groups of substrates should appeal especially to the makers of specialty products. Although hydroesterification yields esters from alkenes, alkynes, and dienes in fewer steps than hydroformylation does, the latter has some advantages at the current state of the art. (1) Hydroformylation catalysts, particularly some recently published phosphine-modified Rh systems, can achieve very high regioselectivity for the linear product that hydroesterification catalysts cannot match yet. By analogy with hydroformylation, bulkier ligands ought to be tested in hydroesterification to increase normal-ester selectivity. (2) Hydroformylation is proven, commercial. Hydroesterification can only replace it if it can provide significant economic incentives. Similar or just marginally better performance could not justify the cost of development of a new technology. (3) Hydroesterification requires pure CO while hydroformylation uses syngas, a mixture of CO and H2. The latter

  14. 3-Methylindole-Based Tripodal Tetraphosphine Ruthenium Complexes in N2 Coordination and Reduction and Formic Acid Dehydrogenation

    Directory of Open Access Journals (Sweden)

    Fenna F. van de Watering

    2017-10-01

    Full Text Available The ruthenium(II complexes RuCl2L1H, RuCl2L1CF3, RuCl2L1OMe and RuCl2L2H were synthesized from [Ru(η6-benzeneCl(μ-Cl]2 and the corresponding tripodal tris-3-methylindolephosphine-based ligands L1H, L1CF3, L1OMe, and L2H. Stoichiometric reduction of these complexes with KC8 yielded the corresponding ruthenium(0 dinitrogen complexes. The latter complexes were studied in the N2 reduction with chlorosilanes and KC8, yielding stoichiometric amounts of the silylamines. The synthesized ruthenium(II complexes are also active catalysts for the formic acid dehydrogenation reaction.

  15. Millimeter wave spectra of carbonyl cyanide

    Science.gov (United States)

    Bteich, S. B.; Tercero, B.; Cernicharo, J.; Motiyenko, R. A.; Margulès, L.; Guillemin, J.-C.

    2016-07-01

    Context. More than 30 cyanide derivatives of simple organic molecules have been detected in the interstellar medium, but only one dicarbonitrile has been found and that very recently. There is still a lack of high-resolution spectroscopic data particularly for dinitriles derivatives. The carbonyl cyanide molecule is a new and interesting candidate for astrophysical detection. It could be formed by the reaction of CO and CN radicals, or by substitution of the hydrogen atom by a cyano group in cyanoformaldehyde, HC(=O)CN, that has already been detected in the interstellar medium. Aims: The available data on the rotational spectrum of carbonyl cyanide is limited in terms of quantum number values and frequency range, and does not allow accurate extrapolation of the spectrum into the millimeter-wave range. To provide a firm basis for astrophysical detection of carbonyl cyanide we studied its millimeter-wave spectrum. Methods: The rotational spectrum of carbonyl cyanide was measured in the frequency range 152-308 GHz and analyzed using Watson's A- and S-reduction Hamiltonians. Results: The ground and first excited state of v5 vibrational mode were assigned and analyzed. More than 1100 distinct frequency lines of the ground state were fitted to produce an accurate set of rotational and centrifugal distortion constants up to the eighth order. The frequency predictions based on these constants should be accurate enough for astrophysical searches in the frequency range up to 500 GHz and for transition involving energy levels with J ≤ 100 and Ka ≤ 42. Based on the results we searched for interstellar carbonyl cyanide in available observational data without success. Thus, we derived upper limits to its column density in different sources. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2011.0.00009.SV. ALMA is a partnership of ESO (representing its member states), NSF (USA), and NINS (Japan) with NRC (Canada), NSC, and ASIAA (Taiwan), and KASI (Republic of

  16. Validation of protein carbonyl measurement: A multi-centre study

    Directory of Open Access Journals (Sweden)

    Edyta Augustyniak

    2015-04-01

    Full Text Available Protein carbonyls are widely analysed as a measure of protein oxidation. Several different methods exist for their determination. A previous study had described orders of magnitude variance that existed when protein carbonyls were analysed in a single laboratory by ELISA using different commercial kits. We have further explored the potential causes of variance in carbonyl analysis in a ring study. A soluble protein fraction was prepared from rat liver and exposed to 0, 5 and 15 min of UV irradiation. Lyophilised preparations were distributed to six different laboratories that routinely undertook protein carbonyl analysis across Europe. ELISA and Western blotting techniques detected an increase in protein carbonyl formation between 0 and 5 min of UV irradiation irrespective of method used. After irradiation for 15 min, less oxidation was detected by half of the laboratories than after 5 min irradiation. Three of the four ELISA carbonyl results fell within 95% confidence intervals. Likely errors in calculating absolute carbonyl values may be attributed to differences in standardisation. Out of up to 88 proteins identified as containing carbonyl groups after tryptic cleavage of irradiated and control liver proteins, only seven were common in all three liver preparations. Lysine and arginine residues modified by carbonyls are likely to be resistant to tryptic proteolysis. Use of a cocktail of proteases may increase the recovery of oxidised peptides. In conclusion, standardisation is critical for carbonyl analysis and heavily oxidised proteins may not be effectively analysed by any existing technique.

  17. Carbonyl Emissions from Gasoline and Diesel Motor Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Destaillats, Hugo; Jakober, Chris A.; Robert, Michael A.; Riddle, Sarah G.; Destaillats, Hugo; Charles, M. Judith; Green, Peter G.; Kleeman, Michael J.

    2007-12-01

    Carbonyls from gasoline powered light-duty vehicles (LDVs) and heavy-duty diesel powered vehicles (HDDVs) operated on chassis dynamometers were measured using an annular denuder-quartz filter-polyurethane foam sampler with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine derivatization and chromatography-mass spectrometry analyses. Two internal standards were utilized based on carbonyl recovery, 4-fluorobenzaldehyde forcarbonyls and 6-fluoro-4-chromanone for>_C8 compounds. Gas- and particle-phase emissions for 39 aliphatic and 20 aromatic carbonyls ranged from 0.1 ? 2000 ?g/L fuel for LDVs and 1.8 - 27000 mu g/L fuel for HDDVs. Gas-phase species accounted for 81-95percent of the total carbonyls from LDVs and 86-88percent from HDDVs. Particulate carbonyls emitted from a HDDV under realistic driving conditions were similar to concentrations measured in a diesel particulate matter (PM) standard reference material. Carbonyls accounted for 19percent of particulate organic carbon (POC) emissions from low-emission LDVs and 37percent of POC emissions from three-way catalyst equipped LDVs. This identifies carbonyls as one of the largest classes of compounds in LDV PM emissions. The carbonyl fraction of HDDV POC was lower, 3.3-3.9percent depending upon operational conditions. Partitioning analysis indicates the carbonyls had not achieved equilibrium between the gas- and particle-phase under the dilution factors of 126-584 used in the current study.

  18. Reactions of rhodium(I) carbonyl chloride with olefins

    International Nuclear Information System (INIS)

    Varshavskii, Yu.S.; Kiseleva, N.V.; Cherkasova, T.G.; Buzina, N.A.; Bresler, L.S.

    1987-01-01

    The reactions of [Rh(CO) 2 Cl] 2 (Y 0 ) with cyclooctene and several other olefins (1-heptene, 1-hexene, ethylene, and cyclohexene) have been studied by IR and 13 C NMR spectroscopy. The main reaction products are the binuclear complexes Rh 2 L(CO) 3 Cl 2 (Y 1 ) and [RhL(CO)Cl] 2 (Y 2 ), where L denotes the olefin. The extent of replacement of the carbonyl groups depends on the nature of the olefin and the conditions under which the reaction is carried out (the L:Rh ratio and the removal of CO from the reaction sphere). The liquid olefins form the following series according to their ability to replace the carbonyl groups: C 8 H 14 > C 7 H 14 , C 6 H 12 > C 6 H 10 . In the presence of an excess of C 8 H 14 , Y 2 disproportionates with the formation of a dicarbonyl product, which presumably corresponds to the formula Rh(C 8 H 14 ) 2 (CO) 2 Cl (a pentacoordinate complex with a trigonal-bipyramidal structure). The 13 C signal in the NMR spectrum of a solution of Y 2 in C 8 H 14 is a singlet with σ( 13 C) 180.3 ppm, which is an indication of the rapid exchange of the carbonyl groups. Rapid exchange of the CO ligands is also observed in solutions of Y 0 in the olefins (with the exception of C 6 H 10 ). For example, the 13 C signal in the spectrum of a solution of Y 0 in C 8 H 14 is a singlet with σ( 13 C) 179.8 ppm. The spectrum of Y 0 in C 6 H 10 is a doublet with σ( 13 C) = 178.5 ppm and 1 J(CRh) = 76.3 Hz. A scheme for the interaction of Y 0 with olefins based on the conception of the trans antagonism of π-acceptor ligands has been proposed

  19. The magnetorheological fluid of carbonyl iron suspension blended with grafted MWCNT or graphene

    Science.gov (United States)

    Rwei, Syang-Peng; Ranganathan, Palraj; Chiang, Whe-Yi; Wang, Tza-Yi

    2017-12-01

    In this work, the magnetorheological (MR) fluids containing MWCNT/CI (carbonyl iron) complex and graphene/CI complex were prepared and have the better dispersity in silicone oil than CI powders alone. 1, 4-Aminobenzoic acid (PABA) was used as a grafting agent to modify CI powders to have NH2-end-group so that such nanoparticles can adsorb to acid-treated MWCNT or graphene via attraction of NH2 and COOH groups. The MWCNT/CI complex and graphene/CI complex have a structure of carbonyl iron nanoparticles adsorbed to MWCNT and graphene by self assembly, respectively. Because the carbonyl iron particles possessing magnetic permeability in nanometer scale adsorb to MWCNT or graphene which usually has a nanometer-scaled diameter and a micrometer-scaled length in this work, the dispersity of MWCNT/CI or graphene/CI complex in silicone oil is superior than the previous report [15] that the micrometer-scaled carbonyl iron microspheres were coated with multiwalled carbon nanotubes. Among CI (unmodified), MWCNT/CI and graphene/CI, graphene/CI has the best dispersity while MWCNT/CI still has the better dispersity than unmodified CI. At the temperature T = 300 K, the saturation magnetizations of CI, MWCNT/CI, graphene/CI are 208, 211 emu/g, and 204 emu/g, respectively, indicating that MWCNT/CI complex and graphene/CI complex still maintain the saturation magnetization as high as CI without being interfered by the blended MWCNT or graphene. A wide dynamic range of the yield stress adjusted through varying the electric current can be achieved by the MR fluids containing 69 wt% MWCNT/CI and graphene/CI which is useful in a shock absorber or damper. The result of the yield stress indicates the suspended MWCNT/CI particles are oriented more easily toward the direction perpendicular to the flow direction to block the flow stream lines.

  20. Acute inhalation toxicity of carbonyl sulfide

    Energy Technology Data Exchange (ETDEWEB)

    Benson, J.M.; Hahn, F.F.; Barr, E.B. [and others

    1995-12-01

    Carbonyl sulfide (COS), a colorless gas, is a side product of industrial procedures sure as coal hydrogenation and gasification. It is structurally related to and is a metabolite of carbon disulfide. COS is metabolized in the body by carbonic anhydrase to hydrogen sulfide (H{sub 2}S), which is thought to be responsible for COS toxicity. No threshold limit value for COS has been established. Results of these studies indicate COS (with an LC{sub 50} of 590 ppm) is slightly less acutely toxic than H{sub 2}S (LC{sub 50} of 440 ppm).

  1. Pattern of occurrence and occupancy of carbonylation sites in proteins

    DEFF Research Database (Denmark)

    Rao, R Shyama Prasad; Møller, Ian Max

    2011-01-01

    sites. Comparison of metal-catalyzed oxidation of two closely related proteins indicates that this type of carbonylation might not be very specific in proteins. Interestingly, carbonylated sites show a very strong tendency to cluster together in the protein primary sequence hinting at some sort......Proteins are targets for modification by reactive oxygen species, and carbonylation is an important irreversible modification that increases during oxidative stress. While information on protein carbonylation is accumulating, its pattern is not yet understood. We have made a meta...

  2. Ruthenium(II) tris(2,2'-bipyridine) chelate as a chemiluminophore in extrinsic lyoluminescences of aluminium and magnesium in aqueous solution

    International Nuclear Information System (INIS)

    Jiang Qinghong; Kotiranta, Miia; Langel, Kaarina; Suomi, Johanna; Hakansson, Markus; Spehar, Anna-Maria; Ala-Kleme, Timo; Eskola, Jarkko; Kulmala, Sakari

    2005-01-01

    Ruthenium(II) tris(2,2'-bipyridine) chelate shows chemiluminescence (CL) both during dissolution of metallic aluminium in alkaline conditions, and during dissolution of magnesium metal in acidic conditions. The presence of peroxodisulfate ions strongly enhances the CL. Magnesium system provides considerably better detectability of the present chelate giving linear calibration plot spanning over many orders of magnitude of concentration down to subnanomolar concentration levels. The possible primary species generated and luminescence mechanisms are shortly discussed

  3. A multi-target caffeine derived rhodium(i) N-heterocyclic carbene complex: evaluation of the mechanism of action.

    Science.gov (United States)

    Zhang, Jing-Jing; Muenzner, Julienne K; Abu El Maaty, Mohamed A; Karge, Bianka; Schobert, Rainer; Wölfl, Stefan; Ott, Ingo

    2016-08-16

    A rhodium(i) and a ruthenium(ii) complex with a caffeine derived N-heterocyclic carbene (NHC) ligand were biologically investigated as organometallic conjugates consisting of a metal center and a naturally occurring moiety. While the ruthenium(ii) complex was largely inactive, the rhodium(i) NHC complex displayed selective cytotoxicity and significant anti-metastatic and in vivo anti-vascular activities and acted as both a mammalian and an E. coli thioredoxin reductase inhibitor. In HCT-116 cells it increased the reactive oxygen species level, leading to DNA damage, and it induced cell cycle arrest, decreased the mitochondrial membrane potential, and triggered apoptosis. This rhodium(i) NHC derivative thus represents a multi-target compound with promising anti-cancer potential.

  4. Electromagnetic properties of carbonyl iron and their microwave ...

    Indian Academy of Sciences (India)

    Administrator

    The aim of this paper is to develop a novel thin micro- wave absorber with good absorbing performance in wide bandwidth and lightweight. So we investigated the micro- wave absorbing characterization of silicone rubber using carbonyl iron as filler. Carbonyl iron can be widely used in the field of electromagnetic shielding ...

  5. Bifunctional dendrons for multiple carbohydrate presentation via carbonyl chemistry

    Directory of Open Access Journals (Sweden)

    Davide Bini

    2014-07-01

    Full Text Available The synthesis of new dendrons of the generations 0, 1 and 2 with a double bond at the focal point and a carbonyl group at the termini has been carried out. The carbonyl group has been exploited for the multivalent conjugation to a sample saccharide by reductive amination and alkoxyamine conjugation.

  6. Synthesis and detection of a seaborgium carbonyl complex

    NARCIS (Netherlands)

    Even, J.; Yakushev, A.; Duellmann, Ch E.; Haba, H.; Asai, M.; Sato, T. K.; Brand, H.; Di Nitto, A.; Eichler, R.; Fan, F. L.; Hartmann, W.; Huang, M.; Jaeger, E.; Kaji, D.; Kanaya, J.; Kaneya, Y.; Khuyagbaatar, J.; Kindler, B.; Kratz, J. V.; Krier, J.; Kudou, Y.; Kurz, N.; Lommel, B.; Miyashita, S.; Morimoto, K.; Morita, K.; Murakami, M.; Nagame, Y.; Nitsche, H.; Ooe, K.; Qin, Z.; Schaedel, M.; Steiner, J.; Sumita, T.; Takeyama, M.; Tanaka, K.; Toyoshima, A.; Tsukada, K.; Tuerler, A.; Usoltsev, I.; Wakabayashi, Y.; Wang, Y.; Wiehl, N.; Yamaki, S.

    2014-01-01

    Experimental investigations of transactinoide elements provide benchmark results for chemical theory and probe the predictive power of trends in the periodic table. So far, in gas-phase chemical reactions, simple inorganic compounds with the transactinoide in its highest oxidation state have been

  7. Carbonyl-Olefin Exchange Reaction: Present State and Outlook

    Science.gov (United States)

    Kalinova, Radostina; Jossifov, Christo

    The carbonyl-olefin exchange reaction (COER) is a new reaction between carbonyl group and olefin double bond, which has a formal similarity with the olefin metathesis (OM) - one carbon atom in the latter is replaced with an oxygen atom. Till now the new reaction is performed successfully only when the two functional groups (carbonyl group and olefin double bond) are in one molecule and are conjugated. The α, β-unsaturated carbonyl compounds (substituted propenones) are the compounds with such a structure. They polymerize giving substituted polyacetylenes. The chain propagation step of this polymerization is in fact the COER. The question arises: is it possible the COER to take place when the two functional groups are not in one molecule and are not conjugated, and could this reaction became an alternative of the existing carbonyl olefination reactions?

  8. Optimized biotin-hydrazide enrichment and mass spectrometry analysis of peptide carbonyls

    DEFF Research Database (Denmark)

    Havelund, Jesper F.; Wojdyla, K; Jensen, O. N.

    Irreversible cell damage through protein carbonylation is the result of reaction with reactive oxygen species (ROS) and has been coupled to many diseases. The precise molecular consequences of protein carbonylation, however, are still not clear. The localization of the carbonylated amino acid is ...... modifications are isobaric to carbonylation and it is often challenging to detect the weaker signal from carbonylated peptides necessitating enrichment step. We here present an optimized method for the enrichment of carbonylated peptides....

  9. Catalyst Initiation in the Oscillatory Carbonylation Reaction

    Directory of Open Access Journals (Sweden)

    Katarina Novakovic

    2011-01-01

    Full Text Available Palladium(II iodide is used as a catalyst in the phenylacetylene oxidative carbonylation reaction that has demonstrated oscillatory behaviour in both pH and heat of reaction. In an attempt to extract the reaction network responsible for the oscillatory nature of this reaction, the system was divided into smaller parts and they were studied. This paper focuses on understanding the reaction network responsible for the initial reactions of palladium(II iodide within this oscillatory reaction. The species researched include methanol, palladium(II iodide, potassium iodide, and carbon monoxide. Several chemical reactions were considered and applied in a modelling study. The study revealed the significant role played by traces of water contained in the standard HPLC grade methanol used.

  10. Composition tunable cobalt–nickel and cobalt–iron alloy nanoparticles below 10 nm synthesized using acetonated cobalt carbonyl

    International Nuclear Information System (INIS)

    Schooneveld, Matti M. van; Campos-Cuerva, Carlos; Pet, Jeroen; Meeldijk, Johannes D.; Rijssel, Jos van; Meijerink, Andries; Erné, Ben H.; Groot, Frank M. F. de

    2012-01-01

    A general organometallic route has been developed to synthesize Co x Ni 1−x and Co x Fe 1−x alloy nanoparticles with a fully tunable composition and a size of 4–10 nm with high yield. In contrast to previously reported synthesis methods using dicobalt octacarbonyl (Co 2 (CO) 8 ), here the cobalt–cobalt bond in the carbonyl complex is first broken with anhydrous acetone. The acetonated compound, in the presence of iron carbonyl or nickel acetylacetonate, is necessary to obtain small composition tunable alloys. This new route and insights will provide guidelines for the wet-chemical synthesis of yet unmade bimetallic alloy nanoparticles.

  11. High throughput assay for evaluation of reactive carbonyl scavenging capacity.

    Science.gov (United States)

    Vidal, N; Cavaille, J P; Graziani, F; Robin, M; Ouari, O; Pietri, S; Stocker, P

    2014-01-01

    Many carbonyl species from either lipid peroxidation or glycoxidation are extremely reactive and can disrupt the function of proteins and enzymes. 4-hydroxynonenal and methylglyoxal are the most abundant and toxic lipid-derived reactive carbonyl species. The presence of these toxics leads to carbonyl stress and cause a significant amount of macromolecular damages in several diseases. Much evidence indicates trapping of reactive carbonyl intermediates may be a useful strategy for inhibiting or decreasing carbonyl stress-associated pathologies. There is no rapid and convenient analytical method available for the assessment of direct carbonyl scavenging capacity, and a very limited number of carbonyl scavengers have been identified to date, their therapeutic potential being highlighted only recently. In this context, we have developed a new and rapid sensitive fluorimetric method for the assessment of reactive carbonyl scavengers without involvement glycoxidation systems. Efficacy of various thiol- and non-thiol-carbonyl scavenger pharmacophores was tested both using this screening assay adapted to 96-well microplates and in cultured cells. The scavenging effects on the formation of Advanced Glycation End-product of Bovine Serum Albumin formed with methylglyoxal, 4-hydroxynonenal and glucose-glycated as molecular models were also examined. Low molecular mass thiols with an α-amino-β-mercaptoethane structure showed the highest degree of inhibitory activity toward both α,β-unsaturated aldehydes and dicarbonyls. Cysteine and cysteamine have the best scavenging ability toward methylglyoxal. WR-1065 which is currently approved for clinical use as a protective agent against radiation and renal toxicity was identified as the best inhibitor of 4-hydroxynonenal.

  12. High throughput assay for evaluation of reactive carbonyl scavenging capacity

    Directory of Open Access Journals (Sweden)

    N. Vidal

    2014-01-01

    Full Text Available Many carbonyl species from either lipid peroxidation or glycoxidation are extremely reactive and can disrupt the function of proteins and enzymes. 4-hydroxynonenal and methylglyoxal are the most abundant and toxic lipid-derived reactive carbonyl species. The presence of these toxics leads to carbonyl stress and cause a significant amount of macromolecular damages in several diseases. Much evidence indicates trapping of reactive carbonyl intermediates may be a useful strategy for inhibiting or decreasing carbonyl stress-associated pathologies. There is no rapid and convenient analytical method available for the assessment of direct carbonyl scavenging capacity, and a very limited number of carbonyl scavengers have been identified to date, their therapeutic potential being highlighted only recently. In this context, we have developed a new and rapid sensitive fluorimetric method for the assessment of reactive carbonyl scavengers without involvement glycoxidation systems. Efficacy of various thiol- and non-thiol-carbonyl scavenger pharmacophores was tested both using this screening assay adapted to 96-well microplates and in cultured cells. The scavenging effects on the formation of Advanced Glycation End-product of Bovine Serum Albumin formed with methylglyoxal, 4-hydroxynonenal and glucose-glycated as molecular models were also examined. Low molecular mass thiols with an α-amino-β-mercaptoethane structure showed the highest degree of inhibitory activity toward both α,β-unsaturated aldehydes and dicarbonyls. Cysteine and cysteamine have the best scavenging ability toward methylglyoxal. WR-1065 which is currently approved for clinical use as a protective agent against radiation and renal toxicity was identified as the best inhibitor of 4-hydroxynonenal.

  13. Light induced electron transfer reactions of metal complexes

    International Nuclear Information System (INIS)

    Sutin, N.; Creutz, C.

    1980-01-01

    Properties of the excited states of tris(2,2'-bipyridine) and tris(1,10-phenanthroline) complexes of chromium(III), iron(II), ruthenium(II), osmium(II), rhodium(III), and iridium(III) are described. The electron transfer reactions of the ground and excited states are discussed and interpreted in terms of the driving force for the reaction and the distortions of the excited states relative to the corresponding ground states. General considerations relevant to the conversion of light into chemical energy are presented and progress in the use of polypyridine complexes to effect the light decomposition of water into hydrogen and oxygen is reviewed

  14. 16th Carbonyl Metabolism Meeting: from enzymology to genomics

    Directory of Open Access Journals (Sweden)

    Maser Edmund

    2012-12-01

    Full Text Available Abstract The 16th International Meeting on the Enzymology and Molecular Biology of Carbonyl Metabolism, Castle of Ploen (Schleswig-Holstein, Germany, July 10–15, 2012, covered all aspects of NAD(P-dependent oxido-reductases that are involved in the general metabolism of xenobiotic and physiological carbonyl compounds. Starting 30 years ago with enzyme purification, structure elucidation and enzyme kinetics, the Carbonyl Society members have meanwhile established internationally recognized enzyme nomenclature systems and now consider aspects of enzyme genomics and enzyme evolution along with their roles in diseases. The 16th international meeting included lectures from international speakers from all over the world.

  15. Characterization of Carbonyl Compounds in the Ambient Air of an Industrial City in Korea

    Directory of Open Access Journals (Sweden)

    Sung-Ok Baek

    2011-01-01

    Full Text Available The purpose of this study was to characterize spatial and temporal variations of carbonyl compounds in Gumi city, where a number of large electronic-industrial complexes are located. Carbonyl samples were collected at five sites in the Gumi area: three industrial, one commercial, and one residential area. Sampling was carried out throughout a year from December 2003 to November 2004. At one industrial site, samples were taken every six days, while those of the other sites were for seven consecutive days in every season. Each sample was collected for 150 minutes and at intervals of three times a day (morning, afternoon, and evening. A total of 476 samples were analyzed to determine 15 carbonyl compounds by the USEPA TO-11A (DNPH-cartridge/HPLC method. In general, acetaldehyde appeared to be the most abundant compound, followed by formaldehyde, and acetone+acrolein. Mean concentrations of acetaldehyde were two to three times higher in the industrial sites than in the other sites, with its maximum of 77.7 ppb. In contrast, ambient levels of formaldehyde did not show any significant difference between the industrial and non-industrial groups. Its concentrations peaked in summer probably due to the enhanced volatilization and photochemical reactivity. These results indicate significant emission sources of acetaldehyde in the Gumi industrial complexes. Mean concentrations of organic solvents (such as acetone+acrolein and methyl ethyl ketone were also significantly high in industrial areas. In conclusion, major sources of carbonyl compounds, including acetaldehyde, are strongly associated with industrial activities in the Gumi city area.

  16. Reactions of laser-ablated Co, Rh, and Ir with CO: Infrared spectra and density functional calculations of the metal carbonyl molecules, cations and anions in solid neon

    International Nuclear Information System (INIS)

    Zhou, M.; Andrews, L.

    1999-01-01

    Laser ablation produces metal atoms, cations, and electrons for reaction with CO during condensation in excess neon at 4 K. Infrared spectra are observed for the metal carbonyls, cations, and anions, which are identified from isotopic shifts ( 13 CO, C 18 O) and splittings using mixed isotopic precursors. Density functional calculations with pseudopotentials for Rh and Ir predict the observed carbonyl stretching frequencies within 1--2%. This characterization of the simple RhCO + , RhCO, and RhCO - (and Ir) species over a 350 cm -1 range provides a scale for comparison of larger catalytically active Rh and Ir carbonyl complexes in solution and on surfaces to estimate charge on the metal center. This work provides the first spectroscopic characterization of Rh and Ir carbonyl cations and anions except for the stable tetracarbonyl anions in solution

  17. Journal of Chemical Sciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 123; Issue 5 ... to study the decay of the excited states and the fast reactions of photo produced ... Ruthenium(II) carbonyl complexes containing chalconates and triphenylphosphine/arsine ..... Diversity in electrochemical oxidation of dihydroxybenzenes in the presence ...

  18. Instrument for Airborne Measurement of Carbonyl Sulfide, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Southwest Sciences proposes to develop small, low power instrumentation for the real-time direct measurement of carbonyl sulfide (OCS) in the atmosphere, especially...

  19. Instrument for Airborne Measurement of Carbonyl Sulfide, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — In this Phase II SBIR program, Southwest Sciences will continue the development of small, low power instrumentation for real-time direct measurement of carbonyl...

  20. Degradation of carbonyl hydroperoxides in the atmosphere and in combustion

    KAUST Repository

    Xing, Lili; Bao, Junwei Lucas; Wang, Zhandong; Zhang, Feng; Truhlar, Donald G.

    2017-01-01

    Oxygenates with carbonyl and hydroperoxy functional groups are important intermediates that are generated during the autooxidation of organic compounds in the atmosphere and during the autoignition of transport fuels. In the troposphere

  1. DNA damage by carbonyl stress in human skin cells

    International Nuclear Information System (INIS)

    Roberts, Michael J.; Wondrak, Georg T.; Laurean, Daniel Cervantes; Jacobson, Myron K.; Jacobson, Elaine L.

    2003-01-01

    Reactive carbonyl species (RCS) are potent mediators of cellular carbonyl stress originating from endogenous chemical processes such as lipid peroxidation and glycation. Skin deterioration as observed in photoaging and diabetes has been linked to accumulative protein damage from glycation, but the effects of carbonyl stress on skin cell genomic integrity are ill defined. In this study, the genotoxic effects of acute carbonyl stress on HaCaT keratinocytes and CF3 fibroblasts were assessed. Administration of the α-dicarbonyl compounds glyoxal and methylglyoxal as physiologically relevant RCS inhibited skin cell proliferation, led to intra-cellular protein glycation as evidenced by the accumulation of N ε -(carboxymethyl)-L-lysine (CML) in histones, and caused extensive DNA strand cleavage as assessed by the comet assay. These effects were prevented by treatment with the carbonyl scavenger D-penicillamine. Both glyoxal and methylglyoxal damaged DNA in intact cells. Glyoxal caused DNA strand breaks while methylglyoxal produced extensive DNA-protein cross-linking as evidenced by pronounced nuclear condensation and total suppression of comet formation. Glycation by glyoxal and methylglyoxal resulted in histone cross-linking in vitro and induced oxygen-dependent cleavage of plasmid DNA, which was partly suppressed by the hydroxyl scavenger mannitol. We suggest that a chemical mechanism of cellular DNA damage by carbonyl stress occurs in which histone glycoxidation is followed by reactive oxygen induced DNA stand breaks. The genotoxic potential of RCS in cultured skin cells and its suppression by a carbonyl scavenger as described in this study have implications for skin damage and carcinogenesis and its prevention by agents selective for carbonyl stress

  2. DNA damage by carbonyl stress in human skin cells

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, Michael J.; Wondrak, Georg T.; Laurean, Daniel Cervantes; Jacobson, Myron K.; Jacobson, Elaine L

    2003-01-28

    Reactive carbonyl species (RCS) are potent mediators of cellular carbonyl stress originating from endogenous chemical processes such as lipid peroxidation and glycation. Skin deterioration as observed in photoaging and diabetes has been linked to accumulative protein damage from glycation, but the effects of carbonyl stress on skin cell genomic integrity are ill defined. In this study, the genotoxic effects of acute carbonyl stress on HaCaT keratinocytes and CF3 fibroblasts were assessed. Administration of the {alpha}-dicarbonyl compounds glyoxal and methylglyoxal as physiologically relevant RCS inhibited skin cell proliferation, led to intra-cellular protein glycation as evidenced by the accumulation of N{sup {epsilon}}-(carboxymethyl)-L-lysine (CML) in histones, and caused extensive DNA strand cleavage as assessed by the comet assay. These effects were prevented by treatment with the carbonyl scavenger D-penicillamine. Both glyoxal and methylglyoxal damaged DNA in intact cells. Glyoxal caused DNA strand breaks while methylglyoxal produced extensive DNA-protein cross-linking as evidenced by pronounced nuclear condensation and total suppression of comet formation. Glycation by glyoxal and methylglyoxal resulted in histone cross-linking in vitro and induced oxygen-dependent cleavage of plasmid DNA, which was partly suppressed by the hydroxyl scavenger mannitol. We suggest that a chemical mechanism of cellular DNA damage by carbonyl stress occurs in which histone glycoxidation is followed by reactive oxygen induced DNA stand breaks. The genotoxic potential of RCS in cultured skin cells and its suppression by a carbonyl scavenger as described in this study have implications for skin damage and carcinogenesis and its prevention by agents selective for carbonyl stress.

  3. Propheromones that release pheromonal carbonyl compounds in light.

    Science.gov (United States)

    Liu, X; Macaulay, E D; Pickett, J A

    1984-05-01

    Pheromonal carbonyl compounds; (Z)-11-hexadecanal, (E)-citral, and 2-heptanone were treated with six alcohols to give acetals or ketals, some of which acted as propheromones by releasing the pheromonal carbonyl compounds in ultraviolet or simulated sunlight. Highest yields of pheromone were obtained from adducts prepared witho-nitrobenzyl alcohol ando-nitrophenylethane-1,2-diol. Adducts from (Z)-11-hexadecenal and these two alcohols were employed in lures to catch diamondback moths,Plutella xylostella (L.).

  4. Dansyl labeling and bidimensional mass spectrometry to investigate protein carbonylation.

    Science.gov (United States)

    Palmese, Angelo; De Rosa, Chiara; Marino, Gennaro; Amoresano, Angela

    2011-01-15

    Carbonylation is a non-enzymatic irreversible post-translational modification. The adduction of carbonyl groups to proteins is due to the presence of excess of ROS in cells. Carbonylation of specific amino acid side chains is one of the most abundant consequences of oxidative stress; therefore, the determination of carbonyl groups content in proteins is regarded as a reliable way to estimate the cellular damage caused by oxidative stress. This paper reports a novel RIGhT (Reporter Ion Generating Tag) (A. Amoresano, G. Monti, C. Cirulli, G. Marino. Rapid Commun. Mass Spectrom. 2006, 20, 1400) approach for selective labeling of carbonyl groups in proteins using dansylhydrazide, coupled with selective analysis by bidimensional mass spectrometry. We first applied this approach to ribonuclease A and lysozyme as model proteins. According to the so-called 'gel-free procedures', the analysis is carried out at the level of peptides following tryptic digest of the whole protein mixture. Modified RNaseA was analyzed in combined MS(2) and MS(3) scan mode, to specifically select the dansylated species taking advantage of the dansyl-specific fragmentation pathways. This combination allowed us to obtain a significant increase in signal/noise ratio and a significant increase in sensitivity of analysis, due to the reduction of duty cycle of the mass spectrometer. The unique signal obtained was correlated to peptide 1-10 of RNaseA carbonylated and labeled by dansylhydrazide. This strategy represents the first method leading to the direct identification of the carbonylation sites in proteins, thus indicating the feasibility of this strategy to investigate protein carbonylation in a proteomic approach. Copyright © 2010 John Wiley & Sons, Ltd.

  5. Selective transformation of carbonyl ligands to organic molecules. Progress report, September 1, 1989--November 14, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Cutler, A.R.

    1992-05-12

    Studies on the carbonylation of ({eta}{sup 5}-indenyl)(L)(CO)Ru-R complexes (L = CO, PPh{sub 3}; R = CH{sub 2}OMe, CH{sub 3}) have been completed. Particularly noteworthy is that the methoxymethyl complexes readily transform to their acyl derivatives under mild conditions that leave their iron congeners inert towards CO. Surprisingly, even ({eta}{sup 5}-indenyl)(PPh{sub 3}){sub 2}Ru-CH{sub 3} carbonylates and gives ({eta}{sup 5}-indenyl)(PPh{sub 3})(CO)Ru-C(O)CH{sub 3}. Mechanistic studies on the ``non catalyzed`` hydrosilation of the manganese acyls (CO){sub 5}Mn-C(O)CH{sub 2}R (R = H, OCH{sub 3}, CH{sub 3}) with Et{sub 3}SiH and of cobalt acetyls (CO){sub 3}(PR{sub 3})CoC(O)CH{sub 3} with several monohydrosilanes have been completed. The cobalt acetyls cleanly give ethoxysilanes (not acetaldehyde), and the manganese acyls provide {alpha}-siloxyvinyl complexes Z-(CO){sub 5}Mn-C(OSiEt{sub 3})=CHR (R = H, CH{sub 3}, OCH{sub 3}). Carbonylation and protolytic cleavage of the latter generate pyruvoyl complexes (CO){sub 5}Mn-COCOR (R = CH{sub 3}, CH{sub 2}CH{sub 3}), formally the products of net ``double carbonylation`` sequences. Studies in progress are concerned with how manganese complexes as diverse as (CO){sub 5}Mn-Y [Y = C(O)R, R, BR - but not SiMe{sub 3} or Mn(CO){sub 5}] and ({eta}{sup 3}-C{sub 3}H{sub 5})Mn(CO){sub 2}L [but not CpMn(CO){sub 3} or CpMn(CO){sub 2}({eta}{sup 2}HSiR{sub 3})] function as efficient hydrosilation catalysts towards Cp(CO){sub 2}FeC(O)CH{sub 3}, for example. These reactions cleanly afford fully characterized {alpha}-siloxyethyl complexes Fp-CH(OSiR{sub 3})CH{sub 3} under conditions where typically Rh(1) hydrosilation catalysts are inactive. Several of these manganese complexes also catalytically hydrosilate organic esters, including lactones, to their ethers R-CH{sub 2}OR; these novel ester reductions occur quantitatively at room temperature and appear to be general in scope.

  6. New method to determine the total carbonyl functional group content in extractable particulate organic matter by tandem mass spectrometry.

    Science.gov (United States)

    Dron, J; Zheng, W; Marchand, N; Wortham, H

    2008-08-01

    A functional group analysis method was developed to determine the quantitative content of carbonyl functional groups in atmospheric particulate organic matter (POM) using constant neutral loss scanning-tandem mass spectrometry (CNLS-MS/MS). The neutral loss method consists in monitoring the loss of a neutral fragment produced by the fragmentation of a precursor ion in a collision cell. The only ions detected are the daughter ions resulting from the loss of the neutral fragment under study. Then, scanning the loss of a neutral fragment characteristic of a functional group enables the selective detection of the compounds bearing the chemical function under study within a complex mixture. The selective detection of carbonyl functional groups was achieved after derivatization with pentafluorophenylhydrazine (PFPH) by monitoring the neutral loss of C(6)F(5)N (181 amu), which was characteristic of a large panel of derivatized carbonyl compounds. The method was tested on 25 reference mixtures of different composition, all containing 24 carbonyl compounds at randomly determined concentrations. The repeatability and calibration tests were satisfying as they resulted in a relative standard deviation below 5% and a linear range between 0.01 and 0.65 mM with a calculated detection limit of 0.0035 mM. Also, the relative deviation induced by changing the composition of the mixture while keeping the total concentration of carbonyl functional groups constant was less than 20%. These reliability experiments demonstrate the high robustness of the developed procedure for accurate carbonyl functional group measurement, which was applied to atmospheric POM samples. Copyright (c) 2008 John Wiley & Sons, Ltd.

  7. Catalytic performance of heterogeneous Rh/C3N4 for the carbonylation of methanol

    Science.gov (United States)

    Budiman, Anatta Wahyu; Choi, Myoung Jae; Nur, Adrian

    2018-02-01

    The excess of water in homogeneous the carbonylation of methanol system could increase the amount of by-products formed through water-gas shift reaction and could accelerate the rusting of equipment. Many scientists tried to decrease the content of water in the carbonylation of methanol system by using lithium and iodide promoter that results a moderate catalytic activity in the water content at 2wt%. The heterogenized catalyst offers several distinct advantages such as it was enables increased catalyst concentration in the reaction mixture, which is directly proportional to acetic acid production rate, without the addition of an alkali iodide salt promoter. The heterogeneous catalyst also results in reduced by-product formation. This study is aimed to produce a novel catalyst (Rh/C3N4) with a high selectivity of acetic acid in a relatively lower water and halide content. This novel catalyst performs high conversion and selectivity of acetic acid as the result of the strong ionic bonding of melamine and rhodium complex species that was caused by the presence of methyl iodide species. The CO2 in feed gas significantly decreases the catalytic activity of Rh-melamine because of its inert characteristics. The kinetic test was performed as that the first order kinetic equation. The kinetic tests revealed the reaction route of the the carbonylation of methanol in this system was performed trough the methyl acetate.

  8. Vapor phase carbonylation of dimethyl ether and methyl acetate with supported transition metal catalysts

    International Nuclear Information System (INIS)

    Shikada, T.; Fujimoto, K.; Tominaga, H.O.

    1986-01-01

    The synthesis of acetic acid (AcOH) from methanol (MeOH) and carbon monoxide has been performed industrially in the liquid phase using a rhodium complex catalyst and an iodide promoter. The selectivity to AcOH is more than 99% under mild conditions (175 0 C, 28 atm). The homogeneous rhodium catalyst has been also effective for the synthesis of acetic anhydride (Ac 2 O) by carbonylation of dimethyl ether (DME) or methyl acetate (AcOMe). However, rhodium is one of the most expensive metals and its proved reserves are quite limited. It is highly desired, therefore, to develop a new catalyst as a substitute for rhodium. The authors have already reported that nickel supported on active carbon exhibits an excellent activity for the vapor phase carbonylation of MeOh in the presence of iodide promoter and under moderately pressurized conditions. In addition, corrosive attack on reactors by iodide compounds is expected to be negligible in the vapor phase system. In the present work, vapor phase carbonylation of DME and AcOMe on nickel-active carbon (Ni/A.C.) and molybdenum-active carbon (Mo/A.C.) catalysts was studied

  9. Dual triggering of DNA binding and fluorescence via photoactivation of a dinuclear ruthenium(II) arene complex

    Czech Academy of Sciences Publication Activity Database

    Magennis, S.W.; Habtemariam, A.; Nováková, Olga; Henry, J.B.; Meier, S.; Parsons, S.; Oswald, D.H.; Brabec, Viktor; Sadler, P.J.

    2007-01-01

    Roč. 46, č. 12 (2007), s. 5059-5068 ISSN 0020-1669 R&D Projects: GA ČR(CZ) GA203/06/1239; GA ČR(CZ) GA305/05/2030; GA AV ČR(CZ) 1QS500040581; GA AV ČR(CZ) KAN200200651 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : DNA * ruthenium * fluorescence Subject RIV: BO - Biophysics Impact factor: 4.123, year: 2007

  10. Arene ruthenium(II) complexes with 2-acetamidothiazole derived ligands: Synthesis, structural studies, antifouling and antibacterial properties

    Digital Repository Service at National Institute of Oceanography (India)

    Singh, K.S.; PrabhaDevi; Sawant, S.G.; Kaminsky, W.

    . Habtemariam, P. J. Sadler, Chem. Commun. (2005) 4764. 11    [35] A. Habtemariam, M. Melchart, R. Fernández, S. Parsons, I. D. H. Oswald, A. Parkin, F. P. A. Fabbiani, J. E. Davidson, A. Dawson, R. E. Aird, D. I. Jodrell, P. J. Sadler, J. Med. Chem.49...-matrix least-squares on F 2 Data / restraints / parameters 4455 / 0 / 215 Goodness-of-fit on F2 1.038 Final R indices [I>2sigma(I)] R1 = 0.0202, wR2 = 0.0415 R indices (all data) R1 = 0.0261, wR2 = 0.0436 Largest diff. peak and hole 0.431 and -0.388 e...

  11. Antiplasmodial activity of iron(II and ruthenium(II organometallic complexes against Plasmodium falciparum blood parasites

    Directory of Open Access Journals (Sweden)

    Nicolli Bellotti de Souza

    2015-01-01

    Full Text Available This work reports the in vitro activity against Plasmodium falciparumblood forms (W2 clone, chloroquine-resistant of tamoxifen-based compounds and their ferrocenyl (ferrocifens and ruthenocenyl (ruthenocifens derivatives, as well as their cytotoxicity against HepG2 human hepatoma cells. Surprisingly with these series, results indicate that the biological activity of ruthenocifens is better than that of ferrocifens and other tamoxifen-like compounds. The synthesis of a new metal-based compound is also described. It was shown, for the first time, that ruthenocifens are good antiplasmodial prototypes. Further studies will be conducted aiming at a better understanding of their mechanism of action and at obtaining new compounds with better therapeutic profile.

  12. New Ir Bis-Carbonyl Precursor for Water Oxidation Catalysis

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Daria L. [Department of Chemistry, Yale University, 225; Beltrán-Suito, Rodrigo [Department of Chemistry, Yale University, 225; Thomsen, Julianne M. [Department of Chemistry, Yale University, 225; Hashmi, Sara M. [Department of Chemical and Environmental; Materna, Kelly L. [Department of Chemistry, Yale University, 225; Sheehan, Stafford W. [Catalytic Innovations LLC, 70 Crandall; Mercado, Brandon Q. [Department of Chemistry, Yale University, 225; Brudvig, Gary W. [Department of Chemistry, Yale University, 225; Crabtree, Robert H. [Department of Chemistry, Yale University, 225

    2016-02-05

    This paper introduces IrI(CO)2(pyalc) (pyalc = (2-pyridyl)-2-propanoate) as an atom-efficient precursor for Ir-based homogeneous oxidation catalysis. This compound was chosen to simplify analysis of the water oxidation catalyst species formed by the previously reported Cp*IrIII(pyalc)OH water oxidation precatalyst. Here, we present a comparative study on the chemical and catalytic properties of these two precursors. Previous studies show that oxidative activation of Cp*Ir-based precursors with NaIO4 results in formation of a blue IrIV species. This activation is concomitant with the loss of the placeholder Cp* ligand which oxidatively degrades to form acetic acid, iodate, and other obligatory byproducts. The activation process requires substantial amounts of primary oxidant, and the degradation products complicate analysis of the resulting IrIV species. The species formed from oxidation of the Ir(CO)2(pyalc) precursor, on the other hand, lacks these degradation products (the CO ligands are easily lost upon oxidation) which allows for more detailed examination of the resulting Ir(pyalc) active species both catalytically and spectroscopically, although complete structural analysis is still elusive. Once Ir(CO)2(pyalc) is activated, the system requires acetic acid or acetate to prevent the formation of nanoparticles. Investigation of the activated bis-carbonyl complex also suggests several Ir(pyalc) isomers may exist in solution. By 1H NMR, activated Ir(CO)2(pyalc) has fewer isomers than activated Cp*Ir complexes, allowing for advanced characterization. Future research in this direction is expected to contribute to a better structural understanding of the active species. A diol crystallization agent was needed for the structure determination of 3.

  13. Ozone Effects on Protein Carbonyl Content in the Frontal ...

    Science.gov (United States)

    Oxidative stress (OS) plays an important role in susceptibility and disease in old age. Understanding age-related susceptibility is a critical part of community-based human health risk assessment of chemical exposures. There is growing concern over a common air pollutant, ozone (03), and adverse health effects including dysfunction of the pulmonary, cardiac, and nervous systems. The objective of this study was to test whether OS plays a role in the adverse effects caused by 03 exposure, and if so, if effects were age-dependent. We selected protein carbonyl as an indicator of OS because carbonyl content of cells is a useful indicator of oxidative protein damage and has been linked to chemical-induced adverse effects. Male Brown Norway rats (4, 12, and 24 months) were exposed to 03 (0,0.25 or 1 ppm) via inhalation for 6 h/day, 2 days per week for 13 weeks. Frontal cortex (FC) and cerebellum (CB) were dissected, quick frozen on dry ice, and stored at -80°C. Protein carbonyls were assayed using commercial kits. Hydrogen peroxide, a positive control, increased protein carbonyls in cortical tissue in vitro in a concentration-dependent manner. Significant effects of age on protein carbonyls in FC and a significant effect of age and 03 dose on protein carbonyls in CB were observed. In control rats, there was an age-dependent increase in protein carbonyls indicating increased OS in 12 and 24 month old rats compared to 4 month old rats. Although 03 increase

  14. Determination of Carbonyl Compounds in Exhaled Cigarette Smoke

    Directory of Open Access Journals (Sweden)

    Moldoveanu S

    2014-12-01

    Full Text Available This paper presents the findings on a quantitative evaluation of carbonyl levels in exhaled cigarette smoke from human subjects. The cigarettes evaluated include products with 5.0 mg ‘tar’, 10.6 mg ‘tar’ and 16.2 mg ‘tar’, where ‘tar’ is defined as the weight of total wet particulate matter (TPM minus the weight of nicotine and water, and the cigarettes are smoked following U.S. Federal Trade Commission (FTC recommendations. The measured levels of carbonyls in the exhaled smoke were compared with calculated yields of carbonyls in the inhaled smoke and a retention efficiency was obtained. The number of human subjects included a total of ten smokers for the 10.6 mg ‘tar’, five for the 16.2 mg ‘tar’, and five for the 5.0 mg ‘tar’ product, each subject smoking three cigarettes. The analyzed carbonyl compounds included several aldehydes (formaldehyde, acetaldehyde, acrolein, propionaldehyde, crotonaldehyde and n-butyraldehyde, and two ketones (acetone and 2-butanone. The smoke collection from the human subjects was vacuum assisted. Exhaled smoke was collected on Cambridge pads pretreated with a solution of dinitrophenylhydrazine (DNPH followed by high performance liquid chromatography (HPLC analysis of the dinitrophenylhydrazones of the carbonyl compounds. The cigarette butts from the smokers were collected and analyzed for nicotine. The nicotine levels for the cigarette butts from the smokers were used to calculate the level of carbonyls in the inhaled smoke, based on calibration curves. These were generated separately by analyzing the carbonyls in smoke and the nicotine in the cigarette butts obtained by machine smoking under different puffing regimes. The comparison of the level of carbonyl compounds in exhaled smoke with that from the inhaled smoke showed high retention of all the carbonyls. The retention of aldehydes was above 95% for all three different ‘tar’ levels cigarettes. The ketones were retained with a

  15. Emissions of carbonyl compounds from various cookstoves in China

    International Nuclear Information System (INIS)

    Zhang, J.; Smith, K.R.; Univ. of California, Berkeley, CA

    1999-01-01

    This paper presents a new database of carbonyl emission factors for commonly used cookstoves in China. The emission factors, reported both on a fuel-mass basis (mg/kg) and on a defined cooking-task basis (mg/task), were determined using a carbon balance approach for 22 types of fuel/stove combinations. These include various stoves using different species of crop residues and wood, kerosene, and several types of coals and gases. The results show that all the tested cookstoves produced formaldehyde and acetaldehyde and that the vast majority of the biomass stoves produced additional carbonyl compounds such as acetone, acrolein, propionaldehyde, crotonaldehyde, 2-butanone, isobutyraldehyde, butyraldehyde, isovaleraldehyde, valeraldehyde, hexaldehyde, benzaldehyde, o-tolualdehyde, m,p-tolualdehyde, and 2,4-dimethylbenzaldehyde. Carbonyls other than formaldehyde and acetaldehyde, however, were rarely generated by burning coal, coal gas, and natural gas. Kerosene and LPG stoves generated more carbonyl compounds than coal, coal gas, and natural gas stoves, but less than biomass stoves. Indoor levels of carbonyl compounds for typical village houses during cooking hours, estimated using a mass balance model and the measured emission factors, can be high enough to cause acute health effects documented for formaldehyde exposure, depending upon house parameters and individuals' susceptibility

  16. Copper-catalyzed 1,2-addition of α-carbonyl iodides to alkynes.

    Science.gov (United States)

    Xu, Tao; Hu, Xile

    2015-01-19

    β,γ-Unsaturated ketones are an important class of organic molecules. Herein, copper catalysis has been developed for the synthesis of β-γ-unsaturated ketones through 1,2-addition of α-carbonyl iodides to alkynes. The reactions exhibit wide substrate scope and high functional group tolerance. The reaction products are versatile synthetic intermediates to complex small molecules. The method was applied for the formal synthesis of (±)-trichostatin A, a histone deacetylase inhibitor. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Catalytic production of metal carbonyls from metal oxides

    Science.gov (United States)

    Sapienza, Richard S.; Slegeir, William A.; Foran, Michael T.

    1984-01-01

    This invention relates to the formation of metal carbonyls from metal oxides and specially the formation of molybdenum carbonyl and iron carbonyl from their respective oxides. Copper is used here in admixed form or used in chemically combined form as copper molybdate. The copper/metal oxide combination or combined copper is utilized with a solvent, such as toluene and subjected to carbon monoxide pressure of 25 atmospheres or greater at about 150.degree.-260.degree. C. The reducing metal copper is employed in catalytic concentrations or combined concentrations as CuMoO.sub.4 and both hydrogen and water present serve as promoters. It has been found that the yields by this process have been salutary and that additionally the catalytic metal may be reused in the process to good effect.

  18. Separation of Trace Amount Zn (II Using Additional Carbonyl and Carboxyl Groups Functionalized-Nano Graphene

    Directory of Open Access Journals (Sweden)

    A. Moghimi

    2013-01-01

    Full Text Available A novel and selective method for the fast determination of trace amounts of Zn(IIions in water samples has been developed.  The first additional carbonyl and carboxyl functionalized-nano graphene (SPFNano graphene. The presence of additional carbonyl and carboxyl groups located at the edge of the sheets makes GO sheets strongly hydrophilic, allowing them to readily swell and disperse in water. Based on these oxygen functionalities, different model structures of GO were used as absorbent for extraction of Zn (II   ions by solid phase extraction method. The complexes were eluted with HNO3 (2M10% V.V-1 methanol in acetone and determined the analyte by flame atomic absorption spectrometry.  The procedure is based on the selective formation of Zn (II at optimum pH by elution with organic eluents and determination by flame atomic absorption spectrometry. The method is based on complex formation on the surface of the ENVI-18 DISKTM disks modified carbonyl and carboxyl functionalized-nano graphene oxide molecules covalently bonded together followed by stripping of the retained species by minimum amounts of appropriate organic solvents. The elution is efficient and quantitative. The effect of potential interfering ions, pH, SPFNano graphene, amount, stripping solvent, and sample flow rate were also investigated. Under the optimal experimental conditions, the break-through volume was found to about 1000mL providing a preconcentration factor of 500. The maximum capacity of the disks was found to be 456± 3 µg for Zn2+.The limit of detection of the proposed method is 5ng per 1000mL.The method was applied to the extraction and recovery of Zn in different water samples.

  19. Nonlinear optical properties of systems based on ruthenium(II) tetra-15-crown-5-phthalocyaninate

    International Nuclear Information System (INIS)

    Grishina, A.D.; Gorbunova, Yu.G.; Enakieva, Yu.Yu.; Krivenko, T.V.; Savel'ev, V.V.; Vannikov, A.V.; Tsivadze, A.Yu.

    2008-01-01

    The third-order nonlinear optical properties of the ruthenium (II) complex with tetra-15-crown-5-phthalocyanine and axially coordinated triethylenediamine molecules (R 4 Pc)Ru(TED) 2 were analyzed by means of the z-scanning technique. A solution of (R 4 Pc)Ru(TED) 2 in tetrachloroethane was exposed to nanosecond laser pulses at a wavelength of 1064 nm. It was found that the third-order molecular polarizability of the Ru(II) complex is 4.5 x 10 -32 cm 4 /C (esu). The polarizability per molecule increases by a factor of 3.6 when the single molecule occurs in a supramolecular assembly of (R 4 Pc)Ru(TED) 2 complexes. The photoelectric and photorefractive properties at 1064 nm of polymer composites, determined by the supramolecular assemblies that exhibits optical absorption and photoelectric sensitivity in the near IR region, are reported [ru

  20. Study of reactivity of p-cymene ruthenium(II) dimer towards diphenyl ...

    Indian Academy of Sciences (India)

    Unknown

    The reaction of [{(η6-p-cymene)Ru(µ-Cl)}2Cl2] with functionalized phosphine viz, diphenyl-. 2-pyridylphosphine ... ing from the displacement of the p-cymene ligand. ... The structures of complexes 1 and 2 have been confirmed by single crystal.

  1. Metal-Diazo Radicals of α-Carbonyl Diazomethanes

    Science.gov (United States)

    Li, Feifei; Xiao, Longqiang; Liu, Lijian

    2016-03-01

    Metal-diazo radicals of α-carbonyl diazomethanes are new members of the radical family and are precursors to metal-carbene radicals. Herein, using electron paramagnetic resonance spectroscopy with spin-trapping, we detect diazo radicals of α-carbonyl diazomethanes, induced by [RhICl(cod)]2, [CoII(por)] and PdCl2, at room temperature. The unique quintet signal of the Rh-diazo radical was observed in measurements of α-carbonyl diazomethane adducts of [RhICl(cod)]2 in the presence of 5,5-dimethyl-pyrroline-1-N-oxide (DMPO). DFT calculations indicated that 97.2% of spin density is localized on the diazo moiety. Co- and Pd-diazo radicals are EPR silent but were captured by DMPO to form spin adducts of DMPO-N• (triplet-of-sextets signal). The spin-trapping also provides a powerful tool for detection of metal-carbene radicals, as evidenced by the DMPO-trapped carbene radicals (DMPO-C•, sextet signal) and 2-methyl-2-nitrosopropane-carbene adducts (MNP-C•, doublet-of-triplets signal). The transformation of α-carbonyl diazomethanes to metal-carbene radicals was confirmed to be a two-step process via metal-diazo radicals.

  2. Carbonyl atmospheric reaction products of aromatic hydrocarbons in ambient air

    Science.gov (United States)

    Obermeyer, Genevieve; Aschmann, Sara M.; Atkinson, Roger; Arey, Janet

    To convert gaseous carbonyls to oximes during sampling, an XAD-4 resin denuder system pre-coated with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine and followed by analysis with methane positive chemical ionization gas chromatography/mass spectrometry was used to measure carbonyls in ambient air samples in Riverside, CA. In conjunction with similar analyses of environmental chamber OH radical-initiated reactions of o- and p-xylene, 1,2,4-trimethylbenzene, ethylbenzene, 4-hydroxy-2-butanone and 1,4-butanediol, we identified benzaldehyde, o-, m- and p-tolualdehyde and acetophenone and the dicarbonyls glyoxal, methylglyoxal, biacetyl, ethylglyoxal, 1,4-butenedial, 3-hexene-2,5-dione, 3-oxo-butanal, 1,4-butanedial and malonaldehyde in the ambient air samples. As discussed, these carbonyls and dicarbonyls can be formed from the OH radical-initiated reactions of aromatic hydrocarbons and other volatile organic compounds emitted into the atmosphere, and we conclude that in situ atmospheric formation is a major source of these carbonyls in our Riverside, CA, ambient air samples.

  3. Plasma protein carbonyl levels and breast cancer risk

    Czech Academy of Sciences Publication Activity Database

    Rössner ml., Pavel; Terry, M. B.; Gammon, M. D.; Agrawal, M.; Zhang, F. F.; Ferris, J.S.; Teitelbaum, S. L.; Eng, S. M.; Gaudet, M. M.; Neugut, A. I.; Santella, R. M.

    2007-01-01

    Roč. 11, č. 5 (2007), s. 1138-1148 ISSN 1582-1838 Institutional research plan: CEZ:AV0Z50390512 Keywords : oxidative stress * protein carbonyl * breast cancer Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 6.807, year: 2007

  4. cyclo-addition reaction of triplet carbonyl compounds to substituted ...

    Indian Academy of Sciences (India)

    Unknown

    cited state energy of the olefin must be higher than that of the ketone so that ... the first singlet and triplet1,3 (n, π*) excited state of the carbonyl compounds.3,4 ... of the oxetane via carbon–carbon and carbon–oxygen attacks. They found the ...

  5. Olefination of carbonyl compounds: modern and classical methods

    Energy Technology Data Exchange (ETDEWEB)

    Korotchenko, V N; Nenajdenko, Valentine G; Balenkova, Elizabeth S [Department of Chemistry, M.V. Lomonosov Moscow State University, Moscow (Russian Federation); Shastin, Aleksey V [Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka, Moscow Region (Russian Federation)

    2004-10-31

    The published data on the methods for alkene synthesis by olefination of carbonyl compounds are generalised and systematised. The main attention is given to the use of transition metals and organoelement compounds. The review covers the data on both classical and newly developed methods that are little known to chemists at large.

  6. Olefination of carbonyl compounds: modern and classical methods

    Science.gov (United States)

    Korotchenko, V. N.; Nenajdenko, Valentine G.; Balenkova, Elizabeth S.; Shastin, Aleksey V.

    2004-10-01

    The published data on the methods for alkene synthesis by olefination of carbonyl compounds are generalised and systematised. The main attention is given to the use of transition metals and organoelement compounds. The review covers the data on both classical and newly developed methods that are little known to chemists at large.

  7. Frustrated Lewis pairs-assisted reduction of carbonyl compounds

    DEFF Research Database (Denmark)

    Marek, Ales; Pedersen, Martin Holst Friborg

    2015-01-01

    An alternative and robust method for the reduction of carbonyl groups by frustrated Lewis pairs (FLPs) is reported in this paper. With its very mild reaction conditions, good to excellent yields, absolute regioselectivity and the non-metallic character of the reagent, it provides an excellent too...

  8. Synthesis and Photophysical and Electrochemical Properties of Functionalized Mono-, Bis-, and Trisanthracenyl Bridged Ru(II Bis(2,2′:6′,2″-terpyridine Charge Transfer Complexes

    Directory of Open Access Journals (Sweden)

    Adewale O. Adeloye

    2014-01-01

    Full Text Available With the aim of developing new molecular devices having long-range electron transfer in artificial systems and as photosensitizers, a series of homoleptic ruthenium(II bisterpyridine complexes bearing one to three anthracenyl units sandwiched between terpyridine and 2-methyl-2-butenoic acid group are synthesized and characterized. The complexes formulated as bis-4′-(9-monoanthracenyl-10-(2-methyl-2-butenoic acid terpyridyl ruthenium(II bis(hexafluorophosphate (RBT1, bis-4′-(9-dianthracenyl-10-(2-methyl-2-butenoic acid terpyridyl ruthenium(II bis(hexafluorophosphate (RBT2, and bis-4′-(9-trianthracenyl-10-(2-methyl-2-butenoic acid terpyridyl ruthenium(II bis(hexafluorophosphate (RBT3 were characterized by elemental analysis, FT-IR, UV-Vis, photoluminescence, 1H and 13C NMR spectroscopy, and electrochemical techniques by elemental analysis, FT-IR, UV-Vis, photoluminescence, 1H and 13C NMR spectroscopy, and electrochemical techniques. The cyclic voltammograms (CVs of (RBT1, (RBT2, and (RBT3 display reversible one-electron oxidation processes at E1/2 = 1.13 V, 0.71 V, and 0.99 V, respectively (versus Ag/AgCl. Based on a general linear correlation between increase in the length of π-conjugation bond and the molar extinction coefficients, the Ru(II bisterpyridyl complexes show characteristic broad and intense metal-to-ligand charge transfer (MLCT band absorption transitions between 480–600 nm, ε=9.45×103 M−1 cm−1, and appreciable photoluminescence spanning the visible region.

  9. Organometallic and Bioorganometallic Chemistry - Ferrocene and Metal Carbonyls

    Directory of Open Access Journals (Sweden)

    Čakić Semenčić, M.

    2011-02-01

    procedure to use metal atoms in organometallics as labelling agents for antigens (A in immunoassays (IA is called metalloimmunoassay (MIA, Cais, 1977. Carbonyl metalloimmunoassay (CMIA is a heterogeneous competitive-type MIA using M-CO complexes as tracers, and FT-IR spectroscopy for quantification. This procedure allowed the simultaneous multiple IA reaching the fentomole concentration (Jaouen, 2000. From the variety of bioorganometallics synthesis and properties of the simple ferrocene-amino acids/peptides conjugates and ferrocene labelled carbohydrates, as well as the structure and function determination of B12 vitamin are described in this review.

  10. Degradation of carbonyl hydroperoxides in the atmosphere and in combustion

    KAUST Repository

    Xing, Lili

    2017-10-12

    Oxygenates with carbonyl and hydroperoxy functional groups are important intermediates that are generated during the autooxidation of organic compounds in the atmosphere and during the autoignition of transport fuels. In the troposphere, the degradation of carbonyl hydroperoxides leads to low-vapor-pressure polyfunctional species that be taken into in cloud and fog droplets or to the formation of secondary organic aerosols (SOAs). In combustion, the fate of carbonyl hydroperoxides is important for the performance of advanced combustion engines, especially for autoignition. A key fate of the carbonyl hydroperoxides is reac-tion with OH radicals, for which kinetics data are experimentally unavailable. Here, we study 4-hydroperoxy-2-pentanone (CH3C(=O)CH2CH(OOH)CH3) as a model compound to clarify the kinetics of OH reactions with carbonyl hydroperoxides, in par-ticular H-atom abstraction and OH addition reactions. With a combination of electronic structure calculations, we determine previ-ously missing thermochemical data, and with multipath variational transition state theory (MP-VTST), a multidimensional tunnel-ing (MT) approximation, multiple-structure anharmonicity, and torsional potential anharmonicity we obtained much more accurate rate constants than the ones that can computed by conventional single-structure harmonic transition state theory (TST) and than the empirically estimated rate constants that are currently used in atmospheric and combustion modeling. The roles of various factors in determining the rates are elucidated. The pressure-dependent rate constants for the addition reaction are computed using system-specific quantum RRK theory. The calculated temperature range is 298-2400 K, and the pressure range is 0.01–100 atm. The accu-rate thermodynamic and kinetics data determined in this work are indispensable in the global modeling of SOAs in atmospheric science and in the detailed understanding and prediction of ignition properties of hydrocarbons

  11. Low pressure carbonylation of benzyl chloride = Die carbonylierung von benzylchlorid bei niedrigen drücken

    NARCIS (Netherlands)

    Luggenhorst, H.J.; Westerterp, K.R.

    1986-01-01

    For carbonylations, metal carbonyls, particularly cobalt and iron carbonyls, are often used as catalysts. These reactions take place under rather drastic reaction conditions, e.g. 200–300 °C and 60–100 MPa. In some patents it is stated that similar reactions using the same catalysts can also be

  12. Hydrothermal synthesis of carbonyl iron-carbon nanocomposite: Characterization and electromagnetic performance

    Directory of Open Access Journals (Sweden)

    Hakimeh Pourabdollahi

    Full Text Available In this research, the electromagnetic absorption properties of the carbonyl iron-carbon (CI/C nanocomposite prepared via hydrothermal reaction using glucose as carbon precursor was studied in the range of 8.2–12.4 GHz. In hydrothermal reaction, glucose solution containing CI particles, placed in autoclave for 4 h under 453 K. Using surface coating technology is a method that prevents Cl oxidation and improves CI electromagnetic absorption. The structure, morphology and magnetic performances of the prepared nanocomposites were characterized by X-ray diffraction (XRD, energy dispersive spectrometry (EDS, transmission electron microscopy (TEM and vibrating sample magnetometer (VSM. The electromagnetic properties including complex permittivity (εr, the permeability (µr, dielectric loss, magnetic loss, reflection loss, and attenuation constant were investigated using a vector network analyzer. For The CI/C nanocomposite, the bandwidth of −10 dB and −20 dB were obtained in the frequency range of 9.8–12.4 and 11.0–11.8 GHz, respectively. As well as, the reflection loss was −46.69 dB at the matching frequency of 11.5 GHz, when the matching thickness was 1.3 mm. While for CI particles the reflection loss for 4.4 mm thickness was −16.86 dB at the matching frequency of 12.3 GHz. The results indicate that the existence layer of carbon on carbonyl iron enhance the electromagnetic absorbing properties. Therefore, this nanocomposite can be suitable for in the radar absorbing coatings. Keywords: Hydrothermal synthesis, Carbonyl iron-carbon nanocomposite, Microwave absorption, Reflection loss

  13. Accumulation of carbonyls accelerates the formation of pentosidine, an advanced glycation end product: carbonyl stress in uremia.

    Science.gov (United States)

    Miyata, T; Ueda, Y; Yamada, Y; Izuhara, Y; Wada, T; Jadoul, M; Saito, A; Kurokawa, K; van Ypersele de Strihou, C

    1998-12-01

    Advanced glycation end product (AGE) formation is related to hyperglycemia in diabetes but not in uremia, because plasma AGE levels do not differ between diabetic and nondiabetic hemodialysis patients. The mechanism of this phenomenon remains elusive. Previously, it was suggested that elevation of AGE levels in uremia might result from the accumulation of unknown AGE precursors. The present study evaluates the in vitro generation of pentosidine, a well identified AGE structure. Plasma samples from healthy subjects and nondiabetic hemodialysis patients were incubated under air for several weeks. Pentosidine levels were determined at intervals by HPLC assay. Pentosidine rose to a much larger extent in uremic than in control plasma. Pentosidine yield, i.e., the change in pentosidine level between 0 and 4 wk divided by 28 d, averaged 0.172 nmol/ml per d in uremic versus 0.072 nmol/ml per d in control plasma (P aminoguanidine and OPB-9195, which inhibit the Maillard reaction, lowered pentosidine yield in both uremic and control plasma. When ultrafiltrated plasma was exposed to 2,4-dinitrophenylhydrazine, the yield of hydrazones, formed by interaction with carbonyl groups, was markedly higher in uremic than in control plasma. These observations strongly suggest that the pentosidine precursors accumulated in uremic plasma are carbonyl compounds. These precursors are unrelated to glucose or ascorbic acid, whose concentration is either normal or lowered in uremic plasma. They are also unrelated to 3-deoxyglucosone, a glucose-derived dicarbonyl compound whose level is raised in uremic plasma: Its addition to normal plasma fails to increase pentosidine yield. This study reports an elevated level of reactive carbonyl compounds ("carbonyl stress") in uremic plasma. Most have a lower than 5000 Da molecular weight and are thus partly removed by hemodialysis. Their effect on pentosidine generation can be inhibited by aminoguanidine or OPB-9195. Carbonyl stress might contribute to

  14. Rotational spectrum and structure of the carbonyl sulfide-trifluoromethane weakly bound dimer.

    Science.gov (United States)

    Serafin, Michal M; Peebles, Sean A

    2006-11-02

    Pure rotational spectra of five isotopomers of the 1:1 weakly bound complex formed between carbonyl sulfide and trifluoromethane (TFM) have been measured using Fourier transform microwave spectroscopy. The experimental rotational constants and dipole moment components are consistent with a structure of C(s) symmetry in which the dipole moment vectors of OCS and HCF(3) are aligned antiparallel and at an angle of about 40 degrees and with a center of mass separation of 3.965(26) A. The derived H...O distance is 2.90(5) A, which is up to 0.6 A longer than is seen in other similar TFM complexes exhibiting C-H...O interactions. Ab initio calculations at the MP2/6-311++G(2d,2p) level give a structure with rotational constants that are in reasonable agreement with those of the normal isotopic species.

  15. Paramagnetic transition-metal carbonyls and cyanides

    International Nuclear Information System (INIS)

    Symons, M.C.R.; Bratt, S.W.; Wyatt, J.L.

    1982-01-01

    Exposure of tetra-alkylammonium salts of [Cr(CO) 5 I] - , [Mo(CO) 5 I] - , and [W(CO) 5 I] - , and dilute solutions of [Re(CO) 5 Br] and [Re(CO) 5 I] in methyltetrahydrofuran (mthf), to 60 Co γ-rays at 77 K gave electron-addition products characterized by large hyperfine coupling to the halogen and metal nuclei. Orbital populations for the extra electrons estimated therefrom showed trends characteristic of antibonding electrons, and in all cases the extra electron appears to be accommodated in the metal-halogen σ* orbital comprising primarily (dsub(Z 2 )-psub(z)). For the tungsten complex, a species exhibiting additional hyperfine coupling to a single proton was also detected. A species previously assigned the formula [Cr(CO) 5 I] was prepared, but gave no detectable e.s.r. spectrum. (author)

  16. Phenolic carbonyls undergo rapid aqueous photodegradation to form low-volatility, light-absorbing products

    Science.gov (United States)

    Smith, Jeremy D.; Kinney, Haley; Anastasio, Cort

    2016-02-01

    We investigated the aqueous photochemistry of six phenolic carbonyls - vanillin, acetovanillone, guaiacyl acetone, syringaldehyde, acetosyringone, and coniferyl aldehyde - that are emitted from wood combustion. The phenolic carbonyls absorb significant amounts of solar radiation and decay rapidly via direct photodegradation, with lifetimes (τ) of 13-140 min under Davis, CA winter solstice sunlight at midday (solar zenith angle = 62°). The one exception is guaiacyl acetone, where the carbonyl group is not directly connected to the aromatic ring: This species absorbs very little sunlight and undergoes direct photodegradation very slowly (τ > 103 min). We also found that the triplet excited states (3C*) of the phenolic carbonyls rapidly oxidize syringol (a methoxyphenol without a carbonyl group), on timescales of 1-5 h for solutions containing 5 μM phenolic carbonyl. The direct photodegradation of the phenolic carbonyls, and the oxidation of syringol by 3C*, both efficiently produce low volatility products, with SOA mass yields ranging from 80 to 140%. Contrary to most aliphatic carbonyls, under typical fog conditions we find that the primary sink for the aromatic phenolic carbonyls is direct photodegradation in the aqueous phase. In areas of significant wood combustion, phenolic carbonyls appear to be small but significant sources of aqueous SOA: over the course of a few hours, nearly all of the phenolic carbonyls will be converted to SOA via direct photodegradation, enhancing the POA mass from wood combustion by approximately 3-5%.

  17. Structural insights into the neuroprotective-acting carbonyl reductase Sniffer of Drosophila melanogaster.

    Science.gov (United States)

    Sgraja, Tanja; Ulschmid, Julia; Becker, Katja; Schneuwly, Stephan; Klebe, Gerhard; Reuter, Klaus; Heine, Andreas

    2004-10-01

    In vivo studies with the fruit-fly Drosophila melanogaster have shown that the Sniffer protein prevents age-dependent and oxidative stress-induced neurodegenerative processes. Sniffer is a NADPH-dependent carbonyl reductase belonging to the enzyme family of short-chain dehydrogenases/reductases (SDRs). The crystal structure of the homodimeric Sniffer protein from Drosophila melanogaster in complex with NADP+ has been determined by multiple-wavelength anomalous dispersion and refined to a resolution of 1.75 A. The observed fold represents a typical dinucleotide-binding domain as detected for other SDRs. With respect to the cofactor-binding site and the region referred to as substrate-binding loop, the Sniffer protein shows a striking similarity to the porcine carbonyl reductase (PTCR). This loop, in both Sniffer and PTCR, is substantially shortened compared to other SDRs. In most enzymes of the SDR family this loop adopts a well-defined conformation only after substrate binding and remains disordered in the absence of any bound ligands or even if only the dinucleotide cofactor is bound. In the structure of the Sniffer protein, however, the conformation of this loop is well defined, although no substrate is present. Molecular modeling studies provide an idea of how binding of substrate molecules to Sniffer could possibly occur.

  18. Measurements of carbonyls in a 13-story building.

    Science.gov (United States)

    Báez, Armando P; Padilla, Hugo G; García, Rocío M; Belmont, Raúl D; Torres, Maria del Carmen B

    2004-01-01

    Formaldehyde and acetaldehyde are emitted by many mobile and stationary sources and secondary aldehydes are intermediates in the photo-oxidation of organic compounds in the atmosphere. These aldehydes are emitted indoors by many materials such as furniture, carpets, heating and cooling systems, an by smoking. Carbonyls, mainly formaldehyde and acetaldehyde, have been studied because of their adverse health effects. In addition, formaldehyde is a suspected carcinogen. Therefore, the concentrations of formaldehyde and acetaldehyde were determined to assess the inhalation exposure doses to carbonyls for people who work in a 13-story building and in order to evaluate the cancer hazard. Carbonyl compounds in indoor and outdoor air were measured at a 13-story building located in Mexico City. The mezzanine, fifth and tenth floors, and the third level-parking garage were selected for sampling. Samples were collected in two sampling periods, the first from April 20 to 29, 1998 and the second from December 1 to 20, 1998. Carbonyls were sampled by means of DNHP-coated cartridges at a flow rate of 1 l min(-1) from 9:00 to 19:00 hours, during 2-hour time intervals and analyzed by HPLC with hours, during 2-hour time intervals and analyzed by HPLC with UV/VIS detection. Mean carbonyl concentrations were highest in the 3rd level-parking garage, with the formaldehyde concentration being the highest ranging from 108 to 418 microg m(-3). In working areas, the highest carbonyl arithmetic mean concentrations (AM) were observed on the 5th floor. Acetone and formaldehyde concentrations were highest in April ranging from 161 to 348 microg m(-3) (AM = 226) and from 157 to 270 microg m(-3) (AM = 221), respectively. Propionaldehyde and butyraldehyde were present in smaller concentrations ranging from 2 to 25 and 1 to 28 microg m(-3), respectively, considering all the samples. Mean indoor/outdoor ratios of carbonyls ranged from 1.8 to 9.6. A reduction of inhalation exposure doses of 41% and

  19. Anchoring selenido-carbonyl ruthenium clusters to functionalized silica xerogels

    International Nuclear Information System (INIS)

    Cauzzi, Daniele; Graiff, Claudia; Pattacini, Roberto; Predieri, Giovanni; Tiripicchio, Antonio

    2003-01-01

    Silica Xerogels containing carbonyl Ru 3 Se 2 nido clusters were prepared in three different ways. The simple dispersion of [Ru 3 (μ 3 -Se) 2 (CO) 7 (PPh 3 ) 2 ] via sol gel process produces an inhomogeneous material; by contrast, homogeneous xerogels were obtained by reaction of [Ru 3 (μ 3 -Se) 2 (CO) 8 (PPh 3 )] with functionalized xerogels containing grafted diphenylphosphine moieties and by reaction of [Ru 3 (CO) 12 ] with a xerogel containing grafted phosphine-selenide groups. The reaction between [Ru 3 (CO) 12 ] and dodecyl diphenylphosphine selenide led to the formation of four selenido carbonyl clusters, which are soluble in hydrocarbon solvents and can be deposited as thin films from their solution by slow evaporation. (author)

  20. Reactions of α-phosphorylated carbonyl compounds with amino alcohols

    International Nuclear Information System (INIS)

    Moskva, V.V.; Sitdikova, T.Sh.; Zykova, T.V.; Alparova, M.V.; Shagvaleev, F.Sh.

    1986-01-01

    2-Aminoethanol reacts with carbonyl compounds with the formation, depending on the structure of the latter, either of a mixture of azomethines and oxazolidines, or of only azomethines. In the development of investigations on the reactivity of α-phosphorylated carbonyl compounds the authors studied the reactions of a number of amino alcohols with phosphorylated acetaldehyde and acetone. In both cases they observed the formation of compounds of enamine structure, oxazolidines and azomethines were not observed. By means of NMR spectroscopy they established clearly the formation of the E-isomeric products. The 1 H, 31 P, and 13 C NMR spectra were recorded on a WP-80 spectrometer. Chemical shifts of protons and 13 C nuclei are given relative to TMS, and phosphorus nuclei relative to orthophosphoric acid

  1. Synthetic and mechanistic aspects of titanium-mediated carbonyl olefinations

    Energy Technology Data Exchange (ETDEWEB)

    Petasis, N.A.; Staszewski, J.P.; Hu, Yong-Han; Lu, Shao-Po [Univ. of Southern California, Los Angeles, CA (United States)

    1995-12-31

    A new method for the olefination of carbonyl compounds with dimethyl titanocene, and other related bishydrocarbyl titanocene derivatives has been recently developed in the author`s laboratories. This process is experimentally convenient and works with various types of carbonyl compounds, including aldehydes, ketones, esters, lactones, carbonates, anhydrides, amides, imides, lactams, thioesters, selenoesters, and acylsilanes. More recent studies have focused on the scope and utility of this reaction, including mechanistic studies and synthetic applications. In addition to varying the reaction conditions, the authors have examined several mixed titanocene derivatives and have found ways for carrying out this type of olefination at room temperature, such as the use of tris(trimethylsilyl) titanacyclobutene. The authors have also employed this reaction in the modification of carbohydrates and cyclobutenediones. This olefination was also followed-up with subsequent transformations to produce carbocycles and heterocycles, including tetrahydrofurans and tetrahydropyrans.

  2. A three-membered ring approach to carbonyl olefination.

    Science.gov (United States)

    Niyomchon, Supaporn; Oppedisano, Alberto; Aillard, Paul; Maulide, Nuno

    2017-10-23

    The carbon-carbon double bond, with its diverse and multifaceted reactivity, occupies a prominent position in organic synthesis. Although a variety of simple alkenes are readily available, the mild and chemoselective introduction of a unit of unsaturation into a functionalized organic molecule remains an ongoing area of research, and the olefination of carbonyl compounds is a cornerstone of such approaches. Here we show the direct olefination of hydrazones via the intermediacy of three-membered ring species generated by addition of sulfoxonium ylides, departing from the general dogma of alkenes synthesis from carbonyls. Moreover, the mild reaction conditions and operational simplicity of the transformation render the methodology appealing from a practical point of view.

  3. Emissions of Toxic Carbonyls in an Electronic Cigarette

    Directory of Open Access Journals (Sweden)

    Guthery William

    2016-01-01

    Full Text Available Electronic cigarettes (e-cigs provide a smoke-free alternative for inhalation of nicotine without the vast array of toxic and carcinogenic combustion products produced by tobacco smoke. Elevated levels of toxic carbonyls may be generated during vaporisation; however, it is unclear whether that is indicative of a fault with the device or is due to the applied conditions of the test. A device, designed and built at this facility, was tested to determine the levels of selected toxic carbonyls. The reservoir was filled with approximately 960 mg of an e-liquid formulation containing 1.8% (w/v nicotine. Devices were puffed 200 times in blocks of 40 using a standardised regime consisting of a 55 mL puff volume; 3 s puff duration; 30 s puff interval; square wave puff profile. Confirmatory testing for nicotine and total aerosol delivery resulted in mean (n = 8 values of 10 mg (RSD 12.3% and 716 mg (RSD 11.2%, respectively. Emissions of toxic carbonyls were highly variable yet were between < 0.1% and 22.9% of expected levels from a Kentucky Reference Cigarette (K3R4F puffed 200 times under Health Canada Intense smoking conditions. It has been shown that a device built to a high specification with relatively consistent nicotine and aerosol delivery emits inconsistent levels of carbonyls. The exposure is greatly reduced when compared with lit tobacco products. However, it was observed that as the reservoirs neared depletion then emission levels were significantly higher

  4. Nucleophilic tetrafluoroethylation of carbonyl compounds with fluorinated sulfones

    Czech Academy of Sciences Publication Activity Database

    Václavík, Jiří; Chernykh, Yana; Jurásek, Bronislav; Beier, Petr

    2015-01-01

    Roč. 169, Jan (2015), s. 24-31 ISSN 0022-1139 R&D Projects: GA ČR GAP207/11/0421 Grant - others:GA MŠk(CZ) ED3.2.00/08.0144; GA MŠk(CZ) LM2010005 Institutional support: RVO:61388963 Keywords : fluorine * tetrafluoroethylation * sulfones * nucleophilic addition * carbonyl compounds Subject RIV: CC - Organic Chemistry Impact factor: 2.213, year: 2015

  5. Magnetophoretic manipulation in microsystem using carbonyl iron-polydimethylsiloxane microstructures

    OpenAIRE

    Faivre, Magalie; Gelszinnis, Renaud; Degouttes, Jérôme; Terrier, Nicolas; Rivière, Charlotte; Ferrigno, Rosaria; Deman, Anne-Laure

    2014-01-01

    This paper reports the use of a recent composite material, noted hereafter i-PDMS, made of carbonyl iron microparticles mixed in a PolyDiMethylSiloxane (PDMS) matrix, for magnetophoretic functions such as capture and separation of magnetic species. We demonstrated that this composite which combine the advantages of both components, can locally generate high gradients of magnetic field when placed between two permanent magnets. After evaluating the magnetic susceptibility of the material as a ...

  6. Synthesis and characterization of poly(phenylacetylene)s with Ru(II) bis-terpyridine complexes in the side-chain.

    Science.gov (United States)

    Breul, Alexander M; Kübel, Joachim; Häupler, Bernhard; Friebe, Christian; Hager, Martin D; Winter, Andreas; Dietzek, Benjamin; Schubert, Ulrich S

    2014-04-01

    An alkyne-functionalized ruthenium(II) bis-terpyridine complex is directly copolymerized with phenylacetylene by alkyne polymerization. The polymer is characterized by size-exclusion chromatography (SEC), (1) H NMR spectroscopy, cyclic voltammetry (CV) measurements, and thermal analysis. The photophysical properties of the polymer are studied by UV-vis absorption spectroscopy. In addition, spectro-electrochemical measurements are carried out. Time-resolved luminescence lifetime decay curves show an enhanced lifetime of the metal complex attached to the conjugated polymer backbone compared with the Ru(tpy)2 (2+) model complex. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Complexes and aggregates of chlorophylls

    NARCIS (Netherlands)

    Kooyman, R.P.H.

    1980-01-01

    Chlorophyll (Chl) molecules can form complexes in two important ways: by ligation at the magnesium atom and/or by hydrogen bonding at the keto- carbonyl group. Under certain conditions these processes may give rise to dimer formation. This thesis describes some properties of complexes and dimers of

  8. Carbonyl compounds in gas and particle phases of mainstream cigarette smoke

    Energy Technology Data Exchange (ETDEWEB)

    Pang, Xiaobing, E-mail: pangxbyuanj@gmail.com [Department of Chemistry, University of York, Heslington, York, YO10 5DD (United Kingdom); Lewis, Alastair C., E-mail: ally.lewis@york.ac.uk [National Centre for Atmospheric Science, University of York, Heslington, York, YO10 5DD (United Kingdom)

    2011-11-01

    Carbonyl compounds (carbonyls) are important constituents of cigarette smoke and some are toxic and may be carcinogenic or mutagenic to humans. In this study carbonyl emissions in the gas and particle phases of mainstream cigarette smoke were assessed by GC-MS with pentafluorophenyl hydrazine (PFPH) derivatization. Seven brands of cigarettes and one brand of cigar common in the UK market and having differing nicotine, tar and carbon monoxide yields were investigated. Sixteen carbonyl components were identified in gaseous emissions and twenty in the particle phase. In the gaseous emissions, acetaldehyde presented as the predominant species, followed by formaldehyde, 2-propenal, and pentanal. In the particulate emissions, 1-hydroxy-2-propanone was the most abundant followed by formaldehyde, benzaldehyde, and 2,5-dimethylbenzaldehyde. Significant differences were found in carbonyl emissions among the brands of cigarettes. The gaseous carbonyl emissions varied in the range of 216-405 {mu}g cigarette{sup -1} ({mu}g cig{sup -1}) and the particulate carbonyl emissions varied in the range of 23-127 {mu}g cig{sup -1}. Positive correlations were found between the total emission of carbonyls, tar yield and carbon monoxide yield. Similar gas/particle (G/P) partitioning ratios of carbonyls were found among all cigarettes, which implies that G/P partitions of carbonyls in smoke mainly depend on the physical properties of the carbonyls. The gaseous carbonyl emissions were enhanced by 40% to 130% when some of the water, accounting for 8-12% of cigarettes in mass, was removed from the tobacco. Non-filtered cigarettes showed significantly higher carbonyl emissions compared to their filtered equivalents. Carbonyl particulate accounted for 11-19% by mass of total particulate matter from tobacco smoke. The cigar generated 806 {mu}g cig{sup -1} gaseous and 141 {mu}g cig{sup -1} particulate carbonyls, which is 2-4 times greater than the cigarettes. - Highlights: {yields} Carbonyl

  9. Carbonyl compounds in gas and particle phases of mainstream cigarette smoke

    International Nuclear Information System (INIS)

    Pang, Xiaobing; Lewis, Alastair C.

    2011-01-01

    Carbonyl compounds (carbonyls) are important constituents of cigarette smoke and some are toxic and may be carcinogenic or mutagenic to humans. In this study carbonyl emissions in the gas and particle phases of mainstream cigarette smoke were assessed by GC-MS with pentafluorophenyl hydrazine (PFPH) derivatization. Seven brands of cigarettes and one brand of cigar common in the UK market and having differing nicotine, tar and carbon monoxide yields were investigated. Sixteen carbonyl components were identified in gaseous emissions and twenty in the particle phase. In the gaseous emissions, acetaldehyde presented as the predominant species, followed by formaldehyde, 2-propenal, and pentanal. In the particulate emissions, 1-hydroxy-2-propanone was the most abundant followed by formaldehyde, benzaldehyde, and 2,5-dimethylbenzaldehyde. Significant differences were found in carbonyl emissions among the brands of cigarettes. The gaseous carbonyl emissions varied in the range of 216-405 μg cigarette -1 (μg cig -1 ) and the particulate carbonyl emissions varied in the range of 23-127 μg cig -1 . Positive correlations were found between the total emission of carbonyls, tar yield and carbon monoxide yield. Similar gas/particle (G/P) partitioning ratios of carbonyls were found among all cigarettes, which implies that G/P partitions of carbonyls in smoke mainly depend on the physical properties of the carbonyls. The gaseous carbonyl emissions were enhanced by 40% to 130% when some of the water, accounting for 8-12% of cigarettes in mass, was removed from the tobacco. Non-filtered cigarettes showed significantly higher carbonyl emissions compared to their filtered equivalents. Carbonyl particulate accounted for 11-19% by mass of total particulate matter from tobacco smoke. The cigar generated 806 μg cig -1 gaseous and 141 μg cig -1 particulate carbonyls, which is 2-4 times greater than the cigarettes. - Highlights: → Carbonyl emission factors in both gas (16 species) and

  10. Synthesis and Characterization of a Heteroleptic Ru(II Complex of Phenanthroline Containing Oligo-Anthracenyl Carboxylic Acid Moieties

    Directory of Open Access Journals (Sweden)

    Peter A. Ajibade

    2010-09-01

    Full Text Available In an effort to develop new ruthenium(II complexes, this work describes the design, synthesis and characterization of a ruthenium(II functionalized phenanthroline complex with extended π-conjugation. The ligand were L1 (4,7-bis(2,3-dimethylacrylic acid-1,10-phenanthroline, synthesized by a direct aromatic substitution reaction, and L2 (4,7-bis(trianthracenyl-2,3-dimethylacrylic acid-1,10-phenanthroline, which was synthesized by the dehalogenation of halogenated aromatic compounds using a zero-valent palladium cross-catalyzed reaction in the absence of magnesium-diene complexes and/or cyclooctadienyl nickel (0 catalysts to generate a new carbon-carbon bond (C-C bond polymerized hydrocarbon units. The ruthenium complex [RuL1L2(NCS2] showed improved photophysical properties (red-shifted metal-to-ligand charge-transfer transition absorptions and enhanced molar extinction coefficients, luminescence and interesting electrochemical properties. Cyclic and square wave voltammetry revealed five major redox processes. The number of electron(s transferred by the ruthenium complex was determined by chronocoulometry in each case. The results show that processes I, II and III are multi-electron transfer reactions while processes IV and V involved one-electron transfer reaction. The photophysical property of the complex makes it a promising candidate in the design of chemosensors and photosensitizers, while its redox-active nature makes the complex a potential mediator of electron transfer in photochemical processes.

  11. Ambient levels of carbonyl compounds and their sources in Guangzhou, China

    Science.gov (United States)

    Feng, Yanli; Wen, Sheng; Chen, Yingjun; Wang, Xinming; Lü, Huixiong; Bi, Xinhui; Sheng, Guoying; Fu, Jiamo

    Ambient levels of carbonyl compounds and their possible sources, vehicular exhaust and cooking exhaust, were studied at seven places in Guangzhou, including five districts (a residential area, an industrial area, a botanical garden, a downtown area and a semi-rural area), a bus station and a restaurant during the period of June-September 2003. Nineteen carbonyl compounds were identified in the ambient air, of which acetone was the most abundant carbonyl, followed by formaldehyde and acetaldehyde. Only little changes were found in carbonyl concentration levels in the five different districts because of their dispersion and mixture in the atmosphere in summer. The lower correlations between the carbonyls' concentrations might result from the mixture of carbonyls derived from different sources, including strong photochemical reactions at noon in summer. Formaldehyde and acetaldehyde were the main carbonyls in bus station, while straight-chain carbonyls were comparatively abundant in cooking exhaust. Besides vehicular exhaust, cooking might be another major source of carbonyl compounds in Guangzhou City, especially for high molecular weight carbonyls.

  12. A method of detecting carbonyl compounds in tree leaves in China.

    Science.gov (United States)

    Huang, Juan; Feng, Yanli; Fu, Jiamo; Sheng, Guoying

    2010-06-01

    Carbonyl compounds have been paid more and more attention because some carbonyl species have been proven to be carcinogenic or a risk for human health. Plant leaves are both an important emission source and an important sink of carbonyl compounds. But the research on carbonyl compounds from plant leaves is very scarce. In order to make an approach to the emission mechanism of plant leaves, a new method was established to extract carbonyl compounds from fresh plant leaves. The procedure combining derivatization with ultrasonication was developed for the fast extraction of carbonyl compounds from tree leaves. Fresh leaves (Metasequoia glyptostroboides), were selected and extracted by this method. Seven carbonyl compounds, including formaldehyde, acetaldehyde, acetone, acrolein, p-tolualdehyde, m/o-tolualdehyde, and hexaldehyde were determined and quantified. The most common carbonyl species of the four tree leaves were formaldehyde, acrolein, and m/o-tolualdehyde. They accounted for 67.3% in cedar, 50.8% in sweet olive, 45.8% in dawn redwood, and 44.6% in camphor tree, respectively. Camphor tree had the highest leaf level of m/o-tolualdehyde with 15.0 +/- 3.4 microg g(-1)(fresh leaf weight), which indicated that camphor tree may be a bioindicator of the level of tolualdehyde or xylene in the atmosphere. By analyzing carbonyl compounds from different tree leaves, it is not only helpful for further studying the relationship between sink and emission of carbonyls from plants, but also helpful for exploring optimum plant population in urban greening.

  13. Determination of Carbonyl Functional Groups in Bio-oils by Potentiometric Titration: The Faix Method.

    Science.gov (United States)

    Black, Stuart; Ferrell, Jack R

    2017-02-07

    Carbonyl compounds present in bio-oils are known to be responsible for bio-oil property changes upon storage and during upgrading. Specifically, carbonyls cause an increase in viscosity (often referred to as 'aging') during storage of bio-oils. As such, carbonyl content has previously been used as a method of tracking bio-oil aging and condensation reactions with less variability than viscosity measurements. Additionally, carbonyls are also responsible for coke formation in bio-oil upgrading processes. Given the importance of carbonyls in bio-oils, accurate analytical methods for their quantification are very important for the bio-oil community. Potentiometric titration methods based on carbonyl oximation have long been used for the determination of carbonyl content in pyrolysis bio-oils. Here, we present a modification of the traditional carbonyl oximation procedures that results in less reaction time, smaller sample size, higher precision, and more accurate carbonyl determinations. While traditional carbonyl oximation methods occur at room temperature, the Faix method presented here occurs at an elevated temperature of 80 °C.

  14. A Moessbauer effect study of the bonding in several organoiron carbonyl clusters

    International Nuclear Information System (INIS)

    Long, G.J.; O'Brien, J.F.

    1988-01-01

    After a brief review of the applications of the Moessbauer effect to cyclopentadienyl containing compounds, the chemistry and spectral properties of the various iron carbonyl complexes are described. The electronic properties of a series of trinuclear and tetranuclear organoiron clusters have been investigated through Fenske-Hall self-consistent field molecular orbital calculations, and the results are compared with the Moessbauer effect isomer shifts. A linear correlation is found between the Slater effective nuclear charge, as calculated from the Fenske-Hall partial orbital occupancy factors, and the isomer shift. In these compounds the 4s orbital populations are rather constant. However, the cis and trans isomers of [CpFe(CO) 2 ] 2 have a significantly lower 4s orbital populations. In this case, the reduced 4s population must be accounted for by adding it to the effective nuclear charge to obtain a good correlation with the isomer shift. (orig.)

  15. Electromagnetic and Microwave Absorption Properties of Carbonyl Tetrapod-Shaped Zno Nanostructures Composite Coatings

    Science.gov (United States)

    Yu, Haibo; Qin, Hui; Huang, Yunhua

    2012-08-01

    CIP/T-ZnO/EP composite coatings with carbonyl iron powders (CIP) and tetrapodshaped ZnO (T-ZnO) nanostructures as absorbers, and epoxy resin (EP) as matrix were prepared. The complex permittivity, permeability and microwave absorption properties of the coatings were investigated in the frequency range of 2-18 GHz. The effects of the weight ratio (CIP/T-ZnO/EP), the thickness and the solidification temperature on microwave absorption properties were discussed. When the weight ratio (CIP/TZnO/ EP), the thickness and the solidification temperature is 28:2:22, 1.8 mm, and 10°C, respectively, the optimal wave absorption with the minimum reflection loss (RL) value of -22.38 dB at 15.67 GHz and the bandwidth (RLcoatings may have a promising application in Ku-band (12-18 GHz).

  16. Carbonyl Compounds Produced by Vaporizing Cannabis Oil Thinning Agents.

    Science.gov (United States)

    Troutt, William D; DiDonato, Matthew D

    2017-11-01

    Cannabis use has increased in the United States, particularly the use of vaporized cannabis oil, which is often mixed with thinning agents for use in vaporizing devices. E-cigarette research shows that heated thinning agents produce potentially harmful carbonyls; however, similar studies have not been conducted (1) with agents that are commonly used in the cannabis industry and (2) at temperatures that are appropriate for cannabis oil vaporization. The goal of this study was to determine whether thinning agents used in the cannabis industry produce potentially harmful carbonyls when heated to a temperature that is appropriate for cannabis oil vaporization. Four thinning agents (propylene glycol [PG], vegetable glycerin [VG], polyethylene glycol 400 [PEG 400], and medium chain triglycerides [MCT]) were heated to 230°C and the resulting vapors were tested for acetaldehyde, acrolein, and formaldehyde. Each agent was tested three times. Testing was conducted in a smoking laboratory. Carbonyl levels were measured in micrograms per puff block. Analyses showed that PEG 400 produced significantly higher levels of acetaldehyde and formaldehyde than PG, MCT, and VG. Formaldehyde production was also significantly greater in PG compared with MCT and VG. Acrolein production did not differ significantly across the agents. PG and PEG 400 produced high levels of acetaldehyde and formaldehyde when heated to 230°C. Formaldehyde production from PEG 400 isolate was particularly high, with one inhalation accounting for 1.12% of the daily exposure limit, nearly the same exposure as smoking one cigarette. Because PG and PEG 400 are often mixed with cannabis oil, individuals who vaporize cannabis oil products may risk exposure to harmful formaldehyde levels. Although more research is needed, consumers and policy makers should consider these potential health effects before use and when drafting cannabis-related legislation.

  17. Determination of Carbonyl Compounds in Cigarette Mainstream Smoke. The CORESTA 2010 Collaborative Study and Recommended Method

    Directory of Open Access Journals (Sweden)

    Intorp M

    2014-12-01

    Full Text Available A recommended method has been developed and published by CORESTA, applicable to the quantification of selected carbonyl compounds (acetaldehyde, formaldehyde, acetone, acrolein, methyl ethyl ketone, crotonaldehyde, propionaldehyde and butyraldehyde in cigarette mainstream smoke. The method involved smoke collection in impinger traps, derivatisation of carbonyls with 2,4-dinitrophenylhydrazine (DNPH, separation of carbonyl hydrazones by reversed phase high performance liquid chromatography and detection by ultra violet or diode array.

  18. Determination of carbonyl compounds in air by HPLC

    International Nuclear Information System (INIS)

    Garcia, S.; Perez, R.M.; Campos, A.; Gonzalez, D.

    1995-09-01

    A method for the determination of seven carbonyl compounds in air is presented. The procedure involve sampling of air by a Sep-Pak cartridge impregnated with 2,4-dinitrophenylhydrazine. Elution was done with 3 mL of acetonitrile and the eluate was diluted to 5 mL. The analysis was done by HPLC with UV detection and external standard method quantification. It has been achieved relative standard deviations about 5% and detection limits of 80 ng/cartridge for formaldehyde, acetaldehyde and acetone+acrolein. Three different types of samples (rural, urban, petrol emission) were successfully analyzed

  19. Determination of carbonyl compounds in air by HPLC

    International Nuclear Information System (INIS)

    Garcia, S.; Perez, R.M.; Campos, A.; Gonzalez, D.

    1995-01-01

    A method for the determination of seven carbonyl compounds in air is presented. The procedure involve sampling of air by a Sep-Pak Cartridge impregnated with 2,4-dinitrophenylhydrazine. Elution was done with 3 mL of acetonitrile and the eluate was diluted to 5 mL. The analysis was done by HPLC with UV detection and external standard method quantification. It has been achieved relative standard deviations about 5% and detection limits of 80 ng/cartridge for formaldehyde, acetaldehyde and acetoacetonitrile. Three different types of samples (rural, urban, petrol emission) were successfully analyzed. (Author) 12 refs

  20. Magnetic properties of carbonyl iron particles in magnetorheological fluids

    International Nuclear Information System (INIS)

    Gorodkin, S R; James, R O; Kordonski, W I

    2009-01-01

    Knowledge of the magnetic properties of dispersed magnetic particles is a prerequisite to the design an MR fluid with desired performance. A term specific susceptibility is introduced for characterization of particle susceptibility. The study was performed with the Bartington MS2B magnetic susceptibility system on small samples volume. Specific magnetic susceptibility of iron particles was found to be a linear function of median particle size. Structural change in the fluid, including particle organization, led to susceptibility drift and may affect fluid performance. It was shown that susceptibility data can be used for evaluation of the concentration of carbonyl iron particles in MR fluids.

  1. A biotin enrichment strategy identifies novel carbonylated amino acids in proteins from human plasma

    DEFF Research Database (Denmark)

    Havelund, Jesper F; Wojdyla, Katarzyna; Davies, Michael J

    2017-01-01

    Protein carbonylation is an irreversible protein oxidation correlated with oxidative stress, various diseases and ageing. Here we describe a peptide-centric approach for identification and characterisation of up to 14 different types of carbonylated amino acids in proteins. The modified residues...... in vitro metal ion-catalysed oxidation. Furthermore, we assigned 133 carbonylated sites in 36 proteins in native human plasma protein samples. The optimised workflow enabled detection of 10 hitherto undetected types of carbonylated amino acids in proteins: aldehyde and ketone modifications of leucine...

  2. Carbonyl[4-(2,3-dimethylphenylaminopent-3-en-2-onato-κ2N,O](triphenylphosphine-κPrhodium(I

    Directory of Open Access Journals (Sweden)

    Gertruida J. S. Venter

    2009-11-01

    Full Text Available In the title compound, [Rh(C13H16NO(C18H15P(CO], the coordination geometry of the RhI atom is square-planar, formed by the coordinating N and O atoms of the bidentate enaminoketonate ligand, one C atom from the carbonyl group and a P atom from triphenylphosphine. The complex displays a 0.591 (3:0.409 (3 ratio disorder of the phenyl unit of the monoanionic N,O-bidentate ligand. Intramolecular hydrogen bonding is observed between a C—H group of the triphenylphosphine unit and the O atom of the enaminoketonate ligand.

  3. Synthesis, structural characterization and cytotoxic activity of two new organoruthenium(II complexes

    Directory of Open Access Journals (Sweden)

    SANJA GRGURIC-SIPKA

    2008-06-01

    Full Text Available Two new p-cymene ruthenium(II complexes containing as additional ligands N-methylpiperazine ([(η6-p-cymeneRuCl2(CH3NH(CH24NH]PF6, complex 1 or vitamin K3-thiosemicarbazone ([(η6-p-cymeneRuCl2(K3tsc], complex 2 were synthesized starting from [(η6-p-cymene2RuCl2]2 and the corresponding ligand. The complexes were characterized by elemental analysis, IR, electronic absorption and NMR spectroscopy. The X-ray crystal structure determination of complex 1 revealed “piano-stool” geometry. The differences in the cytotoxic activity of the two complexes are discussed in terms of the ligand present.

  4. Thiosemicarbazone complexes of the platinum metals. A story of ...

    Indian Academy of Sciences (India)

    Unknown

    Thiosemicarbazone complexes; platinum metals; variable coordination; ... carbonylic carbon via one or two intervening atoms, D,N,S tricoordination usually takes .... modelling studies show that in this coordination mode, the phenyl ring of the.

  5. Composition of amino acid using carbon monoxide. Amide carbonylation reaction

    Energy Technology Data Exchange (ETDEWEB)

    Izawa, Kunisuke (Ajinomoto Co., Inc., Tokyo (Japan))

    1989-02-01

    Amide carbonylation reaction is a method to compose N-acyl-{alpha}-amino acid from aldehyde, carboxylic acid amide, and carbon monoxide in a phase and with high yield. Unlike the conventional Strecker reaction, this method does not use HCN which is in question on public pollution and does not require hydrolysis. This amide carbonylation reaction was discovered by Wakamatsu and others of Ajinomoto Co.,Ltd. Present application examples of this method are the composition of N-acetyl amino acid from the aldehyde class, the composition of N-Acyl amino acid from olefin, the composition of N-acyl or acetyl amino acid from the raw material of alcohol and the halide class, the composition of N-acyl or acetyl amino acid via the isomerization of epoxide and allyl alcohol, the composition of amino dicarboxylic acid, applying deoxidation of ring acid anhydride, the composition of N-acyl amino acid from the raw material of the amine class, the stereoselective composition of -substitution ring-{alpha}-amino acid, and the composition of amino aldehyde. 24 refs., 2 figs., 2 tabs.

  6. Synthesis of dimethyl carbonate by oxidative carbonylation of methanol

    Energy Technology Data Exchange (ETDEWEB)

    Lee, B.G.; Han, M.S.; Kim, H.S.; Ahn, B.S.; Park, K.Y.

    1999-07-01

    Dimethyl carbonate (DMC) synthesis reaction by oxidative carbonylation of methanol has been studied using vapor phase flow reaction system in the presence of Cu-based catalysts. A series of Cu-based catalysts were prepared by the conventional impregnation method using activated carbon (AC) as support. The effect of various promoters and reaction conditions on the catalytic reactivities was intensively evaluated in terms of methanol conversion and DMC selectivity. The morphological change of catalysts during the reaction was also compared by X-ray diffraction and SEM analysis. Regardless of catalyst compositions, the optimal reaction temperature for oxidative carbonylation of methanol was found to be around 120--130 C. The reaction rate was too slow below 100 C, while too many by-products were produced above 150 C. Among the various catalysts employed, CuCl{sub 2}/NaOH/AC catalyst with the mole ratio of OH/Cu = 0.5--1.0 has shown the best catalytic performance, which appears to have a strong relationship with the formation of intermediate species, Cu{sub 2}(OH){sub 3}Cl.

  7. Rh(I) -Catalyzed Intramolecular Carbonylative C-H/C-I Coupling of 2-Iodobiphenyls Using Furfural as a Carbonyl Source.

    Science.gov (United States)

    Furusawa, Takuma; Morimoto, Tsumoru; Nishiyama, Yasuhiro; Tanimoto, Hiroki; Kakiuchi, Kiyomi

    2016-08-19

    Synthesis of fluoren-9-ones by a Rh-catalyzed intramolecular C-H/C-I carbonylative coupling of 2-iodobiphenyls using furfural as a carbonyl source is presented. The findings indicate that the rate-determining step is not a C-H bond cleavage but, rather, the oxidative addition of the C-I bond to a Rh(I) center. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Maternal aging affects oocyte resilience to carbonyl cyanide-m-chlorophenylhydrazone -induced mitochondrial dysfunction in cows.

    Directory of Open Access Journals (Sweden)

    Kazuki Kansaku

    Full Text Available Mitochondrial quality control is important for maintaining cellular and oocyte viability. In addition, aging affects mitochondrial quality in many cell types. In the present study, we examined how aging affects oocyte mitochondrial biogenesis and degeneration in response to induced mitochondrial dysfunction. Cumulus oocyte complexes were harvested from the ovaries of young (21‒45 months and aged (≥120 months cows and treated for 2 hours with 10 μM carbonyl cyanide-m- chlorophenylhydrazone (CCCP, or a vehicle control, after which cumulus oocyte complexes were subjected to in vitro fertilization and culture. CCCP treatment reduced ATP content and increased reactive oxygen species (ROS levels in the oocytes of both young and aged cows. When CCCP-treated cumulus oocyte complexes were subsequently cultured for 19 hours and/or subjected to fertilization, high ROS levels in oocytes and a low rate of blastocyst development was observed in oocytes derived from aged cows. In addition, we observed differential responses in mitochondrial biogenesis to CCCP treatment between young and aged cows. CCCP treatment enhanced mitochondrial biogenesis concomitant with upregulation of SIRT1 expression in oocytes of young, but not aged, cows. In conclusion, aging affects mitochondrial quality control and recuperation of oocytes following CCCP-induced mitochondrial dysfunction.

  9. Preparation and microwave shielding property of silver-coated carbonyl iron powder

    International Nuclear Information System (INIS)

    Cao, Xiao Guo; Ren, Hao; Zhang, Hai Yan

    2015-01-01

    Highlights: • The silver-coated carbonyl iron powder is prepared by the electroless plating process. • The silver-coated carbonyl iron powder is a new kind of conductive filler. • The reflection and absorption dominate the shielding mechanism of the prepared powder. • Increasing the thickness of electroconductive adhesive will increase the SE. - Abstract: Electroless silver coating of carbonyl iron powder is demonstrated in the present investigation. The carbonyl iron powders are characterized by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction analysis (XRD) before and after the coating process. The relatively uniform and continuous silver coating is obtained under the given coating conditions. In this paper, the electromagnetic interference (EMI) shielding mechanism of the silver-coated carbonyl iron powder is suggested. The reflection of silver coating and absorption of carbonyl iron powder dominate the shielding mechanism of the silver-coated carbonyl iron powder. The silver-coated carbonyl iron powders are used as conductive filler in electroconductive adhesive for electromagnetic interference shielding applications. The effect of the thickness of electroconductive adhesive on the shielding effectiveness (SE) is investigated. The results indicate that the SE increases obviously with the increase of the thickness of electroconductive adhesive. The SE of the electroconductive adhesive with 0.35 mm thickness is above 38 dB across the tested frequency range

  10. Comparison of carbonyl compounds emissions from diesel engine fueled with biodiesel and diesel

    Science.gov (United States)

    He, Chao; Ge, Yunshan; Tan, Jianwei; You, Kewei; Han, Xunkun; Wang, Junfang; You, Qiuwen; Shah, Asad Naeem

    The characteristics of carbonyl compounds emissions were investigated on a direct injection, turbocharged diesel engine fueled with pure biodiesel derived from soybean oil. The gas-phase carbonyls were collected by 2,4-dinitrophenylhydrazine (DNPH)-coated silica cartridges from diluted exhaust and analyzed by HPLC with UV detector. A commercial standard mixture including 14 carbonyl compounds was used for quantitative analysis. The experimental results indicate that biodiesel-fueled engine almost has triple carbonyls emissions of diesel-fueled engine. The weighted carbonyls emission of 8-mode test cycle of biodiesel is 90.8 mg (kW h) -1 and that of diesel is 30.7 mg (kW h) -1. The formaldehyde is the most abundant compound of carbonyls for both biodiesel and diesel, taking part for 46.2% and 62.7% respectively. The next most significant compounds are acetaldehyde, acrolein and acetone for both fuels. The engine fueled with biodiesel emits a comparatively high content of propionaldehyde and methacrolein. Biodiesel, as an alternative fuel, has lower specific reactivity (SR) caused by carbonyls compared with diesel. When fueled with biodiesel, carbonyl compounds make more contribution to total hydrocarbon emission.

  11. Protein carbonyl content: a novel biomarker for aging in HIV/AIDS patients

    Directory of Open Access Journals (Sweden)

    Vaishali Kolgiri

    2017-01-01

    Conclusions: Carbonyl content may has a role as a biomarker for detecting oxidative DNA damage induced ART toxicity and/or accelerated aging in HIV/AIDS patients. Larger studies are warranted to elucidate the role of carbonyl content as a biomarker for premature aging in HIV/AIDS patients.

  12. Design and fabrication of microfluidic mixer from carbonyl iron–PDMS composite membrane

    KAUST Repository

    Li, Jiaxing; Zhang, Mengying; Wang, Limu; Li, Weihua; Sheng, Ping; Wen, Weijia

    2010-01-01

    This paper introduces a carbonyl iron-PDMS (CI-PDMS) composite magnetic elastomer in which carbonyl iron (CI) particles are uniformly distributed in a PDMS matrix. The CI particles and the PDMS were mixed at different weight ratios and tested

  13. Metal-atom fluorescence from the quenching of metastable rare gases by metal carbonyls

    International Nuclear Information System (INIS)

    Hollingsworth, W.E.

    1982-11-01

    A flowing afterglow apparatus was used to study the metal fluorescence resulting from the quenching of metastable rare-gas states by metal carbonyls. The data from the quenching or argon, neon, and helium by iron and nickel carbonyl agreed well with a restricted degree of freedom model indicating a concerted bond-breaking dissociation

  14. Protein carbonylation and metal-catalyzed protein oxidation in a cellular perspective

    DEFF Research Database (Denmark)

    Møller, Ian Max; Rogowska-Wrzesinska, Adelina; Rao, R S P

    2011-01-01

    Proteins can become oxidatively modified in many different ways, either by direct oxidation of amino acid side chains and protein backbone or indirectly by conjugation with oxidation products of polyunsaturated fatty acids and carbohydrates. While reversible oxidative modifications are thought...... to be relevant in physiological processes, irreversible oxidative modifications are known to contribute to cellular damage and disease. The most well-studied irreversible protein oxidation is carbonylation. In this work we first examine how protein carbonylation occurs via metal-catalyzed oxidation (MCO) in vivo...... and in vitro with an emphasis on cellular metal ion homeostasis and metal binding. We then review proteomic methods currently used for identifying carbonylated proteins and their sites of modification. Finally, we discuss the identified carbonylated proteins and the pattern of carbonylation sites in relation...

  15. Development of an automatic sampling device for the continuous measurement of atmospheric carbonyls compounds

    International Nuclear Information System (INIS)

    Perraud, V.

    2007-12-01

    Two sampling strategies were studied to develop an automatic instrument for the continuous measurement of atmospheric carbonyl compounds. Because of its specificity towards carbonyls compounds, sampling by using a transfer of gaseous phase in a liquid phase associated with a simultaneous chemical derivatization of the trapped compounds was first studied. However, this method do not allow a quantitative sampling of all studied carbonyl compounds, nor a continuous measurement in the field. To overcome the difficulties, a second strategy was investigated: the cryogenic adsorption onto solid adsorbent followed by thermodesorption and a direct analysis by GC/MS. Collection efficiency using different solid adsorbents was found greater than 95% for carbonyl compounds consisting of 1 to 7 carbons. This work is a successful first step towards the realization of the automatic sampling device for a continuous measurement of atmospheric carbonyls compounds. (author)

  16. Impact of HVAC filter on indoor air quality in terms of ozone removal and carbonyls generation

    Science.gov (United States)

    Lin, Chi-Chi; Chen, Hsuan-Yu

    2014-06-01

    This study aims at detecting ozone removal rates and corresponding carbonyls generated by ozone reaction with HVAC filters from various building, i.e., shopping mall, school, and office building. Studies were conducted in a small-scale environmental chamber. By examining dust properties including organic carbon proportion and specific surface area of dusts adsorbed on filters along with ozone removal rates and carbonyls generation rate, the relationship among dust properties, ozone removal rates, and carbonyls generation was identified. The results indicate a well-defined positive correlation between ozone removal efficiency and carbonyls generation on filters, as well as a positive correlation among the mass of organic carbon on filters, ozone removal efficiency and carbonyls generations.

  17. Activation of heterogenised rhodium carbonylation catalyst infrared spectroscopic study

    Energy Technology Data Exchange (ETDEWEB)

    Scurrell, M S

    1977-01-01

    In a study related to heterogeneous versions of homogeneous catalysts active in carbonylation of methanol to acetic acid, the catalyst consisted of 1Vertical Bar3< rhodium as rhodium trichloride supported on 13X zeolite and evacuated at 437/sup 0/K. Contacting the catalyst with carbon monoxide caused two bands, at 2025 and 2095 cm/sup -1/, to appear. Contact with a mixture of carbon monoxide and methyl iodide (the usual promoter) caused bands at 2085, 1710, 1440, and 1370 cm/sup -1/ to appear; the first two correspond to the bands at 2062 and 1711 cm/sup -1/ in homogeneous catalysts attributed to the formation of Rh(CH/sup 3/CO)(CO)X/sup 2/I/sup -/. Spectra.

  18. SILP catalysis in gas-phase hydroformylation and carbonylation

    Energy Technology Data Exchange (ETDEWEB)

    Riisager, A.; Fehrmann, R. [Technical Univ. of Denmark, Lyngby (Denmark). Dept. of Chemistry; Haumann, M.; Wasserscheid, P. [Univ. Erlangen-Nuernberg (Germany). Lehrstuhl fuer Chemische Reaktionstechnik

    2006-07-01

    Supported ionic liquid phase (SILP) catalysts are new materials consisting of an ionic liquid-metal catalyst solution highly dispersed on a porous support. The use of a non-volatile, ionic liquid catalyst phase in SILP catalysts results in a stable heterogeneous-type material with selectivity and efficiency like homogeneous catalysts. The silica-supported SILP Rh-bisphosphine hydroformylation catalyst exhibited good activities and excellent selectivities in gas phase hydroformylation with stability exceeding 700 hours time-on-stream. Spectroscopic and kinetic data confirmed the homogeneous nature of the catalyst. In the Rh- SILP catalysed carbonylation of methanol the formation of undesired by-products could be suppressed by variation of residence time and gas pressure. (orig.)

  19. Determination of bond energies by mass spectrometry. Some transition metal carbonyls

    International Nuclear Information System (INIS)

    Michels, G.D.

    1979-01-01

    Two groups of transition metal carbonyls have been studied, M(CO) 6 and M(CO) 5 CS complexes of the Group VIB metals and M 2 (CO) 10 complexes of the Group VIIB metals. Results for the hexacarbonyl complexes indicate that the measured fragmentation energies are in error by 0.25 +- 0.02 eV per CO produced. This is attributed to excitation of CO to the first vibrational state. Least-squares dissociation energies calculated from corrected data for M(CO) 5 CS complexes indicate that the M--CS bond is 3 to 4 times stronger than the M--CO bonds. Substitution of CS for CO in going from M(CO) 6 to M(CO) 5 CS weakens the remaining M--CO bonds by an average of 0.2 eV. Previously unreported MnTc(CO) 10 and TcRe(CO) 10 are prepared by halide substitution of Tc(CO) 5 Br and Re(CO) 5 Br with Mn(CO) 5 - and Tc(CO) 5 - , respectively. In the positive ion, metal and mixed-metal decacarbonyls are considered as (CO) 5 M + --M(CO) 5 complexes possessing five strong and five weak M--CO bonds. For Mn 2 (CO) 10 and Re 2 (CO) 10 , M + --M dissociation energies are 3.0 +- 0.1 and 4.0 +- 0.3 eV, respectively. These energies are 2.5 times greater than those reported for homolytic cleavage to M(CO) 5 + and M(CO) 5

  20. Dimers of fluorinated methanes with carbonyl sulfide: the rotational spectrum and structure of difluoromethane-OCS.

    Science.gov (United States)

    Serafin, Michal M; Peebles, Sean A

    2008-12-11

    The pure rotational spectra of four isotopologues of the difluoromethane-carbonyl sulfide dimer have been measured in the 5-15 GHz region with use of pulsed-nozzle Fourier-transform microwave spectroscopy. The complex was determined to possess an ab plane of symmetry with a center of mass separation of 3.41(2) A and dipole moment components mu(a) = 1.1386(18) D, mu(b) = 0.4840(63) D, mu(total) = 1.2372(41) D. Experimental planar moments indicate that the two fluorine atoms straddle the symmetry plane while one of the C-H bonds of the difluoromethane monomer is aligned to interact with the oxygen atom of the OCS molecule. The assignment of the rotational spectrum for this dimer completes the experimental studies of the series of dimers involving fluorinated methanes (HCF(3), H(2)CF(2), and H(3)CF) complexed with OCS and makes possible a comparison of properties within this series.

  1. Molecular complexes of tungsten oxotetrachloride with azomethins

    International Nuclear Information System (INIS)

    Abramenko, Yu.V.; Garnovskij, A.D.; Abramenko, V.A.; Medvedeva, T.E.

    1992-01-01

    Series of new molecular complexes of tungsten oxotetrachloride with benza- and salicylalimines of equimolar compositions obtained. Substances are studied using element analysis, IR spectroscopy and conductometry. Octahedral structure of complexes with central atom coordination of benzalaniline molecules via azomethin nitrogen atom, and salicylalimines - via carbonyl oxygen atom of quinoid tantometric form of ligand is assumed

  2. Two Discrete RuCp* (Cp*=Pentamethylcyclopentadienyl) Binding Modes of N-Confused Porphyrins: Peripheral π Complex and Sitting Atop Ruthenocenophane Complex by Skeletal Transformation.

    Science.gov (United States)

    Yamamoto, Takaaki; Mitsuno, Koki; Mori, Shigeki; Itoyama, Shuhei; Shiota, Yoshihito; Yoshizawa, Kazunari; Ishida, Masatoshi; Furuta, Hiroyuki

    2018-05-07

    Complexation of a RuCp* cation with N-confused tetraarylporphyrins (NCPs) forms directly bound ruthenium(II) pentamethylcyclopentadienyl (Cp*) π-complex on a specific meso-aryl group (e.g., phenyl) neighboring peripheral imino nitrogen of NCPs in high yields. In contrast, in the case of NCPs bearing bulky meso-substituents (e.g., 3,5-di-tert-butylphenyl), new ruthenocenophane-like complex embedded on an N-confused calix[4]phyrin was formed through multiple C-H bond activation of methyl groups of Cp* ligand. The mechanistic insight into the formation of the ruthenocenophane was derived from DFT calculations. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Active control of methanol carbonylation selectivity over Au/carbon anode by electrochemical potential.

    Science.gov (United States)

    Funakawa, Akiyasu; Yamanaka, Ichiro; Otsuka, Kiyoshi

    2005-05-12

    Electrochemical oxidative carbonylation of methanol was studied over Au supported carbon anode in CO. The major carbonylation products were dimethyl oxalate (DMO) and dimethyl carbonate (DMC). The minor oxidation products were dimethoxy methane (DMM) and methyl formate (MF) from methanol and CO(2). Influences of various reaction conditions were studied on carbonylation activities and selectivities. The selectivities to DMO and DMC can be controlled by the electrochemical potential. Electrocatalysis of Au/carbon anode was studied by cyclic voltammetry (CV), stoichiometric reactions among Au(3+), methanol, and CO, and UV-vis spectra. The Au/carbon anode was characterized by XRD, SEM, and BE images before and after the carbonylation. These experimental facts strongly suggest that transition of oxidation states of Au affects changing of the carbonylation selectivities to DMO and DMC. Au(0) is the active species for the selective DMO formation by direct electrochemical carbonylation at low potentials (selective DMC formation by indirect electrochemical carbonylation through Au(3+)/Au(+) redox at high potentials (>+1.3 V).

  4. Protein carbonylation sites in bovine raw milk and processed milk products.

    Science.gov (United States)

    Milkovska-Stamenova, Sanja; Mnatsakanyan, Ruzanna; Hoffmann, Ralf

    2017-08-15

    During thermal treatment of milk, proteins are oxidized, which may reduce the nutritional value of milk, abolish protein functions supporting human health, especially important for newborns, and yield potentially harmful products. The side chains of several amino acids can be oxidized to reactive carbonyls, which are often used to monitor oxidative stress in organisms. Here we mapped protein carbonylation sites in raw milk and different brands of pasteurized, ultra high temperature (UHT) treated milk, and infant formulas (IFs) after digesting the precipitated proteins with trypsin. Reactive carbonyls were derivatized with O-(biotinylcarbazoylmethyl)hydroxylamine to enrich the modified peptides by avidin-biotin affinity chromatography and analyze them by nanoRP-UPLC-ESI-MS. Overall, 53 unique carbonylated peptides (37 carbonylation sites, 15 proteins) were identified. Most carbonyls were derived from dicarbonyls (mainly glyoxal). The number of carbonylation sites increased with the harsher processing from raw milk (4) to pasteurized (16) and UHT milk (16) and to IF (24). Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Synthesis and Characterization of Tc(I) Carbonyl Nitrosyl Species Relevant to the Hanford Tank Waste: FY 2016 Status Report

    Energy Technology Data Exchange (ETDEWEB)

    Hall, Gabriel B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chatterjee, Sayandev [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Levitskaia, Tatiana G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Martin, Thibaut J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wall, Nathalie [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Walter, Eric D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-11-24

    Among long-lived radioactive constituents in the Hanford tank waste, Tc presents a unique challenge in that it exists predominantly in the liquid phase, generally in the anionic form of pertechnetate, TcO4-, which is highly volatile at low-activity waste (LAW) vitrification melter temperatures and mobile in the Hanford site’s subsurface environment. The complex behavior of Tc under storage, treatment, and immobilization conditions significantly affects its management options, which to-date remain uncertain. In strongly alkaline environments, Tc exists as pertechnetate, TcO4- (oxidation state +7), and in the reduced forms (oxidation state < +7) collectively known as non-pertechnetate species. Pertechnetate is a well-characterized, anionic Tc species that can be removed from LAW by anion exchange or solvent extraction methods. There is no definitive information on the origin of the non-pertechnetate Tc species, nor is there a comprehensive description of their composition and behavior. It has been recently proposed that the non-pertechnetate species can comprise Tc(I) metal center and carbonyl or mixed carbonyl nitrosyl ligands stabilizing low-valent Tc. Recent work by our group has significantly expanded this previous work, generating a series of Tc(I) carbonyl compounds and demonstrating that they can be generated from reduction of TcO4- in the simulated Hanford tank waste in presence of CO at elevated temperature (Levitskaia et al. 2014). These results are consistent with the previous proposal that [Tc(CO)3]+ species can be present in the Hanford tank waste and suggest that the low Tc(I) oxidation state is stabilized by the π-accepting ability of the CO ligands. The continuation work has been initiated to develop model Tc carbonyl nitrosyl compounds and investigate their potential presence in the Hanford tank wastes. This report summarizes our to-date results.

  6. The Emergence of Manganese-Based Carbonyl Hydrosilylation Catalysts.

    Science.gov (United States)

    Trovitch, Ryan J

    2017-11-21

    In recent years, interest in homogeneous manganese catalyst development has intensified because of the earth-abundant and nontoxic nature of this metal. Although compounds of Mn have largely been utilized for epoxidation reactions, recent efforts have revealed that Mn catalysts can mediate a broad range of reductive transformations. Low-valent Mn compounds have proven to be particularly effective for the hydrosilylation of carbonyl- and carboxylate-containing substrates, and this Account aims to highlight my research group's contributions to this field. In our initial 2014 communication, we reported that the bis(imino)pyridine-supported compound ( Ph2PPr PDI)Mn mediates ketone hydrosilylation with exceptional activity under solvent-free conditions. Silanes including Ph 2 SiH 2 , (EtO) 3 SiH, (EtO) 2 MeSiH, and (EtO)Me 2 SiH were found to partially reduce cyclohexanone in the presence of ( Ph2PPr PDI)Mn, while turnover frequencies of up to 1280 min -1 were observed using PhSiH 3 . This led us to evaluate the hydrosilylation of 11 additional ketones and allowed for the atom-efficient preparation of tertiary and quaternary silanes. At that time, it was also discovered that ( Ph2PPr PDI)Mn catalyzes the dihydrosilylation of esters (by way of acyl C-O bond hydrosilylation) to yield a mixture of silyl ethers with modest activity. Earlier this year, the scope of these transformations was extended to aldehydes and formates, and the observed hydrosilylation activities are among the highest obtained for any transition-metal catalyst. The effectiveness of three related catalysts has also been evaluated: ( Ph2PPr PDI)MnH, ( PyEt PDEA)Mn, and [( Ph2PEt PDI)Mn] 2 . To our surprise, ( Ph2PPr PDI)MnH was found to exhibit higher carboxylate dihydrosilylation activity than ( Ph2PPr PDI)Mn, while ( PyEt PDEA)Mn demonstrated remarkable carbonyl hydrosilylation activity considering that it lacks a redox-active supporting ligand. The evaluation of [( Ph2PEt PDI)Mn] 2 revealed

  7. Low pressure carbonylation of benzyl chloride = Die carbonylierung von benzylchlorid bei niedrigen drücken

    OpenAIRE

    Luggenhorst, H.J.; Westerterp, K.R.

    1986-01-01

    For carbonylations, metal carbonyls, particularly cobalt and iron carbonyls, are often used as catalysts. These reactions take place under rather drastic reaction conditions, e.g. 200–300 °C and 60–100 MPa. In some patents it is stated that similar reactions using the same catalysts can also be carried out under rather mild reaction conditions, such as 0–100 °C and 0–2.5 MPa. We studied the conversion of benzyl chloride to phenyl acetic methyl ester in a semi-batch reactor in which one of the...

  8. Mechanistic differences between methanol and dimethyl ether carbonylation in side pockets and large channels of mordenite.

    Science.gov (United States)

    Boronat, Mercedes; Martínez, Cristina; Corma, Avelino

    2011-02-21

    The activity and selectivity towards carbonylation presented by Brønsted acid sites located inside the 8MR pockets or in the main 12MR channels of mordenite is studied by means of quantum-chemical calculations, and the mechanistic differences between methanol and DME carbonylation are investigated. The selectivity towards carbonylation is higher inside the 8MR pockets, where the competitive formation of DME and hydrocarbons that finally leads to catalyst deactivation is sterically impeded. Moreover, inclusion of dispersion interactions in the calculations leads to agreement between the calculated activation barriers for the rate determining step and the experimentally observed higher reactivity of methoxy groups located inside the 8MR channels.

  9. Formation of neutral and charged gold carbonyls on highly facetted gold nanostructures

    Science.gov (United States)

    Chau, Thoi-Dai; Visart de Bocarmé, Thierry; Kruse, Norbert; Wang, Richard L. C.; Kreuzer, Hans Jürgen

    2003-12-01

    We show that gold mono- and di-carbonyls are formed on gold field emitter tips during interaction with carbon monoxide gas at room temperature and in the presence of high electrostatic fields. The experiments are done in a time-of-flight atom probe to obtain mass spectra. The yield of monocarbonyl cations is about twice that of di-carbonyl ions. Density functional theory calculations are reported that explain the field stabilization of adsorbed carbonyls and the desorption yield of their cations.

  10. Carbonylation of 1-hexene in the presence of palladium-anion-exchange resin catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Lapidus, A.L.; Pirozhkov, S.D.; Buiya, M.A.; Lunin, A.F.; Karapetyan, L.P.; Saldadze, K.M.

    1986-06-20

    Activated charcoal, silica gel, and zeolites containing palladium are active in the carbonylation of lower olefins by carbon monoxide. In the present work, they studied the carbonylation of 1-hexene in the presence of a series of palladium catalysts containing An-221, An-251, and AN-511 anion-exchange catalysts produced in the USSR as the supports. A catalyst obtained by the deposition of palladium(II) on weakly basic anion-exchange resins displays high efficiency in the carbonylation of 1-hexene with the formation of a nixture of enanthoic and 2-methylcaproic acids.

  11. Carbonyl(N-nitroso-N-oxido-1-naphtylamine-κ2O,O′(triphenylphosphine-κPrhodium(I acetone solvate

    Directory of Open Access Journals (Sweden)

    T. J. Muller

    2009-12-01

    Full Text Available The title compound, [Rh(C10H7N2O2(C18H15P(CO]·(CH32CO, is the second structural report of a metal complex formed with the O,O′-C10H7N2O2 (neocupferrate ligand. In the crystal structure, the metal centre is surrounded by one carbonyl ligand, one triphenylphosphine ligand and the bidentate neocupferrate ligand, forming a distorted square-planar RhCO2P coordination set which is best illustrated by the small O—Rh—O bite angle of 77.74 (10°. There are no classical hydrogen-bond interactions observed for this complex.

  12. Phenylalanine-a biogenic ligand with flexible η6- and η6:κ1-coordination at ruthenium(ii) centres

    KAUST Repository

    Reiner, Thomas; Jantke, Dominik; Miao, Xiaohe; Marziale, Alexander N.; Kiefer, Florian J.; Eppinger, Jö rg

    2013-01-01

    The reaction of (S)-2,5-dihydrophenylalanine 1 with ruthenium(iii) chloride yields the μ-chloro-bridged dimeric η6-phenylalanine ethyl ester complex 3, which can be converted into the monomeric analogue, η6:κ1-phenylalanine ethyl ester complex 12, under basic conditions. Studies were carried out to determine the stability and reactivity of complexes bearing η6- and η6: κ1-chelating phenylalanine ligands under various conditions. Reaction of 3 with ethylenediamine derivatives N-p-tosylethylenediamine or 1,4-di-N-p-tosylethylenediamine results in the formation of monomeric η6:κ1-phenylalanine ethyl ester complexes 14 and 15, which could be saponified yielding complexes 16 and 17 without changing the inner coordination sphere of the metal centre. The structure of η6:κ1-phenylalanine complex 17 and an N-κ1-phenylalanine complex 13 resulting from the reaction of 3 with an excess of pyridine were confirmed by X-ray crystallography. © 2013 The Royal Society of Chemistry.

  13. Thermal characterization of magnetically aligned carbonyl iron/agar composites.

    Science.gov (United States)

    Diaz-Bleis, D; Vales-Pinzón, C; Freile-Pelegrín, Y; Alvarado-Gil, J J

    2014-01-01

    Composites of magnetic particles into polymeric matrices have received increasing research interest due to their capacity to respond to external magnetic or electromagnetic fields. In this study, agar from Gelidium robustum has been chosen as natural biocompatible polymer to build the matrix of the magnetic carbonyl iron particles (CIP) for their uses in biomedical fields. Heat transfer behavior of the CIP-agar composites containing different concentrations (5, 10, 15, 20, 25 and 30% w/w) of magnetically aligned and non-aligned CIP in the agar matrix was studied using photothermal radiometry (PTR) in the back-propagation emission configuration. The morphology of the CIP-agar composites with aligned and non-aligned CIP under magnetic field was also evaluated by scanning electron microscopy (SEM). The results revealed a dominant effect of CIP concentration over the alignment patterns induced by the magnetic field, which agrees with the behavior of the thermal diffusivity and thermal conductivity. Agar served as a perfect matrix to be used with CIP, and CIP-agar composites magnetically aligned at 20% CIP concentration can be considered as promising 'smart' material for hyperthermia treatments in the biomedical field. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. The oceanic cycle and global atmospheric budget of carbonyl sulfide

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, P.S.

    1994-12-31

    A significant portion of stratospheric air chemistry is influenced by the existence of carbonyl sulfide (COS). This ubiquitous sulfur gas represents a major source of sulfur to the stratosphere where it is converted to sulfuric acid aerosol particles. Stratospheric aerosols are climatically important because they scatter incoming solar radiation back to space and are able to increase the catalytic destruction of ozone through gas phase reactions on particle surfaces. COS is primarily formed at the surface of the earth, in both marine and terrestrial environments, and is strongly linked to natural biological processes. However, many gaps in the understanding of the global COS cycle still exist, which has led to a global atmospheric budget that is out of balance by a factor of two or more, and a lack of understanding of how human activity has affected the cycling of this gas. The goal of this study was to focus on COS in the marine environment by investigating production/destruction mechanisms and recalculating the ocean-atmosphere flux.

  15. Plant Uptake of Atmospheric Carbonyl Sulfide in Coast Redwood Forests

    Science.gov (United States)

    Campbell, J. E.; Whelan, M. E.; Berry, J. A.; Hilton, T. W.; Zumkehr, A.; Stinecipher, J.; Lu, Y.; Kornfeld, A.; Seibt, U.; Dawson, T. E.; Montzka, S. A.; Baker, I. T.; Kulkarni, S.; Wang, Y.; Herndon, S. C.; Zahniser, M. S.; Commane, R.; Loik, M. E.

    2017-12-01

    The future resilience of coast redwoods (Sequoia sempervirens) is now of critical concern due to the detection of a 33% decline in California coastal fog over the 20th century. However, ecosystem-scale measurements of photosynthesis and stomatal conductance are challenging in coast redwood forests, making it difficult to anticipate the impacts of future changes in fog. To address this methodological problem, we explore coastal variations in atmospheric carbonyl sulfide (COS or OCS), which could potentially be used as a tracer of these ecosystem processes. We conducted atmospheric flask campaigns in coast redwood sites, sampling at surface heights and in the canopy ( 70 m), at the University of California Landels-Hill Big Creek Reserve and Big Basin State Park. We simulated COS atmosphere-biosphere exchange with a high-resolution 3-D model to interpret these data. Flask measurements indicated a persistent daytime drawdown between the coast and the downwind forest (45 ± 6 ppt COS) that is consistent with the expected relationship between COS plant uptake, stomatal conductance, and gross primary production. Other sources and sinks of COS that could introduce noise to the COS tracer technique (soils, anthropogenic activity, nocturnal plant uptake, and surface hydrolysis on leaves) are likely to be small relative to daytime COS plant uptake. These results suggest that COS measurements may be useful for making ecosystem-scale estimates of carbon, water, and energy exchange in coast redwood forests.

  16. Catalytic hydrogenation of carbonyl group for deuterated compound production

    International Nuclear Information System (INIS)

    Gluhoi, C. Andreea; Marginean, P.; Lazar, Diana; Almasan, V.

    1999-01-01

    The total deuterated isopropyl alcohol can be produced starting from acetone. The developed technology comprises two steps: Deuteration of acetone by H/D isotopic exchange between acetone and heavy water in homogeneous catalysis. Reduction of the deuterated acetone with deuterium in presence of a metal/support catalyst. H/D isotopic exchange reaction of the H atoms from CH 3 groups is easy to occur because carbonyl group weakens C-H bond (ceto-enolyc tautomery). The big difference between boiling points of acetone and water permits an easy separation of acetone by distillation method. The reduction of acetone with deuterium was performed in a dynamic reactor by passing a deuterium flow saturated with acetone vapour through a supported nickel catalyst bed. The reaction products were analysed on-line using a flame ionisation detector. The supported nickel catalysts were checked for this reaction. By using nickel over different supports the selectivity for isopropyl alcohol was about 100%. The propane was detected only as traces. The catalytic activity depends strongly on the support nature: the Ni/SiO 2 is less active, while the Ni/TiO 2 presents the larger value for the intrinsic activity. (authors)

  17. Global gridded anthropogenic emissions inventory of carbonyl sulfide

    Science.gov (United States)

    Zumkehr, Andrew; Hilton, Tim W.; Whelan, Mary; Smith, Steve; Kuai, Le; Worden, John; Campbell, J. Elliott

    2018-06-01

    Atmospheric carbonyl sulfide (COS or OCS) is the most abundant sulfur containing gas in the troposphere and is an atmospheric tracer for the carbon cycle. Gridded inventories of global anthropogenic COS are used for interpreting global COS measurements. However, previous gridded anthropogenic data are a climatological estimate based on input data that is over three decades old and are not representative of current conditions. Here we develop a new gridded data set of global anthropogenic COS sources that includes more source sectors than previously available and uses the most current emissions factors and industry activity data as input. Additionally, the inventory is provided as annually varying estimates from years 1980-2012 and employs a source specific spatial scaling procedure. We estimate a global source in year 2012 of 406 Gg S y-1 (range of 223-586 Gg S y-1), which is highly concentrated in China and is twice as large as the previous gridded inventory. Our large upward revision in the bottom-up estimate of the source is consistent with a recent top-down estimate based on air-monitoring and Antarctic firn data. Furthermore, our inventory time trends, including a decline in the 1990's and growth after the year 2000, are qualitatively consistent with trends in atmospheric data. Finally, similarities between the spatial distribution in this inventory and remote sensing data suggest that the anthropogenic source could potentially play a role in explaining a missing source in the global COS budget.

  18. Relationship between laparoscopic cholecystectomy operative time and carbonyl hemoglobin content

    Directory of Open Access Journals (Sweden)

    ZHANG Qi

    2013-06-01

    Full Text Available ObjectiveTo investigate whether operative time of laparoscopic cholecystectomy impacts the carbonyl hemoglobin (COHb concentration in peripheral blood. MethodsForty patients with gallstones and indications for laparoscopic cholecystectomy were enrolled in the study. Peripheral venous blood samples were collected at the beginning and end of the operative procedure. COHb concentration was measured by UV spectroscopy. The significance of changes in COHb concentration in relation to time of the operative procedure (rounded to the nearest minute was assessed by statistical correlation coefficient test. ResultsThe laparoscopic procedure was completed in 38 cases, and two patients required conversion to laparotomy. The content of COHb in peripheral venous blood had significantly increased during the laparoscopic operation (operation beginning: 11.07%±1.18% vs. operation end: 1.44%±0.26%, P<0.05. The change was positively correlated with operation time (r=0.85. ConclusionCarbon monoxide produced during the laparoscopic cholecystectomy procedure can lead to an increase in peripheral venous blood COHb. The longer the operation lasts, the greater the increase in COHb.

  19. Efficient and selective α-bromination of carbonyl compounds with N-bromosuccinimide under microwave

    KAUST Repository

    Guan, Xiao-Yu; Al-Misba'a, Zahra; Huang, Kuo-Wei

    2014-01-01

    A highly efficient method for the synthesis of α-halocarbonyl compounds has been achieved via selective monobromination of aromatic and aliphatic carbonyl compounds with N-bromosuccinimide catalyzed by p-toluenesulfonic acid under microwave irradiation within 30 min.

  20. Structure and Bonding in Binuclear Metal Carbonyls. Classical Paradigms vs. Insights from Modern Theoretical Calculations

    Czech Academy of Sciences Publication Activity Database

    Ponec, Robert

    2015-01-01

    Roč. 1053, SI (2015), s. 195-213 ISSN 2210-271X Institutional support: RVO:67985858 Keywords : binuclear metal carbonyls * DAFH analysis * 18-electron rule Subject RIV: CC - Organic Chemistry Impact factor: 1.403, year: 2015

  1. Nanostructured palladium tailored via carbonyl chemical route towards oxygen reduction reaction

    International Nuclear Information System (INIS)

    Luo, Y.; Mora-Hernández, J.M.; Estudillo-Wong, L.A.; Arce-Estrada, E.M.; Alonso-Vante, N.

    2015-01-01

    Graphical Abstract: Mass-depending morphologies of nanostructured Palladium obtained via the carbonyl chemical route. Display Omitted -- Highlights: •Mass-depending morphology was observed in nanostructured palladium supported on carbon prepared by the carbonyl chemical route. •The Morphological effect of carbon supported Pd was investigated towards ORR. -- Abstract: Carbon supported palladium nanostructures were synthesized via the carbonyl chemical route. Compared with nanostructured platinum, prepared via carbonyl chemical route, Pd nanomaterials showed mass-loading morphology, whereas particle size and morphology of Pt nanostructures was constant. The oxygen reduction reaction (ORR) on nanostructured Pd, with different morphology in both acid and alkaline medium was investigated. A relationship, based on X-ray diffraction structural analysis pattern, transmission electron microscope, with the Pd morphological effect on ORR activity was identified

  2. Deuterium enrichment by selective photo-induced dissociation of an organic carbonyl compound

    International Nuclear Information System (INIS)

    Marling, J.B.

    1981-01-01

    A deuterium-enriched material is produced by selective photoinduced dissociation of a gas phase organic carbonyl compound containing at least one hydrogen atom bonded to an atom adjacent to a carbonyl group. Alkyl carbonyl compounds such as acetone, acetaldehyde, trifluoroacetic acid, cyclobutanone, cyclopentanone, methyl acetate, 3,3-dimethyl-2-butanone, 2,4-pentanedione, and 4-methyl-2-pentanone are preferred. The carbonyl compound is subjected to intense infrared radiation from one laser, or two lasers operating at different frequencies, to selectively dissociate the deuterated molecules into stable products. The undissociated compound may be redeuterated by direct aqueous liquid phase H/D exchange, or by indirect liquid phase exchange using an alkanol in an intermediate step

  3. Efficient and selective α-bromination of carbonyl compounds with N-bromosuccinimide under microwave

    KAUST Repository

    Guan, Xiao-Yu

    2014-02-07

    A highly efficient method for the synthesis of α-halocarbonyl compounds has been achieved via selective monobromination of aromatic and aliphatic carbonyl compounds with N-bromosuccinimide catalyzed by p-toluenesulfonic acid under microwave irradiation within 30 min.

  4. Comparison of sampling methods for radiocarbon dating of carbonyls in air samples via accelerator mass spectrometry

    Science.gov (United States)

    Schindler, Matthias; Kretschmer, Wolfgang; Scharf, Andreas; Tschekalinskij, Alexander

    2016-05-01

    Three new methods to sample and prepare various carbonyl compounds for radiocarbon measurements were developed and tested. Two of these procedures utilized the Strecker synthetic method to form amino acids from carbonyl compounds with either sodium cyanide or trimethylsilyl cyanide. The third procedure used semicarbazide to form crystalline carbazones with the carbonyl compounds. The resulting amino acids and semicarbazones were then separated and purified using thin layer chromatography. The separated compounds were then combusted to CO2 and reduced to graphite to determine 14C content by accelerator mass spectrometry (AMS). All of these methods were also compared with the standard carbonyl compound sampling method wherein a compound is derivatized with 2,4-dinitrophenylhydrazine and then separated by high-performance liquid chromatography (HPLC).

  5. Comparison of sampling methods for radiocarbon dating of carbonyls in air samples via accelerator mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Schindler, Matthias, E-mail: matthias.schindler@physik.uni-erlangen.de; Kretschmer, Wolfgang; Scharf, Andreas; Tschekalinskij, Alexander

    2016-05-15

    Three new methods to sample and prepare various carbonyl compounds for radiocarbon measurements were developed and tested. Two of these procedures utilized the Strecker synthetic method to form amino acids from carbonyl compounds with either sodium cyanide or trimethylsilyl cyanide. The third procedure used semicarbazide to form crystalline carbazones with the carbonyl compounds. The resulting amino acids and semicarbazones were then separated and purified using thin layer chromatography. The separated compounds were then combusted to CO{sub 2} and reduced to graphite to determine {sup 14}C content by accelerator mass spectrometry (AMS). All of these methods were also compared with the standard carbonyl compound sampling method wherein a compound is derivatized with 2,4-dinitrophenylhydrazine and then separated by high-performance liquid chromatography (HPLC).

  6. Colour removal and carbonyl by-production in high dose ozonation for effluent polishing.

    Science.gov (United States)

    Mezzanotte, V; Fornaroli, R; Canobbio, S; Zoia, L; Orlandi, M

    2013-04-01

    Experimental tests have been conducted to investigate the efficiency and the by-product generation of high dose ozonation (10-60 mg O3 L(-1)) for complete colour removal from a treated effluent with an important component of textile dyeing wastewater. The effluent is discharged into an effluent-dominated stream where no dilution takes place, and, thus, the quality requirement for the effluents is particularly strict. 30, 60 and 90 min contact times were adopted. Colour was measured as absorbance at 426, 558 and 660 nm wavelengths. pH was monitored throughout the experiments. The experimental work showed that at 50 mg L(-1) colour removal was complete and at 60 mg O3 L(-1) the final aldehyde concentration ranged between 0.72 and 1.02 mg L(-1). Glyoxal and methylglyoxal concentrations were directly related to colour removal, whereas formaldehyde, acetaldehyde, acetone and acrolein were not. Thus, the extent of colour removal can be used to predict the increase in glyoxal and methylglyoxal concentrations. As colour removal can be assessed by a simple absorbance measurement, in contrast to the analysis of specific carbonyl compounds, which is much longer and complex, the possibility of using colour removal as an indicator for predicting the toxic potential of ozone by-products for textile effluents is of great value. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Microwave absorbing property of a hybrid absorbent with carbonyl irons coating on the graphite

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yonggang, E-mail: xuyonggang221@163.com [Science and Technology on Electromagnetic Scattering Laboratory, Shanghai, 200438 (China); Yan, Zhenqiang; Zhang, Deyuan [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, School of Mechanical Engineering and Automation, Beihang University, Beijing 100191 (China)

    2015-11-30

    Graphical abstract: The absorbing property could be enhanced as the CIPs coated on the graphite. - Highlights: • Absorbers filled with CIPs coating on the graphite was fabricated. • The permittivity and permeability increased as CIPs coated. • The CIP materials enhanced the electromagnetic property. • The graphite coated CIPs were effective in 2–18 GHz. - Abstract: The hybrid absorbent filled with carbonyl iron particles (CIPs) coating on the graphite was prepared using a chemical vapor decomposition (CVD) process. X-ray diffraction (XRD) patterns were done to analyze the particle crystal grain structure. The complex permittivity and permeability were measured using a vector network analyzer in the frequency range of 2–18 GHz. The results showed that α-Fe appeared in the super-lattice diffraction peaks in XRD graph. The composites added CIPs coating on the graphite had a higher permittivity and imaginary permeability due to the superior microwave dielectric loss and magnetic loss of the CIPs. The reflection loss (RL) result showed that composites filled with 5 vol% Fe-graphite had an excellent absorbing property in the 2–18 GHz, the minimum RL was −25.14 dB at 6 mm and −26.52 dB at 8 mm, respectively.

  8. Microwave absorbing property of silicone rubber composites with added carbonyl iron particles and graphite platelet

    International Nuclear Information System (INIS)

    Xu, Yonggang; Zhang, Deyuan; Cai, Jun; Yuan, Liming; Zhang, Wenqiang

    2013-01-01

    Silicone rubber composites filled with carbonyl iron particles (CIPs) and graphite platelet (GP) were prepared using non-coating or coating processes. The complex permittivity and permeability of the composites were measured using a vector network analyzer in the frequency range of 1–18 GHz and dc electric conductivity was measured by the standard four-point contact method. The results showed that CIPs/GP composites fabricated in the coating process had the highest permittivity and permeability due to the particle orientation and interactions between the two absorbents. The coating process resulted in a decreased effective eccentricity of the absorbents, and the dc conductivity increased according to Neelakanta's equations. The reflection loss (RL) value showed that the composites had an excellent absorbing property in the L-band, minimum −11.85 dB at 1.5 mm and −15.02 dB at 2 mm. Thus, GP could be an effective additive in preparing thin absorbing composites in the L-band. - Highlights: ► The added GP increased the permittivity and permeability of composites filled with CIPs. ► The enhancement was owing to interactions of the two absorbents and the fabrication process. ► The coating process decreased the effective eccentricity of the particles, and increased the conductivity of the composites. ► The composites to which CIPs/GP were added in coating process had excellent absorbing properties in the L-band.

  9. Coupling of metal-based light-harvesting antennas and electron-donor subunits: Trinuclear Ruthenium(II) complexes containing tetrathiafulvalene-substituted polypyridine ligands

    DEFF Research Database (Denmark)

    Campagna, Sebastiano; Serroni, Scolastica; Puntoriero, Fausto

    2002-01-01

    in fluid solution at room temperature. Time-resolved transient absorption spectroscopy confirmed that the potentially luminescent MLCT states of 7-10 are significantly shorter lived than the corresponding states of the model species. Photoinduced electron-transfer processes from the TTF moieties...

  10. Fluoride-Mediated Dephosphonylation of α-Diazo-β-carbonyl Phosphonates.

    Science.gov (United States)

    Phatake, Ravindra S; Mullapudi, Venkannababu; Wakchaure, Vivek C; Ramana, Chepuri V

    2017-01-20

    The possibility of fluoride-mediated selective dephosphonylation of α-diazo-β-carbonyl phosphonates such as the Ohira-Bestmann reagent has been proposed and executed. The resulting α-diazocarbonyl intermediates undergo a (3 + 2)-cycloaddition at room temperature with conjugated olefins and benzynes. Interestingly, under the current conditions, the resulting cycloaddition products underwent either N-acylation (with excess α-diazo-β-carbonyl phosphonates) or Michael addition (with conjugated olefins).

  11. Structure and Reactivity of Zeolite- and Carbon-Supported Catalysts for the Oxidative Carbonylation of Alcohols

    OpenAIRE

    Briggs, Daniel Neal

    2010-01-01

    AbstractStructure and Reactivity of Zeolite- and Carbon-Supported Catalysts for the Oxidative Carbonylation of AlcoholsbyDaniel Neal BriggsDoctor of Philosophy in Chemical EngineeringUniversity of California, BerkeleyProfessor Alexis T. Bell, Chair The oxidative carbonylation of alcohols to produce dialkyl carbonates is a process that takes place commercially in a slurry of cuprous chloride in the appropriate alcohol. While this process is chemically efficient, it incurs costs in terms of ene...

  12. Chemoselective Reduction and Alkylation of Carbonyl Functions Using Phosphonium Salts as an in Situ Protecting Groups.

    Science.gov (United States)

    Ohta, Reiya; Fujioka, Hiromichi

    2017-01-01

    Recent progress in the chemoselective reduction and alkylation of carbonyl functions using our in situ protection method is described. Methods that enable reversal or control of the reactivity of a carbonyl functional group are potentially useful. They open up new areas of synthetic organic chemistry and change the concept of retrosynthesis because they remove the need for complicated protection/deprotection sequences. In this account, we discuss the strategy and applications of our in situ protection method using phosphonium salts.

  13. Cytoprotective Effects of Pumpkin (Cucurbita Moschata) Fruit Extract against Oxidative Stress and Carbonyl Stress.

    Science.gov (United States)

    Shayesteh, Reyhaneh; Kamalinejad, Mohammad; Adiban, Hasan; Kardan, Azin; Keyhanfar, Fariborz; Eskandari, Mohammad Reza

    2017-10-01

    Background Diabetes mellitus is a chronic endocrine disorder that is associated with significant mortality and morbidity due to microvascular and macrovascular complications. Diabetes complications accompanied with oxidative stress and carbonyl stress in different organs of human body because of the increased generation of free radicals and impaired antioxidant defense systems. In the meantime, reactive oxygen species (ROS) and reactive carbonyl species (RCS) have key mediatory roles in the development and progression of diabetes complications. Therapeutic strategies have recently focused on preventing such diabetes-related abnormalities using different natural and chemical compounds. Pumpkin ( Cucurbita moschata ) is one of the most important vegetables in the world with a broad-range of pharmacological activities such as antihyperglycemic effect. Methods In the present study, the cytoprotective effects of aqueous extract of C. moschata fruit on hepatocyte cytotoxicity induced by cumene hydroperoxide (oxidative stress model) or glyoxal (carbonylation model) were investigated using freshly isolated rat hepatocytes. Results The extract of C. moschata (50 μg/ml) excellently prevented oxidative and carbonyl stress markers, including hepatocyte lysis, ROS production, lipid peroxidation, glutathione depletion, mitochondrial membrane potential collapse, lysosomal damage, and cellular proteolysis. In addition, protein carbonylation was prevented by C. moschata in glyoxal-induced carbonyl stress. Conclusion It can be concluded that C. moschata has cytoprotective effects in oxidative stress and carbonyl stress models and this valuable vegetable can be considered as a suitable herbal product for the prevention of toxic subsequent of oxidative stress and carbonyl stress seen in chronic hyperglycemia. © Georg Thieme Verlag KG Stuttgart · New York.

  14. Organocatalyzed α-Sulfenylation of carbonyl compounds using N-formly/Acyl Sulfenmides

    International Nuclear Information System (INIS)

    Noh, Hyeon Wan; Lee, Chan; Jang, Hye Young

    2017-01-01

    α-Sulfenylation of aldehydes and ketones using N-formyl and N-acyl sulfenamides, prepared by Cu-catalyzed aerobic coupling of amides and thiols, was achieved in the presence of cyclic secondary amine⋅HCl catalysts. To obtain various sulfur-functionalized carbonyl compounds, sulfenamides containing aromatic and aliphatic organosulfur were investigated. As carbonyl compounds, cyclic and acyclic ketones, 1,3-dicarbonyl compounds, and aldehydes were investigated, affording the desired α-sulfenylation products in good yields

  15. Organocatalyzed α-Sulfenylation of carbonyl compounds using N-formly/Acyl Sulfenmides

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Hyeon Wan; Lee, Chan; Jang, Hye Young [Dept. of Energy Systems Research, Ajou University, Suwon (Korea, Republic of)

    2017-03-15

    α-Sulfenylation of aldehydes and ketones using N-formyl and N-acyl sulfenamides, prepared by Cu-catalyzed aerobic coupling of amides and thiols, was achieved in the presence of cyclic secondary amine⋅HCl catalysts. To obtain various sulfur-functionalized carbonyl compounds, sulfenamides containing aromatic and aliphatic organosulfur were investigated. As carbonyl compounds, cyclic and acyclic ketones, 1,3-dicarbonyl compounds, and aldehydes were investigated, affording the desired α-sulfenylation products in good yields.

  16. Ammonia synthesis in the presence of rhodium-ruthenium-iridium carbonyl clusters

    International Nuclear Information System (INIS)

    Fedoseev, I.V.; Solov'ev, N.V.

    2007-01-01

    Researches in the field of platinum metal coordination compounds, where nitrogen enters as a ligand in coordination sphere of metal, are discussed. Results of experiments on the ammonia synthesis during the CO+N 2 mixture passing through alkali solution containing mixture of carbonyl clusters of rhodium, ruthenium and iridium at atmospheric pressure are given. Technique of the experiment and steps of assumed reactions of nitrogen fixation by Rh, Ir and Ru carbonyl clusters are demonstrated [ru

  17. Plasma-treated carbonyl iron particles as a dispersed phase in magnetorheological fluids

    OpenAIRE

    Sedlačík, M.; Pavlínek, V.; Lehocký, M.; Mráček, A.; Grulich, O.; Švrčinová, P. (Petra); Filip, P. (Petr); Vesel, A.

    2011-01-01

    The aim of this paper is to document suitability of plasma-treated carbonyl iron particles as a dispersed phase in magnetorheological fluids. Surface-modified carbonyl iron particles were prepared via their exposure to 50% argon and 50% octafluorocyclobutane plasma. The X-ray photoelectron spectroscopy was used for analysis of chemical bonding states in the surface layer. Plasma-treated particles were adopted for a dispersed phase in magnetorheological (MR) fluids, and the MR behaviour was in...

  18. Selective transformation of carbonyl ligands to organic molecules: Progress report, 1 September 1986--31 August 1989

    Energy Technology Data Exchange (ETDEWEB)

    Cutler, A.R.

    1989-04-18

    Studies on anionic phosphido alkyl and acetyl complexes Cp(CO)(PPh/sub 2/)Fe /minus/ R/sup /minus// (1) and In(CO)(PPh/sub 2/)Fe /minus/ R/sup /minus// (2) (R = CH/sub 3/ (a), COCH/sub 3/ (b); In = /eta//sup 5/-indenyl) and their neutral phosphine derivatives Cp(CO)(PPh/sub 2/H)Fe /minus/ R (3) and In(CO)(PPh/sub 2/H)Fe /minus/ R (4) are complete. Attempts to carbonylate 1a and 2a to 1b and 2b failed; also, 3a and 4a resist carbonylation. Reacting 1b with MeI affords a neutral PPh/sub 2/Me acetyl compound 5, whereas MeOSO/sub 2/CF/sub 3/ gives the Fischer carbene complex Cp(PPh/sub 2/)(CO) Fe = C(OMe)CH/sub 3/ (6). Carbene 6 isomerizes to 5 at room temperature. Reaction conditions have been optimized for tenerating vinylidene compounds In/sub 2/(CO)/sub 3/Fe/sub 2/ ..mu..-(C = CHR) from InFe(CO)/sub 2//sup /minus// and In(CO)/sub 2/Fe /minus/ CH/sub 2/R (R = H, Me, OMe). The bimetallic carbonylation procedure for converting Fp/sup /minus//(Li/sup +/, Na/sup +/, PPN/sup +/) and In(CO)/sub 2/Fe /minus/ CH/sub 3/ to InCp(CO)/sub 3/Fe/sub 2/(COCH/sub 3//sup /minus//) and then regioselectively to FpCOCH/sub 3/ (1 atm CO) has been optimized. Studies are finished on the diastereofacial selectivity observed during reduction of the alkoxycarbenes Cp(P(OR)/sub 3/)(CO)Fe = C(OCH/sub 3/)CH/sub 3//sup +/ (R = Me, Ph) with borohydride reagents R/sub 3/BH/sup /minus// (Li/sup +/, Na/sup +/, K/sup +/) and with (PPh/sub 3/CuH)/sub 6/. A survey of the Rh(I)-catalyzed hydrosilation of a variety of iron acyl complexes has been concluded.

  19. Role of protein-bound carbonyl groups in the formation of advanced glycation endproducts.

    Science.gov (United States)

    Liggins, J; Furth, A J

    1997-08-22

    Several mechanisms have been postulated for the formation of advanced glycation endproducts (AGEs) from glycated proteins; they all feature protein-bound carbonyl intermediates. Using 2,4-dinitrophenylhydrazine (DNPH), we have detected these intermediates on bovine serum albumin, lysozyme and beta-lactoglobulin after in vitro glycation by glucose or fructose. Carbonyls were formed in parallel with AGE-fluorophores, via oxidative Maillard reactions. Neither Amadori nor Heyns products contributed to the DNPH reaction. Fluorophore and carbonyl yields were much enhanced in lipid-associated proteins, but both groups could also be detected in lipid-free proteins. When pre-glycated proteins were incubated in the absence of free sugar, carbonyl groups were rapidly lost in a first-order reaction, while fluorescence continued to develop beyond the 21 days of incubation. Another unexpected finding was that not all carbonyl groups were blocked by aminoguanidine, although there was complete inhibition of reactions leading to AGE-fluorescence. It is suggested that carbonyls acting as fluorophore precursors react readily with aminoguanidine, while others are resistant to this hydrazine, possibly because they are involved in ring closure. Factors influencing the relative rates of acyclisation and hydrazone formation are discussed, together with possible implications for antiglycation therapy.

  20. Carbonyl Emissions in E-cigarette Aerosol: A Systematic Review and Methodological Considerations

    Directory of Open Access Journals (Sweden)

    Konstantinos E. Farsalinos

    2018-01-01

    Full Text Available Carbonyl emissions from tobacco cigarettes represent a substantial health risk contributing to smoking-related morbidity and mortality. As expected, this is an important research topic for tobacco harm reduction products, in an attempt to compare the relative risk of these products compared to tobacco cigarettes. In this study, a systematic review of the literature available on PubMed was performed analyzing the studies evaluating carbonyl emissions from e-cigarettes. A total of 32 studies were identified and presented. We identified a large diversity of methodologies, with substantial discrepancies in puffing patterns, aerosol collection and analytical methods as well as reported units of measurements. Such discrepancies make comparisons difficult, and in some cases the accuracy of the findings cannot be determined. Importantly, control for the generation of dry puffs was not performed in the vast majority of studies, particularly in studies using variable power devices, which could result in testing conditions and reported carbonyl levels that have no clinical relevance or context. Some studies have been replicated, verifying the presence of dry puff conditions. Whenever realistic use conditions were ensured, carbonyl emissions from e-cigarettes were substantially lower than tobacco cigarette smoke, while newer generation (bottom-coil, cotton wick atomizers appeared to emit minimal levels of carbonyls with questionable clinical significance in terms of health risk. However, extremely high levels of carbonyl emissions were reported in some studies, and all these studies need to be replicated because of potentially important health implications.

  1. Predicting personal exposure to airborne carbonyls using residential measurements and time/activity data

    Science.gov (United States)

    Liu, Weili; Zhang, Junfeng (Jim); Korn, Leo R.; Zhang, Lin; Weisel, Clifford P.; Turpin, Barbara; Morandi, Maria; Stock, Tom; Colome, Steve

    As a part of the Relationships of Indoor, Outdoor, and Personal Air (RIOPA) study, 48 h integrated residential indoor, outdoor, and personal exposure concentrations of 10 carbonyls were simultaneously measured in 234 homes selected from three US cities using the Passive Aldehydes and Ketones Samplers (PAKS). In this paper, we examine the feasibility of using residential indoor concentrations to predict personal exposures to carbonyls. Based on paired t-tests, the means of indoor concentrations were not different from those of personal exposure concentrations for eight out of the 10 measured carbonyls, indicating indoor carbonyls concentrations, in general, well predicted the central tendency of personal exposure concentrations. In a linear regression model, indoor concentrations explained 47%, 55%, and 65% of personal exposure variance for formaldehyde, acetaldehyde, and hexaldehyde, respectively. The predictability of indoor concentrations on cross-individual variability in personal exposure for the other carbonyls was poorer, explainingexposure concentrations. It was found that activities related to driving a vehicle and performing yard work had significant impacts on personal exposures to a few carbonyls.

  2. COMPARATIVE STUDY OF EFFICACY OF FERROUS SULPHATE AND CARBONYL IRON IN ANEMIA OF ANTENATAL WOMEN

    Directory of Open Access Journals (Sweden)

    Radhika

    2015-03-01

    Full Text Available Iron deficiency anemia is the most common and important public health problem all over the world in the risk group of antenatal women. Research is going on to improve the iron status of the pregnant women with different forms of iron available. In this regard, Carbonyl Iron is showing promising results in improving the red cell mass with better compliance. 120 antenatal women were recruited in this study. The study comprised of 6weeks for each patient. They were given Carbonyl Iron 100 mg/day and FeS04 100gm/day . Before and after treatment all the baseline and specific investigations were one. Results were tabulated, comparison and significance were tested by unpaired student ’s’ test and their 'p' value was calculated. Results were shown graphically also. Carbonyl Iron showed improvement in hemoglobin, PCV and better than ferrous Sulphate (P <0.001. Incidence of side effects were less with Carbonyl Iron than Ferrous Sulphate, better compliance was seen with Carbonyl Iron. In conclusion, the present study s howed that Carbonyl Iron had better efficacy and safety in the management of Iron deficiency anemia in antenatal women than ferrous Sulphate

  3. Protein carbonylation associated to high-fat, high-sucrose diet and its metabolic effects.

    Science.gov (United States)

    Méndez, Lucía; Pazos, Manuel; Molinar-Toribio, Eunice; Sánchez-Martos, Vanesa; Gallardo, José M; Rosa Nogués, M; Torres, Josep L; Medina, Isabel

    2014-12-01

    The present research draws a map of the characteristic carbonylation of proteins in rats fed high-caloric diets with the aim of providing a new insight of the pathogenesis of metabolic diseases derived from the high consumption of fat and refined carbohydrates. Protein carbonylation was analyzed in plasma, liver and skeletal muscle of Sprague-Dawley rats fed a high-fat, high-sucrose (HFHS) diet by a proteomics approach based on carbonyl-specific fluorescence-labeling, gel electrophoresis and mass spectrometry. Oxidized proteins along with specific sites of oxidative damage were identified and discussed to illustrate the consequences of protein oxidation. The results indicated that long-term HFHS consumption increased protein oxidation in plasma and liver; meanwhile, protein carbonyls from skeletal muscle did not change. The increment of carbonylation by HFHS diet was singularly selective on specific target proteins: albumin from plasma and liver, and hepatic proteins such as mitochondrial carbamoyl-phosphate synthase (ammonia), mitochondrial aldehyde dehydrogenase, argininosuccinate synthetase, regucalcin, mitochondrial adenosine triphosphate synthase subunit beta, actin cytoplasmic 1 and mitochondrial glutamate dehydrogenase 1. The possible consequences that these specific protein carbonylations have on the excessive weight gain, insulin resistance and nonalcoholic fatty liver disease resulting from HFHS diet consumption are discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Line profile analyses of rhodium metal obtained by decomposition of rhodium carbonyl

    International Nuclear Information System (INIS)

    Chandra, D.; Mandalia, H.; Garner, M.L.; Blakely, M.K.; Lau, K.H.

    1995-01-01

    Metal carbonyls are important for chemical vapor deposition (CVD) of metals and alloys and formation of high surface area metallic particles which have potential applications as catalysts. Rhodium carbonyl [Rh 6 (CO) 16 ] produces high surface area metallic particles whose structure has been reported as monoclinic (I2/a) with lattice dimensions, a=17.00(±0.03)Angstrom, b=9.78(±0.02)Angstrom, c=17.53(±0.03)Angstrom and Β=121 degrees 45' ± 30' at room temperature. Generally, metal carbonyl crystals dissociate under vacuum as carbonyl gas and decompose to metallic crystals and carbon monoxide at higher temperatures. However, the behavior of rhodium carbonyl crystals is different; they decompose directly to metallic rhodium without the formation of rhodium carbonyl gas in vacuum. Several residual fine grains of rhodium metal are found after the decomposition in vacuum at relatively low temperatures. The metallic samples of rhodium were obtained from vapor pressure experiments using torsion Knudsen-effusion apparatus. X-ray diffraction analyses performed on these gains showed severely broadened Bragg reflections indicative of small particle size and/or lattice microgram. In this study, a comparison of lattice strains and domain sizes obtained by integral breadth and Fourier methods has been made. In addition a comparison of the lattice strains and domain sizes has been made between the Cauchy, Gaussian, Cauchy-Gaussian and Aqua integral breadth methods

  5. Characteristics of carbonyl compounds in public vehicles of Beijing city: Concentrations, sources, and personal exposures

    Science.gov (United States)

    Pang, Xiaobing; Mu, Yujing

    The characteristics of carbonyl compounds (carbonyls) including concentrations, major sources, and personal exposure were investigated for 29 vehicles including taxi, bus and subway in Beijing. It was found that the taxis (Xiali, TA) and buses (Huanghe, BA) fueled by gasoline with longer service years had the higher indoor carbonyl levels (178±42.7 and 188±31.6 μg m -3) while subways energized by electricity without exhaust and the jingwa buses (BB) driven in the suburb had the lower levels with total concentrations of 98.5±26.3 and 92.1±20.3 μg m -3, respectively. Outdoor carbonyls of taxi cars and buses were nearly at the same level with their total concentrations varying from 80 to 110 μg m -3. The level of outdoor subways carbonyls was equal with the ambient air levels. Exhaust leakage, indoor material emissions, photochemical formation, and infiltration of outdoor air were considered to be the major sources to in-vehicle carbonyls. Personal exposures and cancer risk to formaldehyde and acetaldehyde were calculated for professional bus and taxi drivers, respectively. Taxi drivers had the highest cancer risk with personal exposure to formaldehyde and acetaldehyde of 212 and 243 μg day -1, respectively. The public concern should pay considerable attention to professional drivers' health.

  6. Protein carbonylation, protein aggregation and neuronal cell death in a murine model of multiple sclerosis

    Science.gov (United States)

    Dasgupta, Anushka

    Many studies have suggested that oxidative stress plays an important role in the pathophysiology of both multiple sclerosis (MS) and its animal model experimental autoimmune encephalomyelitis (EAE). Yet, the mechanism by which oxidative stress leads to tissue damage in these disorders is unclear. Recent work from our laboratory has revealed that protein carbonylation, a major oxidative modification caused by severe and/or chronic oxidative stress conditions, is elevated in MS and EAE. Furthermore, protein carbonylation has been shown to alter protein structure leading to misfolding/aggregation. These findings prompted me to hypothesize that carbonylated proteins, formed as a consequence of oxidative stress and/or decreased proteasomal activity, promote protein aggregation to mediate neuronal apoptosis in vitro and in EAE. To test this novel hypothesis, I first characterized protein carbonylation, protein aggregation and apoptosis along the spinal cord during the course of myelin-oligodendrocyte glycoprotein (MOG)35-55 peptide-induced EAE in C57BL/6 mice [Chapter 2]. The results show that carbonylated proteins accumulate throughout the course of the disease, albeit by different mechanisms: increased oxidative stress in acute EAE and decreased proteasomal activity in chronic EAE. I discovered not only that there is a temporal correlation between protein carbonylation and apoptosis but also that carbonyl levels are significantly higher in apoptotic cells. A high number of juxta-nuclear and cytoplasmic protein aggregates containing the majority of the oxidized proteins are also present during the course of EAE, which seems to be due to reduced autophagy. In chapter 3, I show that when gluthathione levels are reduced to those in EAE spinal cord, both neuron-like PC12 (nPC12) cells and primary neuronal cultures accumulate carbonylated proteins and undergo cell death (both by necrosis and apoptosis). Immunocytochemical and biochemical studies also revealed a temporal

  7. Simultaneous detection of low and high molecular weight carbonylated compounds derived from lipid peroxidation by electrospray ionization-tandem mass spectrometry.

    Science.gov (United States)

    Milic, Ivana; Hoffmann, Ralf; Fedorova, Maria

    2013-01-02

    Reactive oxygen species (ROS) and other oxidative agents such as free radicals can oxidize polyunsaturated fatty acids (PUFA) as well as PUFA in lipids. The oxidation products can undergo consecutive reactions including oxidative cleavages to yield a chemically diverse group of products, such as lipid peroxidation products (LPP). Among them are aldehydes and ketones ("reactive carbonyls") that are strong electrophiles and thus can readily react with nucleophilic side chains of proteins, which can alter the protein structure, function, cellular distribution, and antigenicity. Here, we report a novel technique to specifically derivatize both low molecular and high molecular weight carbonylated LPP with 7-(diethylamino)coumarin-3-carbohydrazide (CHH) and analyze all compounds by electrospray ionization-mass spectrometry (ESI-MS) in positive ion mode. CHH-derivatized compounds were identified by specific neutral losses or fragment ions. The fragment ion spectra displayed additional signals that allowed unambiguous identification of the lipid, fatty acids, cleavage sites, and oxidative modifications. Oxidation of docosahexaenoic (DHA, 22:6), arachidonic (AA, 20:4), linoleic (LA, 18:2), and oleic acids (OA, 18:1) yielded 69 aliphatic carbonyls, whose structures were all deduced from the tandem mass spectra. When four phosphatidylcholine (PC) vesicles containing the aforementioned unsaturated fatty acids were oxidized, we were able to deduce the structures of 122 carbonylated compounds from the tandem mass spectra of a single shotgun analysis acquired within 15 min. The high sensitivity (LOD ∼ 1 nmol/L for 4-hydroxy-2-nonenal, HNE) and a linear range of more than 3 orders of magnitude (10 nmol/L to 10 μmol/L for HNE) will allow further studies on complex biological samples including plasma.

  8. Fast retrievals of tropospheric carbonyl sulfide with IASI

    Science.gov (United States)

    Vincent, R. Anthony; Dudhia, Anu

    2017-02-01

    Iterative retrievals of trace gases, such as carbonyl sulfide (OCS), from satellites can be exceedingly slow. The algorithm may even fail to keep pace with data acquisition such that analysis is limited to local events of special interest and short time spans. With this in mind, a linear retrieval scheme was developed to estimate total column amounts of OCS at a rate roughly 104 times faster than a typical iterative retrieval. This scheme incorporates two concepts not utilized in previously published linear estimates. First, all physical parameters affecting the signal are included in the state vector and accounted for jointly, rather than treated as effective noise. Second, the initialization point is determined from an ensemble of atmospheres based on comparing the model spectra to the observations, thus improving the linearity of the problem. All of the 2014 data from the Infrared Atmospheric Sounding Interferometer (IASI), instruments A and B, were analysed and showed spatial features of OCS total columns, including depletions over tropical rainforests, seasonal enhancements over the oceans, and distinct OCS features over land. Error due to assuming linearity was found to be on the order of 11 % globally for OCS. However, systematic errors from effects such as varying surface emissivity and extinction due to aerosols have yet to be robustly characterized. Comparisons to surface volume mixing ratio in situ samples taken by NOAA show seasonal correlations greater than 0.7 for five out of seven sites across the globe. Furthermore, this linear scheme was applied to OCS, but may also be used as a rapid estimator of any detectable trace gas using IASI or similar nadir-viewing instruments.

  9. Plasma protein carbonyl responses to anaerobic exercise in female cyclists

    Directory of Open Access Journals (Sweden)

    M.E Afzalpour

    2016-03-01

    Full Text Available Single bouts of aerobic exercise may leads to oxidative stress due to the use of oxygen for metabolism and the generation of reactive oxygen. In athletes, oxidative stress can lead to several deleterious performance effects, such as muscular oxidative damage, muscle soreness, loss of skeletal muscle force production and/or inflammation. However, little is known regarding the severity and duration of oxidative stress arising from intensive anaerobic modes of exercise in aerobically-trained athletes. The purpose of this study was to investigate the effect of a single bout of intensive anaerobic exercise on plasma protein carbonyl (PC in aerobically-trained women. Aerobically-trained, provincial female cyclists [n = 18, age: 24.2±2.7 years; stature: 163.6±4.6 cm; body mass: 53.4±4.2 kg] were randomly assigned into either a non-exercising control (CON; n = 9 or experimental (EXP; n = 9 group that underwent a 30-second anaerobic (Wingate cycle ergometer exercise session. Blood sampling took place before exercise, immediately after the exercise (IE, and 24 hours following the exercise (24HR bout. In the EXP, results indicated significant (P ≤ 0.05 differences in PC levels between the pre-test and IE (0.010±0.0124 to 0.0149±0.0420 mmol/milt; P = 0.010, and IE and 24HR (0.0149±0.0420 to 0.0111±0.0183 mmol/milt; P = 0.013. No significant differences were observed between pre-test and 24HR (0.010±0.0124 to 0.0111±0.0183 mmol/milt; P = 0.371. These results indicate that oxidative protein damage, as indicated by PC levels, rises immediately with the onset of anaerobic exercise, but returns to resting levels within 24 hours following exercise in aerobically-trained women.

  10. Bifunctional (cyclopentadienone)iron-tricarbonyl complexes: Synthesis, computational studies and application in reductive amination

    KAUST Repository

    Moulin, Solenne; Dentel, Hé lè ne; Pagnoux-Ozherelyeva, Anastassiya; Gaillard, Sylvain; Poater, Albert; Cavallo, Luigi; Lohier, Jean Franç ois; Renaud, Jean Luc

    2013-01-01

    . Festival of amination: Two series of modified Knölker's complexes were synthesised and applied in the reductive amination of various carbonyl derivatives with primary or secondary amines (see scheme, TIPS = triisopropylsilyl). For a mechanistic insight

  11. Bis(bipyridine)ruthenium(II) complexes with an aliphatic sulfinato donor: synthesis, characterization, and properties.

    Science.gov (United States)

    Tamura, Motoshi; Tsuge, Kiyoshi; Igashira-Kamiyama, Asako; Konno, Takumi

    2011-06-06

    Treatment of a thiolato-bridged Ru(II)Ag(I)Ru(II) trinuclear complex, [Ag{Ru(aet)(bpy)(2)}(2)](3+) (aet = 2-aminoethanthiolate; bpy = 2,2'-bipyridine), with NaI in aqueous ethanol under an aerobic condition afforded a mononuclear ruthenium(II) complex having an S-bonded sulfinato group, [1](+) ([Ru(aesi-N, S)(bpy)(2)](+) (aesi = 2-aminoethanesulfinate)). Similar treatment of optically active isomers of an analogous Ru(II)Ag(I)Ru(II) trinuclear complex, Δ(D)Δ(D)- and Λ(D)Λ(D)-[Ag{Ru(d-Hpen-O,S)(bpy)(2)}(2)](3+) (d-pen = d-penicillaminate), with NaI also produced mononuclear ruthenium(II) isomers with an S-bonded sulfinato group, Δ(D)- and Λ(D)-[2](+) ([Ru(d-Hpsi-O,S)(bpy)(2)](+) (d-psi = d-penicillaminesulfinate)), respectively, retaining the bidentate-O,S coordination mode of a d-Hpen ligand and the absolute configuration (Δ or Λ) about a Ru(II) center. On refluxing in water, the Δ(D) isomer of [2](+) underwent a linkage isomerization to form Δ(D)-[3] (+) ([Ru(d-Hpsi-N,S)(bpy)(2)](+)), in which a d-Hpsi ligand coordinates to a Ru(II) center in a bidentate-N,S mode. Complexes [1](+), Δ(D)- and Λ(D)-[2](+), and Δ(D)-[3](+) were fully characterized by electronic absorption, CD, NMR, and IR spectroscopies, together with single-crystal X-ray crystallography. The electrochemical properties of these complexes, which are highly dependent on the coordination mode of sulfinate ligands, are also described. © 2011 American Chemical Society

  12. Molecular Engineering with Organic Carbonyl Electrode Materials for Advanced Stationary and Redox Flow Rechargeable Batteries.

    Science.gov (United States)

    Zhao, Qing; Zhu, Zhiqiang; Chen, Jun

    2017-12-01

    Organic carbonyl electrode materials that have the advantages of high capacity, low cost and being environmentally friendly, are regarded as powerful candidates for next-generation stationary and redox flow rechargeable batteries (RFBs). However, low carbonyl utilization, poor electronic conductivity and undesired dissolution in electrolyte are urgent issues to be solved. Here, we summarize a molecular engineering approach for tuning the capacity, working potential, concentration of active species, kinetics, and stability of stationary and redox flow batteries, which well resolves the problems of organic carbonyl electrode materials. As an example, in stationary batteries, 9,10-anthraquinone (AQ) with two carbonyls delivers a capacity of 257 mAh g -1 (2.27 V vs Li + /Li), while increasing the number of carbonyls to four with the formation of 5,7,12,14-pentacenetetrone results in a higher capacity of 317 mAh g -1 (2.60 V vs Li + /Li). In RFBs, AQ, which is less soluble in aqueous electrolyte, reaches 1 M by grafting -SO 3 H with the formation of 9,10-anthraquinone-2,7-disulphonic acid, resulting in a power density exceeding 0.6 W cm -2 with long cycling life. Therefore, through regulating substituent groups, conjugated structures, Coulomb interactions, and the molecular weight, the electrochemical performance of carbonyl electrode materials can be rationally optimized. This review offers fundamental principles and insight into designing advanced carbonyl materials for the electrodes of next-generation rechargeable batteries. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Proteomic identification of carbonylated proteins in F344 rat hippocampus after 1-bromopropane exposure

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Zhenlie [Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya 466‐8550 (Japan); Department of Toxicology, Guangdong Prevention and Treatment Center for Occupational Diseases, Guangzhou 510‐300 (China); Ichihara, Sahoko [Graduate School of Regional Innovation Studies, Mie University, Tsu 514‐8507 (Japan); Oikawa, Shinji [Department of Environmental and Molecular Medicine, Mie University Graduate School of Medicine, Mie 514‐8507 (Japan); Chang, Jie; Zhang, Lingyi; Subramanian, Kaviarasan; Mohideen, Sahabudeen Sheik [Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya 466‐8550 (Japan); Ichihara, Gaku, E-mail: gak@med.nagoya-u.ac.jp [Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya 466‐8550 (Japan)

    2012-08-15

    1-Bromopropane (1-BP) is neurotoxic in both experimental animals and humans. Previous proteomic analysis of rat hippocampus implicated alteration of protein expression in oxidative stress, suggesting that oxidative stress plays a role in 1-BP-induced neurotoxicity. To understand this role at the protein level, we exposed male F344 rats to 1-BP at 0, 400, or 1000 ppm for 8 h/day for 1 week or 4 weeks by inhalation and quantitated changes in hippocampal protein carbonyl using a protein carbonyl assay, two-dimensional gel electrophoresis (2-DE), immunoblotting, and matrix-assisted laser-desorption ionization time-of-flight mass spectrometry (MALDI-TOF-TOF/MS). Hippocampal reactive oxygen species and protein carbonyl were significantly increased, demonstrating 1-BP-associated induction of oxidative stress and protein damage. MALDI-TOF-TOF/MS identified 10 individual proteins with increased carbonyl modification (p < 0.05; fold-change ≥ 1.5). The identified proteins were involved in diverse biological processes including glycolysis, ATP production, tyrosine catabolism, GTP binding, guanine degradation, and neuronal metabolism of dopamine. Hippocampal triosephosphate isomerase (TPI) activity was significantly reduced and negatively correlated with TPI carbonylation (p < 0.001; r = 0.83). Advanced glycation end-product (AGE) levels were significantly elevated both in the hippocampus and plasma, and hippocampal AGEs correlated negatively with TPI activity (p < 0.001; r = 0.71). In conclusion, 1-BP-induced neurotoxicity in the rat hippocampus seems to involve oxidative damage of cellular proteins, decreased TPI activity, and elevated AGEs. -- Highlights: ► 1-BP increases hippocampal ROS levels and hippocampal and plasma protein carbonyls. ► 1-BP increases TPI carbonylation and decreases TPI activity in the hippocampus. ► 1-BP increases hippocampal and plasma AGE levels.

  14. Versatile ruthenium(II) dye towards blue-light emitter and dye-sensitizer for solar cells

    Science.gov (United States)

    Zanoni, Kassio P. S.; Amaral, Ronaldo C.; Murakami Iha, Neyde Y.; Abreu, Felipe D.; de Carvalho, Idalina M. M.

    2018-06-01

    A versatile Ru(II) complex bearing an anthracene moiety was synthesized in our search for suitable compounds towards efficient molecular devices. The new engineered dye, cis‑[Ru(dcbH2)(NCS)2(mbpy‑anth)] (dcbH2 = 2,2‧‑bipyridyl‑4,4‧‑dicarboxylic acid, mbpy‑anth = 4‑[N‑(2‑anthryl)carbamoyl]‑4‧‑methyl‑2,2‧‑bipyridine), exhibits a blueish emission in a vibronically structured spectrum ascribed to the fluorescence of a 1LCAnth (ligand centered) excited state in the anthracene and has a potential to be exploited in the fields of smart lighting and displays. This complex was also employed in dye-sensitized solar cells with fairly efficient solar energy conversion with the use of self-assembled TiO2 compact layers beneath the TiO2 mesoporous film to prevent meso‑TiO2/dye back reactions. Further photoelectrochemical investigations through incident photon-to-current efficiency and electrochemical impedance spectra showed that the all-nano-TiO2 compact layer acts as contact layers that increase the electron harvesting in the external circuit, enhancing efficiencies up to 50%.

  15. Enhanced microwave absorption in ZnO/carbonyl iron nano-composites by coating dielectric material

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Chang [School of Physics and Material Science, Anhui University, Hefei 230036 (China); Key Laboratory of Opto-electronic Information Acquisition and Manipulation Ministry of Education, Anhui University, Hefei 230039 (China); Fang Qingqing, E-mail: physfangqq@126.com [School of Physics and Material Science, Anhui University, Hefei 230036 (China) and Key Laboratory of Opto-electronic Information Acquisition and Manipulation Ministry of Education, Anhui University, Hefei 230039 (China); Yan Fangliang; Wang Weina; Wu Keyue; Liu Yanmei; Lv Qingrong; Zhang Hanming; Zhang Qiping; Li Jinguang; Ding Qiongqiong [School of Physics and Material Science, Anhui University, Hefei 230036 (China); Key Laboratory of Opto-electronic Information Acquisition and Manipulation Ministry of Education, Anhui University, Hefei 230039 (China)

    2012-05-15

    The microwave absorption properties of zinc oxide/carbonyl iron composite nanoparticles fabricated by high energy ball milling were studied at 0-20 GHz. Experiments showed that ZnO as a kind of dielectric material coating carbonyl iron particles made the bandwidth of reflection loss (RL)<-5 dB expanding to the low frequency, and enhanced absorption effect obviously. For a 3 mm thickness absorber of ZnO/carbonyl iron after 30 h milling, the values of RL<-5 dB and RL<-8 dB were obtained in the frequency range from 7.0 GHz to 17.8 GHz and from 9.8 dB to 14.9 dB, respectively, and its strongest RL peak was -29.34 dB at 13.59 GHz. The magnetic loss of carbonyl iron particles and the dielectric loss of ZnO particles were the main mechanisms of microwave absorption for the composites. - Highlights: Black-Right-Pointing-Pointer We fabricated zinc oxide/carbonyl iron composites by high energy ball milling. Black-Right-Pointing-Pointer ZnO dielectric property increased absorption effect and absorption bandwidth. Black-Right-Pointing-Pointer Absorbing frequence of composites is expanding to low frequency direction. Black-Right-Pointing-Pointer The craft of high energy ball milling is easy to realize commerce production.

  16. Enhanced microwave absorption in ZnO/carbonyl iron nano-composites by coating dielectric material

    International Nuclear Information System (INIS)

    Zhou Chang; Fang Qingqing; Yan Fangliang; Wang Weina; Wu Keyue; Liu Yanmei; Lv Qingrong; Zhang Hanming; Zhang Qiping; Li Jinguang; Ding Qiongqiong

    2012-01-01

    The microwave absorption properties of zinc oxide/carbonyl iron composite nanoparticles fabricated by high energy ball milling were studied at 0–20 GHz. Experiments showed that ZnO as a kind of dielectric material coating carbonyl iron particles made the bandwidth of reflection loss (RL)<−5 dB expanding to the low frequency, and enhanced absorption effect obviously. For a 3 mm thickness absorber of ZnO/carbonyl iron after 30 h milling, the values of RL<−5 dB and RL<−8 dB were obtained in the frequency range from 7.0 GHz to 17.8 GHz and from 9.8 dB to 14.9 dB, respectively, and its strongest RL peak was −29.34 dB at 13.59 GHz. The magnetic loss of carbonyl iron particles and the dielectric loss of ZnO particles were the main mechanisms of microwave absorption for the composites. - Highlights: ► We fabricated zinc oxide/carbonyl iron composites by high energy ball milling. ► ZnO dielectric property increased absorption effect and absorption bandwidth. ► Absorbing frequence of composites is expanding to low frequency direction. ► The craft of high energy ball milling is easy to realize commerce production.

  17. Catalytic reactions of synthesis gas. Part 2. Methanol carbonylation and homologation

    Energy Technology Data Exchange (ETDEWEB)

    Niemelae, M.

    1993-01-01

    The aim of the review is to evaluate the applicability of methanol hydrocarbonylation as a second test reaction to study the nondissociative activation of CO by heterogeneous rhodium and cobalt catalysts. The main emphasis in methanol (hydro)carbonylation chemistry has been on homogeneous reactions. These systems have been seen advantageous in selectivity, activity and ease of modification. The heterogenization attempts have been carried out to obtain easier separation of the catalyst and the product. The activity of cobalt, rhodium and other metals supported on different materials have been studied in heterogeneous methanol (hydro)carbonylation. The observed activities have been considerably influenced by the support. The most effective catalyst support has been activated carbon. Good carbonylation activities and selectivities have also been observed in conjunction with zeolite supports. The literature study indicates that the typical experimental conditions of methanol (hydro)carbonylation do not exceed the constructional and operational limits of the available reactor system, i.e. 500 C and 50 bar. The reaction is suitable for testing Co and Rh precursors, since both cobalt and rhodium compounds have shown carbonylation activity.

  18. Enhanced antioxidation and microwave absorbing properties of SiO2-coated flaky carbonyl iron particles

    Science.gov (United States)

    Zhou, Yingying; Xie, Hui; Zhou, Wancheng; Ren, Zhaowen

    2018-01-01

    SiO2 was successfully coated on the surface of flaky carbonyl iron particles using a chemical bath deposition method in the presence of 3-aminopropyl triethoxysilane (APTES). The morphologies, composition, valence states of elements, as well as antioxidation and electromagnetic properties of the samples were characterized by scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray photoelectron spectroscopy (XPS), thermogravimetric (TG) and microwave network analyzer. TG curve shows the obvious weight gain of carbonyl iron was deferred to 360 °C after SiO2-coated, which can be ascribed to the exits of SiO2 overlayer. Compared with the raw carbonyl iron, SiO2-coated sample shows good wave absorption performance due to its impedance matching. The electromagnetic properties of raw and SiO2-coated carbonyl iron particles were characterized in X band before and after heat treatment at 250 °C for 10 h. It was established that SiO2-coated carbonyl iron demonstrate good thermal stability, indicating SiO2-coating is useful in the usage of microwave absorbers operating at temperature up to 250 °C.

  19. Proteomic evaluation of myofibrillar carbonylation in chilled fish mince and its inhibition by catechin.

    Science.gov (United States)

    Pazos, Manuel; Maestre, Rodrigo; Gallardo, José M; Medina, Isabel

    2013-01-01

    The present study investigates the susceptibility of individual myofibrillar proteins from mackerel (Scomber scombrus) mince to undergo carbonylation reactions during chilled storage, and the antioxidant capacity of (+)-catechin to prevent oxidative processes of proteins. The carbonylation of each particular protein was quantified by combining the labelling of protein carbonyls by fluorescein-5-thiosemicarbazide (FTSC) with 1-D or 2-D gel electrophoresis. Alpha skeletal actin, glycogen phosphorylase, unnamed protein product (UNP) similar to enolase, pyruvate kinase, isoforms of creatine kinase, aldolase A and an isoform of glyceraldehyde 3-phosphate dehydrogenase (G3PDH) showed elevated oxidation in chilled non-supplemented mince. Myosin heavy chain (MHC) was not carbonylated in chilled muscle, but an extensive MHC degradation was observed in those samples. The supplementation of catechin reduced protein oxidation and lipid oxidation in a concentration-dependent manner: control>25>100≈200ppm. Therefore, the highest catechin concentrations (100 and 200ppm) exhibited the strongest antioxidant activity. Catechin (200ppm) reduced significantly carbonylation of protein spots identified as glycogen phosphorylase, pyruvate kinase muscle isozyme, isoforms of creatine kinase. Conversely, catechin was ineffective to inhibit the oxidation of actin and UNP similar to enolase. These results draw attention to the inefficiency of catechin to prevent actin oxidation, in contrast to the extremely high efficiency of catechin in inhibiting oxidation of lipids and other proteins. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Electromagnetic absorbing property of the flaky carbonyl iron particles by chemical corrosion process

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Dianliang, E-mail: 272895980@qq.com [College of Aeronautical Engineering, Jilin Institute of Chemical Technology, Jilin 132022 (China); Liu, Ting; Zhou, Li [College of Aeronautical Engineering, Jilin Institute of Chemical Technology, Jilin 132022 (China); Xu, Yonggang [Science and Technology on Electromagnetic Scattering Laboratory, Shanghai 200438 (China)

    2016-12-01

    The flaky carbonyl iron particles (CIPs) were prepared using a milling process at the first step, then the chemical corrosion process was done to optimize the particle shape. The particle morphology was characterized by the scanning electron microscopy, the static magnetic property was evaluated on a vibrating sample magnetometer and X-ray diffraction (XRD) patterns were done to analyze the particle crystal grain structure. The complex permittivity and permeability were measured using a vector network analyzer in the frequency range of 2–18 GHz and the reflection loss (RL) was calculated. The results showed that the saturation magnetization value of the CIPs decreased as the CIPs was corroded to the small flakes in chemical corrosion process. The diffraction peaks of the single α-Fe existed in the XRD pattern of CIPs, and the characteristic peaks was more obvious and the intensity of the diffraction pattern was lower by corrosion. The permittivity and the permeability of the corroded milling CIPs was a little larger than the milling CIPs, it was due to the larger aspect ratio based on the fitting calculation process. At thickness 0.6 mm and 0.8 mm, the corroded milling CIPs composite had the better absorbing property than the other two samples. The frequency band (RL<−5 dB) could be widened to 8.96–18 GHz at 0.6 mm and 5.92–18 GHz at 0.8 mm, and RL less than −8 dB began to exist in 8.96–14.72 GHz at 0.8 mm. - Graphical abstract: The property of absorber using corrosion process could be enhanced. - Highlights: • The chemical corrosion process was done to optimize the particle shape. • The permittivity and permeability of corroded milling CIPs increased. • The aspect ratio of flaky CIPs increased in the corrosion process. • The corroded milling CIPs composite had the better absorbing property.

  1. Influence of the Dielectric Medium on the Carbonyl Infrared Absorption Peak of Acetylferrocene

    Directory of Open Access Journals (Sweden)

    F. López-Linares

    2005-02-01

    Full Text Available The solvent effect on the position of the carbonyl vibrational stretching ofacetylferrocene in aprotic media was studied in this work. The solvent-induced shifts in thisorganometallic compound were interpreted in terms of the alternative reaction field model(SCRF-MO proposed by Kolling. In contrast to the established trends for carbonyl groupsin organic systems, the results suggest that the continuum models for the reaction field arenot adequate and that the influence of dipolarity-polarizability described by aninhomogeneous coupling function θ (ε L(n 2 that assumes optical dielectric saturation isresponsible for the carbonyl band shift and, there is empirical evidence that the effect offield-induced intermolecular interaction on band shift, interpreted in terms of the van derWaals forces from the solvent, have a important contribution to this phenomena.

  2. Coal and biomass-based chemicals via carbonylation, hydroformylation and homologation reactions

    Energy Technology Data Exchange (ETDEWEB)

    Sunavala, P.D.; Raghunath, B.

    The paper emphasizes the importance of carbonylation, hydroformylation and homologation reactions in the manufacture of organic chemicals (such as acetic acid, acetic anhydride, cellulose acetate, vinyl acetate monomer, aliphatic amines, isocyanates, methanol, ethanol, n-butanol, ethylene glycol, acrylic acid, etc.) from coal and biomass feedstocks. Topics covered are: synthesis of acetic acid; manufacture of acetic anhydride; synthesis of vinyl acetate monomer by carbonylation; synthesis of aliphatic amines by hydroformylation; synthesis of organic diisocyanates; ethanol synthesis by homologation of methanol; synthesis of ethylene glycol via hydroformylation of formaldehyde; synthesis of n- butanol and n-butyraldehyde by propylene formylation; synthesis of acrylic acid; homologation reaction of carboxylic acid esters with ruthenium catalysts; and synthesis of phenyl isocyanate from nitrobenzene by reductive carbonylation. 26 refs.

  3. Effect of carbonyl iron particles composition on the physical characteristics of MR grease

    Energy Technology Data Exchange (ETDEWEB)

    Mohamad, Norzilawati, E-mail: mnorzilawati@gmail.com; Mazlan, Saiful Amri, E-mail: amri.kl@utm.my [Vehicle System Engineering, Malaysia – Japan International Institute of Technology, Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra (Jalan Semarak), Kuala Lumpur, 54000 (Malaysia); Ubaidillah, E-mail: ubaidillah@uns.ac.id [Vehicle System Engineering, Malaysia – Japan International Institute of Technology, Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra (Jalan Semarak), Kuala Lumpur, 54000 (Malaysia); Mechanical Engineering Department, Faculty of Engineering, Universitas Sebelas Maret, Jl. Ir. Sutami 36A, Kentingan, Surakarta, 57126, Central Java, Surakarta (Indonesia)

    2016-03-29

    Magnetorheological (MR) grease is an extension of the study of magnetorheological materials. The MR grease can help to reduce the particles sedimentation problem occurred in the MR fluids. Within this study, an effort has been taken to investigate the effect of different weight compositions of carbonyl iron particles on the physical and chemical characteristics of the MR grease under off-state condition (no magnetic field). The MR grease is prepared by mixing carbonyl iron particles having a size range of 1 to 10 µm with commercial NPC Highrex HD-3 grease. Characterizations of MR grease are investigated using Vibrating Sample Magnetometer (VSM), Environmental Scanning Electron Microscopy (ESEM), Differential Scanning Calorimeter (DSC) and rheometer. The dependency of carbonyl iron particles weight towards the magnetic properties of MR grease and other characterizations are investigated.

  4. First application of supported ionic liquid phase (SILP) catalysis for continuous methanol carbonylation

    DEFF Research Database (Denmark)

    Riisager, Anders; Jørgensen, Betina; Wasserscheid, Peter

    2006-01-01

    A solid, silica-supported ionic liquid phase (SILP) rhodium iodide Monsanto-type catalyst system, [BMIM][Rh(CO)(2)I-2]-[BMIM]I -SiO2, exhibits excellent activity and selectivity towards acetyl products in fixed-bed, continuous gas-phase methanol carbonylation.......A solid, silica-supported ionic liquid phase (SILP) rhodium iodide Monsanto-type catalyst system, [BMIM][Rh(CO)(2)I-2]-[BMIM]I -SiO2, exhibits excellent activity and selectivity towards acetyl products in fixed-bed, continuous gas-phase methanol carbonylation....

  5. Reaction of acid esters of methylenebis(phosphonous acid) with carbonyl compounds

    International Nuclear Information System (INIS)

    Novikova, Z.S.; Odinets, I.L.; Lutsenko, I.F.

    1987-01-01

    The reaction of methylenebis(phosphonites) containing two hydrophosphoryl groupings with aliphatic and aromatic aldehydes and ketones in the presence of alkali metal fluorides leads to methylenebis(α-hydroxyalkylphosphinates). The reaction of methylenebis(phosphonites) containing one hydrophosphoryl groupings with carbonyl compounds in the presence of alkali metal fluorides proceeds with the formation of a new type of heterocyclic phosphorus compound, viz., 1,2λ 3 ,4λ 5 -oxadiphospholanes. The reaction of acid esters of methylenebis(phosphonous) acid with carbonyl compounds in the presence of alkali metal alkoxides or a tertiary amine is accompanied by phosphinate-phosphonate rearrangement of the intermediately formed α-hydroxylalkylphosphinates

  6. Impaired cardiac SIRT1 activity by carbonyl stress contributes to aging-related ischemic intolerance.

    Directory of Open Access Journals (Sweden)

    Chunhu Gu

    Full Text Available Reactive aldehydes can initiate protein oxidative damage which may contribute to heart senescence. Sirtuin 1 (SIRT1 is considered to be a potential interventional target for I/R injury management in the elderly. We hypothesized that aldehyde mediated carbonyl stress increases susceptibility of aged hearts to ischemia/reperfusion (I/R injury, and elucidate the underlying mechanisms with a focus on SIRT1. Male C57BL/6 young (4-6 mo and aged (22-24 mo mice were subjected to myocardial I/R. Cardiac aldehyde dehydrogenase (ALDH2, SIRT1 activity and protein carbonyls were assessed. Our data revealed that aged heart exhibited increased endogenous aldehyde/carbonyl stress due to impaired ALDH2 activity concomitant with blunted SIRT1 activity (P<0.05. Exogenous toxic aldehydes (4-HNE exposure in isolated cardiomyocyte verified that aldehyde-induced carbonyl modification on SIRT1 impaired SIRT1 activity leading to worse hypoxia/reoxygenation (H/R injury, which could all be rescued by Alda-1 (ALDH2 activator (all P<0.05. However, SIRT1 inhibitor blocked the protective effect of Alda-1 on H/R cardiomyocyte. Interestingly, myocardial I/R leads to higher carbonylation but lower activity of SIRT1 in aged hearts than that seen in young hearts (P<0.05. The application of Alda-1 significantly reduced the carbonylation on SIRT1 and markedly improved the tolerance to in vivo I/R injury in aged hearts, but failed to protect Sirt1(+/- knockout mice against myocardial I/R injury. This was verified by Alda-1 treatment improved postischemic contractile function recovery in ex vivo perfused aged but not in Sirt1(+/- hearts. Thus, aldehyde/carbonyl stress is accelerated in aging heart. These results provide a new insight that impaired cardiac SIRT1 activity by carbonyl stress plays a critical role in the increased susceptibility of aged heart to I/R injury. ALDH2 activation can restore this aging-related myocardial ischemic intolerance.

  7. Nicotine and Carbonyl Emissions From Popular Electronic Cigarette Products: Correlation to Liquid Composition and Design Characteristics.

    Science.gov (United States)

    El-Hellani, Ahmad; Salman, Rola; El-Hage, Rachel; Talih, Soha; Malek, Nathalie; Baalbaki, Rima; Karaoghlanian, Nareg; Nakkash, Rima; Shihadeh, Alan; Saliba, Najat A

    2018-01-05

    Available in hundreds of device designs and thousands of flavors, electronic cigarette (ECIG) may have differing toxicant emission characteristics. This study assesses nicotine and carbonyl yields in the most popular brands in the U.S. market. These products included disposable, prefilled cartridge, and tank-based ECIGs. Twenty-seven ECIG products of 10 brands were procured and their power outputs were measured. The e-liquids were characterized for pH, nicotine concentration, propylene glycol/vegetable glycerin (PG/VG) ratio, and water content. Aerosols were generated using a puffing machine and nicotine and carbonyls were, respectively, quantified using gas chromatograph and high-performance liquid chromatography. A multiregression model was used to interpret the data. Nicotine yields varied from 0.27 to 2.91 mg/15 puffs, a range corresponding to the nicotine yield of less than 1 to more than 3 combustible cigarettes. Nicotine yield was highly correlated with ECIG type and brand, liquid nicotine concentration, and PG/VG ratio, and to a lower significance with electrical power, but not with pH and water content. Carbonyls, including the carcinogen formaldehyde, were detected in all ECIG aerosols, with total carbonyl concentrations ranging from 3.72 to 48.85 µg/15 puffs. Unlike nicotine, carbonyl concentrations were mainly correlated with power. In 15 puffs, some ECIG devices emit nicotine quantities that exceed those of tobacco cigarettes. Nicotine emissions vary widely across products but carbonyl emissions showed little variations. In spite of that ECIG users are exposed to toxicologically significant levels of carbonyl compounds, especially formaldehyde. Regression analysis showed the importance of design and e-liquid characteristics as determinants of nicotine and carbonyl emissions. Periodic surveying of characteristics of ECIG products available in the marketplace is valuable for understanding population-wide changes in ECIG use patterns over time. © The

  8. Dithioacetals as an Entry to Titanium-Alkylidene Chemistry: A New and Efficient Carbonyl Olefination.

    Science.gov (United States)

    Breit, Bernhard

    1998-03-02

    Wittig, Horner-Wadsworth-Emmons, Julia-Lythgoe, Tebbe, Grubbs, and Petasis-when it comes to carbonyl olefinations, these names are familiar to all chemistry students. In the future, the name Takeda will probably have to be added to this list. His recent work on the formation of titanium-alkylidene species from dithioacetals has provided organic chemists with a remarkable method for carbonyl olefination that is generally applicable under neutral to Lewis acidic conditions. © 1998 WILEY-VCH Verlag GmbH, Weinheim, Fed. Rep. of Germany.

  9. (alpha-Diimine)tricarbonylhalorhenium complexes: the oxidation side

    Czech Academy of Sciences Publication Activity Database

    Drozdz, A.; Bubrin, M.; Fiedler, Jan; Záliš, Stanislav; Kaim, W.

    2012-01-01

    Roč. 41, č. 3 (2012), s. 1013-1019 ISSN 1477-9226 R&D Projects: GA MŠk LD11086; GA MŠk(CZ) ME10124 Institutional research plan: CEZ:AV0Z40400503 Keywords : (alpha-Diimine)tricarbonylhalorhenium complexes * electrochemistry * metal carbonyl complexes Subject RIV: CG - Electrochemistry Impact factor: 3.806, year: 2012

  10. Ketene as a Reaction Intermediate in the Carbonylation of Dimethyl Ether to Methyl Acetate over Mordenite

    DEFF Research Database (Denmark)

    Rasmussen, Dominik Bjørn; Christensen, Jakob Munkholt; Temel, Burcin

    2015-01-01

    Unprecedented insight into the carbonylation of dimethyl ether over Mordenite is provided through the identification of ketene (CH2CO) as a reaction intermediate. The formation of ketene is predicted by detailed DFT calculations and verified experimentally by the observation of doubly deuterated ...

  11. Determination of protein carbonyls in plasma, cell extracts, tissue homogenates, isolated proteins

    DEFF Research Database (Denmark)

    Weber, Daniela; Davies, Michael J.; Grune, Tilman

    2015-01-01

    Protein oxidation is involved in regulatory physiological events as well as in damage to tissues and is thought to play a key role in the pathophysiology of diseases and in the aging process. Protein-bound carbonyls represent a marker of global protein oxidation, as they are generated by multiple...

  12. Formation and emissions of carbonyls during and following gas-phase ozonation of indoor materials

    DEFF Research Database (Denmark)

    Poppendieck, D.G.; Hubbard, H.F.; Weschler, Charles J.

    2007-01-01

    at concentrations of 1000 ppm in the inlet stream of experimental chambers. Fifteen target carbonyls were selected and measured as building ozonation by-products (BOBPs). During the 36 h that include the 16 h ozonation and 20 h persistence phase, the total BOBP mass released from flooring and wall coverings ranged...

  13. First application of supported ionic liquid phase (SILP) catalysis for continuous methanol carbonylation.

    Science.gov (United States)

    Riisager, Anders; Jørgensen, Betina; Wasserscheid, Peter; Fehrmann, Rasmus

    2006-03-07

    A solid, silica-supported ionic liquid phase (SILP) rhodium iodide Monsanto-type catalyst system, [BMIM][Rh(CO)2I2]-[BMIM]I-SiO2, exhibits excellent activity and selectivity towards acetyl products in fixed-bed, continuous gas-phase methanol carbonylation.

  14. Unsuitability of using the DNPH-coated solid sorbent cartridge for determination of airborne unsaturated carbonyls

    Science.gov (United States)

    Ho, Steven Sai Hang; Ho, K. F.; Liu, W. D.; Lee, S. C.; Dai, W. T.; Cao, J. J.; Ip, H. S. S.

    2011-01-01

    Measurements of aldehydes and ketones are typically conducted by derivatization using sorbent cartridges coated with 2,4-dinitrophenylhydrazine (DNPH). The collected samples are eluted with acetonitrile and analyzed by high-pressure liquid chromatography coupled with an ultra-violet detector (HPLC/UV). This paper intends to examine artifacts about its suitability in identification of unsaturated carbonyls. Kinetic tests for acrolein, crotonaldehyde, methacrolein and methyl vinyl ketone (MVK) showed formations of carbonyl-DNP-hydrazone during sampling, which could further react with DNPH, resulting in undesired UV absorption products [e.g., carbonyl-DNP-hydrazone-DNPH (dimer) and 2(carbonyl-DNP-hydrazone)-DNPH (trimer)]. The dimerization and trimerization occurred for acrolein and MVK whereas only dimerization for crotonaldehyde and methacrolein. The polymerization products undoubtedly affect the integrity of the chromatogram, leading to misidentification and inaccurate quantification. Whether precautions taken during sampling and/or sample treatment could avoid or minimize this artifact has not been thoughtfully investigated. More often, such artifacts are usually overlooked by scientists when the data are reported.

  15. Antioxidative potential of Perna viridis and its protective role against ROS induced lipidperoxidation and protein carbonyl

    Digital Repository Service at National Institute of Oceanography (India)

    Jena, K.B.; Jagtap, T.G.; Verlecar, X.N.

    ) such as hydrogen peroxide (H2O2) and hydroxyl radical (OH•), and inhibition of lipid peroxidation (LPX) and protein carbonyl (PC). The scavenging activity of DPPH radical, H sub(2) O sub(2) and OH• radicals increased in dose dependent manner. The reducing power...

  16. Magnetically Recoverable Supported Ruthenium Catalyst for Hydrogenation of Alkynes and Transfer Hydrogenation of Carbonyl Compounds

    Science.gov (United States)

    A ruthenium (Ru) catalyst supported on magnetic nanoparticles (NiFe2O4) has been successfully synthesized and used for hydrogenation of alkynes at room temperature as well as transfer hydrogenation of a number of carbonyl compounds under microwave irradiation conditions. The cata...

  17. [1,3-Bis(diphenyl-phosphino)pentane-κP,P']tetra-carbonyl-chromium(0).

    Science.gov (United States)

    Shawkataly, Omar Bin; Thangadurai, Daniel T; Pankhi, Mohd Aslam A; Shahinoor Dulal Islam, S M; Fun, Hoong-Kun

    2009-02-04

    In the title compound, [Cr(C(29)H(30)P(2))(CO)(4)], the Cr atom is octa-hedrally coordinated by four carbonyl ligands and one bidentate phosphine ligand, which is bounded as a chelate in a cis position. The average Cr-P and Cr-C bond lengths are 2.377 and 1.865 Å, respectively.

  18. Mechanism of stimulation of endogenous fermentation in yeast by carbonyl cyanide m-chlorophenylhydrazone

    NARCIS (Netherlands)

    Noshiro, A.; Purwin, C.; Laux, M.; Nicolaij, K.; Scheffers, W.A.; Holzer, H.

    1987-01-01

    Addition of the uncoupler and protonophore carbonyl cyanide m-chlorophenylhydrazone (CCCP) to starved yeast cells starts endogenous alcoholic fermentation lasting about 20 min. Hexose 6-phosphates, fructose 2,6-bisphosphate, and pyruvate accumulate in less than 2 min after addition of CCCP from

  19. Efficient Conversion of Oximes to the Corresponding Carbonyl Compounds with Tetrabutylammonium Chromate under Aprotic Conditions

    International Nuclear Information System (INIS)

    Pourali, Ali Reza; Goli, Arezou

    2006-01-01

    The solubility in several solvents, mildness, simple work-up and absence of side reactions provide advantages of using TBAC in deoximation reactions. This is an efficient and selective method for homogeneous deoximation of structurally different compounds under the moderately acidic and aprotic conditions in high yields. Regeneration of ketones and aldehydes from their oximes has assumed added importance since the discovery of the Barton reaction in which oximes are produced at non-activated hydrocarbon sites. Also, their synthesis from non-carbonyl compounds, such as by nitrosation of an active methylene group, nitrosation of an α-halo carbonyl compound and condensation of a nitro-alkene with an aldehyde provides a valid alternative pathway to carbonyl compounds. Therefore, there has been a continued interest in the effective regeneration of carbonyl compounds from the corresponding oximes especially under mild conditions. Oxidative and reductive methods have been found to show advantages over the classical hydrolytic methods. Although many oxidizing agents have been used, only a limited number of methods are efficient because of the low solubility of these metallic reagents in most organic solvents

  20. Iron Dextran treatment does not induce serum protein carbonyls in the newborn pig

    Science.gov (United States)

    Oxidation of serum proteins can lead to carbonyl formation which alters their function and is often associated with stress-related diseases. Since it is recommended that all pigs reared in modern production facilities be given supplemental iron at birth to prevent anemia, and metals can catalyze th...

  1. Weak carbonyl-methyl intermolecular interactions in acetone clusters explored by IR plus VUV spectroscopy

    International Nuclear Information System (INIS)

    Guan, Jiwen; Hu, Yongjun; Xie, Min; Bernstein, Elliot R.

    2012-01-01

    Highlights: ► The carbonyl overtone of acetone clusters is observed by IR-VUV spectroscopy. ► Acetone molecules in the dimer are stacked with an antiparallel way. ► The structure of the acetone trimer and the tetramer are the cyclic structures. ► The carbonyl groups would interact with the methyl groups in acetone clusters. ► These weak interactions are further confirmed by H/D substitution experiment. -- Abstract: Size-selected IR–VUV spectroscopy is employed to detect vibrational characteristics in the region 2850 ∼ 3550 cm −1 of neutral acetone and its clusters (CH 3 COCH 3 ) n (n = 1–4). Features around 3440 cm −1 in the spectra of acetone monomer and its clusters are assigned to the carbonyl stretch (CO) overtone. These features red-shift from 3455 to 3433 cm −1 as the size of the clusters increases from the monomer to the tetramer. Based on calculations, the experimental IR spectra in the C=O overtone region suggest that the dominant structures for the acetone trimer and tetramer should be cyclic in the supersonic expansion sample. This study also suggests that the carbonyl groups interact with the methyl groups in the acetone clusters. These weak interactions are further confirmed by the use of deuterium substitution.

  2. Effect of carotenoid structure on excited-state dynamics of carbonyl carotenoids

    Czech Academy of Sciences Publication Activity Database

    Chábera, P.; Fuciman, M.; Hříbek, P.; Polívka, Tomáš

    2009-01-01

    Roč. 11, - (2009), s. 8795-8703 ISSN 1463-9076 R&D Projects: GA AV ČR IAA608170604 Institutional research plan: CEZ:AV0Z50510513 Keywords : excited-state dynamics * carbonyl carotenoids * femtosecond spectroscopy Subject RIV: BO - Biophysics Impact factor: 4.116, year: 2009

  3. Proteomic and carbonylation profile analysis of rat skeletal muscles following acute swimming exercise.

    Directory of Open Access Journals (Sweden)

    Francesca Magherini

    Full Text Available Previous studies by us and other groups characterized protein expression variation following long-term moderate training, whereas the effects of single bursts of exercise are less known. Making use of a proteomic approach, we investigated the effects of acute swimming exercise (ASE on protein expression and carbonylation patterns in two hind limb muscles: the Extensor Digitorum Longus (EDL and the Soleus, mostly composed of fast-twitch and slow-twitch fibres, respectively. Carbonylation is one of the most common oxidative modifications of proteins and a marker of oxidative stress. In fact, several studies suggest that physical activity and the consequent increase in oxygen consumption can lead to increase in reactive oxygen and nitrogen species (RONS production, hence the interest in examining the impact of RONS on skeletal muscle proteins following ASE. Results indicate that protein expression is unaffected by ASE in both muscle types. Unexpectedly, the protein carbonylation level was reduced following ASE. In particular, the analysis found 31 and 5 spots, in Soleus and EDL muscles respectively, whose carbonylation is reduced after ASE. Lipid peroxidation levels in Soleus were markedly reduced as well. Most of the decarbonylated proteins are involved either in the regulation of muscle contractions or in the regulation of energy metabolism. A number of hypotheses may be advanced to account for such results, which will be addressed in future studies.

  4. Interaction between alkaline earth cations and oxo-ligands. DFT study of the affinity of the Ca2+ cation for carbonyl ligands.

    Science.gov (United States)

    da Costa, Leonardo Moreira; Carneiro, José Walkimar de Mesquita; Romeiro, Gilberto Alves; Paes, Lilian Weitzel Coelho

    2011-02-01

    The affinity of the Ca(2+) ion for a set of substituted carbonyl ligands was analyzed with both the DFT (B3LYP/6-31+G(d)) and semi-empirical (PM6) methods. Two types of ligands were studied: a set of monosubstituted [O=CH(R)] and a set of disubstituted ligands [O=C(R)(2)] (R=H, F, Cl, Br, OH, OCH(3), CH(3), CN, NH(2) and NO(2)), with R either directly bound to the carbonyl carbon atom or to the para position of a phenyl ring. The interaction energy was calculated to quantify the affinity of the Ca(2+) cation for the ligands. Geometric and electronic parameters were correlated with the intensity of the metal-ligand interaction. The electronic nature of the substituent is the main parameter that determines the interaction energy. Donor groups make the interaction energy more negative (stabilizing the complex formed), while acceptor groups make the interaction energy less negative (destabilizing the complex formed).

  5. Protein carbonyl content: a novel biomarker for aging in HIV/AIDS patients.

    Science.gov (United States)

    Kolgiri, Vaishali; Patil, Vinayak Wamanrao

    The major complications of "treated" Human Immunodeficiency Virus (HIV) infection are cardiovascular disease, malignancy, renal disease, liver disease, bone disease, and perhaps neurological complications, which are phenomena of the normal aging process occurring at an earlier age in the HIV-infected population. The present study is aimed to explore protein carbonyl content as a biomarker for detecting oxidative DNA damage induced ART toxicity and/or accelerated aging in HIV/AIDS patients. To investigate the potential of carbonyl content as a biomarker for detecting oxidative Deoxyribonucleic acid (DNA) damage induced Antiretroviral Theraphy (ART) toxicity and/or accelerated aging in HIV/AIDS patients. In this case-control study a total 600 subjects were included. All subjects were randomly selected and grouped as HIV-negative (control group) (n=300), HIV-infected ART naive (n=100), HIV-infected on first line ART (n=100), and HIV-infected on second line ART (n=100). Seronegative control subjects were age- and sex-matched with the ART naive patients and the two other groups. Carbonyl protein was determined by the method described in Levine et al. DNA damage marker 8-OH-dG was determined using 8-hydroxy-2-deoxy Guanosine StressXpress ELA Kit by StressMarq Biosciences. Protein carbonyl content levels and oxidative DNA damage were significantly higher (paging in HIV/AIDS patients. Larger studies are warranted to elucidate the role of carbonyl content as a biomarker for premature aging in HIV/AIDS patients. Copyright © 2016 Sociedade Brasileira de Infectologia. Published by Elsevier Editora Ltda. All rights reserved.

  6. Inorganic heterocycles with two manganes or rhenium carbonyl units

    International Nuclear Information System (INIS)

    Kuellmer, V.; Vahrenkamp, H.

    1977-01-01

    From the reactive complexes [(CO) 4 M-E-Sn(CH 3 ) 3 ] 2 (M = Mn,Re; E = S,Se) with (CH 3 ) 2 PCl via the non-isolable four-membered ring intermediates [(CO) 4 M-E-P(CH 3 ) 2 ] 2 the six-membered heterocycles[-(CO) 4 M-P(CH 3 ) 2 -E-] 2 are formed. By use of (CH 3 ) 2 AsCl both the four-membered ring intermediates and the six-membered ring products can be isolated. The six-membered heterocycles can be opened by trimethylphosphine. (orig./HK) [de

  7. Two-step milling on the carbonyl iron particles and optimizing on the composite absorption

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yonggang, E-mail: xuyonggang221@163.com [Science and Technology on Electromagnetic Scattering Laboratory, Shanghai 200438 (China); Yuan, Liming; Wang, Xiaobing [Science and Technology on Electromagnetic Scattering Laboratory, Shanghai 200438 (China); Zhang, Deyuan [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, School of Mechanical Engineering and Automation, Beihang University, Beijing 100191 (China)

    2016-08-15

    The flaky carbonyl iron particles (CIPs) were prepared using a two-step milling process. The surface morphology was characterized by the scanning electron microscopy, the static magnetic property was evaluated on a vibrating sample magnetometer and X-ray diffraction (XRD) patterns were done to analyze the particle crystal grain structure. The complex permittivity and permeability were measured using a vector network analyzer in the frequency range of 2–18 GHz. Then Hermite interpolation based on the calculated scattering parameters of the tested composite was used to derive the permittivity and permeability of the composite with random volume content. The results showed that the saturation magnetization value of the flaky CIPs decreased as the CIPs was changed to the flakes by high and low speeding milling. The diffraction peaks of the single α-Fe existed in the XRD pattern of CIPs, and the characteristic peaks was broad and the intensity of the diffraction pattern was lower as the high-speeding milling time increased. The sample H2L20 had the largest particle size, the average diameter was 8.64 μm, the thickness was 0.59 μm according to the fitted aspect ratio 14.65. The derived permittivity and permeability using the Hermite interpolation was accurate compared with the tested result, the deviation was about 0.39 + j0.45 and 2.5 + j0.51. Finally, the genetic algorithm was used to optimize the thickness of the CIPs composite of a wide absorbing band of 8–18 GHz. The optimized reflection loss (RL) result showed that the absorbing composites with thickness 1.47 mm had an excellent absorbing property (RL < −10 dB) in 8–18 GHz. - Graphical abstract: The property of absorber added two speeding milling CIPs could be enhanced using the genetic algorithm. - Highlights: • Flaky CIPs were prepared using a two-step milling process. • The permeability increased during the low speeding milling. • The aspect ratio of flaky CIPs increased in the optimized process

  8. Synthesis of cationic diphosphine ruthenium complexes with nido-dicarbaundecaborate anions. Molecular structure of [RuCl(dppe)2]+[7,8-nido-C2B9H12]-

    International Nuclear Information System (INIS)

    Cheredilin, D.N.; Dolgushin, F.M.; Balagurova, E.V.; Godovikov, I.A.; Chizhevskij, I.T.

    2004-01-01

    Five new diphosphine ruthenium(II) complexes with nido-dicarbaundecaborate anions were synthesized. The composition and structure of the complexes were confirmed by data of 1 H, 31 P{ 1 H} NMR and elementary analysis. The crystal and molecular structure of solvated complex [RuCl(dppe) 2 + [7,8-nido-C 2 B 9 H 12 ] - ·CH 2 Cl 2 was ascertained by the method of X-ray diffraction analysis. It is shown that coordination sphere of ruthenium atom in the complex cation is a distorted trigonal bipyramid. The distances from ruthenium atom to phosphorus atoms are 2.398(1) and 2.391(1) A, while the angle P-Ru-P equals 175.85(5) Deg [ru

  9. Characterization of hydrocarbons, halocarbons and carbonyls in the atmosphere of Hong Kong.

    Science.gov (United States)

    Guo, H; Lee, S C; Louie, P K K; Ho, K F

    2004-12-01

    Ambient air quality measurements of 156 species including 39 alkanes, 32 alkenes, 2 alkynes, 24 aromatic hydrocarbons, 43 halocarbons and 16 carbonyls, were carried out for 120 air samples collected at two sampling stations (CW and TW) in 2001 throughout Hong Kong. Spatial variations of volatile organic compounds (VOCs) in the atmosphere were investigated. Levels of most alkanes and alkenes at TW site were higher than that at the CW site, while the BTEX concentrations at the two sites were close. The BTEX ratios at CW and TW were 1.6:10.1:1.0:1.6 and 2.1:10.8:1.0:2.0, respectively. For major halogenated hydrocarbons, the mean concentrations of chloromethane, CFCs 12 and 22 did not show spatial variations at the two sites. However, site-specific differences were observed for trichloroethene and tetrachloroethene. Furthermore, there were no significant differences for carbonyls such as formaldehyde, acetaldehyde and acetone between the two sites. The levels of selected hydrocarbons in winter were 1-5 times that in summer. There were no common seasonal trends for carbonyls in Hong Kong. The ambient level of formaldehyde, the most abundant carbonyl, was higher in summer. However, levels of acetaldehyde, acetone and benzaldehyde in winter were 1.6-3.8 times that in summer. The levels of CFCs 11 and 12, and chloromethane in summer were higher than that in winter. Strong correlation of most hydrocarbons with propene and n-butane suggested that the primary contributors of hydrocarbons were vehicular emissions in Hong Kong. In addition, gasoline evaporation, use of solvents, leakage of liquefied petroleum gas (LPG), natural gas leakage and other industrial emissions, and even biogenic emissions affected the ambient levels of hydrocarbons. The sources of halocarbons were mainly materials used in industrial processes and as solvents. Correlation analysis suggested that photochemical reactions made significant contributions to the ambient levels of carbonyls in summer whereas

  10. Synthesis of silyl iron hydride via Si-H activation and its dual catalytic application in the hydrosilylation of carbonyl compounds and dehydration of benzamides.

    Science.gov (United States)

    Ren, Shishuai; Xie, Shangqing; Zheng, Tingting; Wang, Yangyang; Xu, Shilu; Xue, Benjing; Li, Xiaoyan; Sun, Hongjian; Fuhr, Olaf; Fenske, Dieter

    2018-03-28

    The hydrido silyl iron complex (o-Ph 2 PC 6 H 4 SiMe 2 )Fe(PMe 3 ) 3 H (2) was obtained via the activation of the Si-H bond of the bidentate silyl ligand o-Ph 2 P(C 6 H 4 )SiMe 2 H (1) by Fe(PMe 3 ) 4 . 2 showed good to excellent catalytic activity in both the reduction of aldehydes/ketones and the dehydration of benzamide. In addition, with complex 2 as a catalyst, α,β-unsaturated carbonyls could be selectively reduced to the corresponding α,β-unsaturated alcohols. The mechanisms of the formation of 2 and the catalytic dehydration process are proposed and partly experimentally verified.

  11. Towards the Development of Functionalized PolypyridineLigands for Ru(II Complexes as Photosensitizers inDye-Sensitized Solar Cells (DSSCs

    Directory of Open Access Journals (Sweden)

    Adewale O. Adeloye

    2014-08-01

    Full Text Available A number of novel ruthenium(II polypyridine complexes have been designedand synthesized for use as photosensitizers in dye-sensitized solar cells (DSSCs due totheir rich photophysical properties such as intense absorption, long-lived lifetimes, highemission quantum yields and unique redox characteristics. Many of these complexesexhibit photophysical behavior that can be readily controlled through a careful choice ofligands and/or substituents. With this perspective, we review the design and general syntheticmethods of some polypyridine ligands based on bipyridine, phenanthroline, terpyridine andquaterpyridine with/without anchoring groups with a view to correlate functionality ofligand structures with the observed photophysical, electroredox and power conversionefficiency of some examples of Ru(II polypyridyl complexes that have been reported andparticularly used in the DSSCs applications. The main interest, however, is focused onshowing the development of new polypyridine ligand materials containing long-rangeelectron transfer motifs such as the alkenyl, alkynyl and polyaromatic donor functionalities.

  12. Ionization of oriented carbonyl sulfide molecules by intense circularly polarized laser pulses

    DEFF Research Database (Denmark)

    Dimitrovski, Darko; Abu-Samha, Mahmoud; Madsen, Lars Bojer

    2011-01-01

    We present combined experimental and theoretical results on strong-field ionization of oriented carbonyl sulfide molecules by circularly polarized laser pulses. The obtained molecular frame photoelectron angular distributions show pronounced asymmetries perpendicular to the direction of the molec......We present combined experimental and theoretical results on strong-field ionization of oriented carbonyl sulfide molecules by circularly polarized laser pulses. The obtained molecular frame photoelectron angular distributions show pronounced asymmetries perpendicular to the direction......-dimensionally-oriented polar molecules, in particular asymmetries in the emission direction of the photoelectrons. In the following article [Phys. Rev. A 83, 023406 (2011)] the focus is to understand strong-field ionization from three-dimensionally-oriented asymmetric top molecules, in particular the suppression of electron...

  13. Molecular Active Sites in Heterogeneous Ir-La/C-Catalyzed Carbonylation of Methanol to Acetates.

    Science.gov (United States)

    Kwak, Ja Hun; Dagle, Robert; Tustin, Gerald C; Zoeller, Joseph R; Allard, Lawrence F; Wang, Yong

    2014-02-06

    We report that when Ir and La halides are deposited on carbon, exposure to CO spontaneously generates a discrete molecular heterobimetallic structure, containing an Ir-La covalent bond that acts as a highly active, selective, and stable heterogeneous catalyst for the carbonylation of methanol to produce acetic acid. This catalyst exhibits a very high productivity of ∼1.5 mol acetyl/mol Ir·s with >99% selectivity to acetyl (acetic acid and methyl acetate) without detectable loss in activity or selectivity for more than 1 month of continuous operation. The enhanced activity can be mechanistically rationalized by the presence of La within the ligand sphere of the discrete molecular Ir-La heterobimetallic structure, which acts as a Lewis acid to accelerate the normally rate-limiting CO insertion in Ir-catalyzed carbonylation. Similar approaches may provide opportunities for attaining molecular (single site) behavior similar to homogeneous catalysis on heterogeneous surfaces for other industrial applications.

  14. Influence of gamma radiation reaction on the hydroesterification of butenes catalyzed by metal carbonyls

    International Nuclear Information System (INIS)

    Velde, J. van der.

    1976-01-01

    In the hydro carboxylation reaction, which first has been studied by Reppe, olefine and acetylene compounds are processed with carbon monoxide and water at high pressures and high temperatures in the presence of metal carbonyls. This reaction can be enhanced considerably by application of ionizing radiation. Lower pressures and in particular lower temperatures can be used if gamma irradiation is performed during carboxylation. For the experiments a mixture of buten-1 and buten-2 as well as pure buten-1 and pure buten-2 has been used to study the behaviour of these olefines with respect to the isomerization of the reaction products and to the olefines not transformed in the reaction process. Replacing water, methanol has been used as a reaction component, thus obtaining directly the respective carbonyl acid esters, which can be analysed quantitatively and qualitatively with respect to their isomeric composition by gaschromatography. (orig./HK) [de

  15. Spectroscopic and theoretical studies on the aromaticity of pyrrol-2-yl-carbonyl conformers

    Science.gov (United States)

    Dubis, Alina T.; Wojtulewski, Sławomir; Filipkowski, Karol

    2013-06-01

    The aromaticity of s-cis and s-trans pyrrol-2-yl carbonyl conformers was studied by FT-IR, 1H NMR spectroscopy and DFT calculations at the B3LYP/6-311++G(d,p) level of theory. The Harmonic Oscillator Model of Aromaticity (HOMA) and Nucleus Independent Chemical Shift (NICS) indices were calculated to estimate π-electron delocalization in the pyrrole ring. The usefulness of infrared spectroscopy in the evaluation of the aromaticity of the homogeneous set of pyrroles is discussed. The influence of 2-substitution on different aspects of aromaticity and stability of the pyrrol-2-yl carbonyl conformers is also discussed. It is concluded that the substitution effect of the title pyrrole derivatives can be explained on the basis of theoretical and experimental measurements of π-electron delocalization, including IR data.

  16. Contribution to radiation-chemically catalyzed hydroformylation of butenes in the presence of metal carbonyls

    International Nuclear Information System (INIS)

    Joosten, L.

    1976-01-01

    In this paper a study is presented of the influence of gamma-radiation on the catalytic hydroformylation of olefines. As model olefines buten-1 and buten-2 as well as their mixtures have been used together with the catalysts di-cobalt octacarbonyle and rhodium (I) tristri phenyl-phosphine carbonyle hydride. In addition the catalytic activity of the VI. side group carbonyles Cr(CO) 6 , Mo(CO) 6 and W(CO) 6 has been studied under radiation chemical conditions. For this purpose a mixture of olefine, solvent (cyclo hexane) and calalyst has been pressurized and processed in a mixing autoklave together with a Co and H 2 (1:1) mixture, variing the reaction variables within certain limits. (orig.) [de

  17. Age-related carbonylation of fibrocartilage structural proteins drives tissue degenerative modification.

    Science.gov (United States)

    Scharf, Brian; Clement, Cristina C; Yodmuang, Supansa; Urbanska, Aleksandra M; Suadicani, Sylvia O; Aphkhazava, David; Thi, Mia M; Perino, Giorgio; Hardin, John A; Cobelli, Neil; Vunjak-Novakovic, Gordana; Santambrogio, Laura

    2013-07-25

    Aging-related oxidative stress has been linked to degenerative modifications in different organs and tissues. Using redox proteomic analysis and illustrative tandem mass spectrometry mapping, we demonstrate oxidative posttranslational modifications in structural proteins of intervertebral discs (IVDs) isolated from aging mice. Increased protein carbonylation was associated with protein fragmentation and aggregation. Complementing these findings, a significant loss of elasticity and increased stiffness was measured in fibrocartilage from aging mice. Studies using circular dichroism and intrinsic tryptophan fluorescence revealed a significant loss of secondary and tertiary structures of purified collagens following oxidation. Collagen unfolding and oxidation promoted both nonenzymatic and enzymatic degradation. Importantly, induction of oxidative modification in healthy fibrocartilage recapitulated the biochemical and biophysical modifications observed in the aging IVD. Together, these results suggest that protein carbonylation, glycation, and lipoxidation could be early events in promoting IVD degenerative changes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Design and fabrication of microfluidic mixer from carbonyl iron–PDMS composite membrane

    KAUST Repository

    Li, Jiaxing

    2010-10-12

    This paper introduces a carbonyl iron-PDMS (CI-PDMS) composite magnetic elastomer in which carbonyl iron (CI) particles are uniformly distributed in a PDMS matrix. The CI particles and the PDMS were mixed at different weight ratios and tested to determine the influence of CI concentration. The magnetic and mechanical properties of the magnetic elastomers were characterized, respectively, by vibrating-sample magnetometer and by tensile testing using a mechanical analyzer. The elastomer was found to exhibit high magnetization and good mechanical flexibility. The morphology and deformation of the CI-PDMS membrane also were observed. A magnetically actuated microfluidic mixer (that is, a micromixer) integrated with CI-PDMS elastomer membranes was successfully designed and fabricated. The high efficiency and quality of the mixing makes possible the impressive potential applications of this unique CI-PDMS material in microfluidic systems. © Springer-Verlag 2010.

  19. Alkylselenite-catalyzed Oxidative Carbonylation of Amines: Density Functional Theory Study

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Sun; Kim, Hoon Sik; Cheong, Minserk [Kyung Hee Univ., Seoul (Korea, Republic of)

    2012-11-15

    Ureas and carbamates have been conventionally produced by the reaction of amines with phosgene. However, phosgenation processes raise severe environmental concerns, which are attributed to the toxicity of phosgene and the formation of corrosive hydrogen chloride as a co-product. The considerable industrial interest in replacing current phosgene-based processes prompted several methods using non-phosgene routes including carbonylation of amines or nitro compounds and carbomethoxylation of amines with dialkylcarbonates. Among these, catalytic oxidative carbonylation of an amine in the presence of alcohol has been studied most extensively. Catalytic systems based on precious metals such as Rh and Pd are commonly used for this purpose, but most of these catalytic systems suffer from either low reactivity or severe reaction conditions such as high temperature and pressures. In conclusion, the facile change of selenium oxidation state by CO and O{sub 2} might be the main reason for the activity of the selenium catalyst for this reaction.

  20. Alkylselenite-catalyzed Oxidative Carbonylation of Amines: Density Functional Theory Study

    International Nuclear Information System (INIS)

    Hwang, Sun; Kim, Hoon Sik; Cheong, Minserk

    2012-01-01

    Ureas and carbamates have been conventionally produced by the reaction of amines with phosgene. However, phosgenation processes raise severe environmental concerns, which are attributed to the toxicity of phosgene and the formation of corrosive hydrogen chloride as a co-product. The considerable industrial interest in replacing current phosgene-based processes prompted several methods using non-phosgene routes including carbonylation of amines or nitro compounds and carbomethoxylation of amines with dialkylcarbonates. Among these, catalytic oxidative carbonylation of an amine in the presence of alcohol has been studied most extensively. Catalytic systems based on precious metals such as Rh and Pd are commonly used for this purpose, but most of these catalytic systems suffer from either low reactivity or severe reaction conditions such as high temperature and pressures. In conclusion, the facile change of selenium oxidation state by CO and O 2 might be the main reason for the activity of the selenium catalyst for this reaction

  1. Deoxygenative gem-difluoroolefination of carbonyl compounds with (chlorodifluoromethyltrimethylsilane and triphenylphosphine

    Directory of Open Access Journals (Sweden)

    Fei Wang

    2014-02-01

    Full Text Available Background: 1,1-Difluoroalkenes cannot only be used as valuable precursors for organic synthesis, but also act as bioisosteres for enzyme inhibitors. Among various methods for their preparation, the carbonyl olefination with difluoromethylene phosphonium ylide represents one of the most straightforward methods.Results: The combination of (chlorodifluoromethyltrimethylsilane (TMSCF2Cl and triphenylphosphine (PPh3 can be used for the synthesis of gem-difluoroolefins from carbonyl compounds. Comparative experiments demonstrate that TMSCF2Cl is superior to (bromodifluoromethyltrimethylsilane (TMSCF2Br and (trifluoromethyltrimethylsilane (TMSCF3 in this reaction.Conclusion: Similar to many other Wittig-type gem-difluoroolefination reactions in the presence of PPh3, the reaction of TMSCF2Cl with aldehydes and activated ketones is effective.

  2. Criegee Intermediates: What Direct Production and Detection Can Teach Us About Reactions of Carbonyl Oxides

    Science.gov (United States)

    Taatjes, Craig A.

    2017-05-01

    The carbonyl oxide intermediates in the ozonolysis of alkenes, often known as Criegee intermediates, are potentially important reactants in Earth's atmosphere. For decades, careful analysis of ozonolysis systems was employed to derive an understanding of the formation and reactions of these species. Recently it has proved possible to synthesize at least some of these intermediates separately from ozonolysis, and hence to measure their reaction kinetics directly. Direct measurements have allowed new or more detailed understanding of each type of gas-phase reaction that carbonyl oxides undergo, often acting as a complement to highly detailed ozonolysis experiments. Moreover, the use of direct characterization methods to validate increasingly accurate theoretical investigations can enhance their impact well beyond the set of specific reactions that have been measured. Reactions that initiate particles or fuel their growth could be a new frontier for direct measurements of Criegee intermediate chemistry.

  3. Analysis of protein carbonylation - pitfalls and promise in commonly used methods

    DEFF Research Database (Denmark)

    Rogowska-Wrzesinska, A.; Wojdyla, K.; Nedic, O.

    2014-01-01

    that research scientists are becoming more eager to be able to measure accurately the level of oxidized protein in biological materials, and to determine the precise site of the oxidative attack on the protein, in order to get insights into the molecular mechanisms involved in the progression of diseases....... Several methods for measuring protein carbonylation have been implemented in different laboratories around the world. However, to date no methods prevail as the most accurate, reliable, and robust. The present paper aims at giving an overview of the common methods used to determine protein carbonylation...... in biological material as well as to highlight the limitations and the potential. The ultimate goal is to give quick tips for a rapid decision making when a method has to be selected and taking into consideration the advantage and drawback of the methods....

  4. Analysis of protein carbonylation-pitfalls and promise in commonly used methods

    DEFF Research Database (Denmark)

    Rogowska-Wrzesinska, Adelina; Wojdyla, K; Nedić, O

    2014-01-01

    that research scientists are becoming more eager to be able to measure accurately the level of oxidized protein in biological materials, and to determine the precise site of the oxidative attack on the protein, in order to get insights into the molecular mechanisms involved in the progression of diseases....... Several methods for measuring protein carbonylation have been implemented in different laboratories around the world. However, to date no methods prevail as the most accurate, reliable, and robust. The present paper aims at giving an overview of the common methods used to determine protein carbonylation...... in biological material as well as to highlight the limitations and the potential. The ultimate goal is to give quick tips for a rapid decision making when a method has to be selected and taking into consideration the advantage and drawback of the methods....

  5. Novel Routes to Ethylene Glycol Synthesis via Acid-Catalyzed Carbonylation of Formaldehyde and Dimethoxymethane

    OpenAIRE

    Celik, Fuat Emin

    2010-01-01

    Carbon-carbon bond forming carbonylation reactions were investigated as candidates to replace ethene epoxidation as the major source of ethylene glycol production. This work was motivated by the potentially lower cost of carbon derived from synthesis gas as compared to ethylene. Synthesis gas can be produced from relatively abundant and cheap natural gas, coal, and biomass resources whereas ethylene is derived from increasingly scarce and expensive crude oil. From synthesis gas, a range of...

  6. Carbonylative Heck Reactions Using CO Generated ex Situ in a Two-Chamber System

    DEFF Research Database (Denmark)

    Hermange, Philippe; Gøgsig, Thomas; Lindhardt, Anders Thyboe

    2011-01-01

    A carbonylative Heck reaction of aryl iodides and styrene derivatives employing a two-chamber system using a stable, crystalline, and nontransition metal based carbon monoxide source is reported. By applying near-stoichiometric amounts of the carbon monoxide precursor, an effective exploitation o...... of the hazardous CO gas is obtained affording chalcone derivatives in good yields. Application to isotope labeling, incorporating 13CO, was further established....

  7. Organocatalyzed Asymmetric α-Oxidation, α-Aminoxylation and α-Amination of Carbonyl Compounds

    OpenAIRE

    Worawan Bhanthumnavin; Tirayut Vilaivan

    2010-01-01

    Organocatalytic asymmetric α-oxidation and amination reactions of carbonyl compounds are highly useful synthetic methodologies, especially in generating chiral building blocks that previously have not been easily accessible by traditional methods. The concept is relatively new and therefore the list of new catalysts, oxidizing and aminating reagents, as well as new substrates, are expanding at an amazing rate. The scope of this review includes new reactions and catalysts, mechanistic aspects ...

  8. The interaction of metal carbonyl compounds with organic polymers and monomers

    OpenAIRE

    Lyons, Michael P.

    1993-01-01

    The photochemistry of W(CO)6, Mo(CO)6, and Cr(CO)6 in the presence of monomeric and polymeric triphenylphosphine ligands was investigated in toluene solution, using laser flash photolysis with 355nm excitation. The mechanism and kinetics of interaction of the primary photoproducts M(CO)5(toluene) (M = W, Mo, or Cr) with the various monomeric ligands were investigated. Interaction of the metal carbonyl photofragments with various homopolymers is also discussed. The polymerisation methods used ...

  9. Plasma-treated carbonyl iron particles as a dispersed phase in magnetorheological fluids

    Czech Academy of Sciences Publication Activity Database

    Sedlačík, M.; Pavlínek, V.; Lehocký, M.; Mráček, A.; Grulich, O.; Švrčinová, Petra; Filip, Petr; Vesel, A.

    2011-01-01

    Roč. 387, 1-3 (2011), s. 99-103 ISSN 0927-7757 Grant - others:GA ČR(CZ) GD104/09/H080; OP VaVpI(XE) CZ.1.05/2.1.00/03.0111 Program:GD Institutional research plan: CEZ:AV0Z20600510 Keywords : carbonyl iron * magnetorheological fluid * plasma * viscoelasticity Subject RIV: BK - Fluid Dynamics Impact factor: 2.236, year: 2011

  10. Expression, purification, crystallization and preliminary X-ray diffraction analysis of carbonyl reductase from Candida parapsilosis ATCC 7330

    International Nuclear Information System (INIS)

    Aggarwal, Nidhi; Mandal, P. K.; Gautham, Namasivayam; Chadha, Anju

    2013-01-01

    The expression, purification, crystallization, preliminary X-ray diffraction and molecular-replacement studies on C. parapsilosis carbonyl reductase are reported. The NAD(P)H-dependent carbonyl reductase from Candida parapsilosis ATCC 7330 catalyses the asymmetric reduction of ethyl 4-phenyl-2-oxobutanoate to ethyl (R)-4-phenyl-2-hydroxybutanoate, a precursor of angiotensin-converting enzyme inhibitors such as Cilazapril and Benazepril. The carbonyl reductase was expressed in Escherichia coli and purified by GST-affinity and size-exclusion chromatography. Crystals were obtained by the hanging-drop vapour-diffusion method and diffracted to 1.86 Å resolution. The asymmetric unit contained two molecules of carbonyl reductase, with a solvent content of 48%. The structure was solved by molecular replacement using cinnamyl alcohol dehydrogenase from Saccharomyces cerevisiae as a search model

  11. Selectivity of a heterogeneous rhodium catalyst for the carbonylation of monohydric alcohols

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, B; Scurrell, M S

    1977-01-01

    Selectivity of a heterogeneous rhodium catalyst for the carbonylation of monohydric alcohols with carbon monoxide in the presence of the corresponding alkyl iodides as promotors was studied in a glass reactor at approx. 0.05:1 alcohol/carbon monoxide ratio. The 1% by wt rhodium-zeolite catalyst was prepared by immersing a Linde molecular sieve zeolite Type 13X in rhodium trichloride at 80/sup 0/C for 15 hr. Methanol was converted to methyl acetate at 433/sup 0/-513/sup 0/K with selectivites > 90% even at the highest temperatures, and dimethyl ether was by-produced. In the absence of methyl iodide, the carbonylation rate decreased drastically but the dehydration was virtually unaffected. The selectivity for ethanol carbonylation decreased from 99% at 383/sup 0/K to 6% at 523/sup 0/K due to the formation of ethylene (predominant at > 470/sup 0/K) and diethyl ether. The only product of the reaction with propan-2-ol studied at 433/sup 0/ or 473/sup 0/K was propene with 100% conversion at 473/sup 0/K. These results are consistent with the relative ease of reactant dehydration on polar catalysts. Table and 13 references.

  12. Gas chromatographic analysis of reactive carbonyl compounds formed from lipids upon UV-irradiation

    International Nuclear Information System (INIS)

    Dennis, K.J.; Shibamoto, T.

    1990-01-01

    Peroxidation of lipids produces carbonyl compounds; some of these, e.g., malonaldehyde and 4-hydroxynonenal, are genotoxic because of their reactivity with biological nucleophiles. Analysis of the reactive carbonyl compounds is often difficult. The methylhydrazine method developed for malonaldehyde analysis was applied to simultaneously measure the products formed from linoleic acid, linolenic acid, arachidonic acid, and squalene upon ultraviolet-irradiation (UV-irradiation). The photoreaction products, saturated monocarbonyl, alpha,beta-unsaturated carbonyls, and beta-dicarbonyls, were derivatized with methylhydrazine to give hydrazones, pyrazolines, and pyrazoles, respectively. The derivatives were analyzed by gas chromatography and gas chromatography-mass spectrometry. Lipid peroxidation products identified included formaldehyde, acetaldehyde, acrolein, malonaldehyde, n-hexanal, and 4-hydroxy-2-nonenal. Malonaldehyde levels formed upon 4 hr of irradiation were 0.06 micrograms/mg from squalene, 2.4 micrograms/mg from linolenic acid, and 5.7 micrograms/mg from arachidonic acid. Significant levels of acrolein (2.5 micrograms/mg) and 4-hydroxy-2-nonenal (0.17 micrograms/mg) were also produced from arachidonic acid upon 4 hr irradiation

  13. A carnosine intervention study in overweight human volunteers: bioavailability and reactive carbonyl species sequestering effect

    Science.gov (United States)

    Regazzoni, Luca; de Courten, Barbora; Garzon, Davide; Altomare, Alessandra; Marinello, Cristina; Jakubova, Michaela; Vallova, Silvia; Krumpolec, Patrik; Carini, Marina; Ukropec, Jozef; Ukropcova, Barbara; Aldini, Giancarlo

    2016-06-01

    Carnosine is a natural dipeptide able to react with reactive carbonyl species, which have been recently associated with the onset and progression of several human diseases. Herein, we report an intervention study in overweight individuals. Carnosine (2 g/day) was orally administered for twelve weeks in order to evaluate its bioavailability and metabolic fate. Two carnosine adducts were detected in the urine samples of all subjects. Such adducts are generated from a reaction with acrolein, which is one of the most toxic and reactive compounds among reactive carbonyl species. However, neither carnosine nor adducts have been detected in plasma. Urinary excretion of adducts and carnosine showed a positive correlation although a high variability of individual response to carnosine supplementation was observed. Interestingly, treated subjects showed a significant decrease in the percentage of excreted adducts in reduced form, accompanied by a significant increase of the urinary excretion of both carnosine and carnosine-acrolein adducts. Altogether, data suggest that acrolein is entrapped in vivo by carnosine although the response to its supplementation is possibly influenced by individual diversities in terms of carnosine dietary intake, metabolism and basal production of reactive carbonyl species.

  14. Nitrite promotes protein carbonylation and Strecker aldehyde formation in experimental fermented sausages: are both events connected?

    Science.gov (United States)

    Villaverde, A; Ventanas, J; Estévez, M

    2014-12-01

    The role played by curing agents (nitrite, ascorbate) on protein oxidation and Strecker aldehyde formation is studied. To fulfill this objective, increasing concentrations of nitrite (0, 75 and 150ppm) and ascorbate (0, 250 and 500ppm) were added to sausages subjected to a 54day drying process. The concurrence of intense proteolysis, protein carbonylation and formation of Strecker aldehydes during processing of sausages suggests that α-aminoadipic semialdehyde (AAS) and γ-glutamic semialdehyde (GGS) may be implicated in the formation of Strecker aldehydes. The fact that nitrite (150ppm, ingoing amount) significantly promoted the formation of protein carbonyls at early stages of processing and the subsequent formation of Strecker aldehydes provides strength to this hypothesis. Ascorbate (125 and 250ppm) controlled the overall extent of protein carbonylation in sausages without declining the formation of Strecker aldehydes. These results may contribute to understanding the chemistry fundamentals of the positive influence of nitrite on the flavor and overall acceptability of cured muscle foods. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Seasonal behavior of carbonyls and source characterization of formaldehyde (HCHO) in ambient air

    Science.gov (United States)

    Lui, K. H.; Ho, Steven Sai Hang; Louie, Peter K. K.; Chan, C. S.; Lee, S. C.; Hu, Di; Chan, P. W.; Lee, Jeffrey Chi Wai; Ho, K. F.

    2017-03-01

    Gas-phase formaldehyde (HCHO) is an intermediate and a sensitive indicator for volatile organic compounds (VOCs) oxidation, which drives tropospheric ozone production. Effective photochemical pollution control strategies demand a thorough understanding of photochemical oxidation precursors, making differentiation between sources of primary and secondary generated HCHO inevitable. Spatial and seasonal variations of airborne carbonyls based on two years of measurements (2012-2013), coupled with a correlation-based HCHO source apportionment analysis, were determined for three sampling locations in Hong Kong (denoted HT, TC, and YL). Formaldehyde and acetaldehyde were the two most abundant compounds of the total quantified carbonyls. Pearson's correlation analysis (r > 0.7) implies that formaldehyde and acetaldehyde possibly share similar sources. The total carbonyl concentration trends (HT rural). A regression analysis further quantifies the relative primary HCHO source contributions at HT (∼13%), TC (∼21%), and YL (∼40%), showing more direct vehicular emissions in urban than rural areas. Relative secondary source contributions at YL (∼36%) and TC (∼31%) resemble each other, implying similar urban source contributions. Relative background source contributions at TC could be due to a closed structure microenvironment that favors the trapping of HCHO. Comparable seasonal differences are observed at all stations. The results of this study will aid in the development of a new regional ozone (O3) control policy, as ambient HCHO can enhance O3 production and also be produced from atmospheric VOCs oxidation (secondary HCHO).

  16. Role of Protein Carbonylation in Skeletal Muscle Mass Loss Associated with Chronic Conditions

    Directory of Open Access Journals (Sweden)

    Esther Barreiro

    2016-05-01

    Full Text Available Muscle dysfunction, characterized by a reductive remodeling of muscle fibers, is a common systemic manifestation in highly prevalent conditions such as chronic heart failure (CHF, chronic obstructive pulmonary disease (COPD, cancer cachexia, and critically ill patients. Skeletal muscle dysfunction and impaired muscle mass may predict morbidity and mortality in patients with chronic diseases, regardless of the underlying condition. High levels of oxidants may alter function and structure of key cellular molecules such as proteins, DNA, and lipids, leading to cellular injury and death. Protein oxidation including protein carbonylation was demonstrated to modify enzyme activity and DNA binding of transcription factors, while also rendering proteins more prone to proteolytic degradation. Given the relevance of protein oxidation in the pathophysiology of many chronic conditions and their comorbidities, the current review focuses on the analysis of different studies in which the biological and clinical significance of the modifications induced by reactive carbonyls on proteins have been explored so far in skeletal muscles of patients and animal models of chronic conditions such as COPD, disuse muscle atrophy, cancer cachexia, sepsis, and physiological aging. Future research will elucidate the specific impact and sites of reactive carbonyls on muscle protein content and function in human conditions.

  17. Carbonyl compounds and PAH emissions from CNG heavy-duty engine

    International Nuclear Information System (INIS)

    Gambino, M.; Cericola, R.; Corbo, P.; Iannaccone, S.

    1993-01-01

    Previous works carried out in Istituto Motori laboratories have shown that natural gas is a suitable fuel for general means of transportation. This is because of its favorable effects on engine performance and pollutant emissions. The natural gas fueled engine provided the same performance as the diesel engine, met R49 emission standards, and showed very low smoke levels. On the other hand, it is well known that internal combustion engines emit some components that are harmful for human health, such as carbonyl compounds and polycyclic aromatic hydrocarbons (PAH). This paper shows the results of carbonyl compounds and PAH emissions analysis for a heavy-duty Otto cycle engine fueled with natural gas. The engine was tested using the R49 cycle that is used to measure the regulated emissions. The test analysis has been compared with an analysis of a diesel engine, tested under the same conditions. Total PAH emissions from the CNG engine were about three orders of magnitude lower than from the diesel engine. Formaldehyde emission from the CNG engine was about ten times as much as from the diesel engine, while emissions of other carbonyl compounds were comparable

  18. Effect of fiber material on ozone removal and carbonyl production from carpets

    Science.gov (United States)

    Abbass, Omed A.; Sailor, David J.; Gall, Elliott T.

    2017-01-01

    Indoor air quality is affected by indoor materials such as carpets that may act as sources and/or sinks of gas-phase air pollutants. Heterogeneous reactions of ozone with carpets may result in potentially harmful products. In this study, indoor residential carpets of varying fiber types were tested to evaluate their ability to remove ozone, and to assess their role in the production of carbonyls when exposed to elevated levels of ozone. Tests were conducted with six types of new unused carpets. Two sets of experiments were conducted, the first measured ozone removal and ozone deposition velocities, and the second measured primary carbonyl production and secondary production as a result of exposure to ozone. The tests were conducted using glass chambers with volume of 52 L each. Air exchange rates for all tests were 3 h-1. The ozone removal tests show that, for the conditions tested, the polyester carpet sample had the lowest ozone removal (40%), while wool carpet had the greatest ozone removal (65%). Most carpet samples showed higher secondary than primary carbonyl emissions, with carpets containing polypropylene fibers being a notable exception. Carpets with polyester fibers had both the highest primary and secondary emissions of formaldehyde among all samples tested. While it is difficult to make blanket conclusions about the relative air quality merits of various carpet fiber options, it is clear that ozone removal percentages and emissions of volatile organic compounds can vary drastically as a function of fiber type.

  19. Excited state characterization of carbonyl containing carotenoids: a comparison between single and multireference descriptions

    Science.gov (United States)

    Spezia, Riccardo; Knecht, Stefan; Mennucci, Benedetta

    Carotenoids can play multiple roles in biological photoreceptors thanks to their rich photophysics. In the present work, we have investigated six of the most common carbonyl containing carotenoids: Echinenone, Canthaxanthin, Astaxanthin, Fucoxanthin, Capsanthin and Capsorubin. Their excitation properties are investigated by means of a hybrid density functional theory (DFT) and multireference configuration interaction (MRCI) approach to elucidate the role of the carbonyl group: the bright transition is of {\\pi}{\\pi}* character, as expected, but the presence of a C=O moiety reduces the energy of n{\\pi}* transitions which may become closer to the {\\pi}{\\pi}* transition, in particular as the conjugation chain decreases. This can be related to the presence of a low-lying charge transfer state typical of short carbonyl- containing carotenoids. The DFT/MRCI results are finally used to benchmark single- reference time-dependent DFT-based methods: among the investigated functionals, the meta- GGA (and in particular M11L and MN12L) functionals show to perform the best for all six investigated systems.

  20. Antibacterial and DNA cleavage activity of carbonyl functionalized N-heterocyclic carbene-silver(I) and selenium compounds

    Science.gov (United States)

    Haque, Rosenani A.; Iqbal, Muhammad Adnan; Mohamad, Faisal; Razali, Mohd R.

    2018-03-01

    The article describes syntheses and characterizations of carbonyl functionalized benzimidazolium salts, I-IV. While salts I-III are unstable at room temperature, salt IV remained stable and was further utilised to form N-heterocyclic carbene (NHC) compounds of silver(I), V and VI, and selenium compound, VII respectively. Compounds IV-VII were tested for their antibacterial potential against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Salt IV shows a very low inhibition potential (minimum inhibitory concentration, MIC 500 μg/mL) compared to the respective silver(I)-NHC, V and VI (MIC 31.25 μg/mL against both, E. coli and S. aureus) and selenium compound, VII (MIC 125 μg/mL against E. coli and 62.50 μg/mL against S. aureus). In DNA cleavage abilities, all the test compounds cleave DNA in which the VII cleaves the DNA at the faster rate. Meanwhile, the silver(I)-NHC complexes V and VI act at the same mode and pattern of DNA cleavage while VII is similar to IV.

  1. Microwave absorption properties of a wave-absorbing coating employing carbonyl-iron powder and carbon black

    International Nuclear Information System (INIS)

    Liu Lidong; Duan Yuping; Ma Lixin; Liu Shunhua; Yu Zhen

    2010-01-01

    To prevent serious electromagnetic interference, a single-layer wave-absorbing coating employing complex absorbents composed of carbonyl-iron powder (CIP) and carbon black (CB) with epoxy resin as matrix was prepared. The morphologies of CIP and CB were characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM), respectively. The electromagnetic parameters of CIP and CB were measured in the frequency range of 2-18 GHz by transmission/reflection technology, and the electromagnetic loss mechanisms of the two particles were discussed, respectively. The microwave absorption properties of the coatings were investigated by measuring reflection loss (RL) using arch method. The effects of CIP ratio, CB content and thickness on the microwave absorption properties were discussed, respectively. The results showed that the higher thickness, CIP or CB content could make the absorption band shift towards the lower frequency range. Significantly, the wave-absorbing coating could be applied in different frequency ranges according to actual demand by controlling the content of CIP or CB in composites.

  2. Microwave absorption properties of a wave-absorbing coating employing carbonyl-iron powder and carbon black

    Science.gov (United States)

    Liu, Lidong; Duan, Yuping; Ma, Lixin; Liu, Shunhua; Yu, Zhen

    2010-11-01

    To prevent serious electromagnetic interference, a single-layer wave-absorbing coating employing complex absorbents composed of carbonyl-iron powder (CIP) and carbon black (CB) with epoxy resin as matrix was prepared. The morphologies of CIP and CB were characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM), respectively. The electromagnetic parameters of CIP and CB were measured in the frequency range of 2-18 GHz by transmission/reflection technology, and the electromagnetic loss mechanisms of the two particles were discussed, respectively. The microwave absorption properties of the coatings were investigated by measuring reflection loss (RL) using arch method. The effects of CIP ratio, CB content and thickness on the microwave absorption properties were discussed, respectively. The results showed that the higher thickness, CIP or CB content could make the absorption band shift towards the lower frequency range. Significantly, the wave-absorbing coating could be applied in different frequency ranges according to actual demand by controlling the content of CIP or CB in composites.

  3. Dormancy alleviation by NO or HCN leading to decline of protein carbonylation levels in apple (Malus domestica Borkh.) embryos.

    Science.gov (United States)

    Krasuska, Urszula; Ciacka, Katarzyna; Dębska, Karolina; Bogatek, Renata; Gniazdowska, Agnieszka

    2014-08-15

    Deep dormancy of apple (Malus domestica Borkh.) embryos can be overcome by short-term pre-treatment with nitric oxide (NO) or hydrogen cyanide (HCN). Dormancy alleviation of embryos modulated by NO or HCN and the first step of germination depend on temporary increased production of reactive oxygen species (ROS). Direct oxidative attack on some amino acid residues or secondary reactions via reactive carbohydrates and lipids can lead to the formation of protein carbonyl derivatives. Protein carbonylation is a widely accepted covalent and irreversible modification resulting in inhibition or alteration of enzyme/protein activities. It also increases the susceptibility of proteins to proteolytic degradation. The aim of this work was to investigate protein carbonylation in germinating apple embryos, the dormancy of which was removed by pre-treatment with NO or HCN donors. It was performed using a quantitative spectrophotometric method, while patterns of carbonylated protein in embryo axes were analyzed by immunochemical techniques. The highest concentration of protein carbonyl groups was observed in dormant embryos. It declined in germinating embryos pre-treated with NO or HCN, suggesting elevated degradation of modified proteins during seedling formation. A decrease in the concentration of carbonylated proteins was accompanied by modification in proteolytic activity in germinating apple embryos. A strict correlation between the level of protein carbonyl groups and cotyledon growth and greening was detected. Moreover, direct in vitro carbonylation of BSA treated with NO or HCN donors was analyzed, showing action of both signaling molecules as protein oxidation agents. Copyright © 2014 Elsevier GmbH. All rights reserved.

  4. Spatial distributions of and diurnal variations in low molecular weight carbonyl compounds in coastal seawater, and the controlling factors

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Kazuhiko, E-mail: takedaq@hiroshima-u.ac.jp [Graduate School of Biosphere Science, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521 (Japan); Katoh, Shinya; Mitsui, Yumi; Nakano, Shinichi [Graduate School of Biosphere Science, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521 (Japan); Nakatani, Nobutake [Graduate School of Biosphere Science, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521 (Japan); Department of Environmental and Symbiotic Sciences, Rakuno Gakuen University, 582 Bunkyodai-Midorimachi, Ebetsu, Hokkaido 069-8501 (Japan); Sakugawa, Hiroshi [Graduate School of Biosphere Science, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521 (Japan)

    2014-09-15

    We studied the spatial distributions of and the diurnal variations in four low molecular weight (LMW) carbonyl compounds, formaldehyde, acetaldehyde, propionaldehyde, and glyoxal, in coastal seawater. The samples were taken from the coastal areas of Hiroshima Bay, the Iyo Nada, and the Bungo Channel, western Japan. The formaldehyde, acetaldehyde, and glyoxal concentrations were higher in the northern part of Hiroshima Bay than at offshore sampling points in the Iyo Nada and the Bungo Channel. These three compounds were found at much higher concentrations in the surface water than in deeper water layers in Hiroshima Bay. It is noteworthy that propionaldehyde was not detected in any of the seawater samples, the concentrations present being lower than the detection limit (1 nanomole per liter (nM)) of the high performance liquid chromatography (HPLC) system we used. Photochemical and biological experiments were performed in the laboratory to help understand the characteristic distributions and fates of the LMW carbonyl compounds. The primary process controlling their fate in the coastal environment appears to be their biological consumption. The direct photo degradation of propionaldehyde, initiated by ultraviolet (UV) absorption, was observed, although formaldehyde and acetaldehyde were not degraded by UV irradiation. Our results suggest that the degradation of the LMW carbonyl compounds by photochemically formed hydroxyl radicals is relatively insignificant in the study area. Atmospheric deposition is a possible source of soluble carbonyl compounds in coastal surface seawater, but it may not influence the carbonyl concentrations in offshore waters. - Highlights: • Low molecular weight (LMW) carbonyl compounds in coastal seawater were determined. • Photochemical productions of LMW carbonyl compounds in seawater were observed. • LMW carbonyl compounds were largely consumed biologically. • Photochemical degradation was relatively insignificant in the study area.

  5. Spatial distributions of and diurnal variations in low molecular weight carbonyl compounds in coastal seawater, and the controlling factors

    International Nuclear Information System (INIS)

    Takeda, Kazuhiko; Katoh, Shinya; Mitsui, Yumi; Nakano, Shinichi; Nakatani, Nobutake; Sakugawa, Hiroshi

    2014-01-01

    We studied the spatial distributions of and the diurnal variations in four low molecular weight (LMW) carbonyl compounds, formaldehyde, acetaldehyde, propionaldehyde, and glyoxal, in coastal seawater. The samples were taken from the coastal areas of Hiroshima Bay, the Iyo Nada, and the Bungo Channel, western Japan. The formaldehyde, acetaldehyde, and glyoxal concentrations were higher in the northern part of Hiroshima Bay than at offshore sampling points in the Iyo Nada and the Bungo Channel. These three compounds were found at much higher concentrations in the surface water than in deeper water layers in Hiroshima Bay. It is noteworthy that propionaldehyde was not detected in any of the seawater samples, the concentrations present being lower than the detection limit (1 nanomole per liter (nM)) of the high performance liquid chromatography (HPLC) system we used. Photochemical and biological experiments were performed in the laboratory to help understand the characteristic distributions and fates of the LMW carbonyl compounds. The primary process controlling their fate in the coastal environment appears to be their biological consumption. The direct photo degradation of propionaldehyde, initiated by ultraviolet (UV) absorption, was observed, although formaldehyde and acetaldehyde were not degraded by UV irradiation. Our results suggest that the degradation of the LMW carbonyl compounds by photochemically formed hydroxyl radicals is relatively insignificant in the study area. Atmospheric deposition is a possible source of soluble carbonyl compounds in coastal surface seawater, but it may not influence the carbonyl concentrations in offshore waters. - Highlights: • Low molecular weight (LMW) carbonyl compounds in coastal seawater were determined. • Photochemical productions of LMW carbonyl compounds in seawater were observed. • LMW carbonyl compounds were largely consumed biologically. • Photochemical degradation was relatively insignificant in the study area

  6. Time and dose effects of cigarette smoke and acrolein on protein carbonyl formation in HaCaT keratinocytes.

    Science.gov (United States)

    Avezov, K; Reznick, A Z; Aizenbud, D

    2015-01-01

    Cigarette smoke (CS) is an important environmental source of human exposure to a highly toxic and chemically active α,β-unsaturated aldehyde: acrolein. It is capable of causing protein carbonylation and dysfunction, especially in oral tissues of smokers, constantly exposed to CS toxic constituents. The foremost damage is considered to be cumulative, but even a short exposure can be potentially harmful. The objectives of the current study were to examine the short time and dose effects of direct CS and acrolein exposure on intracellular protein carbonylation in epithelial cells. HaCaT-keratinocytes were exposed to different doses of acrolein and whole phase CS using a unique smoking simulator apparatus that mimics the exposure in smokers. The rate of intracellular protein carbonyl modification was examined 10-60 min after the exposure by Western blot. In addition, the effect of pre-incubation with a thiol scavenger N-acetylcysteine (NAC) was also assessed. We found that intracellular protein carbonyls increased as fast as 10 min after CS exposure and their concentration doubled after 20 min, with a slight elevation afterwards. Also, carbonyl levels increased gradually as CS and acrolein doses were elevated. Addition of 1 mM NAC neutralized part of the damage. We conclude that CS and acrolein intracellular protein carbonylation is dose- and time- dependent. Even a short time exposure to CS and its aldehydic constituents can be potentially harmful.

  7. Density Functional Studies on the Complexation and Spectroscopy of Uranyl Ligated with Acetonitrile and Acetone Derivatives

    International Nuclear Information System (INIS)

    Schoendorff, George E.; Windus, Theresa L.; De Jong, Wibe A.

    2009-01-01

    The coordination of nitrile (acetonitrile, propionitrile, and benzonitrile) and carbonyl (formaldehyde, ethanal, and acetone) ligands to the uranyl dication (UO22+) has been examined using density functional theory (DFT) utilizing relativistic effective core potentials (RECPs). Complexes containing up to six ligands have been modeled for all ligands except formaldehyde, for which no minimum could be found. A comparison of relative binding energies indicates that five coordinate complexes are predominant while a six coordinate complex involving propionitrile ligands might be possible. Additionally, the relative binding energy and the weakening of the uranyl bond is related to the size of the ligand and, in general, nitriles bind more strongly to uranyl than carbonyls.

  8. Computational Elucidation of a Role That Brønsted Acidification of the Lewis Acid-Bound Water Might Play in the Hydrogenation of Carbonyl Compounds with H2 in Lewis Basic Solvents.

    Science.gov (United States)

    Heshmat, Mojgan; Privalov, Timofei

    2017-08-25

    Brønsted acidification of water by Lewis acid (LA) complexation is one of the fundamental principles in chemistry. Using transition-state calculations (TS), herein we investigate the role that Brønsted acidification of the LA-bound water might play in the mechanism of the hydrogenation of carbonyl compounds in Lewis basic solvents under non-anhydrous conditions. The potential energy scans and TS calculations were carried out with a series of eight borane LAs as well as the commonly known strong LA AlCl 3 in 1,4-dioxane or THF as Lewis basic solvents. Our molecular model consists of the dative LA-water adduct with hydrogen bonds to acetone and a solvent molecule plus one additional solvent molecule that participates is the TS structure describing the cleavage of H 2 at acetone's carbonyl carbon atom. In all the molecular models applied here, acetone (O=CMe 2 ) is the archetypical carbonyl substrate. We demonstrate that Brønsted acidification of the LA-bound water can indeed lower the barrier height of the solvent-involving H 2 -cleavage at the acetone's carbonyl carbon atom. This is significant because at present it is believed that the mechanism of the herein considered reaction is described by the same mechanism regardless of whether the reaction conditions are strictly anhydrous or non-anhydrous. Our results offer an alternative to this belief that warrants consideration and further study. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. The use of biodiesel blends on a non-road generator and its impacts on ozone formation potentials based on carbonyl emissions

    International Nuclear Information System (INIS)

    Chai, Ming; Lu, Mingming; Liang, Fuyan; Tzillah, Aisha; Dendramis, Nancy; Watson, Libya

    2013-01-01

    In this study, emissions of carbonyl compounds from the use B50 and B100 were measured with a non-road diesel generator. A total of 25 carbonyl compounds were identified in the exhaust, including 10 with laboratory-synthesized standards. Formaldehyde, acetaldehyde, and acrolein were found as the most abundant carbonyl compounds emitted for both diesel and biodiesel. The sulphur content of diesel fuels and the source of biodiesel fuels were not found to have a significant impact on the emission of carbonyl compounds. The overall maximum incremental reactivity (MIR) was the highest at 0 kW and slightly increased from 25 to 75 kW. The MIR of B100 was the highest, followed by diesel and B50, which is consistent with the emission rates of total carbonyl compounds. This suggests that the use of biodiesel blends may be more beneficial to the environment than using pure biodiesel. -- Highlights: •Carbonyl compound emission from biodiesel blends combustion on a non-road generator. •25 compounds were identified, including 10 by laboratory-synthesized standards. •Sources of biodiesel have insignificant impacts on carbonyl compounds emission. •Sulphur contents have insignificant impacts on carbonyl compounds emission. •MIR of emitted carbonyls decreases in the following order: B100, diesel, B50. -- The study found that B50 resulted in lower total carbonyl emission rates and ozone formation potential resultant from these compounds, whereas both increased with B100

  10. Protein conjugated with aldehydes derived from lipid peroxidation as an independent parameter of the carbonyl stress in the kidney damage

    Directory of Open Access Journals (Sweden)

    Medina-Navarro Rafael

    2011-11-01

    Full Text Available Abstract Background One of the well-defined and characterized protein modifications usually produced by oxidation is carbonylation, an irreversible non-enzymatic modification of proteins. However, carbonyl groups can be introduced into proteins by non-oxidative mechanisms. Reactive carbonyl compounds have been observed to have increased in patients with renal failure. In the present work we have described a procedure designed as aldehyde capture to calculate the protein carbonyl stress derived solely from lipid peroxidation. Methods Acrolein-albumin adduct was prepared as standard at alkaline pH. Rat liver microsomal membranes and serum samples from patients with diabetic nephropathy were subjected to the aldehyde capture procedure and aldol-protein formation. Before alkalinization and incubation, samples were precipitated and redisolved in 6M guanidine. The absorbances of the samples were read with a spectrophotometer at 266 nm against a blank of guanidine. Results Evidence showed abundance of unsaturated aldehydes derived from lipid peroxidation in rat liver microsomal membranes and in the serum of diabetic patients with advanced chronic kidney disease. Carbonyl protein and aldol-proteins resulted higher in the diabetic nephropathy patients (p Conclusion The aldehyde-protein adduct represents a non oxidative component of carbonyl stress, independent of the direct amino acid oxidation and could constitute a practical and novelty strategy to measure the carbonyl stress derived solely from lipid peroxidation and particularly in diabetic nephropathy patients. In addition, we are in a position to propose an alternative explanation of why alkalinization of urine attenuates rhabdomyolysis-induced renal dysfunction.

  11. Characterisation and optimisation of a method for the detection and quantification of atmospherically relevant carbonyl compounds in aqueous medium

    Science.gov (United States)

    Rodigast, M.; Mutzel, A.; Iinuma, Y.; Haferkorn, S.; Herrmann, H.

    2015-01-01

    Carbonyl compounds are ubiquitous in the atmosphere and either emitted primarily from anthropogenic and biogenic sources or they are produced secondarily from the oxidation of volatile organic compounds (VOC). Despite a number of studies about the quantification of carbonyl compounds a comprehensive description of optimised methods is scarce for the quantification of atmospherically relevant carbonyl compounds. Thus a method was systematically characterised and improved to quantify carbonyl compounds. Quantification with the present method can be carried out for each carbonyl compound sampled in the aqueous phase regardless of their source. The method optimisation was conducted for seven atmospherically relevant carbonyl compounds including acrolein, benzaldehyde, glyoxal, methyl glyoxal, methacrolein, methyl vinyl ketone and 2,3-butanedione. O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) was used as derivatisation reagent and the formed oximes were detected by gas chromatography/mass spectrometry (GC/MS). The main advantage of the improved method presented in this study is the low detection limit in the range of 0.01 and 0.17 μmol L-1 depending on carbonyl compounds. Furthermore best results were found for extraction with dichloromethane for 30 min followed by derivatisation with PFBHA for 24 h with 0.43 mg mL-1 PFBHA at a pH value of 3. The optimised method was evaluated in the present study by the OH radical initiated oxidation of 3-methylbutanone in the aqueous phase. Methyl glyoxal and 2,3-butanedione were found to be oxidation products in the samples with a yield of 2% for methyl glyoxal and 14% for 2,3-butanedione.

  12. Cross-talk between lipid and protein carbonylation in a dynamic cardiomyocyte model of mild nitroxidative stress

    Directory of Open Access Journals (Sweden)

    Eva Griesser

    2017-04-01

    Full Text Available Reactive oxygen and nitrogen species (ROS/RNS play an important role in the regulation of cardiac function. Increase in ROS/RNS concentration results in lipid and protein oxidation and is often associated with onset and/or progression of many cardiovascular disorders. However, interplay between lipid and protein modifications has not been simultaneously studied in detail so far. Biomolecule carbonylation is one of the most common biomarkers of oxidative stress. Using a dynamic model of nitroxidative stress we demonstrated rapid changes in biomolecule carbonylation in rat cardiomyocytes. Levels of carbonylated species increased as early as 15 min upon treatment with the peroxynitrite donor, 3-morpholinosydnonimine (SIN-1, and decreased to values close to control after 16 h. Total (lipids+proteins vs. protein-specific carbonylation showed different dynamics, with a significant increase in protein-bound carbonyls at later time points. Treatment with SIN-1 in combination with inhibitors of proteasomal and autophagy/lysosomal degradation pathways allowed confirmation of a significant role of the proteasome in the degradation of carbonylated proteins, whereas lipid carbonylation increased in the presence of autophagy/lysosomal inhibitors. Electrophilic aldehydes and ketones formed by lipid peroxidation were identified and relatively quantified using LC-MS/MS. Molecular identity of reactive species was used for data-driven analysis of their protein targets. Combination of different enrichment strategies with LC-MS/MS analysis allowed identification of more than 167 unique proteins with 332 sites modified by electrophilic lipid peroxidation products. Gene ontology analysis of modified proteins demonstrated enrichment of several functional categories including proteins involved in cytoskeleton, extracellular matrix, ion channels and their regulation. Using calcium mobilization assays, the effect of nitroxidative stress on the activity of several ion

  13. Scaling up carbonyl sulfide (COS) fluxes from leaf and soil to the canopy

    Science.gov (United States)

    Yang, Fulin; Yakir, Dan

    2016-04-01

    Carbonyl sulfide (COS) with atmospheric concentrations around 500 ppt is an analog of CO2 which can potentially serve as powerful and much needed tracer of photosynthetic CO2 uptake, and global gross primary production (GPP). However, questions remain regarding the application of this approach due to uncertainties in the contributions of different ecosystem components to the canopy scale fluxes of COS. We used laser quantum cascade spectroscopy in combination with soil and branch chambers, and eddy covariance measurements of net ecosystem exchange fluxes of COS and CO2 (NEE) in citrus orchard during the driest summer month to test our ability to integrate the chamber measurements into the ecosystem fluxes. The results indicated that: 1) Soil fluxes showed clear gradient from continuous uptake under the trees in wet soil of up to -4 pmol m-2s-1 (CO2 emission of ~0.5 umol m-2s-1) to emission in dry hot and exposed soil between rows of trees of up to +3 pmol m-2s-1 (CO2 emission of ~11 umol m-2s-1). In all cases a clear correlation between fluxes and soil temperature was observed. 2) At the leaf scale, midday uptake was ~5.5 pmol m-2s-1 (CO2 uptake of ~1.8 umol m-2s-1). Some nighttime COS uptake was observed in the citrus leaves consistent with nocturnal leaf stomatal conductance. Leaf relative uptake (LRU) of COS vs. CO2 was not constant over the diurnal cycle, but showed exponential correlation with photosynthetically active radiation (PAR) during the daytime. 3) At the canopy scale mid-day summer flux reached -12.0 pmol m-2s-1 (NEE ~6 umol m-2s-1) with the diurnal patterns of COS fluxes following those of CO2 fluxes during the daytime, but with small COS uptake fluxes maintained also during the night when significant CO2 emission fluxes were observed. The canopy-scale fluxes always indicated COS uptake, irrespective of the soil emission effects. GPP estimates were consistent with conventional indirect estimates based on NEE and nocturnal measurements. Scaling up

  14. Molecular complexes of tungsten oxotetrachloride with azomethins. Molekulyarnye kompleksy oksotetrakhlorida vol'frama s azometinami

    Energy Technology Data Exchange (ETDEWEB)

    Abramenko, Yu V; Garnovskij, A D; Abramenko, V A; Medvedeva, T E [Rostovskij-na-Donu Gosudarstvennyj Univ., Rostov-na-Donu (Russian Federation). Nauchno-Issledovatel' skij Inst. Fizicheskoj i Organicheskoj Khimii

    1992-09-01

    Series of new molecular complexes of tungsten oxotetrachloride with benza- and salicylalimines of equimolar compositions obtained. Substances are studied using element analysis, IR spectroscopy and conductometry. Octahedral structure of complexes with central atom coordination of benzalaniline molecules via azomethin nitrogen atom, and salicylalimines - via carbonyl oxygen atom of quinoid tantometric form of ligand is assumed.

  15. A Smart Europium-Ruthenium Complex as Anticancer Prodrug: Controllable Drug Release and Real-Time Monitoring under Different Light Excitations.

    Science.gov (United States)

    Li, Hongguang; Xie, Chen; Lan, Rongfeng; Zha, Shuai; Chan, Chi-Fai; Wong, Wing-Yan; Ho, Ka-Lok; Chan, Brandon Dow; Luo, Yuxia; Zhang, Jing-Xiang; Law, Ga-Lai; Tai, William C S; Bünzli, Jean-Claude G; Wong, Ka-Leung

    2017-11-09

    A unique, dual-function, photoactivatable anticancer prodrug, RuEuL, has been tailored that features a ruthenium(II) complex linked to a cyclen-europium chelate via a π-conjugated bridge. Under irradiation at 488 nm, the dark-inactive prodrug undergoes photodissociation, releasing the DNA-damaging ruthenium species. Under evaluation-window irradiation (λ irr = one-photon 350 nm or two-photon 700 nm), the drug delivery process can be quantitatively monitored in real-time because of the long-lived red europium emission. Linear relationships between released drug concentration and ESI-MS or luminescence responses are established. Finally, the efficiency of the new prodrug is demonstrated both in vitro RuEuL anticancer prodrug over some existing ones and open the way for decisive improvements in multipurpose prodrugs.

  16. The Drosophila carbonyl reductase sniffer is an efficient 4-oxonon-2-enal (4ONE) reductase.

    Science.gov (United States)

    Martin, Hans-Jörg; Ziemba, Marta; Kisiela, Michael; Botella, José A; Schneuwly, Stephan; Maser, Edmund

    2011-05-30

    Studies with the fruit-fly Drosophila melanogaster demonstrated that the enzyme sniffer prevented oxidative stress-induced neurodegeneration. Mutant flies overexpressing sniffer had significantly extended life spans in a 99.5% oxygen atmosphere compared to wild-type flies. However, the molecular mechanism of this protection remained unclear. Sequence analysis and database searches identified sniffer as a member of the short-chain dehydrogenase/reductase superfamily with a 27.4% identity to the human enzyme carbonyl reductase type I (CBR1). As CBR1 catalyzes the reduction of the lipid peroxidation products 4HNE and 4ONE, we tested whether sniffer is able to metabolize these lipid derived aldehydes by carbonyl reduction. To produce recombinant enzyme, the coding sequence of sniffer was amplified from a cDNA-library, cloned into a bacterial expression vector and the His-tagged protein was purified by Ni-chelate chromatography. We found that sniffer catalyzed the NADPH-dependent carbonyl reduction of 4ONE (K(m)=24±2 μM, k(cat)=500±10 min(-1), k(cat)/K(m)=350 s(-1) mM(-1)) but not that of 4HNE. The reaction product of 4ONE reduction by sniffer was mainly 4HNE as shown by HPLC- and GC/MS analysis. Since 4HNE, though still a potent electrophile, is less neurotoxic and protein reactive than 4ONE, one mechanism by which sniffer exerts its neuroprotective effects in Drosophila after oxidative stress may be enzymatic reduction of 4ONE. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  17. Carbonyl Stress and Microinflammation-Related Molecules as Potential Biomarkers in Schizophrenia

    Directory of Open Access Journals (Sweden)

    Tohru Ohnuma

    2018-03-01

    Full Text Available This literature review primarily aims to summarize our research, comprising both cross-sectional and longitudinal studies, and discuss the possibility of using microinflammation-related biomarkers as peripheral biomarkers in the diagnosis and monitoring of patients with schizophrenia. To date, several studies have been conducted on peripheral biomarkers to recognize the potential markers for the diagnosis of schizophrenia and to determine the state and effects of therapy in patients with schizophrenia. Research has established a correlation between carbonyl stress, an environmental factor, and the pathophysiology of neuropsychiatric diseases, including schizophrenia. In addition, studies on biomarkers related to these stresses have achieved results that are either replicable or exhibit consistent increases or decreases in patients with schizophrenia. For instance, pentosidine, an advanced glycation end product (AGE, is considerably elevated in patients with schizophrenia; however, low levels of vitamin B6 [a detoxifier of reactive carbonyl compounds (RCOs] have also been reported in some patients with schizophrenia. Another study on peripheral markers of carbonyl stress in patients with schizophrenia revealed a correlation of higher levels of glyceraldehyde-derived AGEs with higher neurotoxicity and lower levels of soluble receptors capable of diminishing the effects of AGEs. Furthermore, studies on evoked microinflammation-related biomarkers (e.g., soluble tumor necrosis factor receptor 1 have reported relatively consistent results, suggesting the involvement of microinflammation in the pathophysiology of schizophrenia. We believe that our cross-sectional and longitudinal studies as well as various previous inflammation marker studies that could be interpreted from several perspectives, such as mild localized encephalitis and microvascular disturbance, highlighted the importance of early intervention as prevention and distinguished the possible

  18. A Simple Catalytic Mechanism for the Direct Coupling of α-Carbonyls with Functionalized Amines: A One-Step Synthesis of Plavix

    OpenAIRE

    Evans, Ryan W.; Zbieg, Jason R.; Zhu, Shaolin; Li, Wei; MacMillan, David W. C.

    2013-01-01

    The direct α-amination of ketones, esters, and aldehydes has been accomplished via copper catalysis. In the presence of catalytic copper(II) bromide, a diverse range of carbonyl and amine substrates undergo fragment coupling to produce synthetically useful α-amino substituted motifs. The transformation is proposed to proceed via a catalytically generated α-bromo carbonyl species; nucleophilic displacement of the bromide by the amine then delivers the α-amino carbonyl adduct while the catalyst...

  19. A green synthesis of α,β-unsaturated carbonyl compounds from glyceraldehyde acetonide

    Directory of Open Access Journals (Sweden)

    Cláudia O. Veloso

    2011-01-01

    Full Text Available The catalytic behavior of Cs-exchanged and Cs-impregnated zeolites (X and Y was studied using the Knoevenagel condensation between glyceraldehyde acetonide and ethyl acetoacetate in order to produce the corresponding α,β-unsaturated carbonyl compound that is an important intermediate for fine chemicals. The influence of reaction temperature, type of zeolite, and basicity of the sites on the catalytic behavior of the samples was evaluated. All zeolites were active for the studied reaction. The formation of the main condensation product was favored at lower reaction temperatures. Products of further condensations were also observed especially for samples that were only dried before catalytic test.

  20. Chemical reactions in organic monomolecular layers. Condensation of hydrazine on carbonyl functions

    International Nuclear Information System (INIS)

    Rosilio, Charles; Ruaudel-Teixier, Annie.

    1976-01-01

    Evidence is given for chemical reactions of hydrazine (NH 2 -NH 2 ) with different carbonyl functional groups of organic molecules in the solid state, in monomolecular layer structures. The condensation of hydrazine with these molecules leads to conjugated systems by bridging the N-N links, to cyclizations, and also to polycondensations. The reactions investigated were followed up by infrared spectrophotometry, by transmission and metallic reflection. These chemical reactions revealed in the solid phase constitute a polycondensation procedure which is valuable in obtaining organized polymers in monomolecular layers [fr

  1. Contribution of carbonyl photochemistry to aging of atmospheric secondary organic aerosol

    DEFF Research Database (Denmark)

    Mang, Stephen A.; Henricksen, Dana K.; Bateman, Adam P.

    2008-01-01

    of freshly prepared SOA was estimated to be on the order of' 15 L mol(-1) cm(-1) at 300 rim, implying one carbonyl group in every SOA constituent. The absorption by the SOA material slowly increased in the visible and near-UV during storage of SOA in open air in the dark, presumably as a result......The photodegradation of secondary organic aerosol (SOA) material by actinic UV radiation was investigated. SOA was generated via the dark reaction of ozone and d-limonene, collected onto quartz-fiber filters, and exposed to wavelength-tunable radiation. Photochemical production of CO was monitored...

  2. Determination of carbonyl compounds in air by HPLC; Determinacion de compuestos carbonilicos en aire por HPLC

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, S; Perez, R M; Campos, A; Gonzalez, D

    1995-07-01

    A method for the determination of seven carbonyl compounds in air is presented. The procedure involve sampling of air by a Sep-Pak Cartridge impregnated with 2,4-dinitrophenylhydrazine. Elution was done with 3 mL of acetonitrile and the eluate was diluted to 5 mL. The analysis was done by HPLC with UV detection and external standard method quantification. It has been achieved relative standard deviations about 5% and detection limits of 80 ng/cartridge for formaldehyde, acetaldehyde and acetoacetonitrile. Three different types of samples (rural, urban, petrol emission) were successfully analyzed. (Author) 12 refs.

  3. 13C NMR investigation of the structure of cationic carbonyls in transition metal zeolites

    International Nuclear Information System (INIS)

    Ben Taarit, Y.

    1979-01-01

    13 C NMR spectroscopy was used to investigate the nature of carbon monoxide adsorbed on transition metal ions hosted in a synthetic faujastite type zeolite. The adsorbed CO species was characterised by a highly shielded carbon nucleus. Using the Pople approximation for the paramagnetic shielding term, the observed chemical shift was rationalised assuming the formation of a cationic carbonyl species with an appreciable electronic transfer from the carbon lone pair to the transition metal ion and negligible π back-bonding if at all. (Auth.)

  4. Organocatalyzed Asymmetric α-Oxidation, α-Aminoxylation and α-Amination of Carbonyl Compounds

    Directory of Open Access Journals (Sweden)

    Worawan Bhanthumnavin

    2010-02-01

    Full Text Available Organocatalytic asymmetric α-oxidation and amination reactions of carbonyl compounds are highly useful synthetic methodologies, especially in generating chiral building blocks that previously have not been easily accessible by traditional methods. The concept is relatively new and therefore the list of new catalysts, oxidizing and aminating reagents, as well as new substrates, are expanding at an amazing rate. The scope of this review includes new reactions and catalysts, mechanistic aspects and synthetic applications of α-oxidation, hydroxylation, aminoxylation, amination, hydrazination, hydroxyamination and related α-heteroatom functionalization of aldehydes, ketones and related active methylene compounds published during 2005–2009.

  5. Elevated Levels of Carbonyl Compounds in the Atmosphere of Eastern Himalaya in India

    Science.gov (United States)

    Sarkar, C.; Chatterjee, A.; Majumdar, D.; Raha, S.; Ghosh, S. K.; Srivastava, A.

    2015-12-01

    A first ever study on atmospheric carbonyl compounds (CC) were made over eastern Himalaya in India. Samples were collected over a high altitude hill station, Darjeeling (27.01°N, 88.15°E, 2200 masl) during 2011-2012. It is well known that CC have toxic and carcinogenic properties as well as they have important effects on regional climate. Therefore their presence in the environment is of great concern especially for the Himalayan region because of the ecological and geographical importance of the area. The average annual concentration of total CCs was 293.3 ± 463.9 μgm-3 with maximum during post monsoon (1104.8 ± 568.0 μgm-3) and minimum during winter season (72.2 ± 42.9 μgm-3). Darjeeling experiences huge emissions of carbonaceous pollutants from massive influx of tourists during premonsoon and postmonsoon seasons. Though the emission strength could be comparable, the loss of carbonyls from the atmosphere could be due to photochemical degradation under high solar insolation during premonsoon. Acetone was most abundant species with an annual average concentration of 200.8±352.9 μgm-3 with 70 % contribution to the total CCs measured. Interestingly, acetone over Darjeeling was found to be much higher than most of the metropolitan cities in the world. The average formaldehyde to acetaldehyde ratio (1.64 ± 1.43) over Darjeeling is a good representation of a typical urban atmosphere at this high altitude over this part of Himalaya. High carbonyl concentration over eastern Himalaya compared to other megacities across the globe could be attributed to uncontrolled activities related to development in tourism, high population density and moreover it's unique orography and land use pattern with narrow roads, unplanned township etc. The unscientific treatment of human and animal and other domestic waste is another major concern which significantly contribute to carbonyl and other carbonaceous pollutants over this part of Himalaya.

  6. A Device-Independent Evaluation of Carbonyl Emissions from Heated Electronic Cigarette Solvents.

    Directory of Open Access Journals (Sweden)

    Ping Wang

    Full Text Available To investigate how the two main electronic (e- cigarette solvents-propylene glycol (PG and glycerol (GL-modulate the formation of toxic volatile carbonyl compounds under precisely controlled temperatures in the absence of nicotine and flavor additives.PG, GL, PG:GL = 1:1 (wt/wt mixture, and two commercial e-cigarette liquids were vaporized in a stainless steel, tubular reactor in flowing air ranging up to 318°C to simulate e-cigarette vaping. Aerosols were collected and analyzed to quantify the amount of volatile carbonyls produced with each of the five e-liquids.Significant amounts of formaldehyde and acetaldehyde were detected at reactor temperatures ≥215°C for both PG and GL. Acrolein was observed only in e-liquids containing GL when reactor temperatures exceeded 270°C. At 318°C, 2.03±0.80 μg of formaldehyde, 2.35±0.87 μg of acetaldehyde, and a trace amount of acetone were generated per milligram of PG; at the same temperature, 21.1±3.80 μg of formaldehyde, 2.40±0.99 μg of acetaldehyde, and 0.80±0.50 μg of acrolein were detected per milligram of GL.We developed a device-independent test method to investigate carbonyl emissions from different e-cigarette liquids under precisely controlled temperatures. PG and GL were identified to be the main sources of toxic carbonyl compounds from e-cigarette use. GL produced much more formaldehyde than PG. Besides formaldehyde and acetaldehyde, measurable amounts of acrolein were also detected at ≥270°C but only when GL was present in the e-liquid. At 215°C, the estimated daily exposure to formaldehyde from e-cigarettes, exceeded United States Environmental Protection Agency (USEPA and California Office of Environmental Health Hazard Assessment (OEHHA acceptable limits, which emphasized the need to further examine the potential cancer and non-cancer health risks associated with e-cigarette use.

  7. Engineered Trx2p industrial yeast strain protects glycolysis and fermentation proteins from oxidative carbonylation during biomass propagation

    Directory of Open Access Journals (Sweden)

    Gómez-Pastor Rocío

    2012-01-01

    Full Text Available Abstract Background In the yeast biomass production process, protein carbonylation has severe adverse effects since it diminishes biomass yield and profitability of industrial production plants. However, this significant detriment of yeast performance can be alleviated by increasing thioredoxins levels. Thioredoxins are important antioxidant defenses implicated in many functions in cells, and their primordial functions include scavenging of reactive oxygen species that produce dramatic and irreversible alterations such as protein carbonylation. Results In this work we have found several proteins specifically protected by yeast Thioredoxin 2 (Trx2p. Bidimensional electrophoresis and carbonylated protein identification from TRX-deficient and TRX-overexpressing cells revealed that glycolysis and fermentation-related proteins are specific targets of Trx2p protection. Indeed, the TRX2 overexpressing strain presented increased activity of the central carbon metabolism enzymes. Interestingly, Trx2p specifically preserved alcohol dehydrogenase I (Adh1p from carbonylation, decreased oligomer aggregates and increased its enzymatic activity. Conclusions The identified proteins suggest that the fermentative capacity detriment observed under industrial conditions in T73 wine commercial strain results from the oxidative carbonylation of specific glycolytic and fermentation enzymes. Indeed, increased thioredoxin levels enhance the performance of key fermentation enzymes such as Adh1p, which consequently increases fermentative capacity.

  8. Characterization of selected volatile organic compounds, polycyclic aromatic hydrocarbons and carbonyl compounds at a roadside monitoring station

    Science.gov (United States)

    Ho, K. F.; Lee, S. C.; Chiu, Gloria M. Y.

    Volatile organic compounds (VOCs), PAHs and carbonyl compounds are the major toxic components in Hong Kong. Emissions from motor vehicles have been one of the primary pollution sources in the metropolitan areas throughout Hong Kong for a long time. A 1-yr monitoring program for VOCs, PAHs and carbonyl compounds had been performed at a roadside urban station at Hong Kong Polytechnic University in order to determine the variations and correlations of each selected species (VOCs, PAHs and carbonyl compounds). This study is aimed to analyze toxic volatile organic compounds (benzene, toluene, ethylbenzene and xylene), two carbonyl compounds (formaldehyde, acetaldehyde), and selective polycyclic aromatic hydrocarbons. The monitoring program started from 16 April 1999 to 30 March 2000. Ambient VOC concentrations, many of which originate from the same sources as particulate PAHs and carbonyls compounds, show significant quantities of benzene, toluene and xylenes. Correlations and multivariate analysis of selected gaseous and particulate phase organic pollutants were performed. Source identification by principle component analysis and hierarchical cluster analysis allowed the identification of four sources (factors) for the roadside monitoring station. Factor 1 represents the effect of diesel vehicle exhaust. Factor 2 shows the contribution of aromatic compounds. Factor 3 explains photochemical products—formaldehyde and acetaldehyde. Factor 4 explains the effect of gasoline vehicle exhaust.

  9. Carbonyl emission and toxicity profile of diesel blends with an animal-fat biodiesel and a tire pyrolysis liquid fuel.

    Science.gov (United States)

    Ballesteros, R; Guillén-Flores, J; Martínez, J D

    2014-02-01

    In this paper, two diesel fuels, an animal-fat biodiesel and two diesel blends with the animal-fat biodiesel (50vol.%) and with a tire pyrolysis liquid (TPL) fuel (5vol.%) have been tested in a 4-cylinder, 4-stroke, turbocharged, intercooled, 2.0L Nissan diesel automotive engine (model M1D) with common-rail injection system and diesel oxidation catalyst (DOC). Carbonyl emissions have been analyzed both before and after DOC and specific reactivity of carbonyl profile has been calculated. Carbonyl sampling was carried out by means of a heated line, trapping the gas in 2,4-DNPH cartridges. The eluted content was then analyzed in an HPLC system, with UV-VIS detection. Results showed, on the one hand, an increase in carbonyl emissions with the biodiesel fraction in the fuel. On the other hand, the addition of TPL to diesel also increased carbonyl emissions. These trends were occasionally different if the emissions were studied after the DOC, as it seems to be selectivity during the oxidation process. The specific reactivity was also studied, finding a decrease with the oxygen content within the fuel molecule, although the equivalent ozone emissions slightly increased with the oxygen content. Finally, the emissions toxicity was also studied, comparing them to different parameters defined by different organizations. Depending on the point of study, emissions were above or below the established limits, although acrolein exceeded them as it has the least permissive values. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Mono- and Dinuclear Manganese Carbonyls Supported by 1,8-Disubstituted (L = Py, SMe, SH) Anthracene Ligand Scaffolds.

    Science.gov (United States)

    Manes, Taylor A; Rose, Michael J

    2016-06-06

    Presented herein is a synthetic scheme to generate symmetric and asymmetric ligands based on a 1,8-disubstituted anthracene scaffold. The metal-binding scaffolds were prepared by aryl chloride activation of 1,8-dichloroanthracene using Suzuki-type couplings facilitated by [Pd(dba)2] as a Pd source; the choice of cocatalyst (XPhos or SPhos) yielded symmetrically or asymmetrically substituted scaffolds (respectively): namely, Anth-SMe2 (3), Anth-N2 (4), and Anth-NSMe (6). The ligands exhibit a nonplanar geometry in the solid state (X-ray), owing to steric hindrance between the anthracene scaffold and the coupled aryl units. To determine the flexibility and binding characteristics of the anthracene-based ligands, the symmetric scaffolds were complexed with [Mn(CO)5Br] to afford the mononuclear species [(Anth-SMe2)Mn(CO)3Br] (8) and [(Anth-N2)Mn(CO)3Br] (9), in which the donor moieties chelate the Mn center in a cis fashion. The asymmetric ligand Anth-NSMe (6) binds preferentially through the py moieties, affording the bis-ligated complex [(Anth-NSMe)2Mn(CO)3Br] (10), wherein the thioether-S donors remain unbound. Alternatively, deprotection of the thioether in 6 affords the free thiol ligand Anth-NSH (7), which more readily binds the Mn center. Complexation of 7 ultimately affords the mixed-valence Mn(I)/Mn(II) dimer of formula [(Anth-NS)3Mn2(CO)3] (11), which exhibits a fac-{Mn(CO)3} unit supported by a triad of bridging thiolates, which are in turn ligated to a supporting Mn(II) center (EPR: |D| = 0.053 cm(-1), E/|D| = 0.3, Aiso = -150 MHz). All of the metal complexes have been characterized by single-crystal X-ray diffraction, IR spectroscopy and NMR/EPR measurements-all of which demonstrate that the meta-linked, anthracene-based ligand scaffold is a viable approach for the coordination of metal carbonyls.

  11. The unusually strong hydrogen bond between the carbonyl of Q(A) and His M219 in the Rhodobacter sphaeroides reaction center is not essential for efficient electron transfer from Q(A)(-) to Q(B).

    Science.gov (United States)

    Breton, Jacques; Lavergne, Jérôme; Wakeham, Marion C; Nabedryk, Eliane; Jones, Michael R

    2007-06-05

    In native reaction centers (RCs) from photosynthetic purple bacteria the primary quinone (QA) and the secondary quinone (QB) are interconnected via a specific His-Fe-His bridge. In Rhodobacter sphaeroides RCs the C4=O carbonyl of QA forms a very strong hydrogen bond with the protonated Npi of His M219, and the Ntau of this residue is in turn coordinated to the non-heme iron atom. The second carbonyl of QA is engaged in a much weaker hydrogen bond with the backbone N-H of Ala M260. In previous work, a Trp side chain was introduced by site-directed mutagenesis at the M260 position in the RC of Rb. sphaeroides, resulting in a complex that is completely devoid of QA and therefore nonfunctional. A photochemically competent derivative of the AM260W mutant was isolated that contains a Cys side chain at the M260 position (denoted AM260(W-->C)). In the present work, the interactions between the carbonyl groups of QA and the protein in the AM260(W-->C) suppressor mutant have been characterized by light-induced FTIR difference spectroscopy of the photoreduction of QA. The QA-/QA difference spectrum demonstrates that the strong interaction between the C4=O carbonyl of QA and His M219 is lost in the mutant, and the coupled CO and CC modes of the QA- semiquinone are also strongly perturbed. In parallel, a band assigned to the perturbation of the C5-Ntau mode of His M219 upon QA- formation in the native RC is lacking in the spectrum of the mutant. Furthermore, a positive band between 2900 and 2400 cm-1 that is related to protons fluctuating within a network of highly polarizable hydrogen bonds in the native RC is reduced in amplitude in the mutant. On the other hand, the QB-/QB FTIR difference spectrum is essentially the same as for the native RC. The kinetics of electron transfer from QA- to QB were measured by the flash-induced absorption changes at 780 nm. Compared to native RCs the absorption transients are slowed by a factor of about 2 for both the slow phase (in the

  12. Electrochemical analysis of coordination sphere of ruthenium(II) as an electron transport mediator in glucose oxidase catalysis in aqueous solutions

    International Nuclear Information System (INIS)

    Kurova, V.S.; Ryabov, A.D.; Ershov, A.Yu.

    2001-01-01

    The redox-potentials of the cis-[Ru(LL) 2 XY] n+ complexes (LL=2,2' bipyridil, 1,10 phenanthrolin and 4,4'-dimethyl-2,2-bipyridil; X, Y = Cl - , Br - , CO 3 2- , No 2 - , SCN - , H 2 O and methylsulfoxide) in water solutions are measured through the cyclic voltamperometry method. The linear dependence of the ruthenium complexes(II) measured redox-potentials on the ligand sphere is established. It is shown, that these complexes manifest the properties of the reversible or quasi-reversible redox-systems, the formal redox-potential values whereof are within the 0.2-0.5 V interval [ru

  13. Toward Green Acylation of (Heteroarenes: Palladium-Catalyzed Carbonylation of Olefins to Ketones

    Directory of Open Access Journals (Sweden)

    Jie Liu

    2017-11-01

    Full Text Available Green Friedel–Crafts acylation reactions belong to the most desired transformations in organic chemistry. The resulting ketones constitute important intermediates, building blocks, and functional molecules in organic synthesis as well as for the chemical industry. Over the past 60 years, advances in this topic have focused on how to make this reaction more economically and environmentally friendly by using green acylating conditions, such as stoichiometric acylations and catalytic homogeneous and heterogeneous acylations. However, currently well-established methodologies for their synthesis either produce significant amounts of waste or proceed under harsh conditions, limiting applications. Here, we present a new protocol for the straightforward and selective introduction of acyl groups into (hetero­arenes without directing groups by using available olefins with inexpensive CO. In the presence of commercial palladium catalysts, inter- and intramolecular carbonylative C–H functionalizations take place with good regio- and chemoselectivity. Compared to classical Friedel–Crafts chemistry, this novel methodology proceeds under mild reaction conditions. The general applicability of this methodology is demonstrated by the direct carbonylation of industrial feedstocks (ethylene and diisobutene as well as of natural products (eugenol and safrole. Furthermore, synthetic applications to drug molecules are showcased.

  14. Carbonylation Modification Regulates Na/K-ATPase Signaling and Salt Sensitivity: A Review and a Hypothesis.

    Science.gov (United States)

    Shah, Preeya T; Martin, Rebecca; Yan, Yanling; Shapiro, Joseph I; Liu, Jiang

    2016-01-01

    Na/K-ATPase signaling has been implicated in different physiological and pathophysiological conditions. Accumulating evidence indicates that oxidative stress not only regulates the Na/K-ATPase enzymatic activity, but also regulates its signaling and other functions. While cardiotonic steroids (CTS)-induced increase in reactive oxygen species (ROS) generation is an intermediate step in CTS-mediated Na/K-ATPase signaling, increase in ROS alone also stimulates Na/K-ATPase signaling. Based on literature and our observations, we hypothesize that ROS have biphasic effects on Na/K-ATPase signaling, transcellular sodium transport, and urinary sodium excretion. Oxidative modulation, in particular site specific carbonylation of the Na/K-ATPase α1 subunit, is a critical step in proximal tubular Na/K-ATPase signaling and decreased transcellular sodium transport leading to increases in urinary sodium excretion. However, once this system is overstimulated, the signaling, and associated changes in sodium excretion are blunted. This review aims to evaluate ROS-mediated carbonylation of the Na/K-ATPase, and its potential role in the regulation of pump signaling and sodium reabsorption in the renal proximal tubule (RPT).

  15. Determination of carbonyl compounds (acetaldehyde and formaldehyde in polyethylene terephthalate containers designated for water conservation

    Directory of Open Access Journals (Sweden)

    Redžepović Azra S.

    2012-01-01

    Full Text Available Polyethylene terephthalate (PET has in the last several years become the main packaging material for many food products, particularly carbonated beverages and bottled water, as well as for products of chemical industry (packaging of various hygiene maintenance agents, pesticides, solvents, etc.. The strength and permeability properties of PET are very good for packaging of beverages, its resistance to chemicals is high and it has a high degree of transparency. Acetaldehyde and formaldehyde are formed during the thermoforming of PET containers. After cooling, acetaldehyde and formaldehyde remain trapped in the walls of a PET bottle and may migrate into the water after filling and storage. Since there are no migration tests in Serbia prescribed for the determination of acetaldehyde and formaldehyde, the purpose of the paper is to test the quantitative contents of carbonyl compounds (acetaldehyde and formaldehyde in PET containers of different volumes, made by various manufacturers of bottled mineral carbonated and noncarbonated water, and exposed to different temperatures. In this study, the migration of acetaldehyde and formaldehyde from PET bottles into mineral carbonated and noncarbonated water was determined by high performance liquid chromatography. Taking into consideration that formaldehyde and acetaldehyde have no UV active or fluorescent group, the chromatography shall be preceded by derivatization in a closed system (due to a low boiling point of acetaldehyde and formaldehyde, which shall transform carbonyl compounds into UV active compounds.

  16. Penicitroamide, an Antimicrobial Metabolite with High Carbonylization from the Endophytic Fungus Penicillium sp. (NO. 24).

    Science.gov (United States)

    Feng, Zi-Wei; Lv, Meng-Meng; Li, Xue-Shuang; Zhang, Liang; Liu, Cheng-Xiong; Guo, Zhi-Yong; Deng, Zhang-Shuang; Zou, Kun; Proksch, Peter

    2016-10-28

    Penicitroamide ( 1 ), a new metabolite with a new framework, was isolated from the ethyl acetate extract of the PDB (Potato Dextrose Broth) medium of Penicillium sp. (NO. 24). The endophytic fungus Penicillium sp. (NO. 24) was obtained from the healthy leaves of Tapiscia sinensis Oliv. The structure of penicitroamide ( 1 ) features a bicyclo[3.2.1]octane core unit with a high degree of carbonylization (four carbonyl groups and one enol group). The chemical structure of penicitroamide ( 1 ) was elucidated by analysis of 1D-, 2D-NMR and MS data. In bioassays, penicitroamide ( 1 ) displayed antibacterial potency against two plant pathogens, Erwinia carotovora subsp. Carotovora (Jones) Bersey, et al. and Sclerotium rolfsii Sacc. with MIC 50 at 45 and 50 μg/mL. Compound 1 also showed 60% lethality against brine shrimp at 10 μg/mL. Penicitroamide ( 1 ) exhibited no significant activity against A549, Caski, HepG2 and MCF-7 cells with IC 50 > 50 μg/mL. Finally, the possible biosynthetic pathway of penicitroamide ( 1 ) was discussed.

  17. Carbonylation as a key reaction in anaerobic acetone activation by Desulfococcus biacutus.

    Science.gov (United States)

    Gutiérrez Acosta, Olga B; Hardt, Norman; Schink, Bernhard

    2013-10-01

    Acetone is activated by aerobic and nitrate-reducing bacteria via an ATP-dependent carboxylation reaction to form acetoacetate as the first reaction product. In the activation of acetone by sulfate-reducing bacteria, acetoacetate has not been found to be an intermediate. Here, we present evidence of a carbonylation reaction as the initial step in the activation of acetone by the strictly anaerobic sulfate reducer Desulfococcus biacutus. In cell suspension experiments, CO was found to be a far better cosubstrate for acetone activation than CO2. The hypothetical reaction product, acetoacetaldehyde, is extremely reactive and could not be identified as a free intermediate. However, acetoacetaldehyde dinitrophenylhydrazone was detected by mass spectrometry in cell extract experiments as a reaction product of acetone, CO, and dinitrophenylhydrazine. In a similar assay, 2-amino-4-methylpyrimidine was formed as the product of a reaction between acetoacetaldehyde and guanidine. The reaction depended on ATP as a cosubstrate. Moreover, the specific activity of aldehyde dehydrogenase (coenzyme A [CoA] acylating) tested with the putative physiological substrate was found to be 153 ± 36 mU mg(-1) protein, and its activity was specifically induced in extracts of acetone-grown cells. Moreover, acetoacetyl-CoA was detected (by mass spectrometry) after the carbonylation reaction as the subsequent intermediate after acetoacetaldehyde was formed. These results together provide evidence that acetoacetaldehyde is an intermediate in the activation of acetone by sulfate-reducing bacteria.

  18. Comparative Proteomic Analysis of Carbonylated Proteins from the Striatum and Cortex of Pesticide-Treated Mice

    Directory of Open Access Journals (Sweden)

    Christina Coughlan

    2015-01-01

    Full Text Available Epidemiological studies indicate exposures to the herbicide paraquat (PQ and fungicide maneb (MB are associated with increased risk of Parkinson’s disease (PD. Oxidative stress appears to be a premier mechanism that underlies damage to the nigrostriatal dopamine system in PD and pesticide exposure. Enhanced oxidative stress leads to lipid peroxidation and production of reactive aldehydes; therefore, we conducted proteomic analyses to identify carbonylated proteins in the striatum and cortex of pesticide-treated mice in order to elucidate possible mechanisms of toxicity. Male C57BL/6J mice were treated biweekly for 6 weeks with saline, PQ (10 mg/kg, MB (30 mg/kg, or the combination of PQ and MB (PQMB. Treatments resulted in significant behavioral alterations in all treated mice and depleted striatal dopamine in PQMB mice. Distinct differences in 4-hydroxynonenal-modified proteins were observed in the striatum and cortex. Proteomic analyses identified carbonylated proteins and peptides from the cortex and striatum, and pathway analyses revealed significant enrichment in a variety of KEGG pathways. Further analysis showed enrichment in proteins of the actin cytoskeleton in treated samples, but not in saline controls. These data indicate that treatment-related effects on cytoskeletal proteins could alter proper synaptic function, thereby resulting in impaired neuronal function and even neurodegeneration.

  19. Synthesis of dimethyl carbonate (DMC) by oxidative carbonylation of methanol using polymer-supported CuCl{sub 2} catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Y. [Daicel Chemical Industries, Ltd., Hyogo (Japan). Research Center; Kobe University, Kobe (Japan); Kagotani, M. [Daicel Chemical Industries, Ltd., Hyogo (Japan). Research Center; Soma, Y. [Osaka National Research Institute, Osaka (Japan)

    2000-01-01

    Polymer, including 2,2'-bipyridine, poly(4-methyl-4'-vinyl-2,2'-bipyridine)(Pvbpy), was investigated for the synthesis of dimethyl carbonate (DMC) as a support for CuCl{sub 2}, by oxidative carbonylation of methanol in the liquid-phase. The CuCl{sub 2} complex (Pvbpy-CuCl{sub 2}) was insoluble in methanol, and the reaction system was heterogeneous. The Pvbpy-CuCl{sub 2} catalyst showed considerable catalytic activity (DMC yield: 44.4 % and DMC selectivity: 9206 %, at methanol conversion: 1.79 %), which is comparable to the previously reported data of poly (vinylpyridine) (PVP)-CuCl{sub 2} catalyst; the Pvbpy-CuCl{sub 2} catalyst could be recycled after filtration and washing thrice, provided, not having lost activity. The corrosion originating from Cl{sup -} was greatly improved by immobilizing the CuCl{sub 2} by Pvbpy. Elimination of CuCl{sub 2} from the Pvbpy support was observed during the reaction. In the first reaction, about 38 % of the initially supported Cl was released, and in the second and the third reactions, most of the Cl was retained. The rate of corrosion of stainless steels in the first use of the catalyst (0.6 mg h{sup -1} for HC276) was greater than that in the rate of the second and the third uses (<0.1 mg h{sup -1}). These results are closely related to the amount of Cl{sup -} released from the Pvbpy support, which demonstrates that the main cause of corrosion in the catalytic system is Cl{sup -} released from the Pvbpy-CuCl{sub 2} catalyst. From XPS study of the catalyst, it became obvious that Cu(2) was gradually reduced to Cu(1) during the reaction. (author)

  20. Sulfur isotopic analysis of carbonyl sulfide and its application for biogeochemical cycles

    Science.gov (United States)

    Hattori, Shohei; Kamezaki, Kazuki; Ogawa, Takahiro; Toyoda, Sakae; Katayama, Yoko; Yoshida, Naohiro

    2016-04-01

    Carbonyl sulfide (OCS or COS) is the most abundant gas containing sulfur in the atmosphere, with an average mixing ratio of 500 p.p.t.v. in the troposphere. OCS is suggested as a sulfur source of the stratospheric sulfate aerosols (SSA) which plays an important role in Earth's radiation budget and ozone depletion. Therefore, OCS budget should be validated for prediction of climate change, but the global OCS budget is imbalance. Recently we developed a promising new analytical method for measuring the stable sulfur isotopic compositions of OCS using nanomole level samples: the direct isotopic analytical technique of on-line gas chromatography-isotope ratio mass spectrometry (GC-IRMS) using fragmentation ions S+ (Hattori et al., 2015). The first measurement of the δ34S value for atmospheric OCS coupled with isotopic fractionation for OCS sink reactions in the stratosphere (Hattori et al., 2011; Schmidt et al., 2012; Hattori et al., 2012) explains the reported δ34S value for background stratospheric sulfate, suggesting that OCS is a potentially important source for background (nonepisodic or nonvolcanic) stratospheric sulfate aerosols. This new method measuring δ34S values of OCS can be used to investigate OCS sources and sinks in the troposphere to better understand its cycle. It is known that some microorganisms in soil can degrade OCS, but the mechanism and the contribution to the OCS in the air are still uncertain. In order to determine sulfur isotopic enrichment factor of OCS during degradation via microorganisms, incubation experiments were conducted using strains belonging to the genera Mycobacterium, Williamsia and Cupriavidus, isolated from natural soil environments (Kato et al., 2008). As a result, sulfur isotope ratios of OCS were increased during degradation of OCS, indicating that reaction for OC32S is faster than that for OC33S and OC34S. OCS degradation via microorganisms is not mass-independent fractionation (MIF) process, suggesting that this

  1. The coordination chemistry of dipyridylbenzene: N-deficient terpyridine or panacea for brightly luminescent metal complexes?

    Science.gov (United States)

    Williams, J A Gareth

    2009-06-01

    1,3-Di(2-pyridyl)benzene (dpybH) structurally resembles the widely-used ligand terpyridine (tpy), with which it is isoelectronic. In this critical review, following a brief overview of synthetic strategies for dpybH and derivatives, we survey the different types of complex that are possible with these ligands. Whilst metals such as ruthenium(ii), osmium(ii) and platinum(ii) give a terdentate N--C--N binding mode in which cyclometallation occurs at C(2), the ions iridium(iii), rhodium(iii) and palladium(ii) favour C(4) metallation. The latter process can be blocked by appropriate ligand modification, to allow the N--C--N mode to be accessed with these metal ions too. The luminescence properties of the complexes are discussed. A huge range of emission efficiencies are encountered amongst Ir(iii) complexes containing dpyb derivatives, according to the other ligands present. Trends can be rationalised with the aid of simple frontier-orbital considerations. The Pt(ii) complexes of dipyridylbenzenes are also intensely luminescent. Their application to contemporary organic light-emitting device (OLED) technology is discussed, including white light emitters exploiting excimer emission. Their potential as cell imaging agents amenable to time-resolved detection procedures on the microsecond timescale has also been demonstrated (118 references).

  2. Gas/particle partitioning of carbonyls in the photooxidation of isoprene and 1,3,5-trimethylbenzene

    Directory of Open Access Journals (Sweden)

    R. M. Healy

    2008-06-01

    Full Text Available A new denuder-filter sampling technique has been used to investigate the gas/particle partitioning behaviour of the carbonyl products from the photooxidation of isoprene and 1,3,5-trimethylbenzene. A series of experiments was performed in two atmospheric simulation chambers at atmospheric pressure and ambient temperature in the presence of NOx and at a relative humidity of approximately 50%. The denuder and filter were both coated with the derivatizing agent O-(2,3,4,5,6-pentafluorobenzyl-hydroxylamine (PFBHA to enable the efficient collection of gas- and particle-phase carbonyls respectively. The tubes and filters were extracted and carbonyls identified as their oxime derivatives by GC-MS. The carbonyl products identified in the experiments accounted for around 5% and 10% of the mass of secondary organic aerosol formed from the photooxidation of isoprene and 1,3,5-trimethylbenzene respectively.

    Experimental gas/particle partitioning coefficients were determined for a wide range of carbonyl products formed from the photooxidation of isoprene and 1,3,5-trimethylbenzene and compared with the theoretical values based on standard absorptive partitioning theory. Photooxidation products with a single carbonyl moiety were not observed in the particle phase, but dicarbonyls, and in particular, glyoxal and methylglyoxal, exhibited gas/particle partitioning coefficients several orders of magnitude higher than expected theoretically. These findings support the importance of heterogeneous and particle-phase chemical reactions for SOA formation and growth during the atmospheric degradation of anthropogenic and biogenic hydrocarbons.

  3. Investigation of carbonyl compound sources at a rural site in the Yangtze River Delta region of China.

    Science.gov (United States)

    Wang, Ming; Chen, Wentai; Shao, Min; Lu, Sihua; Zeng, Limin; Hu, Min

    2015-02-01

    Carbonyl compounds are important intermediates in atmospheric photochemistry, but their primary sources are still not understood well. In this work, carbonyls, hydrocarbons, and alkyl nitrates were continuously measured during November 2011 at a rural site in the Yangtze River Delta region of China. Mixing ratios of carbonyls and hydrocarbons showed large fluctuations during the entire measurement. The average level for total measured volatile organic compounds during the pollution episode from 25th to 27th November, 2011 was 91.6 ppb, about 7 times the value for the clean period of 7th-8th, November, 2011. To preliminarily identify toluene sources at this site, the emission ratio of toluene to benzene (T/B) during the pollution episode was determined based on photochemical ages derived from the relationship of alkyl nitrates to their parent alkanes. The calculated T/B was 5.8 ppb/ppb, significantly higher than the values of 0.2-1.7 ppb/ppb for vehicular exhaust and other combustion sources, indicating the dominant influence of industrial emissions on ambient toluene. The contributions of industrial sources to ambient carbonyls were then calculated using a multiple linear regression fit model that used toluene and alkyl nitrates as respective tracers for industrial emission and secondary production. During the pollution episode, 18.5%, 69.0%, and 52.9% of measured formaldehyde, acetaldehyde, and acetone were considered to be attributable to industrial emissions. The emission ratios relative to toluene for formaldehyde, acetaldehyde, and acetone were determined to be 0.10, 0.20 and 0.40 ppb/ppb, respectively. More research on industrial carbonyl emission characteristics is needed to understand carbonyl sources better. Copyright © 2014. Published by Elsevier B.V.

  4. Kinetics and Mechanism of the Gas-Phase Reaction of Selected Carbonyls with Cl Atoms between 250 and 340 K

    Science.gov (United States)

    Hasson, A. S.; Algrim, L.; Abdelhamid, A.; Tyndall, G. S.; Orlando, J. J.

    2013-12-01

    Carbonyls are important products from the gas phase degradation of most volatile organic compounds. Their atmospheric reactions therefore have a significant impact on atmospheric composition, particularly in aged air masses. While the reactions of short-chain linear carbonyls are well understood, the chemistry of larger (> C6) and branched carbonyl is more uncertain. To provide insight into these reactions, the reactions of three carbonyls (methyl isopropyl ketone, MIK; di-isopropyl ketone, DIK; and diethyl ketone, DEK) with chlorine atoms were investigated between 250 and 340 K and 1 atm in the presence and absence of NOx and an HO2 source (methanol). Experiments were performed in a photochemical reactor using a combination of long-path Fourier transform infra-red spectroscopy, proton transfer reaction mass spectrometry and gas chromatography with flame ionization detection. The kinetics were studied using the relative rate technique with butanone and isopropanol as the reference compounds. The Arrhenius expression for the three rate coefficients was determined to be k(DEK+Cl) = 3.87 x 10-11e(2 × 7 kJ/mol)/RT cm3 molecules-1 s-1 , k(MIPK+Cl) = 7.20 x 10-11e(0.2× 8 kJ/mol)/RT cm3 molecules-1 s-1 , and k(DIPK+Cl) = 3.33 x 10-10e(-3× 8 kJ/mol)/RT cm3 molecules-1 s-1 . Measured reaction products accounted for 38-72 % of the reacted carbon and were consistent with strong deactivation of the carbon atom adjacent to the carbonyl group with respect to H-atom abstraction by Cl atoms. The product distributions also provide insight into radical recycling from the organic peroxy + HO2 reaction, and the relative rates of isomerization, fragmentation and reaction with O2 for carbonyl-containing alkoxy radicals. Implications of these results will be discussed.

  5. Application of vanadium incorporated phosphomolybdate supported on the modified kaolinin synthesis of diphenyl carbonate by oxidative carbonylation with phenol

    Directory of Open Access Journals (Sweden)

    Peng Meng

    2017-01-01

    Full Text Available Keggin-type molybdophosphoric acid, molybdophosphoric salt and vanadium incorporated molybdophosphoric salt supported on the modified kaolin (MK were investigated as redox co-catalysts for the oxidative carbonylation of phenol to diphenyl carbonate (DPC in the absence of solvent. The 20 wt.% of MnAMPV5 (one kind of vanadium incorporated molybdophosphoric salt loaded on MK showed the highest catalytic activity with the yield of 24.68% and a TON of 306, while the selectivity amounts to nearly 100% in all the carbonylation reactions. The catalysts were characterized by XRD, BET, XPS and H2-TPR. The reusability study showed that the catalysts were stable and active.

  6. Determination of gaseous and particulate carbonyls (glycolaldehyde, hydroxyacetone, glyoxal, methylglyoxal, nonanal and decanal in the atmosphere at Mt. Tai

    Directory of Open Access Journals (Sweden)

    K. Kawamura

    2013-05-01

    Full Text Available Gaseous and particulate semi-volatile carbonyl compounds were determined every three hours in the atmosphere of Mount Tai (elevation, 1534 m in the North China Plain during 2–5, 23–24 and 25 June 2006 under clear sky conditions. Using a two-step filter cartridge in a series, particulate carbonyls were first collected on a quartz filter and then gaseous carbonyls were collected on a quartz filter impregnated with O-benzylhydroxylamine (BHA. After the two-step derivatization with BHA and N,O-Bis(trimethylsilyltrifluoroacetamide (BSTFA, carbonyl derivatives were measured using a gas chromatography. The gaseous concentrations were obtained as follow: glycolaldehyde (range 0–826 ng m−3, average 303 ng m−3, hydroxyacetone (0–579 ng m−3, 126 ng m−3, glyoxal (46–1200 ng m−3, 487 ng m−3, methylglyoxal (88–2690 ng m−3, 967 ng m−3, n-nonanal (0–500 ng m−3, 89 ng m−3, and n-decanal (0–230 ng m−3, 39 ng m−3. These concentrations are among the highest ever reported in the urban and forest atmosphere. We found that gaseous α-dicarbonyls (glyoxal and methylglyoxal are more than 20 times more abundant than particulate carbonyls and that glycolaldehyde is one order of magnitude more abundant than in aerosol phase. In contrast, hydroxyacetone and normal aldehydes (nonanal and decanal are equally present in both phases. Time-resolved variations of carbonyls did not show any a clear diurnal pattern, except for hydroxyacetone. We found that glyoxal, methylglyoxal and glycolaldehyde positively correlated with levoglucosan (a tracer of biomass burning, suggesting that a contribution from field burning of agricultural wastes (wheat crops is significant for the bifunctional carbonyls in the atmosphere of Mt. Tai. Upward transport of the pollutants to the mountaintop from the low lands in the North China Plain is a major process to control the distributions of carbonyls in the upper atmosphere over Mt. Tai.

  7. Reactions of carbonyl compounds with α,β-unsaturated nitriles as a convenient pathway to carbo- and heterocycles

    International Nuclear Information System (INIS)

    Sharanin, Yu A; Goncharenko, M P; Litvinov, Victor P

    1998-01-01

    Published data on the methods for synthesis of carbo- and heterocyclic compounds based on reactions of α,β-unsaturated nitriles with carbonyl compounds and activated phenols are surveyed. It is demonstrated that all these reactions occur via nucleophilic addition of the carbanion generated from a carbonyl compound to the double bond of an unsaturated nitrile (the Michael reaction). The main routes of transformation of the adducts into carbo- and heterocyclic compounds are considered. The methods for regioselective preparation of fused 4H-pyrans or 1,4-dihydropyridines by varying conditions of cyclisation of Michael adducts are discussed. The bibliography includes 249 references.

  8. Microwave electromagnetic properties of carbonyl iron particles and Si/C/N nano-powder filled epoxy-silicone coating

    International Nuclear Information System (INIS)

    Qing Yuchang; Zhou Wancheng; Luo Fa; Zhu Dongmei

    2010-01-01

    The electromagnetic characteristics of carbonyl iron particles and Si/C/N nano-powder filled epoxy-silicone coatings were studied. The reflection loss of the coatings exceeds -10 dB at 8-18 GHz and -9 dB at 2-18 GHz when the coating thickness is 1 and 3 mm, respectively. The dielectric and magnetic absorbers filled coatings possess excellent microwave absorption, which could be attributed to the proper incorporate of the multi-polarization mechanisms as well as strong natural resonance. It is feasible to develop the thin and wideband microwave absorbing coatings using carbonyl iron particles and Si/C/N nano-powder.

  9. Microwave electromagnetic properties of carbonyl iron particles and Si/C/N nano-powder filled epoxy-silicone coating

    Science.gov (United States)

    Qing, Yuchang; Zhou, Wancheng; Luo, Fa; Zhu, Dongmei

    2010-02-01

    The electromagnetic characteristics of carbonyl iron particles and Si/C/N nano-powder filled epoxy-silicone coatings were studied. The reflection loss of the coatings exceeds -10 dB at 8-18 GHz and -9 dB at 2-18 GHz when the coating thickness is 1 and 3 mm, respectively. The dielectric and magnetic absorbers filled coatings possess excellent microwave absorption, which could be attributed to the proper incorporate of the multi-polarization mechanisms as well as strong natural resonance. It is feasible to develop the thin and wideband microwave absorbing coatings using carbonyl iron particles and Si/C/N nano-powder.

  10. Copper-catalyzed oxidative desulfurization-oxygenation of thiocarbonyl compounds using molecular oxygen: an efficient method for the preparation of oxygen isotopically labeled carbonyl compounds.

    Science.gov (United States)

    Shibahara, Fumitoshi; Suenami, Aiko; Yoshida, Atsunori; Murai, Toshiaki

    2007-06-21

    A novel copper-catalyzed oxidative desulfurization reaction of thiocarbonyl compounds, using molecular oxygen as an oxidant and leading to formation of carbonyl compounds, has been developed, and the utility of the process is demonstrated by its application to the preparation of a carbonyl-18O labeled sialic acid derivative.

  11. On the Reaction of Carbonyl Diphosphonic Acid with Hydroxylamine and O-alkylhydroxylamines: Unexpected Degradation of P-C-P Bridge.

    Science.gov (United States)

    Khomich, Olga A; Yanvarev, Dmitry V; Novikov, Roman A; Kornev, Alexey B; Puljulla, Elina; Vepsäläinen, Jouko; Khomutov, Alex R; Kochetkov, Sergey N

    2017-06-23

    Derivatives of methylenediphosphonic acid possess wide spectra of biological activities and are used in enzymology as research tools as well as in practical medicine. Carbonyl diphosphonic acid is a promising starting building block for synthesis of functionally substituted methylenediphosphonates. Investigation of the interaction of carbonyl diphosphonic acid with hydroxylamine clearly demonstrates that it is impossible to isolate oxime within the pH range 2-12, while only cyanophosphonic and phosphoric acids are the products of the fast proceeding Beckmann-like fragmentation. In the case of O -alkylhydroxylamines, corresponding alcohols are found in the reaction mixtures in addition to cyanophosphonic and phosphoric acids. Therefore, two residues of phosphonic acid being attached to a carbonyl group provide new properties to this carbonyl group, making its oximes very unstable. This principally differs carbonyl diphosphonic acid from structurally related phosphonoglyoxalic acid and other α-ketophosphonates.

  12. Catalytic synthesis of aromatic diisocyanates by means of carbonylation of nitrocompounds with carbon monoxide

    Energy Technology Data Exchange (ETDEWEB)

    Nefedov, B K; Manov-Yuvenskii, V I; Khoshdurdev, Kh O; Novikov, S S [AN SSSR, Moscow. Inst. Organicheskoj Khimii

    1977-02-11

    The development of an active and selective heterogeneous catalyst for synthesis of aromatic diisocyanates has been studied. The catalytic ability of the catalyst PdO-MoO/sub 3/-Fe/sub 2/O/sub 3/ deposited on ..gamma..-Al/sub 2/O/sub 3/ has been investigated in the reactions of carbonylation of aromatic dinitrocompounds with carbon oxide. The effect of the catalyst composition, method of catalyst production, reaction temperature and pressure on the catalytic ability have been studied. It has been established that the catalyst PdO-MoO/sub 3/-Fe/sub 2/O/sub 3/(2-6:1:1) deposited on ..gamma..-Al/sub 2/O/sub 3/ is highly active and selective in the reactions of carbonilation of aromatic dinitrocompounds at 210 deg and 300 atm. It has been used for synthesis of aromatic diisocyanates in yield 32-75%.

  13. Synthesis and Characterization of Low Solubility Poly Carbonyl Urea as a Slow Release Fertilizer

    International Nuclear Information System (INIS)

    Liu, Y.; Sun, X.

    2016-01-01

    Low solubility poly carbonyl urea has been successfully synthesized by the reaction of urea with methyl carbamate (MC) under the conditions of potassium carbonate as an initiator. It was characterized by FT-IR, /sup 13/C-NMR, and elemental analyser. In addition, the influences of the quantity of initiator, reaction temperature, reaction time and the molar ratio of starting materials on the conversion are discussed in detail. All those observations suggest that when initiator as 10 wt percent of urea, the reaction temperature 160 Degree C, 6 h, and n(urea):n(MC)=1:10, the reaction conversion rate can reach 78.4 percent. Moreover, the novel procedure is reported for the first time and has a significant N slow release properties, the N release in soil was 80 percent over 30 days. (author)

  14. Protonation Sites, Tandem Mass Spectrometry and Computational Calculations of o-Carbonyl Carbazolequinone Derivatives.

    Science.gov (United States)

    Martínez-Cifuentes, Maximiliano; Clavijo-Allancan, Graciela; Zuñiga-Hormazabal, Pamela; Aranda, Braulio; Barriga, Andrés; Weiss-López, Boris; Araya-Maturana, Ramiro

    2016-07-05

    A series of a new type of tetracyclic carbazolequinones incorporating a carbonyl group at the ortho position relative to the quinone moiety was synthesized and analyzed by tandem electrospray ionization mass spectrometry (ESI/MS-MS), using Collision-Induced Dissociation (CID) to dissociate the protonated species. Theoretical parameters such as molecular electrostatic potential (MEP), local Fukui functions and local Parr function for electrophilic attack as well as proton affinity (PA) and gas phase basicity (GB), were used to explain the preferred protonation sites. Transition states of some main fragmentation routes were obtained and the energies calculated at density functional theory (DFT) B3LYP level were compared with the obtained by ab initio quadratic configuration interaction with single and double excitation (QCISD). The results are in accordance with the observed distribution of ions. The nature of the substituents in the aromatic ring has a notable impact on the fragmentation routes of the molecules.

  15. Microbial carbonylation and hydroxylation of 20(R)-panaxadiol by Aspergillus niger.

    Science.gov (United States)

    Yan, Bin; Chen, Zhihua; Zhai, Xuguang; Yin, Guibo; Ai, Yafei; Chen, Guangtong

    2018-04-01

    20(R)-panaxadiol (PD) was metabolised by the fungus Aspergillus niger AS 3.3926 to its C-3 carbonylated metabolite and five other hydroxylated metabolites (1-6). Their structures were elucidated as 3-oxo-20(R)-panaxadiol (1), 3-oxo-7β-hydroxyl- 20(R)-panaxadiol (2), 3-oxo-7β,23α-dihydroxyl-20(R)-panaxadiol (3), 3,12-dioxo- 7β,23β-dihydroxyl-20(R)-panaxadiol (4), 3-oxo-1α,7β-dihydroxyl-20(R)-panaxadiol (5) and 3-oxo-7β,15β-dihydroxyl-20(R)-panaxadiol (6) by spectroscopic analysis. Among them, compounds 2-6 were new compounds. Pharmacological studies revealed that compound 6 exhibited significant anti-hepatic fibrosis activity.

  16. Magnetomechanical properties of composites and fibers made from thermoplastic elastomers (TPE) and carbonyl iron powder (CIP)

    Science.gov (United States)

    Schrödner, Mario; Pflug, Günther

    2018-05-01

    Magnetoactive elastomers (MAE) made from composites of five thermoplastic elastomers (TPE) of different stiffness with carbonyl iron powder (CIP) as magnetic component were investigated. The composites were produced by melt blending of the magnetic particles with the TPEs in a twin-screw extruder. The resulting materials were characterized by ac permeability testing, stress-strain measurements with and without external magnetic field and magnetically controlled bending of long cylindrical rods in a homogenous magnetic field. The magnetic field necessary for deflection of the rods decreases with decreasing modulus and increasing iron particle content. This effect can be used e.g. for magnetically controlled actuation. Some highly filled MAE show a magnetic field induced increase of Young's modulus. Filaments could be spun from some of the composites.

  17. Magnetoelectric behavior of carbonyl iron mixed Mn oxide-coated ferrite nanoparticles

    Science.gov (United States)

    Ahad, Faris B. Abdul; Lee, Shang-Fan; Hung, Dung-Shing; Yao, Yeong-Der; Yang, Ruey-Bin; Lin, Chung-Kwei; Tsay, Chien-Yie

    2010-05-01

    The dielectric and magnetic properties of manganese oxide-coated Fe3O4 nanoparticles (NPs) were measured by the cavity perturbation method at x-band microwave frequencies ranging from 7-12.5 GHz with controlled external magnetic field up to 2.2 kOe at room temperature. Different ratios (5%, 10%, and 20% by weight) of coated NPs were prepared by sol-gel method then mixed with carbonyl iron powder in epoxy matrix. The saturation magnetization is inversely proportional to the NPs ratio in the mixture between 150 and 180 emu/g. The real part of the permittivity decreased with increasing NPs concentration, but the permittivity change by magnetic field increased. The tunability behavior is explained by insulator-ferromagnetic interface magnetoelectricity and the large surface volume ratio for the NPs.

  18. Serum levels of carbonylated and nitrosylated proteins in mobbing victims with workplace adjustment disorders.

    Science.gov (United States)

    Di Rosa, A E; Gangemi, S; Cristani, M; Fenga, C; Saitta, S; Abenavoli, E; Imbesi, S; Speciale, A; Minciullo, P L; Spatari, G; Abbate, S; Saija, A; Cimino, F

    2009-12-01

    Today the most important problem in the work place is psychological abuse, which may affect the health because of high levels of stress and anxiety. There is evidence that most psychiatric disorders are associated with increased oxidative stress but nothing is reported about the presence of oxidative stress in mobbing victims. This study has been carried out in a group of 19 patients affected by workplace mobbing-due adjustment disorders, in comparison with 38 healthy subjects, to evaluate whether oxidative stress may be induced by mobbing. Serum levels of protein carbonyl groups and of nitrosylated proteins, biological markers of oxidative stress conditions, were higher than those measured in healthy subjects. These findings may contribute to a better understanding of the redox homeostasis dysregulation occurring in victims of workplace mobbing.

  19. Temporal variation of carbonyl compound concentrations at a semi-rural site in Denmark

    DEFF Research Database (Denmark)

    Christensen, C.S.; Skov, H.; Nielsen, T.

    2000-01-01

    The atmospheric concentrations of formaldehyde, acetaldehyde and acetone were measured by the DNPH-technique at the semi-rural site Lille Valby, Denmark (55 degrees N) between May-July 1995, The average concentrations were observed to be 1.2 ppbv for formaldehyde, 0.8 ppbv for acetaldehyde and 1.......9 ppbv for acetone, For the set of carbonyl compounds, concentrations were found to be highly correlated, though only during daytime, The weak correlations observed during nighttime are believed to be caused by the dry deposition of especially formaldehyde, During periods with low photochemical activity...... of hydrocarbons during long-range transport. Especially, the concentration levels of acetone showed a pronounced seasonal-variation with the highest levels observed during summertime and lowest in winter and spring. The seasonal variation in the concentration levels of formaldehyde and acetaldehyde were small...

  20. Solution-Processable Balanced Ambipolar Field-Effect Transistors Based on Carbonyl-Regulated Copolymers.

    Science.gov (United States)

    Yang, Chengdong; Fang, Renren; Yang, Xiongfa; Chen, Ru; Gao, Jianhua; Fan, Hanghong; Li, Hongxiang; Hu, Wenping

    2018-04-04

    It is very important to develop ambipolar field effect transistors to construct complementary circuits. To obtain balanced hole- and electron-transport properties, one of the key issues is to regulate the energy levels of the frontier orbitals of the semiconductor materials by structural tailoring, so that they match well with the electrode Fermi levels. Five conjugated copolymers were synthesized and exhibited low LUMO energy levels and narrow bandgaps on account of the strong electron-withdrawing effect of the carbonyl groups. Polymer thin film transistors were prepared by using a solution method and exhibited high and balanced hole and electron mobility of up to 0.46 cm 2  V -1  s -1 , which suggested that these copolymers are promising ambipolar semiconductor materials. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Inactivation of cellular enzymes by carbonyls and protein-bound glycation/glycoxidation products

    DEFF Research Database (Denmark)

    Morgan, Philip E; Dean, Roger T; Davies, Michael Jonathan

    2002-01-01

    products. In this study, we have examined the effect of glucose and carbonyl compounds (methylglyoxal, glyoxal, glycolaldehyde, and hydroxyacetone), and glycation products arising from reaction of these materials with model proteins, on the activity of three key cellular enzymes: glyceraldehyde-3-phosphate...... dehydrogenase (GAPDH), glutathione reductase, and lactate dehydrogenase, both in isolation and in cell lysates. In contrast to glucose (1M, both fresh and aged for 8 weeks), which had no effect, marked inhibition of all three enzymes was observed with methylglyoxal and glyoxal. GAPDH was also inhibited...... by glycolaldehyde and hydroxyacetone. Incubation of these enzymes with proteins that had been preglycated with methylglyoxal, but not glucose, also resulted in significant time- and concentration-dependent inhibition with both isolated enzymes and cell lysates. This inhibition was not metal ion, oxygen, superoxide...

  2. Selectivity control of carbonylation of methanol to dimethyl oxalate and dimethyl carbonate over gold anode by electrochemical potential.

    Science.gov (United States)

    Funakawa, Akiyasu; Yamanaka, Ichiro; Takenaka, Sakae; Otsuka, Kiyoshi

    2004-05-05

    New and unique electrocatalysis of gold for the carbonylation of methanol to dimethyl oxalate (DMO) and dimethyl carbonate (DMC) was found. The selectivity to DMO and DMC could be controlled over gold anode by electrochemical potential, as you like. Drastic changes of gold electrocatalysis was due to changes of the oxidation state of gold, Au0 or Au3+.

  3. Palladium-catalyzed domino C,N-coupling/carbonylation/Suzuki coupling reaction: an efficient synthesis of 2-aroyl-/heteroaroylindoles.

    Science.gov (United States)

    Arthuis, Martin; Pontikis, Renée; Florent, Jean-Claude

    2009-10-15

    A convenient one-pot synthesis of 2-aroylindoles using a domino palladium-catalyzed C,N-coupling/carbonylation/C,C-coupling sequence is described. The reaction involved easily prepared 2-gem-dibromovinylanilines and boronic acids under carbon monoxide. Optimized reaction conditions allowed the construction of a wide variety of highly functionalized 2-aroyl-/heteroaroylindoles in satisfactory yields.

  4. Metal carbonyl vapor generation coupled with dielectric barrier discharge to avoid plasma quench for optical emission spectrometry.

    Science.gov (United States)

    Cai, Yi; Li, Shao-Hua; Dou, Shuai; Yu, Yong-Liang; Wang, Jian-Hua

    2015-01-20

    The scope of dielectric barrier discharge (DBD) microplasma as a radiation source for optical emission spectrometry (OES) is extended by nickel carbonyl vapor generation. We proved that metal carbonyl completely avoids the extinguishing of plasma, and it is much more suitable for matching the DBD excitation and OES detection with respect to significant DBD quenching by concomitant hydrogen when hydride generation is used. A concentric quartz UV reactor allows sample solution to flow through the central channel wherein to efficiently receive the uniformly distributed UV irradiation in the confined cylindrical space between the concentric tubes, which facilitates effective carbonyl generation in a nickel solution. The carbonyl is transferred into the DBD excitation chamber by an argon stream for nickel excitation, and the characteristic emission of nickel at 232.0 nm is detected by a charge-coupled device (CCD) spectrometer. A 1.0 mL sample solution results in a linear range of 5-100 μg L(-1) along with a detection limit of 1.3 μg L(-1) and a precision of 2.4% RSD at 50 μg L(-1). The present DBD-OES system is validated by nickel in certified reference materials.

  5. Iodine-catalyzed addition of 2-mercaptoethanol to chalcone derivatives: Synthesis of the novel β-mercapto carbonyl compounds

    Directory of Open Access Journals (Sweden)

    Gürkan Yerli

    2012-01-01

    Full Text Available In this study, a series of novel β-mercapto carbonyl derivatives (3-(2-hydroxyethylthio-1,3-diarylpropan-1-one (5a-i were prepared by addition of 2-mercaptoethanol (4 to chalcones (3a-i in the presence of catalytic amount of iodine (10 mol % in CH 2Cl 2.

  6. Ruthenium supported on magnetic nanoparticles: An efficient and recoverable catalyst for hydrogenation of alkynes and transfer hydrogenation of carbonyl compounds

    Science.gov (United States)

    Ruthenium supported on surface modified magnetic nanoparticles (NiFe2O4) has been successfully synthesized and applied for hydrogenation of alkynes at room temperature as well as transfer hydrogenation of a number of carbonyl compounds under microwave irradiation conditions. The ...

  7. The influence of chirality in the amide side chain on the carbonyl orientation in rotational isomers of 3-carbamoylpyridinium halides

    NARCIS (Netherlands)

    Bastiaansen, L.A.M.; Vermeulen, T.J.M.; Buck, H.M.; Smeets, W.J.J.; Kanters, J.A.

    1988-01-01

    The direction of the carbonyl orientation in solid amide rotamers of 3-(N-methyl-N-a-methylbenzylcarbamoyl)-1,2,4-trimethylpyridinium iodide is governed by the (R)- or (S)-chirality in the amide side chain; X-ray structures and c.d. spectra are correlated.

  8. Characteristics and personal exposures of carbonyl compounds in the subway stations and in-subway trains of Shanghai, China.

    Science.gov (United States)

    Feng, Yanli; Mu, Cuicui; Zhai, Jinqing; Li, Jian; Zou, Ting

    2010-11-15

    Carbonyl compounds including their concentrations, potential sources, diurnal variations and personal exposure were investigated in six subway stations and in-subway trains in Shanghai in June 2008. The carbonyls were collected onto solid sorbent (Tenax TA) coated with pentafluorophenyl hydrazine (PFPH), followed by solvent extraction and gas chromatography (GC)/mass spectrometry (MS) analysis of the PFPH derivatives. The total carbonyl concentrations of in-subway train were about 1.4-2.5 times lower than in-subway stations. A significant correlation (R>0.5, psubway stations. The diurnal variations in both the subway station and in-subway train showed that the concentrations of most carbonyls were much higher in the morning rush hour than in other sampling periods. Additionally, pronounced diurnal variations of acetaldehyde concentration before and after the evening peak hour in the subway train suggested that passengers contributed to high acetaldehyde levels. The personal exposure showed that the underground subway stations were important microenvironment for exposure to formaldehyde and acetaldehyde. Copyright © 2010 Elsevier B.V. All rights reserved.

  9. Ligand-Enabled γ-C–H Olefination and Carbonylation: Construction of β-Quaternary Carbon Centers

    Science.gov (United States)

    2015-01-01

    Monoselective γ-C–H olefination and carbonylation of aliphatic acids has been accomplished by using a combination of a quinoline-based ligand and a weakly coordinating amide directing group. The reaction provides a new route for constructing richly functionalized all-carbon quaternary carbon centers at the β-position of aliphatic acids. PMID:24666182

  10. Reactive carbonyl compounds impair wound healing by vimentin collapse and loss of the primary cilium.

    Science.gov (United States)

    Rodríguez-Ribera, Lara; Slattery, Craig; Mc Morrow, Tara; Marcos, Ricard; Pastor, Susana

    2017-10-01

    In renal pathologies tubulo-interstitial fibrosis results from an aberrant wound-healing ability where the normal epithelial tissue is substituted for scar tissue caused by accumulation of extracellular matrix proteins (ECM). During the wound-healing process, epithelial cells may undergo epithelial-mesenchymal transition (EMT) acquiring a mesenchymal-like phenotype that allows cells to migrate and re-epithelialize the wound site. It has been reported that chronic inflammation and uremic milieu are involved in wound-healing and enhanced kidney damage in chronic kidney disease (CKD) patients. In this study we evaluated reactive carbonyl compounds (RCC) effects on renal wound healing. The compounds resulting from carbonyl stress evaluated in this study were glyoxal (GO), methylglyoxal (MGO), malondialdehyde (MDA) and 4-hydroxy-hexenal (HHE). Wound repair ability was evaluated by the wound healing assay using HK-2 cells. EMT was evaluated by morphological, protein and transcriptional changes using microscopy, western blot, zymography and RT-qPCR. Changes in the vimentin network and primary cilia were assessed by immunofluorescence. Our data demonstrated that MDA and GO delay wound closure mediated by vimentin disruption, which caused collagen I mRNA decrease, and deciliation. In contrast, HHE treatment (and MGO to a minor degree) induced morphological changes and increased mesenchymal marker expression and gelatinase activity in HK-2 cells. In this study, we have demonstrated for the first time that exposure to RCC differentially affects wound healing in proximal tubular epithelia. A better comprehension of effects of uremic toxins on wound healing and fibrosis and migration is necessary to seek mechanisms to slow down renal fibrosis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Neurotoxicity of carbonyl sulfide in F344 rats following inhalation exposure for up to 12 weeks

    International Nuclear Information System (INIS)

    Morgan, Daniel L.; Little, Peter B.; Herr, David W.; Moser, Virginia C.; Collins, Bradley; Herbert, Ronald; Johnson, G. Allan; Maronpot, Robert R.; Harry, G. Jean; Sills, Robert C.

    2004-01-01

    Carbonyl sulfide (COS), a high-priority Clean Air Act chemical, was evaluated for neurotoxicity in short-term studies. F344 rats were exposed to 75-600 ppm COS 6 h per day, 5 days per week for up to 12 weeks. In rats exposed to 500 or 600 ppm for up to 4 days, malacia and microgliosis were detected in numerous neuroanatomical regions of the brain by conventional optical microscopy and magnetic resonance microscopy (MRM). After a 2-week exposure to 400 ppm, rats were evaluated using a functional observational battery. Slight gait abnormality was detected in 50% of the rats and hypotonia was present in all rats exposed to COS. Decreases in motor activity, and forelimb and hindlimb grip strength were also detected. In rats exposed to 400 ppm for 12 weeks, predominant lesions were in the parietal cortex area 1 (necrosis) and posterior colliculus (neuronal loss, microgliosis, hemorrhage), and occasional necrosis was present in the putamen, thalamus, and anterior olivary nucleus. Carbonyl sulfide specifically targeted the auditory system including the olivary nucleus, nucleus of the lateral lemniscus, and posterior colliculus. Consistent with these findings were alterations in the amplitude of the brainstem auditory evoked responses (BAER) for peaks N 3 , P 4 , N 4 , and N 5 that represented changes in auditory transmission between the anterior olivary nucleus to the medial geniculate nucleus in animals after exposure for 2 weeks to 400 ppm COS. A concentration-related decrease in cytochrome oxidase activity was detected in the posterior colliculus and parietal cortex of exposed rats as early as 3 weeks. Cytochrome oxidase activity was significantly decreased at COS concentrations that did not cause detectable lesions, suggesting that disruption of the mitochondrial respiratory chain may precede these brain lesions. Our studies demonstrate that this environmental air contaminant has the potential to cause a wide spectrum of brain lesions that are dependent on the degree

  12. Chitosan Prevents Gentamicin-Induced Nephrotoxicity via a Carbonyl Stress-Dependent Pathway

    Directory of Open Access Journals (Sweden)

    Chu-Kung Chou

    2015-01-01

    Full Text Available Aminoglycosides are widely used to treat infections; however, their applications are limited by nephrotoxicity. With the increase of antibiotic resistance, the use of aminoglycosides is inevitable. Low-molecular-weight chitosan (LMWC has shown renal protective effects in dialysis patients. However, no study has evaluated LMWC for preventing aminoglycoside-induced nephrotoxicity or determined the mechanisms underlying the renal protective effects. In this study, LMWC (165 or 825 mg/kg/day or metformin (100 mg/kg/day was orally administered for 13 days to rats with nephropathy induced by gentamicin (GM, a kind of aminoglycoside (150 mg/kg/day i.p. for 6 days. Both LMCW doses improved renal function. Serum creatinine levels improved in rats treated with 165 and 825 mg/kg/day LMWC (from 2.14 ± 0.74 mg/dL to 1.26 ± 0.46 mg/dL and 0.69 ± 0.12 mg/dL, resp., P < 0.05. Blood urea nitrogen levels were also improved in these rats (from 73.73 ± 21.13 mg/dL to 58.70 ± 22.71 mg/dL and 28.82 ± 3.84 mg/dL, resp., P < 0.05. Additionally, renal tissue morphology improved after LMWC treatment, and accumulation of renal methylglyoxal, a damage factor associated with carbonyl stress, was reversed. These results show that LMWC prevents GM-induced renal toxicity via a carbonyl stress-dependent pathway.

  13. Synthesis and preclinical evaluation of [11C-carbonyl]PF-04457845 for neuroimaging of fatty acid amide hydrolase

    International Nuclear Information System (INIS)

    Hicks, Justin W.; Parkes, Jun; Sadovski, Oleg; Tong, Junchao; Houle, Sylvain; Vasdev, Neil; Wilson, Alan A.

    2013-01-01

    Introduction: Fatty acid amide hydrolase (FAAH) has a significant role in regulating endocannabinoid signaling in the central nervous system. As such, FAAH inhibitors are being actively sought for pain, addiction, and other indications. This has led to the recent pursuit of positron emission tomography (PET) radiotracers targeting FAAH. We report herein the preparation and preclinical evaluation of [ 11 C-carbonyl]PF-04457845, an isotopologue of the potent irreversible FAAH inhibitor. Methods: PF-04457845 was radiolabeled at the carbonyl position via automated [ 11 C]CO 2 -fixation. Ex vivo brain biodistribution of [ 11 C-carbonyl]PF-04457845 was carried out in conscious rats. Specificity was determined by pre-administration of PF-04457845 or URB597 prior to [ 11 C-carbonyl]PF-04457845. In a separate experiment, rats injected with the title radiotracer had whole brains excised, homogenized and extracted to examine irreversible binding to brain parenchyma. Results: The title compound was prepared in 5 ± 1% (n = 4) isolated radiochemical yield based on starting [ 11 C]CO 2 (decay uncorrected) within 25 min from end-of-bombardment in > 98% radiochemical purity and a specific activity of 73.5 ± 8.2 GBq/μmol at end-of-synthesis. Uptake of [ 11 C-carbonyl]PF-04457845 into the rat brain was high (range of 1.2–4.4 SUV), heterogeneous, and in accordance with reported FAAH distribution. Saturable binding was demonstrated by a dose-dependent reduction in brain radioactivity uptake following pre-treatment with PF-04457845. Pre-treatment with the prototypical FAAH inhibitor, URB597, reduced the brain radiotracer uptake in all regions by 71–81%, demonstrating specificity for FAAH. The binding of [ 11 C-carbonyl]PF-04457845 to FAAH at 40 min post injection was irreversible as 98% of the radioactivity in the brain could not be extracted. Conclusions: [ 11 C-carbonyl]PF-04457845 was rapidly synthesized via an automated radiosynthesis. Ex vivo biodistribution studies in

  14. Electrochemical Behaviour, IR Spectroelectrochemistry and Theoretical Studies of Tetracobalt Carbonyl Cluster Complexes with a Facial Cyclooctatetraene Ligand

    Czech Academy of Sciences Publication Activity Database

    Fiedler, Jan; Nervi, C.; Osella, D.; Calhorda, M. J.; Godinho, S. M. C.; Merkel, R.; Wadepohl, H.

    - (2002), s. 3705-3711 ISSN 1472-7773 R&D Projects: GA MŠk OC D15.10 Institutional research plan: CEZ:AV0Z4040901 Keywords : spectroelectrochemistry * electron-transfer reactions Subject RIV: CG - Electrochemistry Impact factor: 3.023, year: 2002

  15. Carbonyl compound emissions from a heavy-duty diesel engine fueled with diesel fuel and ethanol-diesel blend.

    Science.gov (United States)

    Song, Chonglin; Zhao, Zhuang; Lv, Gang; Song, Jinou; Liu, Lidong; Zhao, Ruifen

    2010-05-01

    This paper presents an investigation of the carbonyl emissions from a direct injection heavy-duty diesel engine fueled with pure diesel fuel (DF) and blended fuel containing 15% by volume of ethanol (E/DF). The tests have been conducted under steady-state operating conditions at 1200, 1800, 2600 rpm and idle speed. The experimental results show that acetaldehyde is the most predominant carbonyl, followed by formaldehyde, acrolein, acetone, propionaldehyde and crotonaldehyde, produced from both fuels. The emission factors of total carbonyls vary in the range 13.8-295.9 mg(kWh)(-1) for DF and 17.8-380.2mg(kWh)(-1) for E/DF, respectively. The introduction of ethanol into diesel fuel results in a decrease in acrolein emissions, while the other carbonyls show general increases: at low engine speed (1200 rpm), 0-55% for formaldehyde, 4-44% for acetaldehyde, 38-224% for acetone, and 5-52% for crotonaldehyde; at medium engine speed (1800 rpm), 106-413% for formaldehyde, 4-143% for acetaldehyde, 74-113% for acetone, 114-1216% for propionaldehyde, and 15-163% for crotonaldehyde; at high engine speed (2600 rpm), 36-431% for formaldehyde, 18-61% for acetaldehyde, 22-241% for acetone, and 6-61% for propionaldehyde. A gradual reduction in the brake specific emissions of each carbonyl compound from both fuels is observed with increase in engine load. Among three levels of engine speed employed, both DF and E/DF emit most CBC emissions at high engine speed. On the whole, the presence of ethanol in diesel fuel leads to an increase in aldehyde emissions. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  16. Preparation of Different Substitued Polypyridine Ligands, Ruthenium(II)-Bridged Complexes and Spectoscopıc Studies.

    Science.gov (United States)

    Obali, Aslihan Yilmaz; Ucan, Halil Ismet

    2016-09-01

    Novel different substitued polypyridine ligands 4-((4-(1H-imidazo[4,5-f][1,10]phenanthroline-2-yl)phenoxy)methyl)benzaldehyde (BA-PPY), (E)-N-(4-((4-(1H-imidazo[4,5-f][1,10]phenanthroline-2-yl)phenoxy)methyl)benzylidene)-pyrene-4-amine (PR-PPY), (E)-N-(4-((4-(1H-imidazo[4,5-f][1,10] phenanthroline-2-yl)phenoxy)methyl)benzylidene)-1,10-phenanthroline-5amine (FN-PPY), 2-(4-(bromomethyl)phenyl)-1H-imidazo[4,5-f][1,10] phenanthroline (BR-PPY), 2-(4-(azidomethyl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline (N3-PPY) and triazole containing polypyridine ligand 3,4-bis[(4-(metoxy)-1,2,3-triazole)1-methylphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline)] benzaldehyde (BA-DIPPY) and Ruthenium(II) complexes were synthesized and characterized. Their photopysical properties were investigated. The complexes RuP(PR-PPY), RuB(PR-PPY, RuP(FN-PPY) and RuB(FN-PPY) exhibited a broad absorption bands at 485, 475, 476, and 453 nm, respectively, assignable to the spin-allowed MLCT (dπ-π*) transition. The emission maxima of the pyrene-appended polypyridine ligand PR-PPY was observed at λems = 616 nm and the phenanthroline-appended polypyridine ligand FN-PPY was observed at λems = 668 nm. And the emission maxima of the complexes RuP(PR-PPY), RuB(PR-PPY), RuP(FN-PPY) and RuB(FN-PPY) were observed at λems = 646, 646, 685 and 685 nm, respectively. As seen in fluorescence spectra, the fluorescence intensities of the ligands are higher than their metal complexes. This is because of quenching effect of Ruthenium(II) metal on chromophore groups.

  17. Organometallic rhodium(III) and iridium(III) cyclopentadienyl complexes with curcumin and bisdemethoxycurcumin co-ligands.

    Science.gov (United States)

    Pettinari, Riccardo; Marchetti, Fabio; Pettinari, Claudio; Condello, Francesca; Petrini, Agnese; Scopelliti, Rosario; Riedel, Tina; Dyson, Paul J

    2015-12-21

    A series of half-sandwich cyclopentadienyl rhodium(III) and iridium(III) complexes of the type [Cp*M(curc/bdcurc)Cl] and [Cp*M(curc/bdcurc)(PTA)][SO3CF3], in which Cp* = pentamethylcyclopentadienyl, curcH = curcumin and bdcurcH = bisdemethoxycurcumin as O^O-chelating ligands, and PTA = 1,3,5-triaza-7-phosphaadamantane, is described. The X-ray crystal structures of three of the complexes, i.e. [Cp*Rh(curc)(PTA)][SO3CF3] (5), [Cp*Rh(bdcurc)(PTA)][SO3CF3] (6) and [Cp*Ir(bdcurc)(PTA)][SO3CF3] (8), confirm the expected "piano-stool" geometry. With the exception of 5, the complexes are stable under pseudo-physiological conditions and are moderately cytotoxic to human ovarian carcinoma (A2780 and A2780cisR) cells and also to non-tumorigenic human embryonic kidney (HEK293) cells, but lack the cancer cell selectivity observed for related arene ruthenium(II) complexes.

  18. Asymmetric oxidation of vinyl- and ethynyl terthiophene ligands in triruthenium complexes.

    Science.gov (United States)

    Zhang, Jing; Sun, Chao-Fang; Zhang, Ming-Xing; Hartl, František; Yin, Jun; Yu, Guang-Ao; Rao, Li; Liu, Sheng Hua

    2016-01-14

    A series of ruthenium(ii) complexes [{RuCl(CO)(PMe3)3(-CH[double bond, length as m-dash]CH-)}nX], (: n = 3, X = 3,3''-dimethyl-2,2':3',2''-terthiophene; : n = 2, X = 2,2'-bithiophene; : n = 2, X = 2,3-bis(3-methylthiophen-2-yl)benzothiophene) and [{Cp*(dppe)2Ru(-C[triple bond, length as m-dash]C-)}3X], (X = 3,3''-dimethyl-2,2':3',2''-terthiophene), were prepared and characterized by (1)H, (13)C and (31)P NMR. Their redox, spectroscopic and bonding properties were studied with a range of spectro-electrochemical methods in combination with density functional theory calculations. The first two anodic steps observed for and are largely localized on the lateral frameworks of the molecular triangle, the direct conjugation between them being precluded due to the photostable open form of the dithienyl ethene moiety. The third anodic step is then mainly localized on the centerpiece of the triangular structure, affecting both bithiophene laterals. The experimental IR and UV-vis-NIR spectroelectrochemical data and, largely, also DFT calculations account for this explanation, being further supported by direct comparison with the anodic behavior of reference diruthenium complexes and .

  19. Conductometric and voltammetric studies on the bis(triphenyl phosphine) ruthenium(II) complex, cis-[RuCl2(L)(PPh3)2], where L: 2-(2'-pyridyl)quinoxaline

    Czech Academy of Sciences Publication Activity Database

    Tsierkezos, Nikos; Philippopoulos, A. I.

    2009-01-01

    Roč. 362, č. 4 (2009), s. 3079-3087 ISSN 0020-1693 Grant - others:Kapodistrias Program(GR) 70/4/9277 Institutional research plan: CEZ:AV0Z40550506 Keywords : assocition constant * conductivity * cyclic voltammetry * ruthenium * quinoxaline Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.322, year: 2009

  20. Synthesis, Photophysical and Electrochemical Properties of a Mixed Bipyridyl-Phenanthrolyl Ligand Ru(II Heteroleptic Complex Having trans-2-Methyl-2-butenoic Acid Functionalities

    Directory of Open Access Journals (Sweden)

    Adewale O. Adeloye

    2011-09-01

    Full Text Available In this work, two ligands: 4-(trans-2-Methyl-2-butenoic acid-2,2'-bipyridine (L1 and 5-(trans-2-methyl-2-butenoic acid-1,10-phenanthroline (L2, with the corresponding mixed-ligand heteroleptic Ru(II complex were synthesized and characterized by FT-IR, 1H-, 13C-NMR spectroscopy and elemental analysis. The influence of the mixed functionalized polypyridyl ruthenium(II complex on the photophysical and electrochemical properties were investigated and compared to individual single-ligand homoleptic complexes. Interestingly, the mixed-ligand complex formulated as [RuL1L2(NCS2] exhibits broad and intense metal-to-ligand charge transfer (MLCT absorption with a high molar extinction coefficient (λmax = 514 nm, ε = 69,700 M−1 cm−1, better than those of individual single-ligand complexes, [Ru(L12(NCS2] and [Ru(L22(NCS2], and a strong photoluminescence intensity ratio in the red region at λem = 686 nm. The electrochemical properties of the complex indicated that the redox processes are ligand-based.

  1. Anion-selective interaction and colorimeter by an optical metalloreceptor based on ruthenium(II) 2,2'-biimidazole: hydrogen bonding and proton transfer.

    Science.gov (United States)

    Cui, Ying; Mo, Hao-Jun; Chen, Jin-Can; Niu, Yan-Li; Zhong, Yong-Rui; Zheng, Kang-Cheng; Ye, Bao-Hui

    2007-08-06

    A new anion sensor [Ru(bpy)2(H2biim)](PF6)2 (1) (bpy = 2,2'-bipyridine and H2biim = 2,2'-biimidazole) has been developed, in which the Ru(II)-bpy moiety acts as a chromophore and the H2biim ligand as an anion receptor via hydrogen bonding. A systematic investigation shows that 1 is an eligible sensor for various anions. It donates protons for hydrogen bonding to Cl-, Br-, I-, NO3-, HSO4-, H2PO4-, and OAc- anions and further actualizes monoproton transfer to the OAc- anion, changing color from yellow to orange brown. The fluoride ion has a high affinity toward the N-H group of the H2biim ligand for proton transfer, rather than hydrogen bonding, because of the formation of the highly stable HF2- anion, resulting in stepwise deprotonation of the two N-H fragments. These processes are signaled by vivid color changes from yellow to orange brown and then to violet because of second-sphere donor-acceptor interactions between Ru(II)-H2biim and the anions. The significant color changes can be distinguished visually. The processes are not only determined by the basicity of anion but also by the strength of hydrogen bonding and the stability of the anion-receptor complexes. The design strategy and remarkable photophysical properties of sensor 1 help to extend the development of anion sensors.

  2. Functional mechanism of C-terminal tail in the enzymatic role of porcine testicular carbonyl reductase: a combined experiment and molecular dynamics simulation study of the C-terminal tail in the enzymatic role of PTCR.

    Directory of Open Access Journals (Sweden)

    Minky Son

    Full Text Available Porcine testicular carbonyl reductase, PTCR which is one of the short chain dehydrogenases/reductases (SDR superfamily catalyzes the NADPH-dependent reduction of carbonyl compounds including steroids and prostaglandins. Previously we reported C-terminal tail of PTCR was deleted due to a nonsynonymous single nucleotide variation (nsSNV. Here we identified from kinetic studies that the enzymatic properties for 5α-dihydrotestosterone (5α-DHT were different between wild-type and C-terminal-deleted PTCRs. Compared to wild-type PTCR, C-terminal-deleted PTCR has much higher reduction rate. To investigate structural difference between wild-type and C-terminal-deleted PTCRs upon 5α-DHT binding, we performed molecular dynamics simulations for two complexes. Using trajectories, molecular interactions including hydrogen bonding patterns, distance between 5α-DHT and catalytic Tyr193, and interaction energies are analyzed and compared. During the MD simulation time, the dynamic behavior of C-terminal tail in wild-type PTCR is also examined using essential dynamics analysis. The results of our simulations reveal that the binding conformation of 5α-DHT in C-terminal-deleted PTCR is more favorable for reduction reaction in PTCR, which shows strong agreement with kinetic data. These structural findings provide valuable information to understand substrate specificity of PTCR and further kinetic properties of enzymes belonging to the SDR superfamily.

  3. Analysis of carbonyl compounds via headspace solid-phase microextraction with on-fiber derivatization and gas chromatographic-ion trap tandem mass spectrometric determination of their O-(2,3,4,5,6-pentafluorobenzyl)oxime derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Schmarr, Hans-Georg [Dienstleistungszentrum Laendlicher Raum (DLR) Rheinpfalz, Breitenweg 71, D-67435 Neustadt an der Weinstrasse (Germany)], E-mail: hans-georg.schmarr@dlr.rlp.de; Potouridis, Theodoros; Ganss, Sebastian; Sang, Wei; Koepp, Benedikt; Bokuz, Ursula; Fischer, Ulrich [Dienstleistungszentrum Laendlicher Raum (DLR) Rheinpfalz, Breitenweg 71, D-67435 Neustadt an der Weinstrasse (Germany)

    2008-06-09

    An improved method for the analysis of carbonyls is described utilizing a headspace solid-phase microextraction (HS-SPME) step and on-fiber derivatization with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBHA) hydrochloride. Thermal desorption of the oxime derivatives formed on the fiber is followed by gas chromatographic separation coupled to an ion trap tandem mass spectrometer (GC-ITMS). Selecting specific fragment ions within the electron ionization (EI{sup +}) mass spectra of these oxime derivatives as precursor ions for MS-MS fragmentation provides a suitable method for the target analysis of individual carbonyl classes, such as alkanals, (E)-2-alkenals, (E,E)-2,4-alkadienals, and others. Retention indices on polar as well as on apolar stationary phases along with EI{sup +} mass spectra patterns are presented for a large set of oxime derivatives, giving valuable information needed for unambiguous assignment of substances in complex sample matrices. The fast sample preparation and derivatization step via HS-SPME can be automated and is applicable to a variety of biological samples and foodstuffs, allowing rapid and sensitive screening analyses of important aldehydic biomarkers and aroma active compounds.

  4. Redox and catalytic properties of new polypyrrole modified electrodes functionalized by [Ru(bpea)(bpy)H{sub 2}O]{sup 2+} complexes; bpea=N,N'-bis(2-pyridylmethyl)ethylamine, bpy=2,2'-bipyridine

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Montserrat; Romero, Isabel; Sens, Cristina; Llobet, Antoni; Deronzier, Alain

    2003-04-05

    New ruthenium(II) complexes containing one or two pyrrole-functionalized polypyridylic ligands have been prepared in order to study their electrochemical behaviour in heterogeneous phase, after anodic polymerization from CH{sub 2}Cl{sub 2} solution on an electrode surface. Complexes containing one pyrrole unit have general formula [Ru(bpea-pyr)(bpy)(L)]{sup 2+} (bpea-pyr=N-[3-bis(2-pyridylmethyl)aminopropyl]pyrrole, bpy=2,2'-bipyridine, L=Cl, complex 3, or L=H{sub 2}O, complex 1), whereas compounds having two pyrrole units correspond to [Ru(bpea-pyr)(bpy-pyr)(L)]{sup 2+} (bpy-pyr=4-methyl-4'-pyrrolylbutyl-2,2'-bipyridine, L=Cl, complex 4, or L=H{sub 2}O, complex 2). Upon oxidative polymerization, all complexes form highly stable polypyrrolic films on a graphite disk electrode surface. An electrode modified with complex 2 polypyrrole coating film, C/poly-2, has been tested as heterogeneous catalyst for the oxidation of benzyl alcohol, showing a remarkably high efficiency and notably improving the results obtained with analogous complexes in homogeneous phase.

  5. Recent Developments in Carbonylation Chemistry Using [13 C]CO, [11 C]CO and [14 C]CO.

    Science.gov (United States)

    Nielsen, Dennis U; Neumann, Karoline T; Lindhardt, Anders T; Skrydstrup, Troels

    2018-06-01

    Carbon monoxide represents the most important C1-building block for the chemical industry, both for the production of bulk and fine chemicals, but also for synthetic fuels. Yet, its toxicity and subsequently its cautious handling has limited its applications in medicinal chemistry research and in particular for the synthesis of pharmaceutically relevant molecules. Recent years have nevertheless witnessed a considerable headway on the development of carbon monoxide surrogates and reactor systems, which provide an ideal setting for performing carbonylation chemistry with stoichiometric and sub-stoichiometric carbon monoxide. Such set-ups are particularly ideal for the introduction of isotope labels such as carbon-11, carbon-13 and carbon-14 into bioactive compounds. This review summarizes this growing field and examines the large number of carbonylation reactions that can be exploited for the introduction of a carbon isotope. This article is protected by copyright. All rights reserved.

  6. Magnetically tunable elasticity for magnetic hydrogels consisting of carrageenan and carbonyl iron particles.

    Science.gov (United States)

    Mitsumata, Tetsu; Honda, Atomu; Kanazawa, Hiroki; Kawai, Mika

    2012-10-11

    A new class of magnetoelastic gel that demonstrates drastic and reversible changes in storage modulus without using strong magnetic fields was obtained. The magnetic gel consists of carrageenan and carbonyl iron particles. The magnetic gel with a volume fraction of magnetic particles of 0.30 exhibited a reversible increase by a factor of 1400 of the storage modulus upon a magnetic field of 500 mT, which is the highest value in the past for magnetorheological soft materials. It is considered that the giant magnetoelastic behavior is caused by both high dispersibility and high mobility of magnetic particles in the carrageenan gel. The off-field storage modulus of the magnetic gel at volume fractions below 0.30 obeyed the Krieger-Dougherty equation, indicating random dispersion of magnetic particles. At 500 mT, the storage modulus was higher than 4.0 MPa, which is equal to that of magnetic fluids, indicating that the magnetic particles move and form a chain structure by magnetic fields. Morphological study revealed the evidence that the magnetic particles embedded in the gel were aligned in the direction of magnetic fields, accompanied by stretching of the gel network. We conclude that the giant magnetoelastic phenomenon originates from the chain structure consisting of magnetic particles similar to magnetic fluids.

  7. Isotope effect in the carbonyl sulfide reaction with O(3P)

    DEFF Research Database (Denmark)

    Hattori, Shohei; Schmidt, Johan Albrecht; Mahler, Denise W.

    2012-01-01

    The sulfur kinetic isotope effect (KIE) in the reaction of carbonyl sulfide (OCS) with O((3)P) was studied in relative rate experiments at 298 ± 2 K and 955 ± 10 mbar. The reaction was carried out in a photochemical reactor using long path FTIR detection, and data were analyzed using a nonlinear...... least-squares spectral fitting procedure with line parameters from the HITRAN database. The ratio of the rate of the reaction of OC(34)S relative to OC(32)S was found to be 0.9783 ± 0.0062 ((34)e = (-21.7 ± 6.2)‰). The KIE was also calculated using quantum chemistry and classical transition state theory......; at 300 K, the isotopic fractionation was found to be (34)e = -14.8‰. The OCS sink reaction with O((3)P) cannot explain the large fractionation in (34)S, over +73‰, indicated by remote sensing data. In addition, (34)e in OCS photolysis and OH oxidation are not larger than 10‰, indicating that...

  8. The influence of oscillations on product selectivity during the palladium-catalysed phenylacetylene oxidative carbonylation reaction.

    Science.gov (United States)

    Novakovic, Katarina; Grosjean, Christophe; Scott, Stephen K; Whiting, Andrew; Willis, Mark J; Wright, Allen R

    2008-02-07

    This paper reports on the influence of oscillations on product selectivity as well as the dynamics of product formation during the palladium-catalysed phenylacetylene oxidative carbonylation reaction in a catalytic system (PdI2, KI, Air, NaOAc in methanol). The occurrence of the pH oscillations is related to PdI2 granularity and the initial pH drop after phenylacetylene addition. To achieve pH and reaction exotherm oscillations regulation of the amount of PdI2 is required, ensuring that the initial pH does not fall significantly below 1 after phenylacetylene addition. Experiments in both oscillatory and non-oscillatory pH regimes were performed in an HEL SIMULAR reaction calorimeter with the concentration-time profiles measured using a GC-MS. It is demonstrated that when operating in an oscillatory pH regime product formation may be suppressed until oscillations occur after which there is a steep increase in the formation of Z-2-phenyl-but-2-enedioic acid dimethyl ester. When operating in non-oscillatory pH mode the products are formed steadily over time with the main products being Z-2-phenyl-but-2-enedioic acid dimethyl ester, 2-phenyl-acrylic acid methyl ester and E-3-phenyl-acrylic acid methyl ester.

  9. Carbonylation of aryl bromides with palladium polyphthalocyanine/active carbon catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Ohkatsu, Y.; Nakazawa, K.; Osa, T.

    1979-11-01

    The reaction of bromobenzene with carbon monoxide over carbon-supported 1.7Vertical Bar3< palladium polyphthalocyanine yielded carbonylated products in the presence of water or methanol and only benzene and dibromobenzene in their absence. At 300/sup 0/C and 1 sec contact time, e.g., the reaction of a 1:2.6:1 mole ratio feed of bromobenzene/methanol/carbon monoxide yielded benzoic acid with 61.7Vertical Bar3< selectivity at 83.2Vertical Bar3< conversion, a 1:0.8:3 feed gave benzoic acid with 84.4Vertical Bar3< selectivity at 40.7Vertical Bar3< conversion. The addition of water instead of methanol gave higher conversions, e.g., a feed of 1:3:1 bromobenzene/water/carbon monoxide yielded benzoic acid with 69.2Vertical Bar3< selectivity at 90.9Vertical Bar3< conversion. Analyses of product distributions obtained in these and autoclaved experiments at 10-50 kg/sq cm carbon monoxide pressure suggested a free radical mechanism.

  10. Comparison of extraction techniques and mass spectrometric ionization modes in the analysis of wine volatile carbonyls

    Energy Technology Data Exchange (ETDEWEB)

    Zapata, Julian; Mateo-Vivaracho, Laura; Cacho, Juan [Laboratory for Flavor Analysis and Enology, Institute of Engineering of Aragon, I3A, Department of Analytical Chemistry, Faculty of Sciences, University of Zaragoza, 50009 Zaragoza (Spain); Ferreira, Vicente, E-mail: vferre@unizar.es [Laboratory for Flavor Analysis and Enology, Institute of Engineering of Aragon, I3A, Department of Analytical Chemistry, Faculty of Sciences, University of Zaragoza, 50009 Zaragoza (Spain)

    2010-02-15

    This work presents a comparative study of the analytical characteristics of two methods for the analysis of carbonyl compounds in wine, both based on the derivatization with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA). In the first method derivatives are formed in the solid phase extraction (SPE) cartridge in which the analytes have been previously isolated, while in the second method derivatives are formed in a solid phase microextraction (SPME) fibre saturated with vapors of the reagent and exposed to the sample headspace. In both cases detection has been carried out by electron impact (EI) or negative chemical ionization (NCI) mass spectrometry. The possibility of determining haloanisols simultaneously has been also considered. The method based on SPE presents, in general, better analytical properties than the SPME one. Although linearity was satisfactory for both methods (R{sup 2} > 0.99), repeatability of the SPE method (RSD < 10%) was better than that obtained with SPME (9% < RSD < 20%). Detection limits obtained with EI are better for the SPE method except for trihaloanisols, while with NCI detection limits for both strategies are comparable, although the SPME strategy presents worse results for ketones and methional. Detection limits are always lower with NCI, being the improvement most notable for SPME. Recovery experiments show that in the case of SPE, uncertainties are lower than 12% in all cases, while with the SPME method the imprecision plus the existence of matrix effects make the global uncertainty to be higher than 15%.

  11. Ester carbonyl vibration as a sensitive probe of protein local electric field.

    Science.gov (United States)

    Pazos, Ileana M; Ghosh, Ayanjeet; Tucker, Matthew J; Gai, Feng

    2014-06-10

    The ability to quantify the local electrostatic environment of proteins and protein/peptide assemblies is key to gaining a microscopic understanding of many biological interactions and processes. Herein, we show that the ester carbonyl stretching vibration of two non-natural amino acids, L-aspartic acid 4-methyl ester and L-glutamic acid 5-methyl ester, is a convenient and sensitive probe in this regard, since its frequency correlates linearly with the local electrostatic field for both hydrogen-bonding and non-hydrogen-bonding environments. We expect that the resultant frequency-electric-field map will find use in various applications. Furthermore, we show that, when situated in a non-hydrogen-bonding environment, this probe can also be used to measure the local dielectric constant (ε). For example, its application to amyloid fibrils formed by Aβ(16-22) revealed that the interior of such β-sheet assemblies has an ε value of approximately 5.6. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Improvement of operational stability of Ogataea minuta carbonyl reductase for chiral alcohol production.

    Science.gov (United States)

    Honda, Kohsuke; Inoue, Mizuha; Ono, Tomohiro; Okano, Kenji; Dekishima, Yasumasa; Kawabata, Hiroshi

    2017-06-01

    Directed evolution of enantio-selective carbonyl reductase from Ogataea minuta was conducted to improve the operational stability of the enzyme. A mutant library was constructed by an error-prone PCR and screened using a newly developed colorimetric assay. The stability of a mutant with two amino acid substitutions was significantly higher than that of the wild type at 50°C in the presence of dimethyl sulfoxide. Site-directed mutagenesis analysis showed that the improved stability of the enzyme can be attributed to the amino acid substitution of V166A. The half-lives of the V166A mutant were 11- and 6.1-times longer than those of the wild type at 50°C in the presence and absence, respectively, of 20% (v/v) dimethyl sulfoxide. No significant differences in the substrate specificity and enantio-selectivity of the enzyme were observed. The mutant enzyme converted 60 mM 2,2,2-trifluoroacetophenone to (R)-(-)-α-(trifluoromethyl)benzyl alcohol in a molar yield of 71% whereas the conversion yield with an equivalent concentration of the wild-type enzyme was 27%. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  13. Synthesis, characterization and magnetorheological properties of carbonyl iron suspension with superparamagnetic nanoparticles as an additive

    International Nuclear Information System (INIS)

    Leong, Siti Asma’ Nikmat; Mohd Samin, Pakharuddin; Idris, Ani; Rahman, Azura Hanis A; Mazlan, Saiful Amri

    2016-01-01

    Magnetorheological (MR) fluids are suspensions of micron-sized particles dispersed in carrier fluid. Due to high density magnetic particles, MR fluids are facing the problem with the instability of the suspension caused by high settling rate. Recently, researches have been conducted on the advantages of using the mixture of magnetic nanoparticles and microparticles, called bidisperse MR fluids. However, even though the sedimentation stability is improved, there is a reduction in dynamic yield stress when the nanoparticle is introduced. In this work, the investigation of magnetic iron nanoparticles (γ-Fe 2 O 3 ) as an additive to magnetic carbonyl iron (CI) suspension has been proposed so as to improve the sedimentation stability and redispersibility, but at the same time enhance the MR performance. The results indicated that the addition of nanoparticles reduced the sedimentation rate, improved redispersibility and enhanced the rheological performance of MR fluids as the particle fill the voids between the microparticles and strengthened the interparticle chains contributing to well-arranged particle structures. (paper)

  14. Comparison of extraction techniques and mass spectrometric ionization modes in the analysis of wine volatile carbonyls

    International Nuclear Information System (INIS)

    Zapata, Julian; Mateo-Vivaracho, Laura; Cacho, Juan; Ferreira, Vicente

    2010-01-01

    This work presents a comparative study of the analytical characteristics of two methods for the analysis of carbonyl compounds in wine, both based on the derivatization with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA). In the first method derivatives are formed in the solid phase extraction (SPE) cartridge in which the analytes have been previously isolated, while in the second method derivatives are formed in a solid phase microextraction (SPME) fibre saturated with vapors of the reagent and exposed to the sample headspace. In both cases detection has been carried out by electron impact (EI) or negative chemical ionization (NCI) mass spectrometry. The possibility of determining haloanisols simultaneously has been also considered. The method based on SPE presents, in general, better analytical properties than the SPME one. Although linearity was satisfactory for both methods (R 2 > 0.99), repeatability of the SPE method (RSD < 10%) was better than that obtained with SPME (9% < RSD < 20%). Detection limits obtained with EI are better for the SPE method except for trihaloanisols, while with NCI detection limits for both strategies are comparable, although the SPME strategy presents worse results for ketones and methional. Detection limits are always lower with NCI, being the improvement most notable for SPME. Recovery experiments show that in the case of SPE, uncertainties are lower than 12% in all cases, while with the SPME method the imprecision plus the existence of matrix effects make the global uncertainty to be higher than 15%.

  15. An oxidoreductase from 'Alphonso' mango catalyzing biosynthesis of furaneol and reduction of reactive carbonyls.

    Science.gov (United States)

    Kulkarni, Ram; Chidley, Hemangi; Deshpande, Ashish; Schmidt, Axel; Pujari, Keshav; Giri, Ashok; Gershenzon, Jonathan; Gupta, Vidya

    2013-01-01

    Two furanones, furaneol (4-hydroxy-2,5-dimethyl-3(2H)-furanone) and mesifuran (2,5-dimethyl-4-methoxy-3(2H)-furanone), are important constituents of flavor of the Alphonso cultivar of mango (Mangifera indica). To get insights into the biosynthesis of these furanones, we isolated an enone oxidoreductase gene from the Alphonso mango. It has high sequence similarity to an alkenal/one oxidoreductase from cucumber (79% identity) and enone oxidoreductases from tomato (73% identity) and strawberry (72% identity). The complete open reading frame was expressed in E. coli and the (his)6-tagged recombinant protein was purified by affinity chromatography. The purified protein assayed with NADH as a reducing agent converted D-fructose-1,6-diphosphate into furaneol, the immediate precursor of mesifuran. The enzyme was also able to convert two highly reactive carbonyls, 3-buten-2-one and 1-penten-3-one, produced by lipid peroxidation in plants, into their saturated derivatives. Expression profiling in various ripening stages of Alphonso fruits depicted an expression maxima at 10 days after harvest stage, shortly before the appearance of the maximum amount of furanones (completely ripe stage, 15 days after harvest). Although no furanones were detected at the 0 day after harvest stage, significant expression of this gene was detected in the fruits at this stage. Overall, the results suggest that this oxidoreductase plays important roles in Alphonso mango fruits.

  16. Role of the oceans in the atmospheric cycle of carbonyl sulfide

    International Nuclear Information System (INIS)

    Johnson, J.E.

    1985-01-01

    Carbonyl sulfide (OCS) is both the dominant sulfur gas in the remote troposphere and, along with volcanoes, a major source of sulfur for the stratospheric sulfate layer. Prior to this work the ocean was regarded as a major sink for atmospheric OCS. The purpose of this study has been to assess the magnitude of the global air-sea flux of OCS. The author designed an analytical system which was centered around a Varian-3700 gas chromatograph with a flame-photometric detector. To increase the sensitivity of the detector, the hydrogen gas for the flame was doped with sulfur hexafluoride. Air samples were concentrated in a liquid nitrogen cooled freeze-out loop, then injected into the gas chromatograph. Water samples purged with sulfur-free zero-air which was analyzed similarly. He also built a permeation tube system for chemical standardization. This equipment was taken on two oceanographic cruises on the Pacific Ocean, one in the spring of 1983 and a second in the spring of 1983. Both of these cruises included measurements of air and seawater concentrations of OCS from the equator to the Aleutian Islands. The Henry's law constant of solubility for OCS was measured in the laboratory for filtered and boiled seawater at three temperatures

  17. Reaction of phosphorus ylides with carbonyl compounds in supercritical carbon dioxide

    International Nuclear Information System (INIS)

    Jeong, Kyung Il; Kim, Hak Do; Shim, Jae Jin; Ra, Choon Sup

    2004-01-01

    The condensation reaction of (benzylene)triphenylphosphoranes with carbonyl compounds in supercritical carbon dioxide was examined. Reactions of (benzylene)phosphoranes (ca. 1 mmol) with several benzaldehydes in a supercritical carbon dioxide (80 .deg. C, 2,000 psi) containing THF entrainer (5%) in a 24 mL reactor proceed smoothly to yield olefination products in fairly good to excellent yields but slower, compared to reactions in a conventional THF solvent. Generally, phosphoranes that are not substituted with a nitro group show more (Z)-selective reactions with aromatic aldehydes under scCO 2 condition than in THF. The reaction of (benzylene)triphenylphosphosphoranes with 4-t-butylcyclohexanone gave the corresponding olefin compounds with a low conversion under both the supercritical carbon dioxide and the organic THF solvent. Our preliminary study showed the Wittig reaction carries out smoothly in supercritical carbon dioxide medium and also a possible tunability of this reaction pathway by adding a entrainer. The results would be useful for devising a novel process for the environmentally friendly Wittig reaction

  18. Ferricytochrome (c directly oxidizes aminoacetone to methylglyoxal, a catabolite accumulated in carbonyl stress.

    Directory of Open Access Journals (Sweden)

    Adriano Sartori

    Full Text Available Age-related diseases are associated with increased production of reactive oxygen and carbonyl species such as methylglyoxal. Aminoacetone, a putative threonine catabolite, is reportedly known to undergo metal-catalyzed oxidation to methylglyoxal, NH4(+ ion, and H2O2 coupled with (i permeabilization of rat liver mitochondria, and (ii apoptosis of insulin-producing cells. Oxidation of aminoacetone to methylglyoxal is now shown to be accelerated by ferricytochrome c, a reaction initiated by one-electron reduction of ferricytochrome c by aminoacetone without amino acid modifications. The participation of O2(•- and HO (• radical intermediates is demonstrated by the inhibitory effect of added superoxide dismutase and Electron Paramagnetic Resonance spin-trapping experiments with 5,5'-dimethyl-1-pyrroline-N-oxide. We hypothesize that two consecutive one-electron transfers from aminoacetone (E0 values = -0.51 and -1.0 V to ferricytochrome c (E0 = 0.26 V may lead to aminoacetone enoyl radical and, subsequently, imine aminoacetone, whose hydrolysis yields methylglyoxal and NH4(+ ion. In the presence of oxygen, aminoacetone enoyl and O2(•- radicals propagate aminoacetone oxidation to methylglyoxal and H2O2. These data endorse the hypothesis that aminoacetone, putatively accumulated in diabetes, may directly reduce ferricyt c yielding methylglyoxal and free radicals, thereby triggering redox imbalance and adverse mitochondrial responses.

  19. Sensitive SERS-pH sensing in biological media using metal carbonyl functionalized planar substrates.

    Science.gov (United States)

    Kong, Kien Voon; Dinish, U S; Lau, Weber Kam On; Olivo, Malini

    2014-04-15

    Conventional nanoparticle based Surface enhanced Raman scattering (SERS) technique for pH sensing often fails due to the aggregation of particles when detecting in acidic medium or biosamples having high ionic strength. Here, We develop SERS based pH sensing using a novel Raman reporter, arene chromium tricarbonyl linked aminothiophenol (Cr(CO)3-ATP), functionalized onto a nano-roughened planar substrates coated with gold. Unlike the SERS spectrum of the ATP molecule that dominates in the 400-1700 cm(-1) region, which is highly interfered by bio-molecules signals, metal carbonyl-ATP (Cr(CO)3)-ATP) offers the advantage of monitoring the pH dependent strong CO stretching vibrations in the mid-IR (1800-2200 cm(-1)) range. Raman signal of the CO stretching vibrations at ~1820 cm(-1) has strong dependency on the pH value of the environment, where its peak undergo noticeable shift as the pH of the medium is varied from 3.0 to 9.0. The sensor showed better sensitivity in the acidic range of the pH. We also demonstrate the pH sensing in a urine sample, which has high ionic strength and our data closely correlate to the value obtained from conventional sensor. In future, this study may lead to a sensitive chip based pH sensing platform in bio-fluids for the early diagnosis of diseases. © 2013 Published by Elsevier B.V.

  20. Synthesis, Antiproliferative, and Multidrug Resistance Reversal Activities of Heterocyclic α,β-Unsaturated Carbonyl Compounds.

    Science.gov (United States)

    Sun, Ju-Feng; Hou, Gui-Ge; Zhao, Feng; Cong, Wei; Li, Hong-Juan; Liu, Wen-Shuai; Wang, Chunhua

    2016-10-01

    A series of heterocyclic α,β-unsaturated carbonyl compounds (1a-1d, 2a-2d, 3a-3d, 4a-3d, and 5a-5d) with 1,5-diaryl-3-oxo-1,4-pentadienyl pharmacophore were synthesized for the development of anticancer and multidrug resistance reverting agents. The antiproliferative activities were tested against nine human cancer cell lines. Approximately 73% of the IC50 values were below 5 μm, while 35% of these figures were submicromolar, and compounds 3a-3d with 4-trifluoro methyl in the arylidene benzene rings were the most potent, since their IC50 values are between 0.06 and 3.09 μm against all cancer cell lines employed. Meanwhile, their multidrug resistance reversal properties and cellular uptake were further examined. The data displayed that all of these compounds could reverse multidrug resistance, particularly, compounds 3a and 4a demonstrated both potent multidrug resistance reverting properties and strong antiproliferative activities, which can be taken as leading molecules for further research of dual effect agents in tumor chemotherapy. © 2016 John Wiley & Sons A/S.

  1. Synthesis procedure for routine production of [carbonyl-{sup 11}C]desmethyl-WAY-100635

    Energy Technology Data Exchange (ETDEWEB)

    Maiti, Dilip K. [Department of Pediatrics, School of Medicine, PET Center, Children' s Hospital of Michigan, Wayne State University, 3901 Beaubien Blvd., Detroit, MI 48201 (United States); Chakraborty, Pulak K. [Department of Radiology, School of Medicine, PET Center, Children' s Hospital of Michigan, Wayne State University, 3901 Beaubien Blvd., Detroit, MI 48201 (United States)]. E-mail: pulak@pet.wayne.edu; Chugani, Diane C. [Department of Pediatrics, School of Medicine, PET Center, Children' s Hospital of Michigan, Wayne State University, 3901 Beaubien Blvd., Detroit, MI 48201 (United States); Department of Radiology, School of Medicine, PET Center, Children' s Hospital of Michigan, Wayne State University, 3901 Beaubien Blvd., Detroit, MI 48201 (United States); Muzik, Otto [Department of Pediatrics, School of Medicine, PET Center, Children' s Hospital of Michigan, Wayne State University, 3901 Beaubien Blvd., Detroit, MI 48201 (United States); Department of Radiology, School of Medicine, PET Center, Children' s Hospital of Michigan, Wayne State University, 3901 Beaubien Blvd., Detroit, MI 48201 (United States); Mangner, Thomas J. [Department of Radiology, School of Medicine, PET Center, Children' s Hospital of Michigan, Wayne State University, 3901 Beaubien Blvd., Detroit, MI 48201 (United States); Chugani, Harry T. [Department of Pediatrics, School of Medicine, PET Center, Children' s Hospital of Michigan, Wayne State University, 3901 Beaubien Blvd., Detroit, MI 48201 (United States); Department of Radiology, School of Medicine, PET Center, Children' s Hospital of Michigan, Wayne State University, 3901 Beaubien Blvd., Detroit, MI 48201 (United States); Department of Neurology, School of Medicine, PET Center, Children' s Hospital of Michigan, Wayne State University, 3901 Beaubien Blvd., Detroit, MI 48201 (United States)

    2005-05-01

    An improved one-pot synthesis procedure for routine production of [carbonyl-{sup 11}C]desmethyl-WAY-100635 ([{sup 11}C]DWAY) is described. An efficient purification of the crude product has also been developed and was accomplished by C-18 reversed-phase semi-preparative HPLC using 55/45 EtOH-NaH{sub 2}PO{sub 4} buffer (20mM, pH=6.5) as the eluent. The desired product fraction was collected in a 2.0-2.5mL volume and formulated with 11mL of 0.9% saline. The radioligand was ready for human use in 45min (EOB). The product was obtained with a radiochemical yield of 11.1+/-1.8% (EOB, n=15) with a radiochemical purity of >99%. Specific activity was 133.2-185.0GBq/{mu}mol (3.6-5.0Ci/{mu}mol, EOS, n=2) when ca. 37.0GBq (ca. 1.0Ci) of starting [{sup 11}C]CO{sub 2} was used. Unlabeled mass of [{sup 11}C]DWAY was found to be 0.15-0.24{mu}g/mL and the precursor was present in less than 50ng/mL in final production solution.

  2. The Drosophila carbonyl reductase sniffer prevents oxidative stress-induced neurodegeneration.

    Science.gov (United States)

    Botella, Jose A; Ulschmid, Julia K; Gruenewald, Christoph; Moehle, Christoph; Kretzschmar, Doris; Becker, Katja; Schneuwly, Stephan

    2004-05-04

    A growing body of evidence suggests that oxidative stress is a common underlying mechanism in the pathogenesis of neurodegenerative disorders such as Alzheimer's, Huntington's, Creutzfeld-Jakob and Parkinson's diseases. Despite the increasing number of reports finding a causal relation between oxidative stress and neurodegeneration, little is known about the genetic elements that confer protection against the deleterious effects of oxidation in neurons. We have isolated and characterized the Drosophila melanogaster gene sniffer, whose function is essential for preventing age-related neurodegeneration. In addition, we demonstrate that oxidative stress is a direct cause of neurodegeneration in the Drosophila central nervous system and that reduction of sniffer activity leads to neuronal cell death. The overexpression of the gene confers neuronal protection against oxygen-induced apoptosis, increases resistance of flies to experimental normobaric hyperoxia, and improves general locomotor fitness. Sniffer belongs to the family of short-chain dehydrogenase/reductase (SDR) enzymes and exhibits carbonyl reductase activity. This is the first in vivo evidence of the direct and important implication of this enzyme as a neuroprotective agent in the cellular defense mechanisms against oxidative stress.

  3. Emissions of polyciclic aromatic hydrocarbons and polyciclic carbonyl biphenils from electric arc furnaces

    Directory of Open Access Journals (Sweden)

    P. Gomes, J. F.

    2008-06-01

    Full Text Available This paper describes work done in order to determine the emissions of highly toxic organic micropollutants from electric arc furnaces used in the production of carbon steel from scrap. The study will be allowing to derive relationships between the levels of airborne micropollutants and the operational parameters of the production process so that an abatement of pollution could be achieved. By using the European standard method CEN 1948 for dioxin like compounds sampling and measurement, it was possible to determine the characteristic fingerprint of micropollutants such as polyciclic aromatic hydrocarbons (PAHs and polycyclic carbonyl biphenils (PCBs emitted by this particular stationary source.

    Este artículo contiene resultados del trabajo ejecutado para estudiar la determinación de las emisiones de los micropolutantes orgánicos muy tóxicos que se emiten por los hornos eléctricos de arco utilizados en la producción de acero. Este estudio inicial va a permitir relacionar las concentraciones de polutantes emitidos a la atmósfera con las condiciones de operación del horno eléctrico de arco. Utilizando el método normalizado CEN 1948 para captación y análisis de muestras de compuestos análogos a las dioxinas ha sido posible determinar el perfil característico de los micropolutantes tales como PAHs y PCBs emitidos por esta fuente.

  4. The Effect of Temperature on Selectivity in the Oscillatory Mode of the Phenylacetylene Oxidative Carbonylation Reaction.

    Science.gov (United States)

    Parker, Julie; Novakovic, Katarina

    2017-08-05

    Reaction temperature plays a major role in product selectivity in the oscillatory mode of the palladium-catalyzed phenylacetylene oxidative carbonylation reaction. At 40 °C, dimethyl (2Z)-2-phenyl-2-butenedioate is the major product whereas at 0 °C the major product is 5,5-dimethoxy-3-phenyl-2(5H)-furanone. The occurrence of oscillations in pH coincides with an increase in the rate of phenylacetylene consumption and associated product formation. Experiments were performed isothermally in a reaction calorimeter to correlate reactant consumption and product formation with the occurrence of pH oscillations and the heat released by the reaction. An increase in the size of the pH drop in a single oscillation correlates with an increase in energy, indicating that this section of a single oscillation relates to reactant consumption. Based on these observations, a reaction pathway responsible for product formation is provided. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  5. Effect of the carbonyl iron particles on acoustic absorption properties of magnetic polyurethane foam

    Science.gov (United States)

    Geng, Jialu; Wang, Caiping; Zhu, Honglang; Wang, Xiaojie

    2018-03-01

    Elastomeric matrix embedded with magnetic micro-sized particles has magnetically controllable properties, which has been investigated extensively in the last decades. In this study we develop a new magnetically controllable elastomeric material for acoustic applications at lower frequencies. The soft polyurethane foam is used as matrix material due to its extraordinary elastic and acoustic absorption properties. One-step method is used to synthesize polyurethane foam, in which all components including polyether polyols 330N, MDI, deionized water, silicone oil, carbonyl iron particle (CIP) and catalyst are put into one container for curing. Changing any component can induce the change of polyurethane foam's properties, such as physical and acoustic properties. The effect of the content of MDI on acoustic absorption is studied. The CIPs are aligned under extra magnetic field during the foaming process. And the property of polyurethane foam with aligned CIPs is also investigated. Scanning electron microscope (SEM) is used to observe the structure of pore and particle-chain. The two-microphone impedance tube and the transfer function method are used to test acoustic absorption property of the magnetic foams.

  6. Fourier Transform Spectroscopy of 18O-Enriched Carbonyl Sulfide from 1825 to 2700 cm -1

    Science.gov (United States)

    Strugariu, T.; Naı̈m, S.; Fayt, A.; Bredohl, H.; Blavier, J.-F.; Dubois, I.

    1998-06-01

    We have measured the Fourier transform spectrum of carbonyl sulfide from 1825 to 2700 cm-1, using a sample enriched in both18O (94.0%) and17O (1.54%). A careful calibration yields a line-position accuracy between 1.5 and 3.0 10-5cm-1. We have observed and analyzed 118 infrared bands of which 93 are measured for the first time: 55 for18O12C32S, 20 for18O12C34S, 11 for18O12C33S, 1 for18O12C36S, 12 for17O12C32S, 4 for17O12C34S, 2 for17O12C33S, and 13 for18O13C32S. Intensities are also reported and analyzed for all those bands. The intensity accuracy is better than 10%, and the precision of approximately 1% allows us to determine some Herman-Wallis coefficients.

  7. Reaction of phosphorus ylides with carbonyl compounds in supercritical carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Kyung Il; Kim, Hak Do; Shim, Jae Jin; Ra, Choon Sup [Yeungnam Univ., Gyongsan (Korea, Republic of)

    2004-02-15

    The condensation reaction of (benzylene)triphenylphosphoranes with carbonyl compounds in supercritical carbon dioxide was examined. Reactions of (benzylene)phosphoranes (ca. 1 mmol) with several benzaldehydes in a supercritical carbon dioxide (80 .deg. C, 2,000 psi) containing THF entrainer (5%) in a 24 mL reactor proceed smoothly to yield olefination products in fairly good to excellent yields but slower, compared to reactions in a conventional THF solvent. Generally, phosphoranes that are not substituted with a nitro group show more (Z)-selective reactions with aromatic aldehydes under scCO{sub 2} condition than in THF. The reaction of (benzylene)triphenylphosphosphoranes with 4-t-butylcyclohexanone gave the corresponding olefin compounds with a low conversion under both the supercritical carbon dioxide and the organic THF solvent. Our preliminary study showed the Wittig reaction carries out smoothly in supercritical carbon dioxide medium and also a possible tunability of this reaction pathway by adding a entrainer. The results would be useful for devising a novel process for the environmentally friendly Wittig reaction.

  8. The Field-Dependent Rheological Properties of Magnetorheological Grease Based on Carbonyl-Iron-Particles

    Science.gov (United States)

    Mohamad, N.; Mazlan, S. A.; Ubaidillah; Choi, Seung-Bok; Nordin, M. F. M.

    2016-09-01

    This paper presents dynamic viscoelastic properties of magnetorheological (MR) grease under variation of magnetic fields and magnetic particle fractions. The tests to discern the field-dependent properties are undertaken using both rotational and oscillatory shear rheometers. As a first step, the MR grease is developed by dispersing the carbonyl iron (CI) particles into grease medium with a mechanical stirrer. Experimental data are obtained by changing the magnetic field from 0 to 0.7 T at room temperature of 25 °C. It is found that a strong Payne effect limits the linear viscoelastic region of MR grease at strains above 0.1%. The results exhibit a high dynamic yield stress which is equivalent to Bingham plastic rheological model, and show relatively good MR effect at high shear rate of 2000 s-1. In addition, high dispersion of the magnetic particles and good thermal properties are proven. The results presented in this work directly indicate that MR grease is a smart material candidate that could be widely applicable to various fields including vibration control.

  9. Cholesteryl-coated carbonyl iron particles with improved anti-corrosion stability and their viscoelastic behaviour under magnetic field

    Czech Academy of Sciences Publication Activity Database

    Mrlik, M.; Ilčíková, M.; Sedlačík, M.; Mosnáček, J.; Peer, Petra; Filip, Petr

    2014-01-01

    Roč. 292, č. 9 (2014), s. 2137-2143 ISSN 0303-402X R&D Projects: GA ČR(CZ) GP14-32114P Grant - others:GA MŠk(CZ) ED2.1.00/03.0111 Institutional support: RVO:67985874 Keywords : carbonyl iron * cholesteryl chloroformate * silicone oil suspensions * viscoelasticity * magnetorheology Subject RIV: BK - Fluid Dynamics Impact factor: 1.865, year: 2014

  10. Levels of protein hydroperoxides and carbonyl groups in guinea pigs native of high altitudes (Huancavelica, 3660 m)

    OpenAIRE

    Huayta, Roxana; Zúñiga, Haydée; Esquerre, Cynthia; Hernández, Luz; Carranza, Elizabeth

    2014-01-01

    The influence of hypobaric hypoxia on protein oxidation in lungs, heart, liver, kidneys and testicles of high altitude native guinea pigs (Huancavelica, 3660 m) in comparison to sea level (Lima, 150 m) native guinea pigs was evaluated. The concentration of protein hydroperoxides (POOH) and carbonyl groups (GC) as markers of protein oxidation, as well as total thiols (TT) concentration, powerful reducing agents that act as live antioxidants were determined. The results showed low concentration...

  11. Increased nitration and carbonylation of proteins in MRL +/+ mice exposed to trichloroethene: Potential role of protein oxidation in autoimmunity

    International Nuclear Information System (INIS)

    Wang Gangduo; Wang Jianling; Ma Huaxian; Khan, M. Firoze

    2009-01-01

    Even though reactive oxygen and nitrogen species (RONS) are implicated as mediators of autoimmune diseases (ADs), little is known about contribution of protein oxidation (carbonylation and nitration) in the pathogenesis of such diseases. The focus of this study was, therefore, to establish a link between protein oxidation and induction and/or exacerbation of autoimmunity. To achieve this, female MRL +/+ mice were treated with trichloroethene (TCE), an environmental contaminant known to induce autoimmune response, for 6 or 12 weeks (10 mmol/kg, i.p., every 4 th day). TCE treatment resulted in significantly increased formation of nitrotyrosine (NT) and induction of iNOS in the serum at both 6 and 12 weeks of treatment, but the response was greater at 12 weeks. Likewise, TCE treatment led to greater NT formation, and iNOS protein and mRNA expression in the livers and kidneys. Moreover, TCE treatment also caused significant increases (∼3 fold) in serum protein carbonyls (a marker of protein oxidation) at both 6 and 12 weeks. Significantly increased protein carbonyls were also observed in the livers and kidneys (2.1 and 1.3 fold, respectively) at 6 weeks, and to a greater extent at 12 weeks (3.5 and 2.1 fold, respectively) following TCE treatment. The increases in TCE-induced protein oxidation (carbonylation and nitration) were associated with significant increases in Th1 specific cytokine (IL-2, IFN-γ) release into splenocyte cultures. These results suggest an association between protein oxidation and induction/exacerbation of autoimmune response. The results present a potential mechanism by which oxidatively modified proteins could contribute to TCE-induced autoimmune response and necessitates further investigations for clearly establishing the role of protein oxidation in the pathogenesis of ADs.

  12. Binding of the 9-O-N-aryl/arylalkyl amino carbonyl methyl substituted berberine analogs to tRNA(phe..

    Directory of Open Access Journals (Sweden)

    Anirban Basu

    Full Text Available BACKGROUND: Three new analogs of berberine with aryl/ arylalkyl amino carbonyl methyl substituent at the 9-position of the isoquinoline chromophore along with berberrubine were studied for their binding to tRNA(phe by wide variety of biophysical techniques like spectrophotometry, spectrofluorimetry, circular dichroism, thermal melting, viscosity and isothermal titration calorimetry. METHODOLOGY/ PRINCIPAL FINDINGS: Scatchard binding isotherms revealed that the cooperative binding mode of berberine was propagated in the analogs also. Thermal melting studies showed that all the 9-O-N-aryl/arylalkyl amino carbonyl methyl substituted berberine analogs stabilized the tRNA(phe more in comparison to berberine. Circular dichroism studies showed that these analogs perturbed the structure of tRNA(phe more in comparison to berberine. Ferrocyanide quenching studies and viscosity results proved the intercalative binding mode of these analogs into the helical organization of tRNA(phe. The binding was entropy driven for the analogs in sharp contrast to the enthalpy driven binding of berberine. The introduction of the aryl/arylalkyl amino carbonyl methyl substituent at the 9-position thus switched the enthalpy driven binding of berberine to entropy dominated binding. Salt and temperature dependent calorimetric studies established the involvement of multiple weak noncovalent interactions in the binding process. CONCLUSIONS/ SIGNIFICANCE: The results showed that 9-O-N-aryl/arylalkyl amino carbonyl methyl substituted berberine analogs exhibited almost ten folds higher binding affinity to tRNA(phe compared to berberine whereas the binding of berberrubine was dramatically reduced by about twenty fold in comparison to berberine. The spacer length of the substitution at the 9-position of the isoquinoline chromophore appears to be critical in modulating the binding affinities towards tRNA(phe.

  13. [1,3-Bis(diphenyl­phosphino)pentane-κ2 P,P′]tetra­carbonyl­chromium(0)

    Science.gov (United States)

    Shawkataly, Omar bin; Thangadurai, Daniel T.; Pankhi, Mohd. Aslam A.; Shahinoor Dulal Islam, S. M.; Fun, Hoong-Kun

    2009-01-01

    In the title compound, [Cr(C29H30P2)(CO)4], the Cr atom is octa­hedrally coordinated by four carbonyl ligands and one bidentate phosphine ligand, which is bounded as a chelate in a cis position. The average Cr—P and Cr—C bond lengths are 2.377 and 1.865 Å, respectively. PMID:21582044

  14. Synthesis and magnetorheological characteristics of ribbon-like, polypyrrole-coated carbonyl iron suspensions under oscillatory shear

    Czech Academy of Sciences Publication Activity Database

    Mrlik, M.; Sedlačík, M.; Pavlinek, V.; Bažant, P.; Sáha, P.; Peer, Petra; Filip, Petr

    2013-01-01

    Roč. 128, č. 5 (2013), s. 2977-2982 ISSN 0021-8995 Grant - others:GA MŠk(CZ) ED2.1.00/03.0111; UTB Zlín(CZ) IGA/1/FT/11/D Institutional support: RVO:67985874 Keywords : carbonyl iron * core-shell * magnetorheological fluid * polypyrrole * viscoelasticity * ribbon-like particles Subject RIV: BK - Fluid Dynamics Impact factor: 1.640, year: 2013

  15. Synthesis and magnetorheological characteristics of ribbon-like, polypyrrole-coated carbonyl iron suspensions under oscillatory shear

    Czech Academy of Sciences Publication Activity Database

    Mrlik, M.; Sedlačík, M.; Pavlinek, V.; Bažant, P.; Sáha, P.; Peer, Petra; Filip, Petr

    2013-01-01

    Roč. 128, č. 5 (2013), s. 2977-2982 ISSN 0021-8995 Grant - others:GA MŠk(CZ) ED2.1.00/03.0111; UTB Zlín(CZ) IGA/1/FT/11/D Institutional support: RVO:67985874 Keywords : carbonyl iron * core - shell * magnetorheological fluid * polypyrrole * viscoelasticity * ribbon-like particles Subject RIV: BK - Fluid Dynamics Impact factor: 1.640, year: 2013

  16. Improved thermooxidation and sedimentation stability of covalently-coated carbonyl iron particles with cholesteryl groups and their influence on magnetorheology

    Czech Academy of Sciences Publication Activity Database

    Mrlík, M.; Ilčíková, M.; Pavlínek, V.; Mosnáček, J.; Peer, Petra; Filip, Petr

    2013-01-01

    Roč. 396, april (2013), s. 146-151 ISSN 0021-9797 R&D Projects: GA ČR GA202/09/1626 Grant - others:GA MŠk(CZ) ED2.1.00/03.0111 Institutional support: RVO:67985874 Keywords : covalent coating * carbonyl iron * cholesteryl chloroformate * thermooxidation * Magnetorheology Subject RIV: BK - Fluid Dynamics Impact factor: 3.552, year: 2013

  17. Amberlyst-15: An Efficient and reusable heterogeneous catalyst for the synthesis of β-amino carbonyl compounds

    Directory of Open Access Journals (Sweden)

    Pathakota Venkata Ramana

    2015-12-01

    Full Text Available A simple and efficient method has been developed for the synthesis of β-amino carbonyl compounds from aromatic ketones, aldehydes and amines by Mannich reaction in the presence of amberlyst-15 as a reusable heterogeneous catalyst at room temperature under solvent-free conditions. The noteworthy advantages of the present method are short reaction times, good product yields, simple procedures and use of non-toxic catalyst.

  18. General and Efficient a-Oxygenation of Carbonyl Compounds by TEMPO Induced by Single-Electron-Transfer Oxidation of Their Enolates

    Czech Academy of Sciences Publication Activity Database

    Dinca, E.; Hartmann, P.; Smrček, Jakub; Dix, I.; Jones, P. G.; Jahn, Ullrich

    -, č. 24 (2012), s. 4461-4482 ISSN 1434-193X Institutional support: RVO:61388963 Keywords : carbonyl compounds * oxidation * radicals * electron transfer * enolates Subject RIV: CC - Organic Chemistry Impact factor: 3.344, year: 2012

  19. (II) complexes as sensitizers for dye sensitized solar cells

    Indian Academy of Sciences (India)

    dimethyl-3-propyl-1 H-imidazol-3-ium iodide (DMPII),. 4-tert-butyl-pyridine (TBP) and ... cymene) ruthenium(II) dimer was synthesized according to the reported ... saturated ammonium chloride (200 ml) solution was added to decompose the ...

  20. Conduction properties of KcsA measured using brownian dynamics with flexible carbonyl groups in the selectivity filter.

    Science.gov (United States)

    Chung, Shin-Ho; Corry, Ben

    2007-07-01

    In the narrow segment of an ion conducting pathway, it is likely that a permeating ion influences the positions of the nearby atoms that carry partial or full electronic charges. Here we introduce a method of incorporating the motion of charged atoms lining the pore into Brownian dynamics simulations of ion conduction. The movements of the carbonyl groups in the selectivity filter of the KcsA channel are calculated explicitly, allowing their bond lengths, bond angles, and dihedral angels to change in response to the forces acting upon them. By systematically changing the coefficients of bond stretching and of angle bending, the carbon and oxygen atoms can be made to fluctuate from their fixed positions by varying mean distances. We show that incorporating carbonyl motion in this way does not alter the mechanism of ion conduction and only has a small influence on the computed current. The slope conductance of the channel increases by approximately 25% when the root mean-square fluctuations of the carbonyl groups are increased from 0.01 to 0.61 A. The energy profiles and the number of resident ions in the channel remain unchanged. The method we utilized here can be extended to allow the movement of glutamate or aspartate side chains lining the selectivity filters of other ionic channels.