WorldWideScience

Sample records for benzyl radicals

  1. Resonance Raman study of benzyl radical

    DEFF Research Database (Denmark)

    Langkilde, F.W.; Bajdor, K.; Wilbrandt, R.

    1992-01-01

    Time-resolved resonance Raman spectra are obtained of benzyl radicals created by laser flash photolysis of benzylchloride and diphenylacetone in solution. The spectra are obtained in resonance with the intense 2 2A2-1 B-2(2) transition of benzyl. The strong Raman bands are assigned to totally...... symmetric a1 modes. The remaining observed bands are tentatively assigned to fundamental modes of b1, a2, and b2 symmetry, and to overtones and combinations. The resonance Raman spectra are found to be quite different from previous fluorescence spectra of benzyl, and the origins of these differences are...

  2. Thermal Decomposition of Benzyl Radical via Multiple Active Pathways

    Science.gov (United States)

    Buckingham, Grant; Robichaud, David; Ormond, Thomas; Nimlos, Mark R.; Daily, John W.; Ellison, Barney

    2014-06-01

    The thermal decomposition of benzyl radical (C6H5CH2) has been investigated using a combination infrared absorption spectroscopy in a neon matrix and 118.2 (10.487 eV) photoionization mass spectrometry. Both techniques are coupled with a heated tubular reactor to allow temperature control over the decomposition to indicate relative barrier heights of fragmentation pathways. Three possible chemical mechanisms have been considered. 1) Ring expansion to cycloheptatrienyl radical (C7H7) with subsequent breakdown to HCCH and C5H5, 2) isomerization to the substituted five-membered ring fulvenallene (C5H4=C=CH2), which is of interest to kinetic theorists and finally 3) hydrogen shift to form methyl-substituted phenyl radical, which can then form ortho-benzyne, diacetylene and other fragments. Benzyl radical is generated from two precursors, C6H5CH2CH3 and C6H5CH2Br, and both lead to the appearance of HCCH and C5H5. At slightly hotter temperatures peaks are observed at m/z 90, presumed to be C5H4=C=CH2, and 89, potentially the substituted propargyl C5H4=C=CH. Additionally, decomposition of isotopically substituted parent molecules C6H5CD2CD3 and C6D5CH2CH3 indicates C7H7 as an intermediate due to H/D ratios in fragment molecules.

  3. Vibronic Emission Spectroscopy of Benzyl-Type Radicals Generated by Corona Discharge

    Science.gov (United States)

    Yi, Eun Hye; Yoon, Young; Lee, Sang

    2014-06-01

    Benzyl radical is a prototypical aromatic free radical and has been the subject of numerous spectroscopic studies. On the other hand, ring-substituted benzyl radicals, benzyl-type radicals, have received less attention due to the difficulties associated with production in corona discharge and analysis of spectra. We report vibronic emission spectra of hetero halogen multi-substituted benzyl radicals generated by corona discharge of corresponding toluene derivatives using a pinhole-type glass nozzle, from which visible vibronic emission spectra were recorded using a long-path monochromator. The spectra show nice features of strongest origin band and a series of vibronic bands in the lower energies originating from the vibrationless D_1 state. From the analysis of the spectra observed, we determined the energies of the D_1 → D_0 electronic transition and vibrational mode frequencies in the ground electronic state. On the other hand, all substituted benzyl radicals show the origin bands shifted to red region with respect to the parental benzyl radical at 22002 cm-1. The shifts of multi-substituted benzyl radicals can be well estimated using the method developed from mono-substituted benzyl radicals as well as the positions of nodal point and mutual orientation of substituents, which could be useful for scientists to set a proper scanning range of their spectrometers for the spectroscopic observation of transient molecules. In this presentation, we will discuss the substituent effect on electronic transition energy and the experimental technique developed in this laboratory. Y. W. Yoon and S. K. Lee, J. Phys. Chem. A, 117, 2485 (2013). Y. W. Yoon, S. Y. Chae, and S. K. Lee, Chem. Phys. Lett., 584, 37 (2013). Y. W. Yoon and S. K. Lee, Chem. Phys. Lett., 570, 29 (2013).

  4. The thermal decomposition of the benzyl radical in a heated micro-reactor. II. Pyrolysis of the tropyl radical

    Energy Technology Data Exchange (ETDEWEB)

    Buckingham, Grant T. [Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, USA; National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden Colorado 80401, USA; Porterfield, Jessica P. [Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, USA; Kostko, Oleg [Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA; Troy, Tyler P. [Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA; Ahmed, Musahid [Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA; Robichaud, David J. [National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden Colorado 80401, USA; Nimlos, Mark R. [National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden Colorado 80401, USA; Daily, John W. [Department of Mechanical Engineering, Center for Combustion and Environmental Research, University of Colorado, Boulder, Colorado 80309-0427, USA; Ellison, G. Barney [Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, USA

    2016-07-05

    Cycloheptatrienyl (tropyl) radical, C7H7, was cleanly produced in the gas-phase, entrained in He or Ne carrier gas, and subjected to a set of flash-pyrolysis micro-reactors. The pyrolysis products resulting from C7H7 were detected and identified by vacuum ultraviolet photoionization mass spectrometry. Complementary product identification was provided by infrared absorption spectroscopy. Pyrolysis pressures in the micro-reactor were roughly 200 Torr and residence times were approximately 100 us. Thermal cracking of tropyl radical begins at 1100 K and the products from pyrolysis of C7H7 are only acetylene and cyclopentadienyl radicals. Tropyl radicals do not isomerize to benzyl radicals at reactor temperatures up to 1600 K. Heating samples of either cycloheptatriene or norbornadiene never produced tropyl (C7H7) radicals but rather only benzyl (C6H5CH2). The thermal decomposition of benzyl radicals has been reconsidered without participation of tropyl radicals. There are at least three distinct pathways for pyrolysis of benzyl radical: the Benson fragmentation, the methyl-phenyl radical, and the bridgehead norbornadienyl radical. These three pathways account for the majority of the products detected following pyrolysis of all of the isotopomers: C6H5CH2, C6H5CD2, C6D5CH2, and C6H5 13CH2. Analysis of the temperature dependence for the pyrolysis of the isotopic species (C6H5CD2, C6D5CH2, and C6H5 13CH2) suggests the Benson fragmentation and the norbornadienyl pathways open at reactor temperatures of 1300 K while the methyl-phenyl radical channel becomes active at slightly higher temperatures (1500 K).

  5. The thermal decomposition of the benzyl radical in a heated micro-reactor. II. Pyrolysis of the tropyl radical

    Science.gov (United States)

    Buckingham, Grant T.; Porterfield, Jessica P.; Kostko, Oleg; Troy, Tyler P.; Ahmed, Musahid; Robichaud, David J.; Nimlos, Mark R.; Daily, John W.; Ellison, G. Barney

    2016-07-01

    Cycloheptatrienyl (tropyl) radical, C7H7, was cleanly produced in the gas-phase, entrained in He or Ne carrier gas, and subjected to a set of flash-pyrolysis micro-reactors. The pyrolysis products resulting from C7H7 were detected and identified by vacuum ultraviolet photoionization mass spectrometry. Complementary product identification was provided by infrared absorption spectroscopy. Pyrolysis pressures in the micro-reactor were roughly 200 Torr and residence times were approximately 100 μs. Thermal cracking of tropyl radical begins at 1100 K and the products from pyrolysis of C7H7 are only acetylene and cyclopentadienyl radicals. Tropyl radicals do not isomerize to benzyl radicals at reactor temperatures up to 1600 K. Heating samples of either cycloheptatriene or norbornadiene never produced tropyl (C7H7) radicals but rather only benzyl (C6H5CH2). The thermal decomposition of benzyl radicals has been reconsidered without participation of tropyl radicals. There are at least three distinct pathways for pyrolysis of benzyl radical: the Benson fragmentation, the methyl-phenyl radical, and the bridgehead norbornadienyl radical. These three pathways account for the majority of the products detected following pyrolysis of all of the isotopomers: C6H5CH2, C6H5CD2, C6D5CH2, and C6H513CH2. Analysis of the temperature dependence for the pyrolysis of the isotopic species (C6H5CD2, C6D5CH2, and C6H513CH2) suggests the Benson fragmentation and the norbornadienyl pathways open at reactor temperatures of 1300 K while the methyl-phenyl radical channel becomes active at slightly higher temperatures (1500 K).

  6. The First Example of Cation Radical Induced Ether Cleavage of Benzyl Phenyl Ether

    International Nuclear Information System (INIS)

    A thermally stable benzyl phenyl ether has been shown to cleavage under mild conditions. The new reaction described herein further expands the chemistry of the ether cleavage by cation radicals. Over the last several years, our lab has discovered cation radical-induced oxidative C-O bond cleavages such as carbonates (eq 1), carbamates (eq 2), peroxides (eq 3), and alcohols (eq 4), where R is either tert-butyl or benzyl. It was recognized from those reactions that carbocationic chemistry with C-O bond cleavages was predominant, with a 2:1 stoichiometry of Th+·:oxidized molecules

  7. Spectroscopic identification of benzyl-type radicals generated by corona discharge of 2-chloro-4-fluorotoluene.

    Science.gov (United States)

    Huh, Chang Soon; Yoon, Young Wook; Lee, Sang Kuk

    2012-05-01

    By means of a technique of corona excited supersonic expansion coupled with a pinhole-type glass nozzle, we generated vibronically excited but jet-cooled benzyl-type radicals from precursor 2-chloro-4-fluorotoluene seeded in a large amount of inert carrier gas He. From an analysis of the visible vibronic emission spectrum, we found evidence of the formation of the 2-chloro-4-fluorobenzyl and 4-fluorobenzyl radicals. A possible pathway for the formation of these benzyl-type radicals is herein proposed. Also, the electronic energy in the D(1) → D(0) transition and the vibrational mode frequencies of the 2-chloro-4-fluorobenzyl radical in the ground electronic state were accurately determined, for the first time, by comparison with ab initio calculations and the known vibrational data of the precursor. PMID:22583229

  8. Polycyclic aromatic hydrocarbon (PAH) formation from benzyl radicals: a reaction kinetics study.

    Science.gov (United States)

    Sinha, Sourab; Raj, Abhijeet

    2016-03-01

    The role of resonantly stabilized radicals such as propargyl, cyclopentadienyl and benzyl in the formation of aromatic hydrocarbons such as benzene and naphthalene in the high temperature environments has been long known. In this work, the possibility of benzyl recombination to form three-ring aromatics, phenanthrene and anthracene, is explored. A reaction mechanism for it is developed, where reaction energetics are calculated using density functional theory (B3LYP functional with 6-311++G(d,p) basis set) and CBS-QB3, while temperature-dependent reaction kinetics are evaluated using transition state theory. The mechanism begins with barrierless formation of bibenzyl from two benzyl radicals with the release of 283.2 kJ mol(-1) of reaction energy. The further reactions involve H-abstraction by a H atom, H-desorption, H-migration, and ring closure to gain aromaticity. Through mechanism and rate of production analyses, the important reactions leading to phenanthrene and anthracene formation are determined. Phenanthrene is found to be the major product at high temperatures. Premixed laminar flame simulations are carried out by including the proposed reactions for phenanthrene formation from benzyl radicals and compared to experimentally observed species profiles to understand their effects on species concentrations. PMID:26923612

  9. CONTROLLED RADICAL COPOLYMERIZATION OF STYRENE AND MALEIC ANHYDRIDE UNDER GAMMA RADIATION IN THE PRESENCE OF BENZYL DITHIOBENZOATE

    Institute of Scientific and Technical Information of China (English)

    De-cheng Wu; Ying-fang Zou; Cai-yuan Pan

    2002-01-01

    The copolymerization of styrene (St) with maleic anhydride (MAh) under gamma radiation at room temperature inthe presence of benzyl dithiobenzoate (BDTB) was found to display "living" nature evidenced by constant concentration ofchain radicals during the copolymerization, linear evolution of molecular weights with conversion and narrow molecularweight distribution (Mw/Mn = 1.23-1.35). The compositional analysis and the sequence structural information of thecopolymers obtained from DEPT (Distortionless Enhancement by Polarization Transfer) experiments demonstrate that thecopolymers obtained also possess strictly alternating structure.

  10. Spectroscopic identification of isomeric jet-cooled benzyl-type radicals formed from 3-fluoro-o-xylene by corona discharge

    Science.gov (United States)

    Yoon, Young Wook; Chae, Sang Youl; Lee, Sang Kuk

    2013-10-01

    By means of a pinhole-type glass nozzle designed for supersonic jet expansion along with corona discharge, vibronically excited but jet-cooled isomeric benzyl-type radicals were generated from the precursor 3-fluoro-o-xylene. The visible vibronic emission spectrum was recorded from the discharge system with a long-path monochromator. From an analysis of the spectrum observed, we identified the formation of two isomers, 2-methyl-3-fluorobenzyl and 2-methyl-6-fluorobenzyl radicals in the corona discharge of precursor, and determined for the first time the electronic energy in the D1 → D0 transition and vibrational mode frequencies in the D0 state for both isomers.

  11. Antimicrobial, free radical scavenging activities and catalytic oxidation of benzyl alcohol by nano-silver synthesized from the leaf extract of Aristolochia indica L.: a promenade towards sustainability

    Science.gov (United States)

    Shanmugam, C.; Sivasubramanian, G.; Parthasarathi, Bera; Baskaran, K.; Balachander, R.; Parameswaran, V. R.

    2015-07-01

    Silver nanoparticles (Ag-NPs) were synthesized from aqueous silver nitrate through a simple route using the leaf extract of Aristolochia indica L. (LAIL) which acted as a reducing as well as capping agent. X-ray diffraction confirmed that the synthesized silver particles have a face centred cubic structure. EDS predicted the presence of elemental silver. The SEM images showed the synthesis of spherically mono-dispersed particles, with nano dimensions accounted by the TEM images. Infra-red spectrum adopted to the different organic functionalities present at the surface of the particles. TGA indicated an overall 11 % weight loss up to 1000 °C, suggesting desorption of biomolecules from the surface. X-ray photoelectron spectroscopy (XPS) analysis revealed the presence of metallic silver nanoparticles. The prepared material was utilized as catalyst in the oxidation of benzyl alcohol with molecular oxygen as the oxidant in methanol, under ambient conditions of temperature and pressure. Also Ag-NPs showed good to moderate anti-microbial activity employing the Agar disc diffusion method against various strains using Ciprofloxacin and Fluconazole as standard. Free radical scavenging activity of the nanoparticles were observed by modified 1,1-diphynyl-2-picrylhydrazyl, DPPH and 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), ABTS in vitro assays. The work presented here demonstrates the adaptability of the synthesized Ag-NPs in participating as a disinfectant agent, free radical scavenger and an effective oxidation catalyst. The basic premise of attaining sustainability through the green synthesis of smart multifaceted materials has been consciously addressed.

  12. Antimicrobial, free radical scavenging activities and catalytic oxidation of benzyl alcohol by nano-silver synthesized from the leaf extract of Aristolochia indica L.: a promenade towards sustainability

    Science.gov (United States)

    Shanmugam, C.; Sivasubramanian, G.; Parthasarathi, Bera; Baskaran, K.; Balachander, R.; Parameswaran, V. R.

    2016-06-01

    Silver nanoparticles (Ag-NPs) were synthesized from aqueous silver nitrate through a simple route using the leaf extract of Aristolochia indica L. (LAIL) which acted as a reducing as well as capping agent. X-ray diffraction confirmed that the synthesized silver particles have a face centred cubic structure. EDS predicted the presence of elemental silver. The SEM images showed the synthesis of spherically mono-dispersed particles, with nano dimensions accounted by the TEM images. Infra-red spectrum adopted to the different organic functionalities present at the surface of the particles. TGA indicated an overall 11 % weight loss up to 1000 °C, suggesting desorption of biomolecules from the surface. X-ray photoelectron spectroscopy (XPS) analysis revealed the presence of metallic silver nanoparticles. The prepared material was utilized as catalyst in the oxidation of benzyl alcohol with molecular oxygen as the oxidant in methanol, under ambient conditions of temperature and pressure. Also Ag-NPs showed good to moderate anti-microbial activity employing the Agar disc diffusion method against various strains using Ciprofloxacin and Fluconazole as standard. Free radical scavenging activity of the nanoparticles were observed by modified 1,1-diphynyl-2-picrylhydrazyl, DPPH and 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), ABTS in vitro assays. The work presented here demonstrates the adaptability of the synthesized Ag-NPs in participating as a disinfectant agent, free radical scavenger and an effective oxidation catalyst. The basic premise of attaining sustainability through the green synthesis of smart multifaceted materials has been consciously addressed.

  13. Benzyl Alcohol Topical

    Science.gov (United States)

    Benzyl alcohol lotion is used to treat head lice (small insects that attach themselves to the skin) in adults ... children less than 6 months of age. Benzyl alcohol is in a class of medications called pediculicides. ...

  14. Radicals

    Czech Academy of Sciences Publication Activity Database

    Jahn, Ullrich; Cornils, B.

    Weinheim: Wiley-VCH, 2013 - (Cornils, B.; Herrmann, W.; Wong, C.; Zanthoff, H.), s. 1897-1898 ISBN 978-3-527-33307-3 Institutional support: RVO:61388963 Keywords : radicals * enzymatic catalysis * coenzyme B12 * ribonucleotide reductase * mutases Subject RIV: CC - Organic Chemistry

  15. Benzylation of Aromatic Compounds with Benzyl Chloride Catalyzed by Nafion/SiO2 Nanocomposite Catalyst

    Institute of Scientific and Technical Information of China (English)

    Kun Guo YANG; Rui Mao HUA; Hai WANG; Bo Qing XU1

    2005-01-01

    In the presence of Nafion/SiO2 nanocomposite catalyst, the benzylation of aromatic compounds with benzyl chloride proceeded to afford diphenylmethane derivatives in high yields.The catalyst showed high catalytic activity not only for electron-rich aromatic compounds, but also for electron-poor aromatic compounds. Under identical conditions, the self-benzylation of benzyl chloride, and dibenzylation and/or multi-benzylation of aromatic compounds were negligible.

  16. Radicals generated from 2-chloro-5-fluorotoluene by corona discharge

    Science.gov (United States)

    Yi, Eun Hye; Yoon, Young Wook; Lee, Sang Kuk

    2014-06-01

    The generation of molecular radicals in corona discharge was investigated spectroscopically by varying the experimental conditions applied to a substituted toluene precursor. Vibronic emission spectra were observed from the corona discharge of 2-chloro-5-fluorotoluene seeded in a large amount of carrier gas helium. From an analysis of emission spectra observed, it was confirmed that bond dissociation energy plays a key role in radical formation. The possible pathway for the formation of benzyl-type radicals is proposed to explain the observation.

  17. Synthesis and structures of scandium and lutetium benzyl complexes

    NARCIS (Netherlands)

    Meyer, N.; Roesky, Peter W.; Bambirra, Sergio; Meetsma, Auke; Hessen, Bart; Saliu, Kuburat; Takats, Josef

    2008-01-01

    Scandium and lutetium benzyl complexes were prepared. Reaction of [ScCl3(THF)(3)] with potassium benzyl afforded [Sc(CH2Ph)(3)(THF)(3)] (1). In the solid state the coordination polyhedron is a distorted octahedron, in which the benzyl groups are located in a facial arrangement on one side of the mol

  18. Preparation and study of dialkyl nitroxide radicals

    International Nuclear Information System (INIS)

    These radicals are obtained by oxidation of N-hydroxy-imides with lead tetracetate or p-nitro-perbenzoic acid. These imides are prepared by heating dicarboxylic acids anhydrides with benzyloxy-amine followed by catalytic hydrogenation of N-benzyloxy-imides so obtained. Two series of radicals have mainly been studied, the first concerning five-membered cyclic imides, the second six-membered cyclic imides, these molecules having methyls substituents or no on the carbon ring. N. M. R. spectra of some O-benzyl-imides have been analysed. These different results have made it possible to study the conformation and stereochemistry of these imides. (author)

  19. Conformational Studies on γ - Benzyl- L- Glutamate and L- Valine Containing Block Copolypeptides

    OpenAIRE

    Ajay Kumar

    2010-01-01

    Conformational studies on γ - benzyl-L- glutamate and L- valine containing block copolypeptides are reported using IR and CD spectra. The block copolypeptides contain valine block in the center and on both sides of the valine are γ - benzyl- L- glutamate blocks. The changes in conformation with increase in chain length of γ - benzyl- L- glutamate blocks are observed. When the chain length of γ - benzyl-L- glutamate block is 13, the block copolypeptide crystallized into beta conformation. With...

  20. Studies and characterization of in natura and benzylated sisal by using CPMAS 13C NMR

    International Nuclear Information System (INIS)

    Delignificated and benzylated sisal fibers were characterized by CPMAS 13 C NMR. In this study were analyzed the structure of the fiber before and after chemical treatments via delignification and benzylation processes. We observed that after delignification of sisal fiber, cellulose chains become more disordered and exposed which increases benzylation reaction efficiency. However, for not delignificated fibers their constituents decreases benzylation reaction efficiency. (author)

  1. Degradation kinetics of benzyl nicotinate in aqueous solution

    Directory of Open Access Journals (Sweden)

    Mbah C

    2010-01-01

    Full Text Available The degradation of benzyl nicotinate in aqueous solution over a pH range of 2.0-10.0 at 50±0.2 o was studied. The degradation was determined by high performance liquid chromatography. The degradation was observed to follow apparent first-order rate kinetics and the rate constant for the decomposition at 25 o was estimated by extrapolation. The reaction was shown to be hydroxide ion catalyzed and the Arrhenius plots showed the temperature dependence of benzyl nicotinate degradation. A significant increase in the stability of benzyl nicotinate was observed when glycerol or polyethylene glycol 400 was incorporated into the aqueous solution.

  2. Synthesis and structures of scandium and lutetium benzyl complexes

    OpenAIRE

    De Meyer, N.; Roesky, Peter W.; Bambirra, Sergio; Meetsma, Auke; Hessen, Bart; Saliu, Kuburat; Takats, Josef

    2008-01-01

    Scandium and lutetium benzyl complexes were prepared. Reaction of [ScCl3(THF)(3)] with potassium benzyl afforded [Sc(CH2Ph)(3)(THF)(3)] (1). In the solid state the coordination polyhedron is a distorted octahedron, in which the benzyl groups are located in a facial arrangement on one side of the molecule. One of the coordinated THF molecules could be removed by trituration with toluene and recrystallization of I from toluene to give [Sc(CH2Ph)(3)(THF)(2)] (2). A significantly different compou...

  3. Benzyl (E)-3-(4-meth­oxy­benzyl­idene)dithio­carbazate

    OpenAIRE

    Zheng Fan; Yan-Lan Huang; Zhao Wang; Han-Qi Guo; Shang Shan

    2011-01-01

    The title compound, C16H16N2OS2, was obtained from a condensation reaction of benzyl dithiocarbazate and 4-methoxybenzaldehyde. In the molecule, the methoxyphenyl ring and dithiocarbazate fragment are located on opposite sides of the C=N double bond, showing an E configuration. The dithiocarbazate fragment is approximately planar (r.m.s. deviation = 0.0052 Å); its mean plane is oriented at dihedral angles of 8.19 (15) and 85.70 (13)°, respective...

  4. Benzyl 3-[(E)-2-nitro­benzyl­idene]dithio­carbazate

    OpenAIRE

    Shang Shan; Yan-Lan Huang; Han-Qi Guo; Deng-Feng Li; Jian Sun

    2011-01-01

    The title compound, C15H13N3O2S2, was obtained from a condensation reaction of benzyl dithiocarbazate and 2-nitrobenzaldehyde. In the molecule, the nearly planar dithiocarbazate fragment [r.m.s deviation = 0.0264 Å] is oriented at dihedral angles of 7.25 (17) and 74.09 (9)°with respect to the two benzene rings. The nitro group is twisted by a dihedral angle of 22.4 (7)° to the attached benzene ring. The nitrobenzene ring and d...

  5. Benzyl (E)-3-(2-methyl­benzyl­idene)dithio­carbazate

    OpenAIRE

    Shang Shan; Zhao Wang; Yan-Lan Huang; Han-Qi Guo; Deng-Feng Li

    2011-01-01

    The title compound, C16H16N2S2, was obtained from the condensation reaction of benzyl dithiocarbazate and 2-methylbenzaldehyde. The asymmetric unit contains two independent molecules. In both molecules, the methylphenyl ring and the dithiocarbazate fragment are located on opposite sides of the C=N bond, showing an E conformation. In each molecule, the dithiocarbazate fragment is approximately planar, the r.m.s deviations being 0.018 and 0.025 Å. The mean plane of dithiocarb...

  6. Radical Evil

    Directory of Open Access Journals (Sweden)

    Carlos Manrique

    2007-12-01

    Full Text Available There is an aporia in Kant’s analysis of evil: he defines radical evilas an invisible disposition of the will, but he also demands an inferential connection between visible evil actions and this invisible disposition. This inference,however, undermines the radical invisibility of radical evil according to Kant’s own definition of the latter. Noting how this invisibility of moral worth is a distinctive feature of Kant’s approach to the moral problem, the paper then asks why, in the Groundwork, he nonetheless forecloses a question about evil that seems to be consistent with this approach. It is argued that to account for this aporia and this foreclosure, one has to interrogate the way in which the category of religion orients Kant’s incipient philosophy of history in Die Religion.

  7. Synthesis, antioxidant, enzyme inhibition and DNA binding studies of novel N-benzylated derivatives of sulfonamide

    Science.gov (United States)

    Abbas, Aadil; Murtaza, Shahzad; Tahir, Muhammad Nawaz; Shamim, Saima; Sirajuddin, Muhammad; Rana, Usman Ali; Naseem, Khadija; Rafique, Hummera

    2016-08-01

    A series of novel N-benzylated derivatives of sulfonamide were synthesized and characterized by FT-IR, NMR and XRD analysis. The synthesized compounds were assayed for their biological potential. The biological studies involved antioxidant, enzyme inhibition, and DNA interaction studies. Antioxidant potential was investigated by Ferric Reducing Antioxidant Power assay (FRAP) and DPPH free radical scavenging method, the capacity of synthesized compounds to inhibit the enzyme's activity was assayed by using the well-known Elman method whereas DNA interaction studies were carried out with the help UV-Vis absorption titration method. Moreover, a direct correlation between enzyme inhibition activity and concentration of the compounds was observed both in experimental and molecular docking studies. DNA interaction studies of the synthesized compounds showed weak interaction.

  8. Radical Geography

    Directory of Open Access Journals (Sweden)

    H. Hataminezhad

    2012-07-01

    Full Text Available Interdisciplinary sciences emerging and specialization were result of historical conditions. Lack of common and grand theories have caused social sciences such as Geography disintegrated to many courses. The Geography science has been divided two main courses, Physical and Human through the time. Every one used another similar science in theoretical principles and methodologies for their domain development and strengthening of their bases. The Human Geography was influenced by Anthropology during nineteenth century and was affected by nineteenth century and dawn twentieth century by Sociology and from mid twentieth century until present time by Biological sciences, Psychology, Political economics and social theories. Radical Geography was one of the Human Geography branches that was influenced by Political economics and left ideology. Radical Geography emphasizes on investigation about quality of life in different spaces and attempts to change socio-economic and spatial relationships, therefore critical Geography is one of its similar approaches.

  9. Growth and characterization of organic single crystal benzyl carbamate

    Science.gov (United States)

    Bala Solanki, S. Siva; Perumal, Rajesh Narayana; Suthan, T.; Bhagavannarayana, G.

    2015-10-01

    Benzyl carbamate single crystal is grown by a solution and vertical Bridgman technique for the first time. The cell parameters and morphologies are assessed from single crystal X-ray diffraction analysis. High resolution X-ray diffraction analysis indicates the crystalline perfection of the grown benzyl carbamate crystal. Fourier Transforms Infrared spectroscopy study has been applied to arrive at the different functional groups. Thermo gravimetric analysis and differential scanning calorimetry are used to study its thermal behavior. The microhardness test is carried out and the load dependent hardness is measured.

  10. A convenient procedure for the synthesis of allyl and benzyl ethers from alcohols and phenols

    Indian Academy of Sciences (India)

    H Surya Prakash Rao; S P Senthilkumar

    2001-06-01

    Allyl and benzyl ethers of alcohols can be prepared conveniently and in high yield with allyl and benzyl bromide in the presence of solid potassium hydroxide without use of any solvent. Phenols can be converted to allyl ethers but are inert to benzylation under above conditions.

  11. Roaming Radicals

    Science.gov (United States)

    Bowman, Joel M.; Shepler, Benjamin C.

    2011-05-01

    Roaming is a recently verified unusual pathway to molecular products from unimolecular dissociation of an energized molecule. Here we present the evidence for this pathway for H2CO and CH3CHO. Theoretical analysis shows that this path visits the plateau region of the potential energy surface near dissociation to radical products. It is not clear whether roaming is a distinct isolated pathway, in addition to the conventional one via the well-known molecular saddle-point transition state. Evidence is presented to suggest that the two pathways may originate from a single, but highly complicated, dividing surface. Other examples of unusual reaction dynamics are also reviewed.

  12. 3-Benzyl-6-benzyl­amino-1-methyl-5-nitro-1,2,3,4-tetra­hydro­pyrimidine

    OpenAIRE

    Surya Prakash Rao, H.; Sathishkumar, R.; Sarathbabu, M.; Manivel, P.; Kannan, M; Krishna, R.

    2010-01-01

    In the title compound, C19H22N4O2, the tetra­hydro­pyrimidine ring adopts an envelope conformation (with the N atom connected to the benzyl group representing the flap). This benzyl group occupies a quasi-axial position. The two benzyl groups lie over the tetra­hydro­pyridimidine ring. The amino group is a hydrogen-bond donor to the nitro group.

  13. Synthesis of allyloxy-ortho-iodobenzamide derivative from d-glucose and tri-n-butyltin hydride mediated radical cyclization reaction

    International Nuclear Information System (INIS)

    Methyl 6-O-allyl-2,3-di-O-benzyl-4-deoxy-4-(2 -iodobenzoylamine)-α-D-glucopyranoside was synthesized in nine conventional steps from methyl α-D-glucopyranoside. Its Bu3SnH-mediated aryl radical cyclization provided a benzomacrolactam, resulting from 11-endo aryl radical cyclization and the reduced uncyclized product methyl 6-O-allyl-4-benzoylamine-2,3-di-O-benzyl-4- deoxy- α-D-glucopyranoside. The structures of the three new products were supported by 1H and 13C NMR spectroscopy and DEPT, COSY and HMQC experiments. (author)

  14. European Union Summary Risk Assessment Report - Benzyl Butyl Phthalate (BBP)

    OpenAIRE

    PAKALIN Sazan; ASCHBERGER Karin; COSGROVE Orna; PAYA PEREZ Ana; VEGRO Stefania

    2008-01-01

    This report provides a summary, with conclusions, of the risk assessment report of the substance benzyl butyl phthalate (BBP) that has been prepared by Norway in the context of Council Regulation (EEC) No. 793/93 on the evaluation and control of existing substances. For detailed information on the risk assessment principles and procedures followed, the underlying data and the literature references the reader is referred to the comprehensive Final Risk Assessment Report (Final RAR) that ca...

  15. Green Synthesis of Benzylated Aromatics Using Iron Loaded Mesoporous Materials

    OpenAIRE

    Preethi, Muthuraj Esther Leena; Revathi, Shanmugam; Sivakumar, Thiripuranthagan

    2008-01-01

    Syntheses of benzylated aromatics like diphenylmethane and its derivatives by the condensation of benzene or toluene or o-xylene with benzylchloride or 4-methylbenzylchloride in the presence of a catalytic amount of various iron loaded mesoporous solid acid catalysts such as Fe/Al-MCM-41 (Si/Al=25), Fe/Al-MCM-41 (Si/Al=50) and Fe/Al-MCM-41 (Si/Al=100) are reported.

  16. Synthesis and Properties of Polyurethane Resins from Liquefied Benzylated Wood

    Institute of Scientific and Technical Information of China (English)

    Yu Ping WEI; Fa CHENG; Hou Ping LI; Jiu Gao YU

    2005-01-01

    In this paper, polyurethane resins were synthesized from liquefied benzylated wood and TDI (toluene diisocyanate)-TMP (trihydromethylene propane) prepolymer. And the relation between microphase structure and properties of PU samples were also studied. The results indicated that coatings obtained had good mechanical and thermal properties. The amount of the curing agent has great effect on the degree of phase segregation. In addition, with increased the curing agent amount, the thermal stabilities were also improved.

  17. Multichromic polymers of benzotriazole derivatives: Effect of benzyl substitution

    Energy Technology Data Exchange (ETDEWEB)

    Yigitsoy, Basak [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Abdul Karim, S.M. [Department of Arts and Sciences, Ahsanullah University of Science and Technology, Dhaka 1208 (Bangladesh); Balan, Abidin; Baran, Derya [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Toppare, Levent, E-mail: toppare@metu.edu.t [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Department of Biotechnology, Middle East Technical University, 06531 Ankara (Turkey); Department of Polymer Science and Technology, Middle East Technical University, 06531 Ankara (Turkey)

    2011-02-01

    Two electroactive monomers 1-benzyl-4,7-di(thiophen-2-yl))-2H-benzo[d][1,2,3]triazole (BBTA) and 2-benzyl-4,7-di(thiophen-2-yl))-2H-benzo[d][1,2,3]triazole (BBTS) were synthesized with satisfactory yields. The effect of substitution site on electrochemical and optical properties was investigated with cyclic voltammetry and spectroelectrochemical studies. Results showed that position of pendant group alters the electronic structure of the resulting polymer causing different optical and electrochemical behaviors. Symmetrically positioned benzyl unit on benzotriazole moiety resulted in a neutral state red polymer, PBBTS, having multi-colored property in its different oxidized and reduced states. Its analogue PBBTA exhibited maximum absorption at 390 nm in its neutral state and also revealed multicolored electrochromic property upon stepwise oxidation. Very different optical band gap values were calculated: 1.55 eV and 2.25 eV for PBBTS and PBBTA, respectively.

  18. Multichromic polymers of benzotriazole derivatives: Effect of benzyl substitution

    International Nuclear Information System (INIS)

    Two electroactive monomers 1-benzyl-4,7-di(thiophen-2-yl))-2H-benzo[d][1,2,3]triazole (BBTA) and 2-benzyl-4,7-di(thiophen-2-yl))-2H-benzo[d][1,2,3]triazole (BBTS) were synthesized with satisfactory yields. The effect of substitution site on electrochemical and optical properties was investigated with cyclic voltammetry and spectroelectrochemical studies. Results showed that position of pendant group alters the electronic structure of the resulting polymer causing different optical and electrochemical behaviors. Symmetrically positioned benzyl unit on benzotriazole moiety resulted in a neutral state red polymer, PBBTS, having multi-colored property in its different oxidized and reduced states. Its analogue PBBTA exhibited maximum absorption at 390 nm in its neutral state and also revealed multicolored electrochromic property upon stepwise oxidation. Very different optical band gap values were calculated: 1.55 eV and 2.25 eV for PBBTS and PBBTA, respectively.

  19. Synthesis of Pharmaceutical Intermediates by Toluene Benzylation over Heteropoly Acids on Different Support

    Institute of Scientific and Technical Information of China (English)

    V. V. Bokade; G.D. Yadav

    2007-01-01

    Selective formation of pharmaceutical intermediates like diphenylmethane, dimethyldiphenylmethane, benzyl toluene and benzoic acid by liquid phase, toluene benzylation with benzyl chloride as a benzylating agent, was systematically studied over plane clay (K-10, montmorillonite),plane H-Beta, plane MFI structured titanosilicate (TS-1) and heteropoly acids [HPA, namely dodecasupported on clay, H-beta and TS-1. The 20%TPA/Clay, 30%TPA/H-Beta and 30%TPA/TS-1, were observed to be the best catalyst samples over plane clay, plane H-Beta and plane TS-1. The catalyst samples are compared with respect to benzyl chloride conversion and selectivities for diphenylmethane,dimethyl-diphenylmethane, benzyl toluene and benzoic acid. The reaction follows the pseudo-first order rate power law model. The apparent rate constants are calculated and compared with the reported ones.

  20. In situ spectroscopic investigation of oxidative dehydrogenation and disproportionation of benzyl alcohol

    OpenAIRE

    Nowicka, E.; HOFMANN, J.P.; Parker, S. F.; Sankar, M.; Lari, G.M.; Kondrat, S.A.; Knight, D. W.; Bethell, D; Weckhuysen, B.M.; G. J. Hutchings

    2013-01-01

    In the solvent free oxidation of benzyl alcohol, using supported gold–palladium nanoalloys, toluene is often one of major by-products and it is formed by the disproportionation of benzyl alcohol. Gold–palladium catalysts on acidic supports promote both the disproportionation of benzyl alcohol and oxidative dehydrogenation to form benzaldehyde. Basic supports completely switch off disproportionation and the gold–palladium nanoparticles catalyse the oxidative dehydrogenation reaction exclusivel...

  1. Anaphylaxis Triggered by Benzyl Benzoate in a Preparation of Depot Testosterone Undecanoate

    OpenAIRE

    Ong, Gregory S. Y.; Somerville, Colin P.; Jones, Timothy W; Walsh, John P.

    2012-01-01

    We report the first case of an anaphylactic reaction to Reandron 1000 (depot testosterone undecanoate with a castor oil and benzyl benzoate vehicle). While considered to have a favourable safety profile, serious complications such as oil embolism and anaphylaxis can occur. In our patient, skin testing identified benzyl benzoate to be the trigger, with no reaction to castor oil or testosterone undecanoate components. As benzyl benzoate exists in multiple pharmaceuticals, foods, and cosmetics, ...

  2. 3-Benzyl-6-benzylamino-1-methyl-5-nitro-1,2,3,4-tetrahydropyrimidine

    Directory of Open Access Journals (Sweden)

    H. Surya Prakash Rao

    2010-03-01

    Full Text Available In the title compound, C19H22N4O2, the tetrahydropyrimidine ring adopts an envelope conformation (with the N atom connected to the benzyl group representing the flap. This benzyl group occupies a quasi-axial position. The two benzyl groups lie over the tetrahydropyridimidine ring. The amino group is a hydrogen-bond donor to the nitro group.

  3. Photocatalytic benzylic C–H bond oxidation with a flavin scandium complex

    OpenAIRE

    Mühldorf, Bernd; Wolf, Robert

    2015-01-01

    The enhanced reduction potential of riboflavin tetraacetate coordinating to scandium triflate enables the challenging photocatalytic C–H oxidation of electron-deficient alkylbenzenes and benzyl alcohols.

  4. Benzyl 3-[(E)-1-(pyrazin-2-yl)ethylidene]dithiocarbazate

    OpenAIRE

    Shang Shan; Yan-Lan Huang; Han-Qi Guo; Deng-Feng Li; Jian Sun

    2011-01-01

    The title compound, C14H14N4S2, was obtained from a condensation reaction of benzyl dithiocarbazate and acetylpyrazine. The asymmetric unit contains two independent molecules, in each of which the pyrazine ring and dithiocarbazate unit are approximately co-planar, the r.m.s. deviations being 0.0304 and 0.0418 Å. The mean plane is oriented with respect to the benzene ring at 49.22 (4)° in one molecule and at 69.76 (7)° in the other. In t...

  5. Benzylation of arenes and heteroarenes catalyzed by HfCl4/HfO2

    Institute of Scientific and Technical Information of China (English)

    Cheng Yi Zhang; Xin Qin Gao; Jiang Hua Zhang; Xiao Jun Peng

    2009-01-01

    A highly efficient benzylation of arenes and heteroarenes catalyzed by HfC14/HfO2 has been developed. Broad scope of benzylation reagents have been used in this process with high yields under mild condition. Additionally, the HfO2 can be re-used after the reaction.

  6. Benzyl (E)-3-(2-bromo-5-meth­oxy­benzyl­idene)dithio­carbazate

    OpenAIRE

    Zheng Fan; Yan-Lan Huang; Zhao Wang; Han-Qi Guo; Shang Shan

    2011-01-01

    The title compound, C16H15BrN2OS2, was obtained from the condensation reaction of benzyl dithiocarbazate and 2-bromo-5-methoxylbenzaldehyde. In the molecule, the bromomethoxyphenyl ring and dithiocarbazate fragment are located on the opposite sides of the C=N double bond, showing the E conformation. The dithiocarbazate fragment is approximately planar (r.m.s deviation 0.0187 Å); its mean plane is oriented with respect to the bromomethoxyphenyl and phenyl rings at 7.60&#...

  7. Depolymerization of lignin by microwave-assisted methylation of benzylic alcohols.

    Science.gov (United States)

    Zhu, Guodian; Qiu, Xueqing; Zhao, Ying; Qian, Yong; Pang, Yuxia; Ouyang, Xinping

    2016-10-01

    A new two-step lignin depolymerization strategy was developed, in which the benzylic alcohols in lignin was methylated under microwave irradiation, followed by a hydrogenolysis for the cleavage of βO4 bond with Pd/C as the catalyst. The results showed that an efficient and selective catalytic methylation of benzylic alcohols was achieved with various lignin model compounds, and the acidic environment promoted the methylation of benzylic alcohol. Methylation of benzylic alcohol increased the βO4 bond cleavage rate by 55.9%, and improved products selectivity. Preliminary study of lignin depolymerization illustrated that methylation pretreatment of benzylic alcohols facilitated lignin depolymerization to produce aromatic monomers and reduced the oxygen content of aromatic monomers. PMID:27420159

  8. A new approach to synthesis of benzyl cinnamate: Optimization by response surface methodology.

    Science.gov (United States)

    Zhang, Dong-Hao; Zhang, Jiang-Yan; Che, Wen-Cai; Wang, Yun

    2016-09-01

    In this work, the new approach to synthesis of benzyl cinnamate by enzymatic esterification of cinnamic acid with benzyl alcohol is optimized by response surface methodology. The effects of various reaction conditions, including temperature, enzyme loading, substrate molar ratio of benzyl alcohol to cinnamic acid, and reaction time, are investigated. A 5-level-4-factor central composite design is employed to search for the optimal yield of benzyl cinnamate. A quadratic polynomial regression model is used to analyze the experimental data at a 95% confidence level (Ptrials are performed for validating the optimum points. Under the optimum conditions (40°C, 31mg/mL enzyme loading, 2.6:1 molar ratio, 27h), the yield reaches 97.7%, which provides an efficient processes for industrial production of benzyl cinnamate. PMID:27041296

  9. Palladium-catalyzed thiocarbonylation of aryl, vinyl, and benzyl bromides.

    Science.gov (United States)

    Burhardt, Mia N; Ahlburg, Andreas; Skrydstrup, Troels

    2014-12-19

    A catalytic protocol for synthesis of thioesters from aryl, vinyl, and benzyl bromides as well as benzyl chlorides was developed using only stoichiometric amounts of carbon monoxide, produced from a solid CO precursor inside a two-chamber system. As a catalytic system, the combination of bis(benzonitrile) palladium(II) chloride and Xantphos furnished the highest yields of the desired compounds, along with the weak base, NaOAc, in anisole at 120 °C. The choice of catalytic system as well as solvent turned out to be important in order to ensure a high chemoselectivity in the reaction. Both electron-rich and electron-deficient aryl bromides worked well in this reaction. Addition of 1 equiv of sodium iodide to the reaction improved the chemoselectivity with the electron-deficient aryl bromides. The thiol scope included both aryl and alkyl thiols, including 2-mercaptobenzophenones, whereby a thiocarbonylation followed by a subsequent McMurry coupling yielded differently substituted benzothiophenes. It was demonstrated that the methodology could be applied for (13)C introduction into the thiophene ring. PMID:24919457

  10. Infrared spectroscopy of organic free radicals related to combustion processes

    Energy Technology Data Exchange (ETDEWEB)

    Weisshaar, J.C. [Univ. of Wisconsin, Madison (United States)

    1993-12-01

    The primary long-term goal of this work is to develop new techniques for measuring vibrational spectra of polyatomic neutral free radicals. The authors explore a variation of resonant two-photon ionization (R2PI) in which tunable {omega}{sub IR} excites the radical vibrationally and {omega}{sub UV} selectively ionizes only the vibrationally excited molecules. Development of the IR + UV R2PI experiment is underway. In the meantime, the authors have used optical R2PI and pulsed field ionization (PFI) detection to obtain new vibrational spectra of species such as the benzyl and phenylsilane cations. In benzyl, a great deal was learned about the vibronic coupling mechanism in the mixed q{sup 2}A{sub 2}-2{sup 2}B{sub 2} system near 450 nm by projecting the mixed states onto the manifold of cation vibrational states. In phenylsilane{sup +}, we find that the sixfold barrier to internal rotation of the silyl group is small (V{sub 6} = +19 cm{sup {minus}1}). We are beginning to understand the mechanisms of coupling of torsional states with vibration, overall rotation, and other electronic states. In addition, we are developing a new model of internal rotation in aromatic compounds based on Prof. Frank Weinhold`s natural resonance theory.

  11. Synthesis and Anti-HIV-1 Activity of New MKC-442 Analogues with an Alkynyl-Substituted 6-Benzyl Group

    DEFF Research Database (Denmark)

    Aly, Youssef L.; Pedersen, Erik Bjerreg.; La Colla, Paolo;

    2007-01-01

    Synthesis and antiviral activities are reported of a series of 6-(3-alkynyl benzyl)-substituted analogues of MKC-442 (6-benzyl-1-(ethoxymethyl)-5-isopropyluracil), a highly potent agent against HIV. The 3-alkynyl group is assumed to give a better stacking of the substituted benzyl group to revers...

  12. Antimicrobial, antioxidant, cytotoxic and molecular docking properties of N-benzyl-2,2,2-trifluoroacetamide

    Science.gov (United States)

    Balachandran, C.; Kumar, P. Saravana; Arun, Y.; Duraipandiyan, V.; Sundaram, R. Lakshmi; Vijayakumar, A.; Balakrishna, K.; Ignacimuthu, S.; Al-Dhabi, N. A.; Perumal, P. T.

    2015-02-01

    N-Benzyl-2,2,2-trifluoroacetamide was obtained by acylation of benzylamine with trifluoroacetic anhydride using Friedel-Crafts acylation method. The synthesised compound was confirmed by spectroscopic and crystallographic techniques. N-Benzyl-2,2,2 -trifluoroacetamide was assessed for its antimicrobial, antioxidant, cytotoxic and molecular docking properties. It showed good antifungal activity against tested fungi and moderate antibacterial activity. The minimum inhibitory concentration values of N-benzyl-2,2,2 -trifluoroacetamide against fungi were 15.62 μg/mL against A. flavus, 31.25 μg/mL against B. Cinerea and 62.5 μg/mL against T. mentagrophytes, Scopulariopsis sp., C. albicans and M. pachydermatis. N-Benzyl-2,2,2-trifluoroacetamide showed 78.97 ± 2.24 of antioxidant activity at 1,000 μg/mL. Cupric ion reducing antioxidant capacity of N-benzyl-2,2,2-trifluoroacetamide was dependent on the concentration. Ferric reducing antioxidant power assay of N-benzyl-2,2,2-trifluoroacetamide showed (1.352 ± 0.04 mM Fe(II)/g) twofold higher value compared to the standard. N-Benzyl-2,2,2-trifluoroacetamide showed 75.3 % cytotoxic activity at the dose of 200 μg/mL with IC50 (54.7 %) value of 100 μg/mL. N-Benzyl-2,2,2-trifluoroacetamide was subjected to molecular docking studies for the inhibition AmpC beta-lactamase, Glucosamine-6-Phosphate Synthase and lanosterol 14 alpha-demethylase (CYP51) enzymes which are targets for antibacterial and antifungal drugs. Docking studies of N-benzyl-2,2,2-trifluoroacetamide showed low docking energy. N-Benzyl-2,2,2-trifluoroacetamide can be evaluated further for drug development.

  13. Radical prostatectomy - discharge

    Science.gov (United States)

    ... prostatectomy - discharge; Laparoscopic radical prostatectomy - discharge; LRP - discharge; Robotic-assisted laparoscopic prostatectomy - discharge ; RALP - discharge; Pelvic lymphadenectomy - ...

  14. Free radical inactivation of trypsin

    International Nuclear Information System (INIS)

    Reactivities of free radical oxidants, radical OH, Br2-anion radical and Cl3COO radical and a reductant, CO2-anion radical, with trypsin and reactive protein components were determined by pulse radiolysis of aqueous solutions at pH 7, 200C. Highly reactive free radicals, radical OH, Br2-anion radical and CO2-anion radical, react with trypsin at diffusion controlled rates. Moderately reactive trichloroperoxy radical, k(Cl3COO radical + trypsin) preferentially oxidizes histidine residues. The efficiency of inactivation of trypsin by free radicals is inversely proportional to their reactivity. The yields of inactivation of trypsin by radical OH, Br2-anion radical and CO2-anion radical are low, G(inactivation) = 0.6-0.8, which corresponds to ∼ 10% of the initially produced radicals. In contrast, Cl3COO radical inactivates trypsin with ∼ 50% efficiency, i.e. G(inactivation) = 3.2. (author)

  15. Rate constants for the reactions of free radicals with oxygen in solution

    International Nuclear Information System (INIS)

    The kinetics of the rections of several free radicals with oxygen have been examined in solution at 300 K using laser flash photolysis techniques. The reactions of resonance-stabilized radicals are only slightly slower than those of nonstabilized radicals: for example, for tert-butyl (in cyclohexane), 4.93 x 109; benzyl, 2.36 x 109 (in cyclohexane); cyclohexadienyl (in benzene), 1.64 x 109 M-1 s-1. The reaction of butyl-tin (n-Bu3Sn.) radicals is unusually fast (7.5 x 109 M-1 s-1), a fact that has been tentatively attributed to a relaxation of spin selection rules due to heavy atom effects. 1 table

  16. Radical theory of rings

    CERN Document Server

    Gardner, JW

    2003-01-01

    Radical Theory of Rings distills the most noteworthy present-day theoretical topics, gives a unified account of the classical structure theorems for rings, and deepens understanding of key aspects of ring theory via ring and radical constructions. Assimilating radical theory's evolution in the decades since the last major work on rings and radicals was published, the authors deal with some distinctive features of the radical theory of nonassociative rings, associative rings with involution, and near-rings. Written in clear algebraic terms by globally acknowledged authorities, the presentation

  17. Solvent effects in the reaction between piperazine and benzyl bromide

    Indian Academy of Sciences (India)

    S Ranga Reddy; P Manikyamba

    2007-11-01

    The reaction between piperazine and benzyl bromide was studied conductometrically and the second order rate constants were computed. These rate constants determined in 12 different protic and aprotic solvents indicate that the rate of the reaction is influenced by electrophilicity (), hydrogen bond donor ability () and dipolarity/polarizability (*) of the solvent. The LSER derived from the statistical analysis indicates that the transition state is more solvated than the reactants due to hydrogen bond donation and polarizability of the solvent while the reactant is more solvated than the transition state due to electrophilicity of the solvent. Study of the reaction in methanol, dimethyl formamide mixtures suggests that the rate is maximum when dipolar interactions between the two solvents are maximum.

  18. Structure and dynamics at the liquid surface of benzyl alcohol

    Energy Technology Data Exchange (ETDEWEB)

    Dietter, J.; Morgner, H. [Institut fuer Experimentalphysik, Naturwissenschaftliche Fakultaet, Universitaet Witten/Herdecke, Stockumerstrasse 10, D-58453 Witten-Annen (Germany)

    1999-02-01

    A molecular dynamics simulation of a liquid layer of benzyl alcohol has been performed in order to compare the results with those obtained in experimental studies of our group. The main result of the experimental work was a strong orientational ordering of the benzyl alcohol molecules in the surface as well as an exceptionally large surface potential of ca. 0.6 V. According to the experiments the surface molecules orientate in such a way that the benzene ring points toward the vapor phase while the CH{sub 2} group and the OH group are directed towards the bulk of the liquid. The simulation confirms this orientation of the surface molecules. The surface potential resulting from the simulation is 350 mV. The simulation reveals that the rather large surface potential can be understood as a consequence of the mean orientation of the molecular dipole moment in the surface region. The mean orientation of the molecules themselves in the surface is due to the tendency of the system to maintain the hydrogen bonding structure of the bulk in the surface region as well. The preferential orientation of the surface molecules causes a change of the dynamics of the individual components of the molecules when switching from bulk to surface which depends on the separation of these components from the polar group. This becomes most obvious in case of the reorientation dynamics of the molecular axes, e.g. the reorientation of the benzene ring is faster than the reorientation of the OH group. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  19. Anaphylaxis Triggered by Benzyl Benzoate in a Preparation of Depot Testosterone Undecanoate

    Directory of Open Access Journals (Sweden)

    Gregory S. Y. Ong

    2012-01-01

    Full Text Available We report the first case of an anaphylactic reaction to Reandron 1000 (depot testosterone undecanoate with a castor oil and benzyl benzoate vehicle. While considered to have a favourable safety profile, serious complications such as oil embolism and anaphylaxis can occur. In our patient, skin testing identified benzyl benzoate to be the trigger, with no reaction to castor oil or testosterone undecanoate components. As benzyl benzoate exists in multiple pharmaceuticals, foods, and cosmetics, individual components of pharmaceuticals should be tested when investigating drug allergies. Doctors should be alert to the potential for serious reactions to any of the components of Reandron 1000.

  20. The retro Grignard addition reaction revisited: the reversible addition of benzyl reagents to ketones

    DEFF Research Database (Denmark)

    Christensen, Stig Holden; Holm, Torkil; Madsen, Robert

    2014-01-01

    The Grignard addition reaction is known to be a reversible process with allylic reagents, but so far the reversibility has not been demonstrated with other alkylmagnesium halides. By using crossover experiments it has been established that the benzyl addition reaction is also a reversible...... transformation. The retro benzyl reaction was shown by the addition of benzylmagnesium chloride to di-tert-butyl ketone followed by exchange of both the benzyl and the ketone moiety with another substrate. Similar experiments were performed with phenylmagnesium bromide and tert-butylmagnesium chloride, but in...... these two cases the Grignard addition reaction did not show any sign of a reverse transformation....

  1. Selective methylation of kaempferol via benzylation and deacetylation of kaempferol acetates.

    Science.gov (United States)

    Mei, Qinggang; Wang, Chun; Yuan, Weicheng; Zhang, Guolin

    2015-01-01

    A strategy for selective mono-, di- and tri-O-methylation of kaempferol, predominantly on the basis of selective benzylation and controllable deacetylation of kaempferol acetates, was developed. From the selective deacetylation and benzylation of kaempferol tetraacetate (1), 3,4',5,-tri-O-acetylkaempferol (2) and 7-O-benzyl-3,4'5,-tri-O-acetylkaempferol (8) were obtained, respectively. By controllable deacetylation and followed selective or direct methylation of these two intermediates, eight O-methylated kaempferols were prepared with 51-77% total yields from kaempferol. PMID:25815082

  2. Laparoscopic radical cystectomy

    OpenAIRE

    Fergany, Amr

    2012-01-01

    Objective Laparoscopic radical cystectomy (LRC) has emerged as a minimally invasive alternative to open radical cystectomy (ORC). This review focuses on patient selection criteria, technical aspects and postoperative outcomes of LRC. Methods Material for the review was obtained by a PubMed search over the last 10 years, using the keywords ‘laparoscopic radical cystectomy’ and ‘laparoscopic bladder cancer’ in human subjects. Results Twenty-two publications selected for relevance and content we...

  3. Laparoscopic Radical Trachelectomy

    OpenAIRE

    Rendón, Gabriel J.; Ramirez, Pedro T.; Frumovitz, Michael; Schmeler, Kathleen M.; Pareja, Rene

    2012-01-01

    Introduction: The standard treatment for patients with early-stage cervical cancer has been radical hysterectomy. However, for women interested in future fertility, radical trachelectomy is now considered a safe and feasible option. The use of minimally invasive surgical techniques to perform this procedure has recently been reported. Case Description: We report the first case of a laparoscopic radical trachelectomy performed in a developing country. The patient is a nulligravid, 30-y-old fem...

  4. Reaction of selected carbohydrate aldehydes with benzylmagnesium halides: benzyl versus o-tolyl rearrangement

    Directory of Open Access Journals (Sweden)

    Maroš Bella

    2014-08-01

    Full Text Available The Grignard reaction of 2,3-O-isopropylidene-α-D-lyxo-pentodialdo-1,4-furanoside and benzylmagnesium chloride (or bromide afforded a non-separable mixture of diastereomeric benzyl carbinols and diastereomeric o-tolyl carbinols. The latter resulted from an unexpected benzyl to o-tolyl rearrangement. The proportion of benzyl versus o-tolyl derivatives depended on the reaction conditions. Benzylmagnesium chloride afforded predominantly o-tolyl carbinols while the application of benzylmagnesium bromide led preferably to the o-tolyl carbinols only when used in excess or at higher temperatures. The structures of the benzyl and o-tolyl derivatives were confirmed unambiguously by NMR spectral data and X-ray crystallographic analysis of their 5-ketone analogues obtained by oxidation of the corresponding mixture of diastereomeric carbinols. A possible mechanism for the Grignard reaction leading to the benzyl→o-tolyl rearrangement is also proposed.

  5. Palladium-catalyzed Cascade Cyclization-Coupling Reaction of Benzyl Halides with N,N-Diallylbenzoylamide

    Institute of Scientific and Technical Information of China (English)

    Yi Min HU; Yu ZHANG; Jian Lin HAN; Cheng Jian ZHU; Yi PAN

    2003-01-01

    A novel type of palladium-catalyzed cascade cyclization-coupling reaction has been found. Reaction of N, N-diallylbenzoylamide 1 with benzyl halides 2 afforded the corresponding dihydropyrroles 3 in moderate to excellent yields.

  6. Polystyrene-supported Benzyl Selenide: An Efficient Reagent for Highly Stereocontrolled Synthesis of Substituted Olefins

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Polystyrene-supported benzyl selenide has been prepared. This novel reagent was treated with LDA to produce a selenium stabilized carbanion, which reacted with alkyl halide, followed by selenoxide syn-elimination, to give substituted olefins stereospecificly.

  7. Photocatalytic benzylic C-H bond oxidation with a flavin scandium complex.

    Science.gov (United States)

    Mühldorf, Bernd; Wolf, Robert

    2015-05-18

    The enhanced reduction potential of riboflavin tetraacetate coordinating to scandium triflate enables the challenging photocatalytic C-H oxidation of electron-deficient alkylbenzenes and benzyl alcohols. PMID:25647055

  8. Kinetic Studies on the Selective Oxidation of Benzyl Alcohols in Organic Medium under Phase Transfer Catalysis

    Directory of Open Access Journals (Sweden)

    K. Bijudas

    2014-07-01

    Full Text Available Kinetic studies on the oxidation of benzyl alcohol and substituted benzyl alcohols in benzene as the reaction medium have been studied by using potassium dichromate under phase transfer catalysis (PTC. The phase transfer catalysts (PT catalysts used were tetrabutylammonium bromide (TBAB and tetrabutylphosphonium bromide (TBPB.  Benzyl alcohols were selectively oxidised to corresponding benzaldehydes in good yield (above 90%.  The order of reactivity among the studied benzyl alcohols is p - OCH3 > p - CH3 > - H > p - Cl.  Plots of log k2 versus Hammett's substituent constant (s has been found to be curve shaped and this suggests that there should be a continuous change in transition state with changes in substituent present in the substrate from electron donating to electron withdrawing. A suitable mechanism has been suggested in which the rate determining step involves both C - H bond cleavage and C - O bond formations in concerted manner. © 2014 BCREC UNDIP. All rights reserved.Received: 16th March 2014; Revised: 18th May 2014; Accepted: 18th May 2014[How to Cite: Bijudas, K., Bashpa, P., Nair, T.D.R. (2014. Kinetic Studies on the Selective Oxidation of Benzyl Alcohol and Substituted Benzyl Alcohols in Organic Medium under Phase Transfer Catalysis. Bulletin of Chemical Reaction Engineering & Catalysis, 9 (2: 142-147. (doi:10.9767/bcrec.9.2.6476.142-147][Permalink/DOI: http://dx.doi.org/10.9767/bcrec.9.2.6476.142-147] 

  9. Physiology of free radicals

    Directory of Open Access Journals (Sweden)

    Stevanović Jelka

    2011-01-01

    Full Text Available Free radicals imply that every atom, molecule, ion, group of atoms, or molecules with one or several non-paired electrons in outer orbital. Among these are: nitrogenoxide (NO•, superoxide-anion-radical (O2•-, hydroxyl radical (OH•, peroxyl radical (ROO•, alcoxyl radical (RO• and hydroperoxyl radical (HO2•. However, reactive oxygen species also include components without non-paired electrons in outer orbital (so-called reactive non-radical agents, such as: singlet oxygen (1O2, peroxynitrite (ONOO-, hydrogen-peroxide (H2O2, hypochloric acid (eg. HOCl and ozone (O3. High concentrations of free radicals lead to the development of oxidative stress which is a precondition for numerous pathological effects. However, low and moderate concentrations of these matter, which occur quite normally during cell metabolic activity, play multiple significant roles in many reactions. Some of these are: regulation of signal pathways within the cell and between cells, the role of chemoattractors and leukocyte activators, the role in phagocytosis, participation in maintaining, changes in the position and shape of the cell, assisting the cell during adaption and recovery from damage (e.g.caused by physical effort, the role in normal cell growth, programmed cell death (apoptosis and cell ageing, in the synthesis of essential biological compounds and energy production, as well as the contribution to the regulation of the vascular tone, actually, tissue vascularization.

  10. Dietary Exposure to Benzyl Butyl Phthalate in China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lei; JIANG Ding Guo; SUI Hai Xia; WU Ping Gu; LIU Ai Dong; YANG Da Jin; LIU Zhao Ping; SONG Yan; LI Ning

    2016-01-01

    ObjectiveBenzyl butyl phthalate (BBP) is a plasticizer used in food contact materials. Dietary exposure to BBP might lead to reproduction and developmental damages to human. The present paper was aimed to assess the health risk of BBP dietary exposure in Chinese population. MethodsThe BBP contents were detected in 7409 food samples from 25 foodcategories by gas chromatography-mass spectrometry operated in selected ion monitoring (SIM) mode. The dietary exposures of BBP in different age and sex groups were estimated by combining the content data with food consumption data derived from 2002 China National Nutrient and Health Survey, and evaluated according to the tolerable daily intake (TDI) of BBP established by European Food safety Agency. ResultsIt was found that BBP was undetectable in most samples and the highest level was 1.69 mg/kg detected in a vegetable oil sample. The average dietary exposure of BBP in people aged≥2 years was 1.03 μg/kgbw perday and the highest average exposure was found in 2-6 years old children (1.98 μg/kg bw perday). The BBP exposure in 7-12 months old children excessed 10% of tolerable daily intake (TDI) in worst scenario. ConclusionThe health risk of BBP dietary exposure in Chinese population is low and, considering BBP alone, there is no safety concern.

  11. 3 Benzyl-6-chloropyrone: a suicide inhibitor of cholesterol esterase

    International Nuclear Information System (INIS)

    Cholesterol, absorbed from the intestine, appears in lymph as the ester. Cholesterol esterase is essential for this process, since depletion of the enzyme blocks and repletion restores, absorption. Selective inhibitors of cholesterol esterase may thus prove useful in reducing cholesterol uptake. A series of potential suicide substrates were synthesized which, following cleavage by the enzyme, would attack the putative nucleophile in the active site. One of these, 3-benzyl-6-chloropyrone (3BCP), inhibited both synthesis and hydrolysis of 14C-cholesteryl oleate with an I50 of approximately 150 μM. The inactivation was time-dependent and characteristic of a suicide mechanism. The α pyrone structure (lactone analog) is cleaved by a serine-hydroxyl in the active site. This generates an enoyl chloride which inactivates the imidazole believed to play a part in the catalytic function of the enzyme. Inhibition by 3BCP is selective for cholesterol esterase. The activity of pancreatic lipase as not affected by concentrations up to 1 mM

  12. Benzyl alcohol increases voluntary ethanol drinking in rats.

    Science.gov (United States)

    Etelälahti, T J; Eriksson, C J P

    2014-09-01

    The anabolic steroid nandrolone decanoate has been reported to increase voluntary ethanol intake in Wistar rats. In recent experiments we received opposite results, with decreased voluntary ethanol intake in both high drinking AA and low drinking Wistar rats after nandrolone treatment. The difference between the two studies was that we used pure nandrolone decanoate in oil, whereas in the previous study the nandrolone product Deca-Durabolin containing benzyl alcohol (BA) was used. The aims of the present study were to clarify whether the BA treatment could promote ethanol drinking and to assess the role of the hypothalamic-pituitary-adrenal-gonadal axes (HPAGA) in the potential BA effect. Male AA and Wistar rats received subcutaneously BA or vehicle oil for 14 days. Hereafter followed a 1-week washout and consecutively a 3-week voluntary alcohol consumption period. The median (± median absolute deviation) voluntary ethanol consumption during the drinking period was higher in BA-treated than in control rats (4.94 ± 1.31 g/kg/day vs. 4.17 ± 0.31 g/kg/day, p = 0.07 and 1.01 ± 0.26 g/kg/day vs. 0.38 ± 0.27 g/kg/day, p = 0.05, for AA and Wistar rats, respectively; combined effect p Deca-Durabolin containing BA need to be re-evaluated. PMID:24871566

  13. Selective cytotoxicity of benzyl isothiocyanate in the proliferating fibroblastoid cells.

    Science.gov (United States)

    Miyoshi, Noriyuki; Uchida, Koji; Osawa, Toshihiko; Nakamura, Yoshimasa

    2007-02-01

    In the present study, experiments using presynchronization culture cells demonstrated that benzyl ITC (BITC), previously isolated from a tropical papaya fruit extract, induced the cytotoxic effect preferentially in the proliferating human colon CCD-18Co cells to the quiescent ones. Quiescent CCD-18Co cells were virtually unaffected by BITC and marginal cytotoxicity was observed at 15 microM. We observed that BITC dramatically induced the p53 phosphorylation and stabilization only in the quiescent (G(0)/G(1) phase-arrested) cells, but not significantly in the proliferating human colon CCD-18Co cells when compared with quiescent ones. We also observed ataxia telangiectasia-mutated (ATM) phosphorylation in the quiescent cells. The BITC-induced p53 phosphorylation was counteracted by caffeine treatment, implying the involvement of an ATM/ataxia telangiectasia and Rad3-related kinase signaling pathway. Moreover, downregulation of p53 by a siRNA resulted in the enhancement of susceptibility to undergo apoptosis by BITC. We also showed here that depletion of p53 abrogated G(0)/G(1) arrest accompanied by the declined expression of p21(waf1/cip1) and p27(kip1) in CCD-18Co cells. In conclusion, we identified p53 as a potential negative regulator of the apoptosis induction by BITC in the normal colon CCD-18Co cells through the inhibition of cell-cycle progression at the G(0)/G(1) phase. PMID:17096346

  14. Toxicity of benzyl alcohol in adult and neonatal mice

    International Nuclear Information System (INIS)

    Benzyl alcohol (BA) is an aromatic alcohol, which is used as a bacteriostat in a variety of parenteral preparations. In 1982, it was implicated as the agent responsible for precipitating The Gasping Syndrome in premature neonates. The investigate further this toxicity, BA was administered, intraperiotoneally, to adult and neonatal CD-1 male mice. Gross behavioral changes were monitored. Low doses produced minimal toxic effects within an initial 4 hour observation period. At the end of this time, the LD50 was determined to be 1000 mg/kg for both age groups. Death was due to respiratory arrest in all cases. Rapid absorption and conversion of BA to its primary metabolite, benzaldehyde, was demonstrated by gas chromatographic analysis of plasma from both experimental groups. The conversion of BA to benzaldehyde was confirmed in in vitro by using both horse-liver and mouse liver ADH. The inhibition of alcohol dehydrogenase (ADH) by pyrazole was similarly demonstrated in both enzyme systems. 14C-labelled BA was utilized to determine the distribution of BA and its metabolites in the body, and to possibly pinpoint a target organ of toxicity

  15. A novel and selective oxidation of benzylic alcohols with polymer-supported periodic acid under mild aprotic conditions

    Institute of Scientific and Technical Information of China (English)

    Ali Reza Pourali; Mehrosadat Tabaean; S. Mohamad Reza Nazifi

    2012-01-01

    A new polymeric oxidizing reagent was prepared by supporting periodic acid on poly(1,4-phenylene-2,5-pyridine dicarboxyamide).This polymeric reagent was used for the selective oxidation of primary benzylic alcohols to the corresponding benzaldehydes in CH3CN at reflux conditions.Excellent selectivity was observed between primary benzyl alcohols and secondary ones as well as non-benzylic alcohols in the oxidation reactions.Allylic alcohols were also converted to the corresponding aldehydes with good yields.

  16. Benzyl acetates as attractants for the male oriental fruit fly, Dacus dorsalis, and the male melon fly, Dacus cucurbitae

    OpenAIRE

    Metcalf, Robert L.; Metcalf, Esther R.; Mitchell, W. C.

    1986-01-01

    Fifty compounds related to benzyl acetate were evaluated quantitatively as attractants to the male oriental fruit fly (Dacus dorsalis) and the male melon fly (Dacus cucurbitae). Thienylmethyl acetate was nearly as attractive as benzyl acetate to both species, but cyclohexylmethyl acetate was completely unattractive, emphasizing the role of the planar aromatic ring in receptor interaction. Although benzyl acetate was equally attractive to both species, para substituents invariably reduced attr...

  17. Co(III)-Carbene Radical Approach to Substituted 1H-Indenes.

    Science.gov (United States)

    Das, Braja Gopal; Chirila, Andrei; Tromp, Moniek; Reek, Joost N H; Bruin, Bas de

    2016-07-20

    A new strategy for the catalytic synthesis of substituted 1H-indenes via metalloradical activation of o-cinnamyl N-tosyl hydrazones is presented, taking advantage of the intrinsic reactivity of a Co(III) carbene radical intermediate. The reaction uses readily available starting materials and is operationally simple, thus representing a practical method for the construction of functionalized 1H-indene derivatives. The cheap and easy to prepare low spin cobalt(II) complex [Co(II)(MeTAA)] (MeTAA = tetramethyltetraaza[14]annulene) proved to be the most active catalyst among those investigated, which demonstrates catalytic carbene radical reactivity for a nonporphyrin cobalt(II) complex, and for the first time catalytic activity of [Co(II)(MeTAA)] in general. The methodology has been successfully applied to a broad range of substrates, producing 1H-indenes in good to excellent yields. The metallo-radical catalyzed indene synthesis in this paper represents a unique example of a net (formal) intramolecular carbene insertion reaction into a vinylic C(sp(2))-H bond, made possible by a controlled radical ring-closure process of the carbene radical intermediate involved. The mechanism was investigated computationally, and the results were confirmed by a series of supporting experimental reactions. Density functional theory calculations reveal a stepwise process involving activation of the diazo compound leading to formation of a Co(III)-carbene radical, followed by radical ring-closure to produce an indanyl/benzyl radical intermediate. Subsequent indene product elimination involving a 1,2-hydrogen transfer step regenerates the catalyst. Trapping experiments using 2,2,6,6-tetra-methylpiperidine-1-oxyl (TEMPO) radical or dibenzoylperoxide (DBPO) confirm the involvement of cobalt(III) carbene radical intermediates. Electron paramagnetic resonance spectroscopic spin-trapping experiments using phenyl N-tert-butylnitrone (PBN) reveal the radical nature of the reaction. PMID

  18. Radical chemistry of artemisinin

    Energy Technology Data Exchange (ETDEWEB)

    Denisov, Evgenii T; Solodova, S L; Denisova, Taisa G [Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka, Moscow Region (Russian Federation)

    2010-12-29

    The review summarizes physicochemical characteristics of the natural sesquiterpene peroxide artemisinin. The kinetic schemes of transformations of artemisinin radicals under anaerobic conditions are presented and analyzed. The sequence of radical reactions of artemisinin in the presence of oxygen is considered in detail. Special emphasis is given to the intramolecular chain oxidation resulting in the transformation of artemisinin into polyatomic hydroperoxide. The kinetic characteristics of elementary reaction steps involving alkyl, alkoxyl, and peroxyl radicals generated from artemisinin are discussed. The results of testing of artemisinin and its derivatives for the antimalarial activity and the scheme of the biochemical synthesis of artemisinin in nature are considered.

  19. Solubilities of benzoic acid in binary (benzyl alcohol + benzaldehyde) solvent mixtures

    International Nuclear Information System (INIS)

    Highlights: • Solubilities of benzoic acid in (benzyl alcohol + benzaldehyde) mixtures were measured at 1 atm. • The experimental temperature ranges at (298.35 to 355.65) K. • Effects of benzyl alcohol mass concentration at (0.00 to 1.00) on the solubilities of benzoic acid were studied. • The experimental data were correlated with NRTL model. • Thermodynamic functions of dissolution of benzoic acid in (benzyl alcohol + benzaldehyde) mixtures were discussed. - Abstract: The solubility of benzoic acid in binary (benzyl alcohol + benzaldehyde) solvent mixtures was measured at temperature from (298.35 to 355.65) K and atmospheric pressure. The measured solubility increases with the increasing temperature at constant solvent composition. The effects of mass fraction benzaldehyde in the solvent mixtures at (0.0 to 1.00) on the solubility were studied. The measured solubility decreases with the increasing mass fraction of benzaldehyde. The experimental results were correlated with the non-random two-liquid (NRTL) equations, and good agreement between the correlated and the experimental values was obtained. Thermodynamic functions for the solution of benzoic acid in binary (benzyl alcohol + benzaldehyde) solvent mixtures were calculated with the van’t Hoff plot. The apparent dissolution Gibbs free energy change was also calculated

  20. Radical cystectomy in eldery

    OpenAIRE

    Bančević Vladimir; Aleksić Predrag; Milović Novak; Spasić Aleksandar; Kovačević Božidar; Toševski Perica; Čampara Zoran; Milošević Radovan; Cerović Snežana

    2015-01-01

    Background/Aim. Radical cystectomy is the method of choice for the treatment of muscle invasive bladder cancer. This major surgery is associated with many complications, especially in older patients. The aim of this study was to analyze preoperative comorbidity, and intraoperative and postoperative complicatons in patients older than 75 years. Methods. This clinical, retrospective study included 46 patients over 75 years, who underwent radical cystectomy. I...

  1. Controlled Radical Polymerisation of Styrene in the Presence of Lithium Molybdate(V) Complexes and Benzylic Halides

    NARCIS (Netherlands)

    Koten, G. van; Brandts, J.A.M.; Geijn, P. van de; Faassen, E.E.H. van; Boersma, J.

    1999-01-01

    The new lithium molybdate(V) complexes [LiMo(NAr){2}(C-N)R] (C-N=C{6}H{4}(CH{2}NMe{2})-2; R=(C-N) (5), Me (6), CH{2}SiMe{3} (7), p-tolyl (8)), have been generated in situ from reaction of the corresponding molybdenum(VI) complexes [Mo(NAr){2}(C-N)R] (C-N=C{6}H{4}(CH{2}NMe{2})-2; R=(C-N) (1), Me (2),

  2. Synthesis, Anticancer and Antibacterial Activity of Salinomycin N-Benzyl Amides

    Directory of Open Access Journals (Sweden)

    Michał Antoszczak

    2014-11-01

    Full Text Available A series of 12 novel monosubstituted N-benzyl amides of salinomycin (SAL was synthesized for the first time and characterized by NMR and FT-IR spectroscopic methods. Molecular structures of three salinomycin derivatives in the solid state were determined using single crystal X-ray method. All compounds obtained were screened for their antiproliferative activity against various human cancer cell lines as well as against the most problematic bacteria strains such as methicillin-resistant Staphylococcus aureus (MRSA and Staphylococcus epidermidis (MRSE, and Mycobacterium tuberculosis. Novel salinomycin derivatives exhibited potent anticancer activity against drug-resistant cell lines. Additionally, two N-benzyl amides of salinomycin revealed interesting antibacterial activity. The most active were N-benzyl amides of SAL substituted at -ortho position and the least anticancer active derivatives were those substituted at the -para position.

  3. Reactivity of H. formed in the radiolysis of benzyl alcohol containing tetracycline hydrochloride at 77 K+

    International Nuclear Information System (INIS)

    The radiolysis of tetracycline hydrochloride dissolved in benzyl alcohol was studied at 77 K by ESR. The H. and e- which are formed in the radiolysis of benzyl alcohol at 77 K migrate over a distance corresponding to about 95 and 995 molecules of solvent, respectively, before they are captured by the tetracycline hydrochloride solute. The migration of H. in neopentane matrix is more favoured than in benzyl alcohol matrix. When the mole ratio between solute and solvent is 1:10000, the reactivity of H. observed by ESR is the following: a) 20% of H. reacts preferentially with solute; b) 80% of H. reacts exclusively with the solvent in the first collision. (author)

  4. Free Radical Reactions in Food.

    Science.gov (United States)

    Taub, Irwin A.

    1984-01-01

    Discusses reactions of free radicals that determine the chemistry of many fresh, processed, and stored foods. Focuses on reactions involving ascorbic acid, myoglobin, and palmitate radicals as representative radicals derived from a vitamin, metallo-protein, and saturated lipid. Basic concepts related to free radical structure, formation, and…

  5. Modeling of the Reaction Mechanism of Enzymatic Radical C-C Coupling by Benzylsuccinate Synthase.

    Science.gov (United States)

    Szaleniec, Maciej; Heider, Johann

    2016-01-01

    Molecular modeling techniques and density functional theory calculations were performed to study the mechanism of enzymatic radical C-C coupling catalyzed by benzylsuccinate synthase (BSS). BSS has been identified as a glycyl radical enzyme that catalyzes the enantiospecific fumarate addition to toluene initiating its anaerobic metabolism in the denitrifying bacterium Thauera aromatica, and this reaction represents the general mechanism of toluene degradation in all known anaerobic degraders. In this work docking calculations, classical molecular dynamics (MD) simulations, and DFT+D2 cluster modeling was employed to address the following questions: (i) What mechanistic details of the BSS reaction yield the most probable molecular model? (ii) What is the molecular basis of enantiospecificity of BSS? (iii) Is the proposed mechanism consistent with experimental observations, such as an inversion of the stereochemistry of the benzylic protons, syn addition of toluene to fumarate, exclusive production of (R)-benzylsuccinate as a product and a kinetic isotope effect (KIE) ranging between 2 and 4? The quantum mechanics (QM) modeling confirms that the previously proposed hypothetical mechanism is the most probable among several variants considered, although C-H activation and not C-C coupling turns out to be the rate limiting step. The enantiospecificity of the enzyme seems to be enforced by a thermodynamic preference for binding of fumarate in the pro(R) orientation and reverse preference of benzyl radical attack on fumarate in pro(S) pathway which results with prohibitively high energy barrier of the radical quenching. Finally, the proposed mechanism agrees with most of the experimental observations, although the calculated intrinsic KIE from the model (6.5) is still higher than the experimentally observed values (4.0) which suggests that both C-H activation and radical quenching may jointly be involved in the kinetic control of the reaction. PMID:27070573

  6. Modeling of the Reaction Mechanism of Enzymatic Radical C–C Coupling by Benzylsuccinate Synthase

    Science.gov (United States)

    Szaleniec, Maciej; Heider, Johann

    2016-01-01

    Molecular modeling techniques and density functional theory calculations were performed to study the mechanism of enzymatic radical C–C coupling catalyzed by benzylsuccinate synthase (BSS). BSS has been identified as a glycyl radical enzyme that catalyzes the enantiospecific fumarate addition to toluene initiating its anaerobic metabolism in the denitrifying bacterium Thauera aromatica, and this reaction represents the general mechanism of toluene degradation in all known anaerobic degraders. In this work docking calculations, classical molecular dynamics (MD) simulations, and DFT+D2 cluster modeling was employed to address the following questions: (i) What mechanistic details of the BSS reaction yield the most probable molecular model? (ii) What is the molecular basis of enantiospecificity of BSS? (iii) Is the proposed mechanism consistent with experimental observations, such as an inversion of the stereochemistry of the benzylic protons, syn addition of toluene to fumarate, exclusive production of (R)-benzylsuccinate as a product and a kinetic isotope effect (KIE) ranging between 2 and 4? The quantum mechanics (QM) modeling confirms that the previously proposed hypothetical mechanism is the most probable among several variants considered, although C–H activation and not C–C coupling turns out to be the rate limiting step. The enantiospecificity of the enzyme seems to be enforced by a thermodynamic preference for binding of fumarate in the pro(R) orientation and reverse preference of benzyl radical attack on fumarate in pro(S) pathway which results with prohibitively high energy barrier of the radical quenching. Finally, the proposed mechanism agrees with most of the experimental observations, although the calculated intrinsic KIE from the model (6.5) is still higher than the experimentally observed values (4.0) which suggests that both C–H activation and radical quenching may jointly be involved in the kinetic control of the reaction. PMID:27070573

  7. “On water” sp3–sp2 cross-couplings between benzylic and alkenyl halides†

    OpenAIRE

    Krasovskaya, Valeria; Krasovskiy, Arkady; Bhattacharjya, Anish; Lipshutz, Bruce H.

    2011-01-01

    Organic-solvent-free cross-couplings between benzylic and alkenyl halides have been developed. Various alkenyl halides can be effciently benzylated by combining the precursor halides in the presence of Zn dust and a Pd catalyst at room temperature, in water as the only medium.

  8. Intra- and Intermolecular Nickel-Catalyzed Reductive Cross-Electrophile Coupling Reactions of Benzylic Esters with Aryl Halides.

    Science.gov (United States)

    Konev, Mikhail O; Hanna, Luke E; Jarvo, Elizabeth R

    2016-06-01

    Nickel-catalyzed cross-electrophile coupling reactions of benzylic esters and aryl halides have been developed. Both inter- and intramolecular variants proceed under mild reaction conditions. A range of heterocycles and functional groups are tolerated under the reaction conditions. Additionally, the first example of a stereospecific cross-electrophile coupling of a secondary benzylic ester is described. PMID:27099968

  9. 1,3 Dipolar Cycloaddition Reactions of Substituted Benzyl Azides eith Tans-Dibenzoylethlene : Thermally Stable Trizoles Versus Unstable Triazolines

    International Nuclear Information System (INIS)

    Benzyl and Several Substituted benzyl azides Ιa-q reacted with trans -dibenzoylethylene 2 to give the thermaly unstable trizolinrs 3 which lose nitrogen molecule to yield either enamines 4 or enolimines 5. (Author's) 13 refs., 2 tabs., 4 strus., 1 sche., 2 figs

  10. Efficient oxidation of benzyl alcohol with heteropolytungstate as reaction-controlled phase-transfer catalyst

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A series of heteropolytungstates has been synthesized and utilized as catalysts to catalyze oxidation of benzyl alcohol with aqueous hydrogen peroxide. The results indicated that three of these catalysts showed the properties of reaction-controlled phasetransfer catalysis, and they had excellent catalytic ability to the oxidation of benzyl alcohol. No other by-products were detected by gas chromatography. Once the hydrogen peroxide was consumed completely, the catalyst precipitated from solvent, and the results of the catalyst recycle showed that the catalyst had high stability.

  11. Base metal-catalyzed benzylic oxidation of (aryl)(heteroaryl)methanes with molecular oxygen

    Science.gov (United States)

    Sterckx, Hans; De Houwer, Johan; Mensch, Carl; Herrebout, Wouter; Tehrani, Kourosch Abbaspour

    2016-01-01

    Summary The methylene group of various substituted 2- and 4-benzylpyridines, benzyldiazines and benzyl(iso)quinolines was successfully oxidized to the corresponding benzylic ketones using a copper or iron catalyst and molecular oxygen as the stoichiometric oxidant. Application of the protocol in API synthesis is exemplified by the alternative synthesis of a precursor to the antimalarial drug Mefloquine. The oxidation method can also be used to prepare metabolites of APIs which is illustrated for the natural product papaverine. ICP–MS analysis of the purified reaction products revealed that the base metal impurity was well below the regulatory limit. PMID:26877817

  12. Gangs, Terrorism, and Radicalization

    Directory of Open Access Journals (Sweden)

    Scott Decker

    2011-01-01

    Full Text Available What can street gangs tell us about radicalization and extremist groups? At first glance, these two groups seem to push the boundaries of comparison. In this article, we examine the important similarities and differences across criminal, deviant, and extremist groups. Drawing from research on street gangs, this article explores issues such as levels of explanation,organizational structure, group process, and the increasingly important role of technology and the Internet in the context of radicalization. There are points of convergence across these groups, but it is important to understand the differences between these groups. This review finds little evidence to support the contention that American street gangs are becoming increasingly radicalized. This conclusion is based largely on organizational differences between gangs and terror groups.

  13. Sexuality Following Radical Prostatectomy

    DEFF Research Database (Denmark)

    Fode, Mikkel; Serefoglu, Ege C; Albersen, Maarten;

    2016-01-01

    INTRODUCTION: Radical prostatectomies can result in urinary incontinence and sexual dysfunction. Traditionally, these issues have been studied separately, and the sexual problem that has received the most focus has been erectile dysfunction. AIM: To summarize the literature on sexually related side...... effects and their consequences after radical prostatectomy and focus on the occurrence and management of problems beyond erectile dysfunction. METHODS: The literature on sexuality after radical prostatectomy was reviewed through a Medline search. Original research using quantitative and qualitative...... methodologies was considered. Priority was given to studies exploring aspects of sexuality other than erectile function. MAIN OUTCOME MEASURES: The prevalence, predictive factors, and management of post-prostatectomy sexual problems beyond erectile dysfunction. RESULTS: Most patients will develop urinary...

  14. Homegrown religious radicalization

    DEFF Research Database (Denmark)

    Khawaja, Iram

    and their families. Existing literature and ways of thinking about the social psychological process of radicalization will be reviewed, such as social identity theory and transformative learning theory, and a theoretical framework based on a focus on belonging, recognition and the sense of community......It has been reported that a growing number of youngsters from Western Europe are engaging in conflicts motivated by religious and political conflicts in the Middle East. This paper aims at exploring the reasons behind this seemingly religious radicalization from the point of view of the youngsters...

  15. tri-n-butyltin hydride-mediated radical reaction of a 2-iodobenzamide: formation of an unexpected carbon-tin bond

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Marcelo T.; Alves, Rosemeire B.; Cesar, Amary [Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil). Dept. de Quimica; Prado, Maria Auxiliadora F.; Alves, Ricardo J.; Queiroga, Carla G. [Federal de Minas Gerais, Belo Horizonte, MG (Brazil). Faculdade de Farmacia. Dept. de Produtos Farmaceuticos]. E-mail: pradora@farmacia.ufmg.br; Santos, Leonardo S. [Universidad de Talca (Chile). Inst. de Quimica de Recursos Naturales; Eberlin, Marcos N. [Universidade Estadual de Campinas, SP (Brazil). Inst. de Quimica

    2007-03-15

    The tri-n-butyltin hydride-mediated reaction of methyl 2,3-di-O-benzyl-4-O-trans-cinnamyl- 6-deoxy-6-(2-iodobenzoylamino)-{alpha}-D-galactopyranoside afforded an unexpected aryltributyltin compound. The structure of this new tetraorganotin(IV) product has been elucidated by {sup 1}H, {sup 13}C NMR spectroscopy, COSY and HMQC experiments and electrospray ionization mass spectrometry (ESI-MS). The formation of this new compound via a radical coupling reaction and a radical addition-elimination process is discussed. (author)

  16. Violent Radicalization in Europe

    DEFF Research Database (Denmark)

    Dalgaard-Nielsen, Anja

    2010-01-01

    When, why, and how do people living in a democracy become radicalized to the point of being willing to use or directly support the use of terrorist violence against fellow citizens? This question has been at the center of academic and public debate over the past years as terrorist attacks...

  17. Radical School Reform.

    Science.gov (United States)

    Gross, Beatrice, Ed.; Gross, Ronald, Ed.

    This book provides a comprehensive examination of the nature of the school crisis and the ways in which radical thinkers and educators are dealing with it. Excerpts from the writings of Jonathan Kozol, John Holt, Kenneth Clark, and others are concerned with the realities of education in ghettos and suburbs. Paul Goodman, Marshall McLuhan, Sylvia…

  18. Radically enhanced molecular recognition

    KAUST Repository

    Trabolsi, Ali

    2009-12-17

    The tendency for viologen radical cations to dimerize has been harnessed to establish a recognition motif based on their ability to form extremely strong inclusion complexes with cyclobis(paraquat-p-phenylene) in its diradical dicationic redox state. This previously unreported complex involving three bipyridinium cation radicals increases the versatility of host-guest chemistry, extending its practice beyond the traditional reliance on neutral and charged guests and hosts. In particular, transporting the concept of radical dimerization into the field of mechanically interlocked molecules introduces a higher level of control within molecular switches and machines. Herein, we report that bistable and tristable [2]rotaxanes can be switched by altering electrochemical potentials. In a tristable [2]rotaxane composed of a cyclobis(paraquat-p-phenylene) ring and a dumbbell with tetrathiafulvalene, dioxynaphthalene and bipyridinium recognition sites, the position of the ring can be switched. On oxidation, it moves from the tetrathiafulvalene to the dioxynaphthalene, and on reduction, to the bipyridinium radical cation, provided the ring is also reduced simultaneously to the diradical dication. © 2010 Macmillan Publishers Limited. All rights reserved.

  19. On Radical Feminism

    Institute of Scientific and Technical Information of China (English)

    翟良锴

    2015-01-01

    <正>All men are created equal.For centuries,human have been struggling for their rights.Women,as a special social force,are fighting vigorously for their equal rights with men.According to an introduction to feminism,there are three main types of feminism:socialist,reformist and radical(Feminism 101).In order

  20. Radical Financial Innovation

    OpenAIRE

    Robert J. Shiller

    2004-01-01

    Radical financial innovation is the development of new institutions and methods that permit risk management to be extended far beyond its former realm, covering important new classes of risks. This paper compares past such innovation with potential future innovation, looking at the process that produced past success and the possibilities for future financial innovation.

  1. Allylic and benzylic sp3 C-H oxidation in water.

    Science.gov (United States)

    Ang, Wei Jie; Lam, Yulin

    2015-01-28

    A copper-catalyzed method for the oxidation of allylic and benzylic sp(3) C-H by aqueous tert-butyl hydroperoxide (T-Hydro) in water using a recyclable fluorous ligand has been developed. The reaction procedure is tolerant to additional functional groups and the fluorous ligand could be reused with little loss of catalytic activity. PMID:25412371

  2. A Case of Abnormal Bishler-Napieralski Cyclization Reaction, Leading to Form Benzyl Oxazole Derivatives

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A benzyl oxazole compound 3 was obtained with an excellent yield of 90% when N-acetyl-(2?methoxy-4?5?methylenedioxy)-phenylalanine methyl ester 1 was refluxed in POCl3 /benzene. However, the anticipated product 3,4-dihydroisoquinoline-3-carboxylic acid methyl ester 2 could not be found. The mechanism was discussed in this article.

  3. "Decarbonization" of an imino N-heterocyclic carbene via triple benzyl migration from hafnium

    Science.gov (United States)

    An imino N-heterocyclic carbene underwent three sequential benzyl migrations upon reaction with tetrabenzylhafnium, resulting in complete removal of the carbene carbon from the ligand. The resulting eneamido-amidinato hafnium complex showed alkene polymerization activity comparable to that of a prec...

  4. Design, synthesis and biological activity of novel peptidyl benzyl ketone FVIIa inhibitors

    DEFF Research Database (Denmark)

    Storgaard, Morten; Henriksen, Signe Teuber; Zaragoza, Florencio;

    2011-01-01

    Herein is described the synthesis of a novel class of peptidyl FVIIa inhibitors having a C-terminal benzyl ketone group. This class is designed to be potentially suitable as stabilization agents of liquid formulations of rFVIIa, which is a serine protease used for the treatment of hemophilia A an...

  5. 1 H and 13 C NMR studies on the enoling of 5-benzyl barbituric acids

    International Nuclear Information System (INIS)

    This work shows that the derivatives of the 5-benzyl barbituric acids hydroxylated at the ortho position of the aromatic ring only exist in the enol form. and that the alkylation of this hydroxyl gives products which exist mainly in the ketone form of the DMSO

  6. Homocoupling of benzyl halides catalyzed by POCOP-nickel pincer complexes

    KAUST Repository

    Chen, Tao

    2012-08-01

    Two types of POCOP-nickel(II) pincer complexes were prepared by mixing POCOP pincer ligands and NiX 2 in toluene at reflux. The resulting nickel complexes efficiently catalyze the homocoupling reactions of benzyl halides in the presence of zinc. The coupled products were obtained in excellent to quantitative yields. © 2012 Elsevier Ltd. All rights reserved.

  7. Non-heme iron catalysts for the benzylic oxidation : a parallel ligand screening approach

    NARCIS (Netherlands)

    Klopstra, M; Hage, R; Kellogg, R.M.; Feringa, B.L.

    2003-01-01

    Ethylbenzene and 4-ethylanisole were used as model substrates for benzylic oxidation with H2O2 or O-2 using a range of non-heme iron catalysts following a parallel ligand screening approach. Effective oxidation was found for Fe complexes based on tetra- and pentadentate nitrogen ligands affording th

  8. OH radicals in the troposphere

    International Nuclear Information System (INIS)

    OH radicals are radicals which determine the photochemistry of the troposphere. The reactivity of OH radicals to organic substances is one of the fundamental criteria for the evaluation of abiotic decomposition. Details are given about the photochemical formation and reaction of OH radicals, the decomposition reactions of organic compounds in the gaseous phase, the determination of the specific rates of OH radical decomposition reactions, measuring methods for the determination of OH radical concentrations in the troposphere, selected results, OH concentration distributions obtained from model calculations, and the influence of trace gases on OH concentrations. A summary, conclusions, and research proposals are attached. (orig./BBR)

  9. Unusual C-C bond cleavage in the formation of amine-bis(phenoxy) group 4 benzyl complexes: Mechanism of formation and application to stereospecific polymerization

    KAUST Repository

    Gowda, Ravikumar R.

    2014-08-11

    Group 4 tetrabenzyl compounds MBn4 (M = Zr, Ti), upon protonolysis with an equimolar amount of the tetradentate amine-tris(phenol) ligand N[(2,4-tBu2C6H2(CH 2)OH]3 in toluene from -30 to 25 °C, unexpectedly lead to amine-bis(phenoxy) dibenzyl complexes, BnCH2N[(2,4- tBu2C6H2(CH2)O] 2MBn2 (M = Zr (1), Ti (2)) in 80% (1) and 75% (2) yields. This reaction involves an apparent cleavage of the >NCH2-ArOH bond (loss of the phenol in the ligand) and formation of the >NCH 2-CH2Bn bond (gain of the benzyl group in the ligand). Structural characterization of 1 by X-ray diffraction analysis confirms that the complex formed is a bis(benzyl) complex of Zr coordinated by a newly derived tridentate amine-bis(phenoxy) ligand arranged in a mer configuration in the solid state. The abstractive activation of 1 and 2 with B(C6F 5)3·THF in CD2Cl2 at room temperature generates the corresponding benzyl cations {BnCH2N[(2,4- tBu2C6H2(CH2)O] 2MBn(THF)}+[BnB(C6F5) 3]- (M = Zr (3), Ti, (4)). These cationic complexes, along with their analogues derived from (imino)phenoxy tri- and dibenzyl complexes, [(2,6-iPr2C6H3)N=C(3,5- tBu2C6H2)O]ZrBn3 (5) and [2,4-Br2C6H2(O)(6-CH2(NC 5H9))CH2N=CH(2-adamantyl-4-MeC 6H2O)]ZrBn2 (6), have been found to effectively polymerize the biomass-derived renewable β-methyl-α-methylene- γ-butyrolactone (βMMBL) at room temperature into the highly stereoregular polymer PβMMBL with an isotacticity up to 99% mm. A combined experimental and DFT study has yielded a mechanistic pathway for the observed unusual C-C bond cleavage in the present protonolysis reaction between ZrBn4 and N[(2,4-tBu2C 6H2(CH2)OH]3 for the formation of complex 1, which involves the benzyl radical and the Zr(III) species, resulting from thermal and photochemical decomposition of ZrBn4, followed by a series of reaction sequences consisting of protonolysis, tautomerization, H-transfer, oxidation, elimination, and radical coupling. © 2014 American Chemical Society.

  10. Free radical transfer in polymers

    International Nuclear Information System (INIS)

    For the present study of free-radical transfer in polymers pulse radiolysis and product studies have been carried out in aqueous solutions using thus far only the water-soluble polymers polyacrylic acid, polymethacrylic acid and polyvinyl alcohol. When OH radicals, generated in the radiolysis of N2O-saturated aqueous solutions, react with polymers the lifetime of the polymer radical thus created very much depends on the number of radicals per polymer chain. When there are a large number of radicals per chain their bimolecular decay may be faster than the corresponding (diffusion controlled) decay of monomeric radicals, but when the macromolecule contains only few or even just one radical their lifetime is considerably prolonged. Highly charged polymers such as polyacrylic acid at high pH attain a rod-like conformation which again favors a long lifetime of the radicals. Under such conditions, radical transfer reactions can occur. For example, in polyacrylic acid OH radicals generate two kinds of radicals side by side. The radical in β-position to the carboxylate group converts into the thermodynamically more stable α-radicals by an H-transfer reaction as can be followed by spectrophotometry. Besides radical transfer reactions β-fragmentation reactions occur causing chain scission. Such reactions can be followed in a pulse radiolysis experiment by conductometry, because counter ions are released upon chain scission. Such a process is especially effective in the case of polymethacrylic acid, where it results in a chain depolymerization. An intramolecular H-abstraction is also observed in the γ-radiolysis of polyacrylic acid with the corresponding peroxyl radicals. This causes a chain reaction to occur. The resulting hydroperoxides are unstable and decarboxylate given rise to acetylacetone-like products. In polyvinyl alcohol the peroxyl radicals in α-position to the alcohol function undergo HO2-elimination. This prevents a scission of the polymer chain in the

  11. Investigation of comparative efficacy of eugenol and benzyl benzoate in therapy of sheep mange

    Directory of Open Access Journals (Sweden)

    Jezdimirović Milanka

    2010-01-01

    Full Text Available The acaricide efficacy, tolerance and safety of eugenol (10 and 20 % in the treatment of sarcoptic mange in sheep have been investigated. The results were compared with those corresponding for benzyl benzoate (25 %, which was applied to sheep in the same way. The treatment was applied on sheep three times in one-week intervals. Skin scrapings were sampled seven days after each treatment, as well as twenty-eight days following the third one. The changes on the skin were quantified and the mean recovery response (MRR was calculated. The clinical efficacy was assessed according to the MRR and the number of mites in the samples. Following the first treatment 10%eugenol was not significantly less efficacious in comparison with the higher concentration. Having been applied twice 20% eugenol was significantly more efficacious when compared to the lower concentration, which remained the same seven and twenty-eight days after the third application. The efficacy of 10% eugenol in the therapy of mange was significantly higher in comparison with benzyl benzoate following one, two or three administrations. The efficacy of benzyl benzoate four weeks after the third treatment was still significantly lower in comparison with 10% eugenol. The efficacy of 20% eugenol was significantly higher in comparison with its lower concentration as well as that of benzyl benzoate, following the second, and seven and twenty-eight days after the third one. No signs of local or systemic intolerance were observed in sheep treated with either 10 or 20% eugenol, or 25 % benzyl benzoate. .

  12. Toward Radicalizing Community Service Learning

    Science.gov (United States)

    Sheffield, Eric C.

    2015-01-01

    This article advocates a radicalized theoretical construction of community service learning. To accomplish this radicalization, I initially take up a discussion of traditional understandings of CSL rooted in pragmatic/progressive thought. I then suggest that this traditional structural foundation can be radicalized by incorporating Deborah…

  13. Oligorotaxane Radicals under Orders

    OpenAIRE

    WANG, YUPING; Frasconi, Marco; Liu, Wei-Guang; Sun, Junling; Wu, Yilei; Nassar, Majed S.; Botros, Youssry Y.; Goddard, William A.; Wasielewski, Michael R.; Stoddart, J. Fraser

    2016-01-01

    A strategy for creating foldameric oligorotaxanes composed of only positively charged components is reported. Threadlike components—namely oligoviologens—in which different numbers of 4,4′-bipyridinium (BIPY2+) subunits are linked by p-xylylene bridges, are shown to be capable of being threaded by cyclobis(paraquat-p-phenylene) (CBPQT4+) rings following the introduction of radical-pairing interactions under reducing conditions. UV/vis/NIR spectroscopic and electrochemical investigations sugge...

  14. Oligorotaxane Radicals under Orders

    OpenAIRE

    WANG, YUPING; Frasconi, Marco; Liu, Wei-Guang; Sun, Junling; Wu, Yilei; Nassar, Majed S.; Botros, Youssry Y.; Goddard, William A.; Wasielewski, Michael R.; Stoddart, J. Fraser

    2016-01-01

    A strategy for creating foldameric oligorotaxanes composed of only positively charged components is reported. Threadlike components—namely oligoviologens—in which different numbers of 4,4′-bipyridinium (BIPY^(2+)) subunits are linked by p-xylylene bridges, are shown to be capable of being threaded by cyclobis(paraquat-p-phenylene) (CBPQT^(4+)) rings following the introduction of radical-pairing interactions under reducing conditions. UV/vis/NIR spectroscopic and electrochemical investigations...

  15. Highly active and reusable catalyst from Fe-Mg-hydrotalcite anionic clay for Friedel-Crafts type benzylation reactions

    Indian Academy of Sciences (India)

    Vasant R Choudhary; Rani Jha; Pankaj A Choudhari

    2005-11-01

    Fe-Mg-hydrotalcite (Mg/Fe = 3) anionic clay with or without calcination (at 200-800°C) has been used for the benzylation of toluene and other aromatic compounds by benzyl chloride. Hydrotalcite before and after its calcination was characterized for surface area, crystalline phases and basicity. Both the hydrotalcite, particularly after its use in the benzylation reaction, and the catalyst derived from it by its calcination at 200-800°C show high catalytic activity for the benzylation of toluene and other aromatic compounds. The catalytically active species present in the catalyst in its most active form are the chlorides and oxides of iron on the catalyst surface.

  16. Electrocatalytic activity of surface adsorbed ruthenium-alizarin complexone toward the oxidation of benzyl alcohol

    International Nuclear Information System (INIS)

    The surface electrochemical behavior of an adsorbed alizarin complexone (abbreviated as AC) and its surface coordination with Ru(II) were studied in aqueous solution at a pH range of 0-6. The surface complex of ruthenium with AC displays strong electrocatalytic activities toward benzyl alcohol. Based on the rotating disk electrode measurement, it is believed that the electrocatalytic oxidation of benzyl alcohol is a two-electron and two-proton process with benzaldehyde as a major product. On the other hand, ruthenium-AC surface complex has also shown catalytic activities toward electro-oxidation of several small organic molecules such as methanol, formic acid, formaldehyde, ethanol, and acetaldehyde

  17. Crystal structures of HIV-1 nonnucleoside reverse transcriptase inhibitors: N-benzyl-4-methyl-benzimidazoles

    Science.gov (United States)

    Ziółkowska, Natasza E.; Michejda, Christopher J.; Bujacz, Grzegorz D.

    2009-07-01

    HIV-1 nonnucleoside reverse transcriptase inhibitors are potentially specific and effective drugs in AIDS therapy. The presence of two aromatic systems with an angled orientation in the molecule of the inhibitor is crucial for interactions with HIV-1 RT. The inhibitor drives like a wedge into the cluster of aromatic residues of RT HIV-1 and restrains the enzyme in a conformation that blocks the chemical step of nucleotide incorporation. Structural studies provide useful information for designing new, more active inhibitors. The crystal structures of four NNRTIs are presented here. The investigated compounds are derivatives of N-benzyl-4-methyl-benzimidazole with various aliphatic and aromatic substituents at carbon 2 positions and a 2,6-dihalogeno-substituted N-benzyl moiety. Structural data reported here show that the conformation of the investigated compounds is relatively rigid. Such feature is important for the nonnucleoside inhibitor binding to HIV-1 reverse transcriptase.

  18. Synthesis of 4, 5-dihydroxy-9, 10-dioxoanthracene-2- benzyl carboxylate ester from rhein

    Directory of Open Access Journals (Sweden)

    K. S. Laddha

    2012-07-01

    Full Text Available Rhein and several analogues thereof, are particularly important from commercial point of view and are known for their use in the treatment of degenerative diseases of the joints, for example osteoarthritis, osteoporosis and rheumatoid arthritis. Rhein occurs in nature in plant families such as Cassia, Rheum and Rhamnus, but in a very less concentration. Aloin, a natural substance isolated from various species of aloe, consist almost exclusively of barbaloin (10-β-glucopyranosyl-1, 8-dihydroxy-3-hydroxymethyl-anthracen-9-one. Barbaloin, the C-glycoside of aloe-emodin anthrone, localizes in the outer rind of the aloe vera leaf, has been reported to constitute upto 30% of aloe plants dried leaf exudate and proposed as a part of defense mechanism against herbivores. In this paper, an attempt has been made to prepare rhein from barbaloin via formation of aloe-emodin and its chemical modification using benzyl alcohol to prepare its benzyl carboxylate ester.

  19. Flotation of kaolinite and diaspore with hexadecyl dimethyl benzyl ammonium chloride

    Institute of Scientific and Technical Information of China (English)

    HU Yue-hua; OUYANG Kui; CAO Xue-feng; ZHANG Li-min

    2008-01-01

    Tertiary amine was synthesized from fatty amine and formaldehyde. And then the synthesized tertiary amine was used toreact with benzyl chloride to synthesize hexadecyl dimethyl benzyl ammonium chloride (1627) at ambient pressure. Using thesynthesized 1627 as collector, the flotation properties of diaspore and kaolinite were investigated by single mineral and mixedmineral test. The flotation mechanism of diaspore, kaolinite and 1627 was discussed based on FTIR spectra. The results show that themass ratio of aluminum to silicate achieves 15.02 and the recovery of alumina in concentrate is 43.07% using 1627 as a collector. The 1627 is found to be a more effective and a promising collector for reverse flotation to remove aluminum-silicate minerals frombauxite.

  20. Influence of gamma irradiation and benzyl adenine on keeping quality of custard apple fruits during storage

    International Nuclear Information System (INIS)

    The custard apple (Annona squamosa) fruits were procured from local market, irradiated with radiation doses 0, 0.25, 0.50, 0.75, 1.00, 1.25, 1.50, 1.75 kGy and then treated with benzyl adenine (50 and 100 part per million) and stored at ambient temperature (25±5 °C, Relative Humidity 90±2%) for 12 days. The treated fruits were evaluated for sensory (viz; flavour, texture, internal and external colour) and chemical constituents (viz; Total Soluble Solids, titrable acidity, ascorbic acid, free soluble sugar, reducing sugar, non reducing sugar, carbohydrate) during storage. The study concluded that radiation dose of 1.5 kilo Gray along with 50 ppm benzyl adenine enhanced in shelf-life of custard apple fruits by 6 days at ambient temperature with good pulp texture, flavour, colour and nutritional quality as compared to control. (author)

  1. 1,3-Dipolar Cycloaddition Reactions of Substituted Benzyl Azides with Acetylenic Compounds

    Directory of Open Access Journals (Sweden)

    Sultan T. Abu-Orabi

    2002-02-01

    Full Text Available We review in this article some of our work which has been published over the last fifteen years in the area of 1,3-dipolar cycloaddition reactions of substituted benzyl azides with acetylenic compounds to form the corresponding 1,2-3-triazoles. Several triazole derivatives were transformed into triazolopyridazine and triazolo-1,3,4-oxadiazole derivatives upon their reactions with hydrazine.

  2. Inhibition of Human Breast Cancer Xenograft Growth by Cruciferous Vegetable Constituent Benzyl Isothiocyanate

    OpenAIRE

    Warin, Renaud; Xiao, Dong; Arlotti, Julie A.; Bommareddy, Ajay; Singh, Shivendra V

    2010-01-01

    Benzyl isothiocyanate (BITC), a constituent of cruciferous vegetables such as gardencress, inhibits growth of human breast cancer cell lines in culture. The present study was undertaken to determine in vivo efficacy of BITC against MDA-MB-231 human breast cancer xenografts. The BITC administration retarded growth of MDA-MB-231 cells subcutaneously implanted in female nude mice without causing weight loss or any other side effects. The BITC-mediated suppression of MDA-MB-231 xenograft growth c...

  3. Ultrasonic Investigations of Molecular Interaction in Binary Mixtures of Benzyl Benzoate with Acetonitrile and Benzonitrile

    OpenAIRE

    N. Jaya Madhuri; Naidu, P S; Glory, J.; K. Ravindra Prasad

    2011-01-01

    Ultrasonic velocity, density and viscosity have been measured in the binary mixtures of benzyl benzoate with acetonitrile, benzonitrile at three temperatures 30, 40 and 50 °C. From the experimental data, thermodynamic parameters like adiabatic compressibility, internal pressure, enthalpy, activation energy etc., were computed and the molecular interactions were predicted based on the variation of excess parameters in the mixture. Also theoretical evaluation of velocities was made employing th...

  4. Linear free energy relationship in reactions between diphenyl amine and benzyl bromides

    Indian Academy of Sciences (India)

    S Ranga Reddy; P Manikyamba

    2006-05-01

    Rate of reaction between benzyl bromide and diphenyl amine is retarded by electron-donating groups and enhanced by electron-withdrawing groups present on the benzene ring of the substrate. Hammett's reaction constant of the reaction decreases with increase in temperature according to the equation, \\rho = -11.92 + 3.54/ T. Minimal structural effects observed are attributed to the fact that the isokinetic temperature of the reaction is close to the reaction temperature.

  5. Use of cyclodextrins as a cosmetic delivery system for fragrance materials: Linalool and benzyl acetate

    OpenAIRE

    Numanoğlu, Ulya; Şen, Tangül; Tarimci, Nilüfer; Murat KARTAL; Koo, Otilia M. Y.; Önyüksel, Hayat

    2007-01-01

    The aim of this study was to increase the stability and water solubility of fragrance materials, to provide controlled release of these compounds, and to convert these substances from liquid to powder form by preparing their inclusion complexes with cyclodextrins (CDs). For this purpose, linalool and benzyl acetate were chosen as the fragrance materials. The use of β-cyclodextrin (βCD) and 2-hydroxypropyl-β-cyclodextrin (2-HPβCD) for increasing the solubility of these 2 fragrance materials wa...

  6. Carbamate-directed benzylic lithiation for the diastereo- and enantioselective synthesis of diaryl ether atropisomers

    Directory of Open Access Journals (Sweden)

    Abigail Page

    2011-09-01

    Full Text Available Diaryl ethers carrying carbamoyloxymethyl groups may be desymmetrised enantio- and diastereoselectively by the use of the sec-BuLi–(−-sparteine complex in diethyl ether. Enantioselective deprotonation of one of the two benzylic positions leads to atropisomeric products with ca. 80:20 e.r.; an electrophilic quench typically provides functionalised atropisomeric diastereoisomers in up to 97:3 d.r.

  7. Nickel-catalyzed asymmetric reductive cross-coupling between vinyl and benzyl electrophiles.

    Science.gov (United States)

    Cherney, Alan H; Reisman, Sarah E

    2014-10-15

    A Ni-catalyzed asymmetric reductive cross-coupling between vinyl bromides and benzyl chlorides has been developed. This method provides direct access to enantioenriched products bearing aryl-substituted tertiary allylic stereogenic centers from simple, stable starting materials. A broad substrate scope is achieved under mild reaction conditions that preclude the pregeneration of organometallic reagents and the regioselectivity issues commonly associated with asymmetric allylic arylation. PMID:25245492

  8. Nickel-Catalyzed Asymmetric Reductive Cross-Coupling Between Vinyl and Benzyl Electrophiles

    OpenAIRE

    Cherney, Alan H.; Reisman, Sarah E.

    2014-01-01

    A Ni-catalyzed asymmetric reductive cross-coupling between vinyl bromides and benzyl chlorides has been developed. This method provides direct access to enantioenriched products bearing aryl-substituted tertiary allylic stereogenic centers from simple, stable starting materials. A broad substrate scope is achieved under mild reaction conditions that preclude the pregeneration of organometallic reagents and the regioselectivity issues commonly associated with asymmetric allylic arylation.

  9. A radical publishing collective: the Journal of Radical Librarianship

    OpenAIRE

    Simon Barron

    2015-01-01

    The Journal of Radical Librarianship is a new open-access journal publishing scholarly work in the field of radical librarianship. The focus on critical approaches to librarianship and anti-marketisation of information is reflected not only in our subject matter but in our publishing model, our licensing model, and our organisational practices. We hope to foster open and engaging discussions about radical approaches to librarianship and information studies.

  10. Inhibition of a Gold-Based Catalyst in Benzyl Alcohol Oxidation: Understanding and Remediation

    Directory of Open Access Journals (Sweden)

    Emmanuel Skupien

    2014-04-01

    Full Text Available Benzyl alcohol oxidation was carried out in toluene as solvent, in the presence of the potentially inhibiting oxidation products benzaldehyde and benzoic acid. Benzoic acid, or a product of benzoic acid, is identified to be the inhibiting species. The presence of a basic potassium salt (K2CO3 or KF suppresses this inhibition, but promotes the formation of benzyl benzoate from the alcohol and aldehyde. When a small amount of water is added together with the potassium salt, an even greater beneficial effect is observed, due to a synergistic effect with the base. A kinetic model, based on the three main reactions and four major reaction components, is presented to describe the concentration-time profiles and inhibition. The inhibition, as well as the effect of the base, was captured in the kinetic model, by combining strong benzoic acid adsorption and competitive adsorption with benzyl alcohol. The effect of the potassium salt is accounted for in terms of neutralization of benzoic acid.

  11. Oligorotaxane Radicals under Orders.

    Science.gov (United States)

    Wang, Yuping; Frasconi, Marco; Liu, Wei-Guang; Sun, Junling; Wu, Yilei; Nassar, Majed S; Botros, Youssry Y; Goddard, William A; Wasielewski, Michael R; Stoddart, J Fraser

    2016-02-24

    A strategy for creating foldameric oligorotaxanes composed of only positively charged components is reported. Threadlike components-namely oligoviologens-in which different numbers of 4,4'-bipyridinium (BIPY(2+)) subunits are linked by p-xylylene bridges, are shown to be capable of being threaded by cyclobis(paraquat-p-phenylene) (CBPQT(4+)) rings following the introduction of radical-pairing interactions under reducing conditions. UV/vis/NIR spectroscopic and electrochemical investigations suggest that the reduced oligopseudorotaxanes fold into highly ordered secondary structures as a result of the formation of BIPY(•+) radical cation pairs. Furthermore, by installing bulky stoppers at each end of the oligopseudorotaxanes by means of Cu-free alkyne-azide cycloadditions, their analogous oligorotaxanes, which retain the same stoichiometries as their progenitors, can be prepared. Solution-state studies of the oligorotaxanes indicate that their mechanically interlocked structures lead to the enforced interactions between the dumbbell and ring components, allowing them to fold (contract) in their reduced states and unfold (expand) in their fully oxidized states as a result of Coulombic repulsions. This electrochemically controlled reversible folding and unfolding process, during which the oligorotaxanes experience length contractions and expansions, is reminiscent of the mechanisms of actuation associated with muscle fibers. PMID:27163033

  12. Bursectomy at radical gastrectomy

    Institute of Scientific and Technical Information of China (English)

    Cuneyt; Kayaalp

    2015-01-01

    Radical gastrectomy with extended lymph node dissec tion and prophylactic resection of the omentum, peri toneum over the posterior lesser sac, pancreas and/o spleen was advocated at the beginning of the 1960 s in Japan. In time, prophylactic routine resections of the pancreas and/or spleen were abandoned because of the high incidence of postoperative complications. However omentectomy and bursectomy continued to be standard parts of traditional radical gastrectomy. The bursaomentalis was thought to be a natural barrier against invasion of cancer cells into the posterior part of the stomach. The theoretical rationale for bursectomy was to reduce the risk of peritoneal recurrences by eliminating the peritoneum over the lesser sac, which might include free cancer cells or micrometastases. Over time, the indication for bursectomy was gradually reduced to only patients with posterior gastric wall tumors penetrating the serosa. Despite its theoretical advantages, its benefit for recurrence or survival has not been proven yet. The possible reasons for this inconsistency are discussed in this review. In conclusion, the value of bursectomy in the treatment of gastric cancer is still under debate and large-scale randomized studies are necessary. Until clear evidence of patient benefit is obtained, its routine use cannot be recommended.

  13. Tri-n-butyltin hydride-mediated radical reactions of ortho-and meta-iodobenzamides to synthesize benzomacrolactams: surprising formation of biphenyl compounds from meta-regioisomers

    International Nuclear Information System (INIS)

    Reactions of methyl 4-O-allyl-2,3-di-O-benzyl-6-deoxy-6-(3-iodobenzoylamino) -α-D-galactopyranoside, its gluco epimer, methyl 2,3-di-O-benzyl-6-deoxy-6-(3-iodobenzoylamino)- 4-O-(1-pentenyl)-α-D-glucopyranoside and its ortho-regioisomer with tri-n-butyltin hydride were performed in different conditions. Depending on reaction conditions the three meta-iodo isomers gave a surprising amount of biphenyl compounds. The 2-iodo isomer led only to the undesired but expected hydrogenolysis product. No cyclized products were isolated in all the reactions. The structures of the new biphenyl products were elucidated by 1H and 13C NMR spectroscopy, DEPT, COSY, HMQC and HMBC experiments and ESI-MS/MS. Mechanisms for the formation of these new biphenyl derivatives and hypotheses to explain the different outcomes for radical reactions of 3- or 2-iodobenzamides were presented. (author)

  14. Radical cystectomy in eldery

    Directory of Open Access Journals (Sweden)

    Bančević Vladimir

    2015-01-01

    Full Text Available Background/Aim. Radical cystectomy is the method of choice for the treatment of muscle invasive bladder cancer. This major surgery is associated with many complications, especially in older patients. The aim of this study was to analyze preoperative comorbidity, and intraoperative and postoperative complicatons in patients older than 75 years. Methods. This clinical, retrospective study included 46 patients over 75 years, who underwent radical cystectomy. Indications for surgery, and complications during and after the surgery were followed up. Results. Preoperatively, anemia caused by hematuria was registered in 76% of the patients. In 52% of the patients urine derivation was performed by ileal conduit, in 35% by ureterocutaneostomy and in 13% orthotopic ileal neobladder was created. The average duration of surgery was 190 (120-300 min. A total of 76% of the patients were treated by blood supstitution intraoperatively, average 630 (310-1230 mL. Concerning pathological stage of transitional cell carcinoma of urinary bladder, 26% of the patients had T2, 4% T3a, 52% T3b, and 14% T4a stage. In one case, planocellular carcinoma was diagnosed by patohistological examination, and in 2 cases prostate carcinoma was incidentally found. The average duration of hospitalization was 16 (8-35 days. Conclusion. The main reason for cystectomy in patients over 70 and 80 years was gross hematuria caused by bladder cancer, with consecutive anemia which could not be solved using endoscopic treatment or blood supstitution. As expected, a prolonged stay in hospital after cystectomy, and a higher rate of complications were recorded in this population.

  15. Initial evaluation of 227Th-p-benzyl-DOTA-rituximab for low-dose rate α-particle radioimmunotherapy

    International Nuclear Information System (INIS)

    Radioimmunotherapy has proven clinically effective in patients with non-Hodgkin's lymphoma. Radioimmunotherapy trials have so far been performed with β-emitting isotopes. In contrast to β-emitters, the shorter range and high linear energy transfer (LET) of α particles allow for more efficient and selective killing of individually targeted tumor cells. However, there are several obstacles to the use of α-particle immunotherapy, including problems with chelation chemistry and nontarget tissue toxicity. The α-emitting radioimmunoconjugate 227Th-DOTA-p-benzyl-rituximab is a new potential anti-lymphoma agent that might overcome some of these difficulties. The present study explores the immunoreactivity, in vivo stability and biodistribution, as well as the effect on in vitro cell growth, of this novel radioimmunoconjugate. To evaluate in vivo stability, uptake in balb/c mice of the α-particle-emitting nuclide 227Th alone, the chelated form, 227Th-p-nitrobenzyl-DOTA and the radioimmunoconjugate 227Th-DOTA-p-benzyl-rituximab was compared in a range of organs at increasing time points after injection. The immunoreactive fraction of 227Th-DOTA-p-benzyl-rituximab was 56-65%. During the 28 days after injection of radioimmunoconjugate only, very modest amounts of the 227Th had detached from DOTA-p-benzyl-rituximab, indicating a relevant stability in vivo. The half-life of 227Th-DOTA-p-benzyl-rituximab in blood was 7.4 days. Incubation of lymphoma cells with 227Th-DOTA-p-benzyl-rituximab resulted in a significant antigen-dependent inhibition of cell growth. The data presented here warrant further studies of 227Th-DOTA-p-benzyl-rituximab

  16. 2-Acetamido-N-benzyl-1,4-imino-1,2,4-tride­oxy-l-xylitol (N-benzyl-l-XYLNAc)

    Science.gov (United States)

    Jenkinson, Sarah. F.; Crabtree, Elizabeth. V.; Glawar, Andreas. F. G.; Butters, Terry D.; Fleet, George. W. J.; Watkin, David. J.

    2010-01-01

    X-ray crystallography defines the relative configuration at the three-stereogenic centres in the title compound N-benzyl-l-XYLNAc, C14H20N2O3. The five-membered pyrrolidine ring adopts an envelope conformation with the N atom lying out of the plane of the other four atoms. In the crystal structure, inter­molecular O—H⋯O, N—H⋯O and O—H⋯N hydrogen bonds link the mol­ecules into chains along [100]. The carbonyl group O atom acts as an acceptor for a bifurcated hydrogen bond. The absolute configuration is determined by the use of l-glucuronolactone as the starting material for the synthesis. PMID:21579195

  17. 2-Acetamido-N-benzyl-1,4-imino-1,2,4-trideoxy-l-xylitol (N-benzyl-l-XYLNAc

    Directory of Open Access Journals (Sweden)

    Sarah. F. Jenkinson

    2010-05-01

    Full Text Available X-ray crystallography defines the relative configuration at the three-stereogenic centres in the title compound N-benzyl-l-XYLNAc, C14H20N2O3. The five-membered pyrrolidine ring adopts an envelope conformation with the N atom lying out of the plane of the other four atoms. In the crystal structure, intermolecular O—H...O, N—H...O and O—H...N hydrogen bonds link the molecules into chains along [100]. The carbonyl group O atom acts as an acceptor for a bifurcated hydrogen bond. The absolute configuration is determined by the use of l-glucuronolactone as the starting material for the synthesis.

  18. Studies of radiation-produced radicals and radical ions

    International Nuclear Information System (INIS)

    The radiolytic oxidation of anti-5-methylbicyclo[2.1.0]pentane gives the 1-methylcyclopentene radical cation as the sole rearrangement product H migration whereas oxidation of its syn isomer results in the highly selective formation of the 3-methylcyclopentene radical cation by methyl group migration. Since exactly the same stereoselectivity of olefin formation was observed in corresponding PET (photosensitized electron transfer) studies in the liquid phase, it is concluded that the rearrangement in this case also occurs through the intermediacy of radical cations. Clearly, the radical cation rearrangement must occur very rapidly (10-8--10-9s) under liquid-phase conditions at room temperature to compete with back electron transfer, and therefore the hydrogen (or methyl) migration is a fast process under these conditions. An intramolecular cycloaddition reaction was demonstrated in the radical cation rearrangement of 4-vinylcyclohexene to bicyclo[3.2.1]oct-2-ene. ESR studies show that the radiolytic oxidation of quadricyclane in Freon matrices under conditions of high substrate dilution leads to the bicyclo[3.2.0]hepta-2,6-diene radical cation as well as the previously reported norbornadiene radical cation, the former species predominating at sufficiently low concentrations

  19. Synthesis and antimicrobial activities of 1-(3-benzyl-4-oxo-3H-quinazolin-2-yl-4-(substitutedthiosemicarbazide derivatives

    Directory of Open Access Journals (Sweden)

    Alagarsamy Veerachamy

    2015-01-01

    Full Text Available A series of 1-(3-benzyl-4-oxo-3H-quinazolin-2-yl-4-(substituted thiosemicarbazides (AS1-AS10 were obtained by the reaction of 2-hydrazino- 3-benzyl quinazolin-4(3H-one (6 with different dithiocarbamic acid methyl ester derivatives. The key intermediate 3-benzyl-2-thioxo-2,3-dihydro-1Hquinazolin-4-one (4 was obtained by reacting benzyl amine (1 with carbon disulphide and sodium hydroxide in dimethyl sulphoxide to give sodium dithiocarbamate, which was methylated with dimethyl sulfate to yield the dithiocarbamic acid methyl ester (2 and condensed with methyl anthranilate (3 in ethanol yielded the desired compound (4 via the thiourea intermediate. The SH group of compound (4 was methylated for the favorable nucleophilic displacement reaction with hydrazine hydrate, which afford 2-hydrazino-3- benzyl-3H-quinazolin-4-one (6. The IR, 1H, and 13C NMR spectrum of these compounds showed the presence of peaks due to thiosemicarbazides, carbonyl (C=O, NH and aryl groups. The quinazolin-4-one moiety molecular ion peaks (m/z 144 were observed all the mass spectrum of compounds (AS1-AS10. Elemental (C, H, N analysis satisfactorily confirmed purity of the synthesized compounds and elemental composition. All synthesized compounds were also screened for their antimicrobial activity against selective gram positive and gram negative by agar dilution method. In the present study compounds AS8 and AS9 were emerged as the most active compounds of the series.

  20. [99mTcN]-N-benzyl piperidine dithiocarbamate: A potential sigma receptor imaging agent

    International Nuclear Information System (INIS)

    Full text: High expression of sigma receptors in central nervous system suggest their possible role in drug design for diseases such as psychiatric and movement disorders, amnesia, depression and cancer. Herein we report an attempt to target sigma receptors localized in the brain using an analogue of piperidine, a molecule known to exhibit affinity for the brain. 4-amino-N-benzyl piperidine was derivatized to its dithiocarbamate (DTC), known to be a suitable chelating system for complexation with the [99mTcN]2+ precursor. The radiolabeled complex, [99mTcN]- 4-dithiocarbamato-N-benzyl piperidine, was obtained by addition of 50μg(2x10-4M) of the dithiocarbamate to the preformed 99mTcN precursor and characterized by HPLC. Since the sigma receptors are also over-expressed in a large variety of human tumours such as glioma, neuroblastoma, melanoma, breast cancer etc., the radiolabeled piperidine analogue was tested for its affinity towards cancer cells. In vitro studies in the breast cancer cell line MCF-7 and fibrosarcoma cells were carried out by incubating ∼105 cells with ∼20 ng of [99mTcN]-4-dithiocarbamato-N-benzyl piperidine. Specificity of [99mTcN]-4-dithiocarbamato- N-benzyl piperidine was ascertained by inhibition studies with 15 μg pentazocine, a sigma-receptor specific ligand. Pharmacokinetics of the product was studied in normal Swiss mice. 99mTcN complex of piperidine could be radiolabeled in >98% yield. HPLC pattern revealed single species with retention time of 15 min. In vitro binding with MCF-7 was ∼1% and there was ∼75% inhibition after pre-incubation of cells with pentazocine whereas with fibrosarcoma the values were 2% and 55%, respectively. In biodistribution studies in normal mice, brain uptake of ∼0.6 ID/gm at 5min.p.i. was observed which reduced to 0.3%ID/g at 2h.p.i. Significant uptake in other vital tissues such as heart, lungs, liver and kidneys expressing sigma receptors was also observed. Administration of Pentazocine one hour

  1. Gold( i )-catalysed dehydrative formation of ethers from benzylic alcohols and phenols

    KAUST Repository

    Veenboer, Richard M. P.

    2015-01-01

    © The Royal Society of Chemistry 2015. We report the cross-dehydrative reaction of two alcohols to form unsymmetrical ethers using NHC-gold(i) complexes (NHC = N-heterocyclic carbene). Our progress in developing this reaction into a straightforward procedure is discussed in detail. The optimised methodology proceeds under mild reaction conditions and produces water as the sole by-product. The synthetic utility of this environmentally benign methodology is exemplified by the formation of a range of new ethers from readily available phenols bearing electron withdrawing substituents and secondary benzylic alcohols with various substituents. Finally, we present experimental results to account for the chemoselectivity obtained in these reactions.

  2. Investigation of comparative efficacy of eugenol and benzyl benzoate in therapy of sheep mange

    OpenAIRE

    Jezdimirović Milanka; Aleksić Nevenka; Radojičić Biljana

    2010-01-01

    The acaricide efficacy, tolerance and safety of eugenol (10 and 20 %) in the treatment of sarcoptic mange in sheep have been investigated. The results were compared with those corresponding for benzyl benzoate (25 %), which was applied to sheep in the same way. The treatment was applied on sheep three times in one-week intervals. Skin scrapings were sampled seven days after each treatment, as well as twenty-eight days following the third one. The changes on the skin were quantified and the me...

  3. Synthesis and biological evaluation of colchicine B-ring analogues tethered with halogenated benzyl moieties.

    Science.gov (United States)

    Cosentino, Laura; Redondo-Horcajo, Mariano; Zhao, Ying; Santos, Ana Rita; Chowdury, Kaniz F; Vinader, Victoria; Abdallah, Qasem M A; Abdel-Rahman, Hamdy; Fournier-Dit-Chabert, Jérémie; Shnyder, Steven D; Loadman, Paul M; Fang, Wei-shuo; Díaz, José Fernando; Barasoain, Isabel; Burns, Philip A; Pors, Klaus

    2012-12-27

    Deacetylcolchicine was reacted with substituted benzyl halides to provide a library of compounds for biological analysis. Compound 7 (3,4-difluorobenzyl-N-aminocolchicine) was shown to possess cytotoxicity in cancer cell lines in the low nanomolar range. Significantly, it showed no loss of activity in the resistant A2780AD ovarian carcinoma cell line known to overexpress the ABCB1 drug transporter and was also unaffected by overexpression of class III β-tubulin in HeLa transfected cells. PMID:23176628

  4. A Sustainable and Efficient Synthesis of Benzyl Phosphonates Using PEG/KI Catalytic System.

    Science.gov (United States)

    Disale, Shamrao; Kale, Sandip; Abraham, George; Kahandal, Sandeep; Sawarkar, Ashish N; Gawande, Manoj B

    2016-01-01

    An efficient and expedient protocol for the synthesis of benzyl phosphonates using KI/K2CO3 as a catalytic system and PEG-400 as benign solvent has been developed. The reaction proceeds smoothly at room temperature achieving excellent selectivity and yield of the corresponding products. The combination of PEG-400, KI, and K2CO3 in this reaction avoids the need of volatile/toxic organic solvents and reactive alkali metals or metal nanoparticles/hydrides. We believe that this benign combination (PEG-400 and KI) could be used for other related organic transformations. PMID:27579301

  5. Mild and selective vanadium-catalyzed oxidation of benzylic, allylic, and propargylic alcohols using air.

    Science.gov (United States)

    Hanson, Susan K; Wu, Ruilian; Silks, L A Pete

    2011-04-15

    Transition metal-catalyzed aerobic alcohol oxidation is an attractive method for the synthesis of carbonyl compounds, but most catalytic systems feature precious metals and require pure oxygen. The vanadium complex (HQ)(2)V(V)(O)(O(i)Pr) (2 mol %, HQ = 8-quinolinate) and NEt(3) (10 mol %) catalyze the oxidation of benzylic, allylic, and propargylic alcohols with air. The catalyst can be easily prepared under air using commercially available reagents and is effective for a wide range of primary and secondary alcohols. PMID:21434606

  6. (E)-N′-(2-Benzyl­oxybenzyl­idene)isonicotinohydrazide methanol solvate monohydrate

    OpenAIRE

    H. S. Naveenkumar; Sadikun, Amirin; Ibrahim, Pazilah; Hemamalini, Madhukar; Fun, Hoong-Kun

    2010-01-01

    The title compound, C20H17N3O2·CH4O·H2O, was synthesized by the condensation reaction of 2-benzyl­oxybenzaldehyde with isoniazid (isonicotinic acid hydrazide). The tricyclic compound displays a trans configuration with respect to the C=N double bond. The central benzene ring makes dihedral angles of 8.83 (7) and 70.39 (8)° with the pyridine ring and the terminal benzene ring, respectively. The dihedral angle between the pyridine ring and the terminal benzene ring is 73.11 (8)°. In the crystal...

  7. Development of Highly Effective Nanoparticle Spinel Catalysts for Aerobic Oxidation of Benzylic Alcohols

    Institute of Scientific and Technical Information of China (English)

    JI,Hong-Bing(纪红兵); WANG,Le-Fu(王乐夫)

    2002-01-01

    Spinel catalyst MnFe1.8Cu0.15Ru0.05O4 with particle size of about 42 nm is an effective heterogeneous catalyst for the oxidation of benzylic alcohols. The substitution of Fe for Cu improves its catalytic activity. Based on the characterization of BET, XPS and EXAFS, two factors influencing the structure and texture of the catalyst caused by the substitution of Cu for Fe may be assumed: physical factor responsible for the increasing of surface area; chemical factor responsible for the transformation of Ru-O bonds to Ru = O bonds. β-Elimination is considered to be an important step in the reaction.

  8. Radical production in biological systems

    International Nuclear Information System (INIS)

    This paper describes our effort to develop a metric for radiation exposure that is more fundamental than adsorbed dose and upon which a metric for exposure to chemicals could be based. This metric is based on the production of radicals by the two agents. Radicals produced by radiation in biological systems commonly assumed to be the same as those produced in water despite the presence of a variety of complex molecules. This may explain why the extensive efforts to describe the relationship between energy deposition (track structure) and molecular damage to DNA, based on the spectrum of radicals produced, have not been successful in explaining simple biological effects such as cell killing. Current models assume that DNA and its basic elements are immersed in water-like media and only model the production and diffusion of water-based radicals and their interaction with DNA structures; these models lack the cross sections associated with each macro-component of DNA and only treat water-based radicals. It has been found that such models are not realistic because DNA is not immersed in pure water. A computer code capable of simulating electron tracks, low-energy electrons, energy deposition in small molecules, and radical production and diffusion in water like media has been developed. This code is still in at a primitive stage and development is continuing. It is being used to study radical production by radiation, and radical diffusion and interactions in simple molecular systems following their production. We are extending the code to radical production by chemicals to complement our PBPK modeling efforts. It therefore has been developed primarily for use with radionuclides that are in biological materials, and not for radiation fields

  9. Guest Editorial: Processes of Radicalization and De-Radicalization

    Directory of Open Access Journals (Sweden)

    Donatella Della Porta

    2012-05-01

    Full Text Available The study of radicalization and de-radicalization, understood as processes leading towards the increased or decreased use of political violence, is central to the question of how political violence emerges, how it can be prevented, and how it can be contained. The focus section of this issue of the International Journal of Conflict and Violence addresses radicalization and de-radicalization, seeking to develop a more comprehensive understanding of the processes, dynamics, and mechanisms involved and taking an interdisciplinary approach to overcome the fragmentation into separate disciplines and focus areas. Contributions by Pénélope Larzillière, Felix Heiduk, Bill Kissane, Hank Johnston, Christian Davenport and Cyanne Loyle, Veronique Dudouet, and Lasse Lindekilde address repressive settings, legitimacy, institutional aspects, organizational outcomes, and dynamics in Europe, Asia, Africa, and North and South America.

  10. Multifunctional radical-doped polyoxometalate-based host-guest material: photochromism and photocatalytic activity.

    Science.gov (United States)

    Liao, Jian-Zhen; Zhang, Hai-Long; Wang, Sa-Sa; Yong, Jian-Ping; Wu, Xiao-Yuan; Yu, Rongmin; Lu, Can-Zhong

    2015-05-01

    An effective strategy to synthesize multifunctional materials is the incorporation of functional organic moieties and metal oxide clusters via self-assembly. A rare multifunctional radical-doped zinc-based host-guest crystalline material was synthesized with a fast-responsive reversible ultraviolet visible light photochromism, photocontrolled tunable luminescence, and highly selective photocatalytic oxidation of benzylic alcohols as a result of blending of distinctively different functional components, naphthalenediimide tectons, and polyoxometalates (POMs). It is highly unique to link π-electron-deficient organic tectons and POMs by unusual POMs anion-π interactions, which are not only conducive to keeping the independence of each component but also effectively promoting the charge transfer or exchange among the components to realize the fast-responsive photochromism, photocontrolled tunable luminescence, and photocatalytic activity. PMID:25859742

  11. Synthesis of Nickel Hexacyanoferrate Nanoparticles and Their Potential as Heterogeneous Catalysts for the Solvent-Free Oxidation of Benzyl Alcohol

    Institute of Scientific and Technical Information of China (English)

    Shah R. ALI; Prakash CHANDRA; Mamta LATWAL; Shalabh K. JAIN; Vipin K. BANSAL; Sudhanshu P. SINGH

    2011-01-01

    Nickel hexacyanoferrate nanoparticles were synthesized and characterized using elemental analysis,thermal analysis,infrared spectroscopy,and X-ray diffraction.A FE-SEM image of the nickel hexacyanoferrate showed that it consists of nearly spherical particles with sizes ranging from 30 to 70 nm.The synthesized material was found to be a heterogeneous catalyst useful for the solvent-free oxidation of benzyl alcohol with H2O2 as an oxidant.A 36% conversion of benzyl alcohol to benzaldehyde was achieved under optimized reaction conditions using specific parameters such as the amount of catalyst,the temperature,the benzyl alcohol to H2O2 molar ratio,and the reaction time.

  12. Redox Properties of Free Radicals.

    Science.gov (United States)

    Neta, P.

    1981-01-01

    Describes pulse radiolysis as a useful means in studing one-electron redox potentials. This method allows the production of radicals and the determination of their concentration and rates of reaction. (CS)

  13. Nickel(ii) radical complexes of thiosemicarbazone ligands appended by salicylidene, aminophenol and aminothiophenol moieties.

    Science.gov (United States)

    Kochem, Amélie; Gellon, Gisèle; Jarjayes, Olivier; Philouze, Christian; du Moulinet d'Hardemare, Amaury; van Gastel, Maurice; Thomas, Fabrice

    2015-07-28

    The nickel(ii) complexes of three unsymmetrical thiosemicarbazone-based ligands featuring a sterically hindered salicylidene (1), aminophenol (2) or thiophenol (3) moiety were synthesized and structurally characterized. The metal ion lies in an almost square planar geometry in all the complexes. The cyclic voltammetry (CV) curve of 1 shows an irreversible oxidation wave at E = 0.49 V, which is assigned to the phenoxyl/phenolate redox couple. The CV curves of 2 and 3 display a reversible one-electron oxidation wave (E1/2 = 0.26 and 0.22 V vs. Fc(+)/Fc, respectively) and an one-electron reduction wave (E1/2 = -1.55 and -1.46 V, respectively). The cations 2(+) and 3(+) as well as the anions 2(-) and 3(-) were generated. The EPR spectra of the cations in THF show a rhombic signal at g1 = 2.034, g2 = 2.010 and g3 = 1.992 (2(+)) and g1 = 2.069, g2 = 2.018, g3 = 1.986 (3(+)) that is consistent with a main radical character of the complexes. The difference in anisotropy is assigned to the different nature of the radical, iminosemiquinonate vs. iminothiosemiquinonate. The anions display an isotropic EPR signal at giso = 2.003 (2(+)) and 2.006 (3(+)), which is indicative of a main α-diimine radical character of the compounds. Both the anions and cations exhibit charge transfer transitions of low to moderate intensity in their visible spectrum. Quantum chemical calculations (B3LYP) reproduce both the g-values and Vis-NIR spectra of the complexes. The radical anions readily react with dioxygen to give the radical cations. 2(+) catalyzes the aerobic oxidation of benzyl alcohol into benzaldehyde. PMID:26086684

  14. Radical polymerization of monoethyl itaconate

    OpenAIRE

    Katsikas Lynne; Nišević Nataša; Ignjatović Milka; Adamović Vladimir; Đakov Tatjana A.; Popović Ivanka G.

    2003-01-01

    The radical polymerization of monoethyl itaconate (MEI) was investigated in bulk and in solution at 60°C using a,a'-azobisisobutyronitrile as initiator. It was established that the obtained polymer poly(monoethyl itaconate) was insoluble in its monomer, implying that the bulk polymerization of MEI was a precipitation polymerization. The polymerization kinetics of MEI were discussed and compared to the polymerization kinetics of structurally similar alkyl itaconates. The homogeneous radical po...

  15. Ecoporn, Irrationalities and Radical Environmentalism

    OpenAIRE

    Măntescu, Liviu

    2016-01-01

    This study explores the ‘irrationalities’ of deep ecology activism in the context of radical environmentalism by using the empirical example of ecoporn. Fuck For Forest is an environmental Non-Governmental Organisation which undertakes fund-raising for re-forestation and forest protection by means of pornography. Following twelve months of ethnographic fieldwork, this study presents first research results on a radical environmental project which does not promote democratic and established pro...

  16. FORMULATION AND EVALUATION OF GOAT FAT AND SHEA BUTTER BASED LIPOSPHERES OF BENZYL PENICILLIN

    Directory of Open Access Journals (Sweden)

    C.D. Nwakile et al.

    2012-04-01

    Full Text Available Lipospheres of benzyl penicillin were formulated using the conventional thin film hydration technique. Five different combinations of shea butter, surfactant (Span 80 and goat fat were the key variables employed in the formulations. The resultant lipospheres were evaluated with respect to surface morphology, particle size distribution, encapsulation efficiency, in vitro drug release, in vivo bioavailability and in vitro antimicrobial activity. Particle size was found to increase with increased drug loading, the average particle radius of the batches being 12.5 nm. The encapsulation efficiency was found to be high at all levels with encouraging values of 80.21 and 83.44 % for batch A and E respectively, with batch A containing shea butter and span 80 in the ratio of 1:1 and batch E containing shea butter, span 80 and goat fat in the ratio of 1:2:1. Batch A appear to exhibit sustained release in vitro with cumulative drug release being 60 % while batch E has a cumulative drug release of 98 % respectively. The presence of goat fat however seems to impact negatively on the in vivo stability of batch E liposphere. The test micro-organisms showed sensitivity to the two batches in marked contrast to the uncapsulated benzyl penicillin especially against the multiple-antibiotic resistant strains of S. typhi, P. vulgaris and P. aereuginosa used in the study.

  17. Highly Dispersed Gold Nanoparticles Supported on SBA-15 for Vapor Phase Aerobic Oxidation of Benzyl Alcohol.

    Science.gov (United States)

    Kumar, Ashish; Sreedhar, Bojja; Chary, Komandur V R

    2015-02-01

    Gold nanoparticles supported on SBA-15 are prepared by homogenous deposition-precipitation method (HDP) using urea as the precipitating agent. The structural features of the synthesized catalysts were characterized by various techniques such as X-ray diffraction (XRD), transmission electron microscopy (TEM), nitrogen adsorption-desorption (BET), pore size distribution (PSD), CO chemisorption and X-ray photoelectron spectroscopy (XPS). The catalytic activity and stability of the Au/SBA-15 catalysts are investigated during the vapor phase aerobic oxidation of benzyl alcohol. The BJH pore size distribution results of SBA-15 support and Au/SBA-15 catalysts reveals that the formation of mesoporous structure in all the samples. TEM results suggest that Au nanoparticles are highly dispersed over SBA-15 and long range order of hexagonal mesopores of SBA-15 is well retained even after the deposition of Au metallic nanoparticles. XPS study reveals the formation of Au (0) after chemical reduction by NaBH4. The particle size measured from CO-chemisorption and TEM analysis are well correlated with the TOF values of the reaction. Au/SBA-1 5 catalysts are found to show higher activity compare to Au/TiO2 and Au/MgO catalysts during the vapor phase oxidation of benzyl alcohol. The catalytic functionality are well substantiated with particle size measured from TEM. The crystallite size of Au in both fresh and spent catalysts were measured from X-ray diffraction. PMID:26353720

  18. Antichagasic and trichomonacidal activity of 1-substituted 2-benzyl-5-nitroindazolin-3-ones and 3-alkoxy-2-benzyl-5-nitro-2H-indazoles.

    Science.gov (United States)

    Fonseca-Berzal, Cristina; Ibáñez-Escribano, Alexandra; Reviriego, Felipe; Cumella, José; Morales, Paula; Jagerovic, Nadine; Nogal-Ruiz, Juan José; Escario, José Antonio; da Silva, Patricia Bernardino; Soeiro, Maria de Nazaré C; Gómez-Barrio, Alicia; Arán, Vicente J

    2016-06-10

    Two series of new 5-nitroindazole derivatives, 1-substituted 2-benzylindazolin-3-ones (6-29, series A) and 3-alkoxy-2-benzyl-2H-indazoles (30-37, series B), containing differently functionalized chains at position 1 and 3, respectively, have been synthesized starting from 2-benzyl-5-nitroindazolin-3-one 5, and evaluated against the protozoan parasites Trypanosoma cruzi and Trichomonas vaginalis, etiological agents of Chagas disease and trichomonosis, respectively. Many indazolinones of series A were efficient against different morphological forms of T. cruzi CL Brener strain (compounds 6, 7, 9, 10 and 19-21: IC50 = 1.58-4.19 μM for epimastigotes; compounds 6, 19-21 and 24: IC50 = 0.22-0.54 μM for amastigotes) being as potent as the reference drug benznidazole. SAR analysis suggests that electron-donating groups at position 1 of indazolinone ring are associated with an improved antichagasic activity. Moreover, compounds of series A displayed low unspecific toxicities against an in vitro model of mammalian cells (fibroblasts), which were reflected in high values of the selectivity indexes (SI). Compound 20 was also very efficient against amastigotes from Tulahuen and Y strains of T. cruzi (IC50 = 0.81 and 0.60 μM, respectively), showing low toxicity towards cardiac cells (LC50 > 100 μM). In what concerns compounds of series B, some of them displayed moderate activity against trophozoites of a metronidazole-sensitive isolate of T. vaginalis (35 and 36: IC50 = 9.82 and 7.25 μM, respectively), with low unspecific toxicity towards Vero cells. Compound 36 was also active against a metronidazole-resistant isolate (IC50 = 9.11 μM) and can thus be considered a good prototype for the development of drugs directed to T. vaginalis resistant to 5-nitroimidazoles. PMID:27017556

  19. The games radicals play : special issue on free radicals and radical ions

    OpenAIRE

    Walton, John C; Ffrancon Williams

    2015-01-01

    Chemistry and Physics have aptly been described as “most excellent children of Intellect and Art” [1]. Both these “children” engage with many playthings, and molecules rank as one of their first favorites, especially radicals, which are amongst the most lively and exciting. Checking out radicals dancing to the music of entropy round their potential energy ballrooms is surely both entertaining and enlightening. Radicals’ old favorite convolutions are noteworthy, but the new styles, modes and a...

  20. Crystalline bipyridinium radical complexes and uses thereof

    Energy Technology Data Exchange (ETDEWEB)

    Fahrenbach, Albert C.; Barnes, Jonathan C.; Li, Hao; Stoddart, J. Fraser; Basuray, Ashish Neil; Sampath, Srinivasan

    2015-09-01

    Described herein are methods of generating 4,4'-bipyridinium radical cations (BIPY.sup..cndot.+), and methods for utilizing the radical-radical interactions between two or more BIPY.sup..cndot.+ radical cations that ensue for the creation of novel materials for applications in nanotechnology. Synthetic methodologies, crystallographic engineering techniques, methods of physical characterization, and end uses are described.

  1. Crystalline bipyridinium radical complexes and uses thereof

    Science.gov (United States)

    Fahrenbach, Albert C.; Barnes, Jonathan C.; Li, Hao; Stoddart, J. Fraser; Basuray, Ashish Neil; Sampath, Srinivasan

    2015-09-01

    Described herein are methods of generating 4,4'-bipyridinium radical cations (BIPY.sup..cndot.+), and methods for utilizing the radical-radical interactions between two or more BIPY.sup..cndot.+ radical cations that ensue for the creation of novel materials for applications in nanotechnology. Synthetic methodologies, crystallographic engineering techniques, methods of physical characterization, and end uses are described.

  2. Peroxy radical partitioning during the AMMA radical intercomparison exercise

    Directory of Open Access Journals (Sweden)

    M. D. Andrés-Hernández

    2010-11-01

    Full Text Available Peroxy radicals were measured onboard two scientific aircrafts during the AMMA (African Monsoon Multidisciplinary Analysis campaign in summer 2006. This paper reports results from the flight on 16 August 2006 during which measurements of HO2 by laser induced fluorescence spectroscopy at low pressure (LIF-FAGE and total peroxy radicals (RO2* = HO2+ΣRO2, R = organic chain by two similar instruments based on the peroxy radical chemical amplification (PeRCA technique were subject of a blind intercomparison. The German DLR-Falcon and the British FAAM-BAe-146 flew wing tip to wing tip for about 30 min making concurrent measurements on 2 horizontal level runs at 697 and 485 hPa over the same geographical area in Burkina Faso. A full set of supporting measurements comprising photolysis frequencies, and relevant trace gases like CO, NO, NO2, NOy, O3 and a wider range of VOCs were collected simultaneously.

    Results are discussed on the basis of the characteristics and limitations of the different instruments used. Generally, no data bias are identified and the RO2* data available agree quite reasonably within the instrumental errors. The [RO2*]/[HO2] ratios, which vary between 1:1 and 3:1, as well as the peroxy radical variability, concur with variations in photolysis rates and in other potential radical precursors. Model results provide additional information about dominant radical formation and loss processes.

  3. Peroxy radical partitioning during the AMMA radical intercomparison exercise

    Directory of Open Access Journals (Sweden)

    M. D. Andrés-Hernández

    2010-04-01

    Full Text Available Peroxy radicals were measured onboard two scientific aircrafts during the AMMA (African Monsoon Multidisciplinary Analysis campaign in summer 2006. This paper reports results from the flight on 16 August 2006 during which measurements of HO2 by laser induced fluorescence spectroscopy at low pressure (LIF-FAGE and total peroxy radicals (RO2*=HO2+ΣRO2, R= organic chain by two similar instruments based on the peroxy radical chemical amplification (PerCA technique were subject of a blind intercomparison. The German DLR-Falcon and the British FAAM-BAe-146 flew wing tip to wing tip for about 30 min making concurrent measurements on 2 horizontal level runs at 697 and 485 hPa over the same geographical area in Burkina Faso. A full set of supporting measurements comprising photolysis frequencies, and relevant trace gases like CO, NO, NO2, NOy, O3 and a wider range of VOCs were collected simultaneously.

    Results are discussed on the basis of the characteristics and limitations of the different instruments used. Generally, no data bias are identified and the RO2* data available agree quite reasonably within the instrumental errors. The [RO2*]/[HO2] ratios, which vary between 1:1 and 3:1, as well as the peroxy radical variability, concur with variations in photolysis rates and in other potential radical precursors. Model results provide additional information about dominant radical formation and loss processes.

  4. Nuclear magnetic resonance of D(-)-{alpha}-amino-benzyl penicillin; Ressonancia magnetica nuclear da D(-)-{alpha}-amino-benzil penicilina

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Monica R.M.P.; Gemal, Andre L.; San Gil, Rosane A.S. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Quimica; Menezes, Sonia M.C. [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas

    1995-12-31

    The development of new drugs from penicillins has induced the study of this substances by nuclear magnetic resonance. Several samples of D(-)-{alpha}-amino-benzyl penicillin were analysed using {sup 13} C NMR techniques in aqueous solution and solid state. Spectral data of this compounds were shown and the results were presented and analysed 7 figs., 4 tabs.

  5. Aerobic oxidation of benzylic aldehydes to acids catalyzed by iron (Ⅲ) meso-tetraphenylporphyrin chloride under ambient conditions

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Highly efficient aerobic oxidation of benzylic aldehydes to the corresponding acids catalyzed by iron (Ⅲ) meso-tetraphenylporphyrin chloride (Fe(TPP)Cl) under ambient conditions was developed. The catalyst has been proved to be an excellent catalyst for the system in the presence of molecular oxygen and isobutryaldehyde at room temperature.

  6. Study of the Chemical Mechanism Involved in the Formation of Tungstite in Benzyl Alcohol by the Advanced QEXAFS Technique

    DEFF Research Database (Denmark)

    Olliges‐Stadler, Inga; Stötzel, Jan; Koziej, Dorota;

    2012-01-01

    Insight into the complex chemical mechanism for the formation of tungstite nanoparticles obtained by the reaction of tungsten hexachloride with benzyl alcohol is presented herein. The organic and inorganic species involved in the formation of the nanoparticles were studied by time‐dependent gas c...

  7. Synthesis and structure-activity relationships of N-benzyl phenethylamines as 5-HT2A/2C agonists

    DEFF Research Database (Denmark)

    Hansen, Martin; Phonekeo, Karina; Paine, James S; Leth-Petersen, Sebastian; Begtrup, Mikael; Bräuner-Osborne, Hans; Kristensen, Jesper Langgaard

    2014-01-01

    N-benzyl substitution of 5-HT2A receptor agonists of the phenethylamine structural class of psychedelics (such as 4-bromo-2,5-dimethoxyphenethylamine, often referred to as 2C-B) confer a significant increase in binding affinity as well as functional activity of the receptor. We have prepared a...

  8. Synthesis of some novel fluoro isoxazolidine and isoxazoline derivatives using -benzyl fluoro nitrone via cycloaddition reaction in ionic liquid

    Indian Academy of Sciences (India)

    Bhaskar Chakraborty; Govinda Prasad Luitel

    2013-09-01

    1-Butyl-3-methylimidazolium-based ionic liquids are found to accelerate significantly the intermolecular 1,3-dipolar cycloaddition of -benzyl-fluoro nitrone derived in situ from 2,6-difluoro benzaldehyde and -benzylhydroxylamine, with activated alkenes and electron deficient alkynes to afford enhanced rates and improved yields of novel isoxazolidines and isoxazolines.

  9. Ir/Sn dual-reagent catalysis towards highly selective alkylation of arenes and heteroarenes with benzyl alcohols

    Indian Academy of Sciences (India)

    Sujit Roy; Susmita Podder; Joyanta Choudhury

    2008-09-01

    A catalytic combination of [Ir(COD)Cl]2-SnCl4 efficiently promotes the reactions of arenes and heteroarenes with 1°/2°/3° benzyl alcohols as the alkylating agents to afford the corresponding diarylmethane and triarylmethane derivatives in high yields. The scope and limitation of the reaction with respect to catalyst and substrates variation has been studied in detail.

  10. Disposition kinetics and bioavailability of the glucosidase inhibitor N-benzyl-1-deoxynojirimycin after various routes of administration in mice

    NARCIS (Netherlands)

    Faber, ED; Delbressine, LPC; vandeVorstenbosch, CG; vandenBroek, LAGM; Meijer, DKF; Stok, B.P.

    1997-01-01

    Pharmacokinetics, biodistribution, and excretion of the alpha-glucosidase inhibitor and antiviral compound N-benzyl-1-deoxynojirimycin (BndNM) were studied in mice, after intravenous, subcutaneous, and oral administration of a single radiolabeled dose, No metabolites were detected in plasma, urine,

  11. Standard Electrode Potentials Involving Radicals in Aqueous Solution: Inorganic Radicals

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, David A.; Huie, Robert E.; Koppenol, Willem H.; Lymar, Sergei V.; Merenyi, Gabor; Neta, Pedatsur; Ruscic, Branko; Stanbury, David M.; Steenken, Steen; Wardman, Peter

    2015-12-01

    Recommendations are made for standard potentials involving select inorganic radicals in aqueous solution at 25 °C. These recommendations are based on a critical and thorough literature review and also by performing derivations from various literature reports. The recommended data are summarized in tables of standard potentials, Gibbs energies of formation, radical pKa’s, and hemicolligation equilibrium constants. In all cases, current best estimates of the uncertainties are provided. An extensive set of Data Sheets is appended that provide original literature references, summarize the experimental results, and describe the decisions and procedures leading to each of the recommendations

  12. Radical-Enhanced Chinese Character Embedding

    OpenAIRE

    Sun, Yaming; Lin, Lei; Tang, Duyu; Yang, Nan; Ji, Zhenzhou; Wang, Xiaolong

    2014-01-01

    We present a method to leverage radical for learning Chinese character embedding. Radical is a semantic and phonetic component of Chinese character. It plays an important role as characters with the same radical usually have similar semantic meaning and grammatical usage. However, existing Chinese processing algorithms typically regard word or character as the basic unit but ignore the crucial radical information. In this paper, we fill this gap by leveraging radical for learning continuous r...

  13. 3-Benzyl-3-hydroxy-2-phenyl-3H-indole 1-oxide

    Directory of Open Access Journals (Sweden)

    Corrado Rizzoli

    2010-08-01

    Full Text Available The asymmetric unit of the title compound, C21H17NO2, contains two crystallographically independent molecules of similar geometry. The indole ring systems form dihedral angles of 8.30 (5 and 9.58 (5° with the attached phenyl rings, and 56.96 (5 and 57.68 (5° with the aromatic rings of the respective benzyl groups. The molecular conformations are stabilized by intramolecular C—H...O hydrogen bonds. In the crystal structure, centrosymmetrically related pairs of molecules are linked into dimers through pairs of intermolecular O—H...O hydrogen bonds, generating 12-membered rings with R22(12 motifs. The dimers are further linked into a three-dimensional network by C—H...O interactions.

  14. (5E-1-Benzyl-5-(3,3,3-trichloro-2-oxopropylidenepyrrolidin-2-one

    Directory of Open Access Journals (Sweden)

    Alex Fabiani Claro Flores

    2014-06-01

    Full Text Available In the crystal structure of the title compound, C14H12Cl3NO2, no classical hydrogen-bonding interactions are observed. The methylene fragments of the benzyl groups participate in non-classic hydrogen-bond interactions with the carbonyl O atoms of neighboring molecules, generating co-operative centrosymmetric dimers with R55(10 ring motifs. The overall molecular arrangement in the unit cell seems to be highly influenced by secondary non-covalent weak C—Cl...π [Cl...Cg(phenyl ring = 3.732 (2 Å] and C—O...π [O...Cg(pyrrolidine ring = 2.985 (2 Å] contacts.

  15. SYNTHESIS AND CHARACTERIZATION OF SIDE CHAIN LIQUID CRYSTALLINE POLYSILOXANES CONTAINING BENZYL ETHER LINKING UNITS

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Side chain liquid crystalline polysiloxanes containing benzyl ether linking units were synthesized by the hydrosilylation of poly(methylhydrosiloxane) with a series of 4-(4-alkoxybenzyloxy)-4'-allyloxybiphenyl monomers [4-(4-methoxybenzyloxy)-4'-allyloxybiphenyl (M1), 4-(4-ethoxybenzyloxy)-4'-allyloxybiphenyl (M2), 4-(4-propoxybenzyloxy)-4'-allyloxybiphenyl (M3), 4-(4-butoxybenzyloxy)-4'-allyloxybiphenyl (M4), 4-(4-pentoxybenzyloxy)-4'-allyloxybiphenyl (Ms), 4-benzyloxy-4'-allyloxybiphenyl (M6)]. The phase behavior of monomeric and polymeric liquid crystals was characterized by differential scanning calorimetry and optical polarization microscopy where the groups are ranged from methoxy to pentoxy. Both the monomeric and polymeric liquid crystals exhibit liquid crystal behaviors.

  16. Development of Cholinesterase Inhibitors Using (a)-Lipoic Acid-benzyl Piperazine Hybrid Molecules

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Beomcheol; Lee, Seunghwan; Jang, Mi; Shon, Min Young; Park, Jeong Ho [Hanbat National Univ., Daejeon (Korea, Republic of)

    2013-11-15

    A series of hybrid molecules between (α)-lipoic acid (ALA) and benzyl piperazines were synthesized and their in vitro cholinesterase [acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE)] inhibitory activities were evaluated. Even though the parent compounds did not show any inhibitory activity against cholinesterase (ChE), all hybrid molecules showed BuChE inhibitory activity. Some hybrid compounds also displayed AChE inhibitory activity. Specifically, ALA-1-(3-methylbenzyl)piperazine (15) was shown to be an effective inhibitor of both BuChE (IC{sub 50} = 2.3 ± 0.7 μM) and AChE (IC{sub 50} = 30.31 ± 0.64 μM). An inhibition kinetic study using compound 15 indicated a mixed inhibition type. Its binding affinity (K{sub i}) value to BuChE is 2.91 ± 0.15 μM.

  17. Crystal structure of 1-benzyl-4-formyl-1H-pyrrole-3-carb-oxamide.

    Science.gov (United States)

    Zhong, Qi-Di; Hu, Sheng-Quan; Yan, Hong

    2016-02-01

    In the title compound, C13H12N2O2 (I), the mean planes of the pyrrole and benzyl rings are approximately perpendicular, forming a dihedral angle of 87.07 (4) °. There is an intra-molecular N-H⋯O hydrogen bond forming an S(7) ring motif. In the crystal, mol-ecules are linked via a pair of N-H⋯O hydrogen bonds forming inversion dimers. C-H⋯O hydrogen bonds link the dimers into chains along direction [10-1]. The chains are further linked by weak C-H⋯π inter-actions forming layers parallel to the ac plane. PMID:26958371

  18. Electrocarboxylation of benzyl chlorides at silver cathode at the preparative scale level

    Energy Technology Data Exchange (ETDEWEB)

    Scialdone, Onofrio [Dipartimento di Ingegneria Chimica dei Processi e dei Materiali, Universita di Palermo, Viale delle Scienze, 90128 Palermo (Italy)], E-mail: scialdone@dicpm.unipa.it; Galia, Alessandro; Errante, Giuseppina [Dipartimento di Ingegneria Chimica dei Processi e dei Materiali, Universita di Palermo, Viale delle Scienze, 90128 Palermo (Italy); Isse, Abdirisak Ahmed; Gennaro, Armando [Dipartimento di Scienze Chimiche, Universita di Padova, Via Marzolo 1, 35131 Padova (Italy); Filardo, Giuseppe [Dipartimento di Ingegneria Chimica dei Processi e dei Materiali, Universita di Palermo, Viale delle Scienze, 90128 Palermo (Italy)

    2008-01-01

    The electrocarboxylation of benzyl chlorides to the corresponding carboxylic acids performed at silver cathodes was investigated both theoretically and experimentally in order to find the influence of the operative parameters on the selectivity and on the Faradic efficiency of the process. Theoretical considerations were confirmed by the electrocarboxylation of 1-phenyl-1-chloroethane performed in undivided cells equipped with sacrificial anodes both in a bench-scale electrochemical batch reactor and in a continuous batch recirculation reaction system equipped with a parallel plate electrochemical cell. Selectivity and Faradic yields higher than 80% and 70%, respectively, were obtained by working under anhydrous conditions both under amperostatic and potentiostatic alimentation at appropriate values of either current density or applied potential.

  19. Mechanochemical Synthesis of TiO2 Nanocomposites as Photocatalysts for Benzyl Alcohol Photo-Oxidation

    Directory of Open Access Journals (Sweden)

    Weiyi Ouyang

    2016-05-01

    Full Text Available TiO2 (anatase phase has excellent photocatalytic performance and different methods have been reported to overcome its main limitation of high band gap energy. In this work, TiO2-magnetically-separable nanocomposites (MAGSNC photocatalysts with different TiO2 loading were synthesized using a simple one-pot mechanochemical method. Photocatalysts were characterized by a number of techniques and their photocatalytic activity was tested in the selective oxidation of benzyl alcohol to benzaldehyde. Extension of light absorption into the visible region was achieved upon titania incorporation. Results indicated that the photocatalytic activity increased with TiO2 loading on the catalysts, with moderate conversion (20% at high benzaldehyde selectivity (84% achieved for 5% TiO2-MAGSNC. These findings pointed out a potential strategy for the valorization of lignocellulosic-based biomass under visible light irradiation using designer photocatalytic nanomaterials.

  20. Development of Highly Effective Nanoparticle Spinel Catalysts for Aerobic Oxidation of Benzylic Alcoho1s

    Institute of Scientific and Technical Information of China (English)

    纪红兵; 王乐夫

    2002-01-01

    Spinel catalyst MnFe1.8Cu0.15Ru0.05O4 with partcle size of about 42nm is an effective heterogeneous catalyst for the oxidation of benzylic alcobols.The substitution of Fe for Cu improves its catalytic activity.Based on the characterization of BET,XPS and EXAFS,two factors influencing the structure and texture of the catalyst cauesd by the substitution of Cu for Fe may be assumed:physical factor responsible for the increasing of surface area;chemical factor responsible for the transformation of Ru-O bonds to Ru=O boods.β-Elimination is considered to be an important step in the reaction.

  1. Laparoscopic radical and partial cystectomy

    Directory of Open Access Journals (Sweden)

    Challacombe Ben

    2005-01-01

    Full Text Available Radical cystectomy remains the standard treatment for muscle invasive organ confined bladder carcinoma. Laparoscopic radical cystoprostatectomy (LRC is an advanced laparoscopic procedure that places significant demands on the patient and the surgeon alike. It is a prolonged procedure which includes several technical steps and requires highly developed laparoscopic skills including intra-corporeal suturing. Here we review the development of the technique, the indications, complications and outcomes. We also examine the potential benefits of robotic-assisted LRC and explore the indications and technique of laparoscopic partial cystectomy.

  2. Radical democratic politics and feminism

    Directory of Open Access Journals (Sweden)

    Martínez Labrin, Soledad

    2006-05-01

    Full Text Available In the article I present a reflection around the radical democratic project proposed by Chantal Mouffe and Ernesto Laclau. Specifically, I examine the application of the project in the context of the “new social movements” and especially, of feminist movement. I state the need of drawing attention to universalism and essentialism as the main obstacles to generate a collective proposal without margins. Nevertheless, doubts remind about the possibility of building up a feminism tailored by the radical democratic project, in a stage in which the political action of such a movement is characterized by categories that are closed and crystallized

  3. Quantification of a radical beam source for methyl radicals

    International Nuclear Information System (INIS)

    A radical beam source for methyl radicals (CH3) was characterized applying ionization-threshold mass spectrometry. The beam source is based on thermal dissociation of methane (CH4) or azomethane (N2(CH3)2) in a heated tungsten capillary. A flux of (3±1)x1013 cm-2 s-1 CH3 radicals is produced using methane as precursor gas and a capillary temperature of 1650 K. Alternatively, a flux of (3±1)x1014 cm-2 s-1 CH3 is produced using azomethane as precursor gas and a capillary temperature of 1150 K. The dominant production of methyl from the precursor methane occurs due to reaction 2 CH4+M→2 CH3+H2+M at the hot tungsten surface. The dominant production of methyl from azomethane occurs due to the reaction N2(CH3)2→2 CH3+N2. Besides methyl radicals, only stable molecules contribute to the emitted flux; within the detection limit, no atomic hydrogen is observed. From the comparison of ionization-threshold mass spectrometry and standard mass spectrometry, it is concluded that the cracking pattern of methane varies with the methane gas temperature. This is explained by the vibrational assisted dissociation of methane

  4. Benzyl alcohol oxidation in supercritical carbon dioxide: spectroscopic insight into phase behaviour and reaction mechanism.

    Science.gov (United States)

    Caravati, Matteo; Grunwaldt, Jan-Dierk; Baiker, Alfons

    2005-01-21

    Selective oxidation of benzyl alcohol to benzaldehyde with molecular oxygen over an alumina-supported palladium catalyst was performed with high rate at about 95% selectivity in supercritical carbon dioxide. The experiments in a continuous flow fixed-bed reactor showed that the pressure has a strong influence on the reaction rate. A marked increase of the rate (turnover frequency) from 900 h(-1) to 1800 h(-1) was observed when increasing the pressure from 140 to 150 bar. Video monitoring of the bulk fluid phase behavior and the simultaneous investigation by transmission and attenuated total reflection (ATR) infrared spectroscopy at two positions of the view cell showed that the sharp increase in activity is correlated to a transition from a biphasic to a monophasic reaction mixture. In the single phase region, both oxygen and benzyl alcohol are dissolved in the supercritical CO2 phase, which leads to a reduction of the mass transport resistances (both in the external fluid film and in the catalyst pores) and thus to the high reaction rate measured in the catalytic experiments. The phase transition could be effectively and easily monitored by transmission and ATR-IR spectroscopy despite the small concentration of the dense liquid like phase. Deposition of the Pd/Al2O3 catalyst on the ATR-crystal at the bottom of the view cell allowed to gain insight into the chemical changes and mass transfer processes occurring in the solid/liquid interface region during reaction. Analyzing the shift of the upsilon2 bending mode of CO2 gave information on the fluid composition in and outside the catalyst pores. Moreover, the catalytic reaction could be investigated in situ in this spectroscopic batch reactor cell by monitoring simultaneously the reaction progress, the phase behaviour and the catalytic interface. PMID:19785149

  5. Synthesis and Crystal Structure of 3-Phenyl-10b-benzyl-1,10b-dihydroimdazo[5,1-a]isoquinoline

    Institute of Scientific and Technical Information of China (English)

    HU,Xiang-Nan; JIN,Hong-Wei; YU,Yu; YAN,Shen-He

    2004-01-01

    @@ Praziquantel, 2-cyclohexylcarbonyl-1,2,3,6,7,11b-hexahydro-4H-pyrazino[2,1-a]isoquinolin-4-one, is a novel antiparasitic drug possessing one chiral center.[1] In the study of structure-activity relationship of praziquantel we were interested in its structural modification. 1-Benzyl Reissert compound of isoquinoline is required as starting materials for the synthesis of praziquantel analogues with modified chiral centers. On the other hand, we want to know what could be obtained when 1-benzyl Reissert compounds were exposed to high pressure catalytic hydrogenation. In this paper we report the results in the hydrogenation of 1-benzyl Reissert compound.

  6. Detecting Social Polarization and Radicalization

    DEFF Research Database (Denmark)

    Qureshi, Pir Abdul Rasool; Memon, Nasrullah; Wiil, Uffe Kock;

    2011-01-01

    This paper proposes a novel system to detect social polarization and to estimate the chances of violent radicalization associated with it. The required processes for such a system are indicated; it is also analyzed how existing technologies can be integrated into the proposed system to fulfill the...

  7. Exploring the Theories of Radicalization

    Directory of Open Access Journals (Sweden)

    Maskaliūnaitė Asta

    2015-12-01

    Full Text Available After the London bombings in July 2005, the concern of terrorism scholars and policy makers has turned to “home-grown” terrorism and potential for political violence from within the states. “Radicalization” became a new buzz word. This article follows a number of reviews of the literature on radicalization and offers another angle for looking at this research. First, it discusses the term “radicalization” and suggests the use of the following definition of radicalization as a process by which a person adopts belief systems which justify the use of violence to effect social change and comes to actively support as well as employ violent means for political purposes. Next, it proposes to see the theories of radicalization focusing on the individual and the two dimensions of his/her motivation: whether that motivation is internal or external and whether it is due to personal choice or either internal (due to some psychological traits or external compulsion. Though not all theories fall neatly within these categories, they make it possible to make comparisons of contributions from a variety of different areas thus reflecting on the interdisciplinary nature of the study of terrorism in general and radicalization as a part of it.

  8. Kinetics of nitroxyl radical reactions

    International Nuclear Information System (INIS)

    Absolute rate-constants for the reaction of the nitroxyl free radicals TAN and TMPN with radiation-chemically-formed radicals and ions have been determined. k(TAN + X) (in M-1 sec-1) = 4.0 x 109 (for X =OH), 2.9 x 1010(esub(aq)-), 8.0 x 109 (H), 7.2 x 108 (CH2OH), 4.0 x 108 (CH3CHOH), 4.3 x 108 ((CH3)2COH), 2.8 x 108 (CH2(CH3)2COH), 5.9 x 107 (glucose radical), 4.0 x 108 (c-C5H9), and k(TMPN + X) = 3.4 x 109 (OH), 7.8 x 109 (esub(aq)-), 4.9 x 109 (H), 4.4 x 108 (CH2OH), 4.9 x 108 (CH3CHOH), 3.6 x 108 ((CH3)2COH), 1.5 x 108 (CH2(CH3)2COH), 4.9 x 107 (glucose radical), 4.3 x 108 (c-C5H9). Direct measurements by means of a pulse-radiolysis conductivity technique were based on the formation and destruction of charged species in these reactions within certain pH ranges. It is indicated that the radiosensitizing nitroxyles undergo both redox and addition reactions. (author)

  9. Reaction between protein radicals and other biomolecules

    DEFF Research Database (Denmark)

    Østdal, Henrik; Davies, Michael Jonathan; Andersen, Henrik J

    2002-01-01

    The present study investigates the reactivity of bovine serum albumin (BSA) radicals towards different biomolecules (urate, linoleic acid, and a polypeptide, poly(Glu-Ala-Tyr)). The BSA radical was formed at room temperature through a direct protein-to-protein radical transfer from H(2)O(2....... Subsequent analysis showed a decrease in the concentration of urate upon reaction with the BSA radical, while the BSA radical in the presence of poly(Glu-Ala-Tyr) resulted in increased formation of the characteristic protein oxidation product, dityrosine. Reaction between the BSA radical and a linoleic acid...

  10. Functionalized polymer film surfaces via surface-initiated atom transfer radical polymerization

    International Nuclear Information System (INIS)

    The ability to manipulate and control the surface properties of polymer films, without altering the substrate properties, is crucial to their wide-spread applications. In this work, a simple one-step method for the direct immobilization of benzyl chloride groups (as the effective atom transfer radical polymerization (ATRP) initiators) on the polymer films was developed via benzophenone-induced coupling of 4-vinylbenzyl chloride (VBC). Polyethylene (PE) and nylon films were selected as examples of polymer films to illustrate the functionalization of film surfaces via surface-initiated ATRP. Functional polymer brushes of (2-dimethylamino)ethyl methacrylate, sodium 4-styrenesulfonate, 2-hydroxyethyl methacrylate and glycidyl methacrylate, as well as their block copolymer brushes, have been prepared via surface-initiated ATRP from the VBC-coupled PE or nylon film surfaces. With the development of a simple approach to the covalent immobilization of ATRP initiators on polymer film surfaces and the inherent versatility of surface-initiated ATRP, the surface functionality of polymer films can be precisely tailored. - Highlights: ► Atom transfer radical polymerization initiators were simply immobilized. ► Different functional polymer brushes were readily prepared. ► Their block copolymer brushes were also readily prepared

  11. From Radical Translation to Radical Interpretation and Back

    Directory of Open Access Journals (Sweden)

    António Zilhão

    2003-12-01

    Full Text Available Both Quine and Davidson put forth programs of empirical semantics satisfying the conditions that characterize the so-called “standpoint of interpretation.” Quine’s less ambitious program of radical translation rests upon two buttresses: causality and empathy. Davidson’s more ambitious program of radical interpretation replaces causality with truth and empathy with rationality. Although the replacement of causality with intersubjective truth seems to me to be a fully justified move, I nevertheless contend that it is more realistic to develop the work of interpretation drawing upon Quine’s less ambitious requirement of empathy than upon Davidson’s view of human agency as rational agency. In order to substantiate this contention, I present an argument to the effect that Davidson’s characterization of human agency as rational is not compatible with his other requirement that truth should pro-vide the essential link connecting speech with environment and action.

  12. A green and efficient oxidation of benzylic alcohols using H2O2 catalyzed by montmorillonite K-10 supported CoCl2

    Institute of Scientific and Technical Information of China (English)

    Ali Ezabadi; Ghloam Reza Najafi; Mohammad M.Hashemi

    2008-01-01

    Primary and secondary benzylic alcohols were oxidized to the corresponding carbonyl compounds in good to high yields by environmentally friendly and green oxidant,H2O2 catalyzed by montmorillonite K-10 supported cobalt(II) chloride.

  13. Electron attachment to fluorocarbon radicals

    Science.gov (United States)

    Shuman, Nicholas

    2014-10-01

    Most plasma environments contain populations of short-lived species such as radicals, the chemistry of which can have significant effects on the overall chemistry of the system. However, few experimental measurements of the kinetics of electron attachment to radicals exist due to the inherent difficulties of working with transient species. Calculations from first principles have been attempted, but are arduous and, because electron attachment is so sensitive to the specifics of the potential surface, their accuracy has not been established. Electron attachment to small fluorocarbon radicals is particularly important, as the data are needed for predictive modeling of plasma etching of semiconductor materials, a key process in the industrial fabrication of microelectronics. We have recently developed a novel flowing afterglow technique to measure several types of otherwise difficult to study plasma processes, including thermal electron attachment to radicals. Variable Electron and Neutral Density Attachment Mass Spectrometry (VENDAMS) exploits dissociative electron attachment in a weakly ionized plasma as a radical source. Here, we apply VENDAMS to a series of halofluorocarbon precursors in order to measure the kinetics of thermal electron attachment to fluorocarbon radicals. Results are presented for CF2, CF3, C2F5,C2F3,1-C3F7, 2-C3F7, and C3F5 from 300 K to 900 K. Both the magnitude and the temperature dependences of rate coefficients as well as product branching between associative and dissociative attachment are highly system specific; however, thermal attachment to all species is inefficient, never exceeding 5% of the collision rate. The data are analyzed using a recently developed kinetic modeling approach, which uses extended Vogt-Wannier theory as a starting point, accounts for dynamic effects such as coupling between the electron and nuclear motions through empirically validated functional forms, and finally uses statistical theory to determine the fate of

  14. The Stabilized Cation Pool Method: Metal- and Oxidant-Free Benzylic C-H/Aromatic C-H Cross-Coupling.

    Science.gov (United States)

    Hayashi, Ryutaro; Shimizu, Akihiro; Yoshida, Jun-Ichi

    2016-07-13

    Electrochemical oxidation of toluene derivatives in the presence of a sulfilimine gave benzylaminosulfonium ions as stabilized benzyl cation pools, which reacted with subsequently added aromatic nucleophiles to give the corresponding cross-coupling products. The transformation serves as a powerful metal- and chemical-oxidant-free method for benzylic C-H/aromatic C-H cross-coupling. The method has been successfully applied to synthesis of TP27, an inhibitor of PTPase. PMID:27341676

  15. In vitro and in vivo pharmacological profile of the 5-benzyl analogue of 14-methoxymetopon, a novel μ opioid analgesic with reduced propensity to alter motor function

    OpenAIRE

    Spetea, Mariana; Bohotin, Catalina R.; Asim, Muhammad F; Stübegger, Kurt; Schmidhammer, Helmut

    2010-01-01

    Opioids are the most effective analgesics for pain management, and efficient pain control is a therapeutic priority. Herein, we describe the synthesis and pharmacological activities of the 5-benzyl analogue of the μ opioid analgesic 14-methoxymetopon (14-MM). The result of the replacement of the 5-methyl in 14-MM with a benzyl group on in vitro opioid receptor binding and functional profiles, and in vivo behavioural properties, i.e. nociception and motor activity, was investigated. In rodent ...

  16. PPA-SiO2 Catalyzed Multi-component Synthesis of N-[α-(β-Hydroxy-α-naphthyl)(benzyl)]O-Alkyl Carbamate Derivatives

    Institute of Scientific and Technical Information of China (English)

    SHATERIAN,Hamid Reza; HOSSEINIAN,Asghar; GHASHANG,Majid

    2009-01-01

    Silica-supported polyphosphoric acid (PPA-SiO2) was found to be an efficient catalyst for the multi-component condensation reaction of benzaldehydes,2-naphthol,and methyl/benzyl carbamate to afford the corresponding N-[α-(β-hydroxy-α-naphthyl)(benzyl)]O-alkyl carbamate derivatives in good to excellent yields.This new approach consistently has the advantage of short reaction time,high conversions,clean reaction profiles,and simple experimental and work-up procedures.

  17. 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.

  18. EPR spin trapping of protein radicals

    DEFF Research Database (Denmark)

    Davies, Michael Jonathan; Hawkins, Clare L

    2004-01-01

    Electron paramagnetic resonance (EPR) spin trapping was originally developed to aid the detection of low-molecular-mass radicals formed in chemical systems. It has subsequently found widespread use in biology and medicine for the direct detection of radical species formed during oxidative stress...... selected examples of radical formation on proteins....

  19. Synthesis and characterization of a novel amphiphilic biodegradable β-cyclodextrin/poly(γ-benzyl L-glutamate) copolymer

    Institute of Scientific and Technical Information of China (English)

    Qiu Hua Wu; Fang Liang; Tian Zhu Wei; Xi Ming Song; Shu Yao Wu; Guo Lin Zhang

    2009-01-01

    β-Cyclodextrin/poly(γ-benzyl L-glutamate) (β-CD-PBLG) copolymers were synthesized by ring-opening polymerization of N-carboxy-γ-benzyl L-glutamate anhydride (BLG-NCA) in N,N-dimethylformamide (DMF) initiated by mono-amino-β-cyclodex-trin(H2N-β-CD). The structures of the copolymers were confirmed by IR, 1H NMR and GPC. The fluorescence technique was used to determine the critical micelle concentrations (CMC) of copolymer miceU solution, the diameter and the distribution of micelles were characterized by DLS. The results showed that BLG-NCA could be initiated by H2N-β-CD to produce copolymer. The nano-micells were formed by these copolymers in water.

  20. A green four-component synthesis of zwitterionic alkyl/benzyl pyrazolyl barbiturates and their photophysical studies.

    Science.gov (United States)

    Bihani, Manisha; Bora, Pranjal P; Bez, Ghanashyam; Askari, Hassan

    2014-11-01

    A novel series of unsymmetrically substituted alkyl/benzyl pyrazolyl barbiturates incorporating highly biologically active pyrazolone and barbiturate moieties was synthesized by four-component reactions of a mixture of ethyl acetoacetate, hydrazine hydrate, aldehydes and barbituric acid/thiobarbituric acid in ethanol without using a catalyst. The photophysical properties of the newly designed alkyl/benzyl pyrazolyl barbiturates were studied, and good quantum yield of some products indicated a definitive scope in the field of biochemical applications. Single-crystal X-ray crystallographic studies revealed that the newly synthesized compounds exist in zwitterionic form. The zwitterionic nature of the new chimera makes them interesting candidates for drug delivery as zwitterionic drugs are known to have highly water soluble properties, specific protein absorption, slow recognition by immune system, slow blood clearance from body and can constantly diffuse and deposit throughout the physiological pH. PMID:25005075

  1. (1S,3S,4S-tert-Butyl N-[1-benzyl-3-hydroxy-5-phenyl-4-(picolinamidopentyl]carbamate

    Directory of Open Access Journals (Sweden)

    Jian-Feng Zheng

    2008-07-01

    Full Text Available The title compound, C29H35N3O4, was obtained by the reaction of (2S,4S,5S-tert-butyl N-(4-amino-1-benzyl-3-hydroxy-5-phenylpentylcarbamate and picolinic acid using oxalyl chloride as a chlorinating reagent to activate the carboxyl group. In the crystal structure there are two molecules in the asymmetric unit, which are aligned edge-to-face. In one molecule, the pyridyl ring forms a dihedral angle of 22.0 (1° with the phenyl ring of the terminal benzyl group and 14.3 (1° with the other phenyl ring; in the other molecule, the corresponding angles are 12.1 (1 and 10.6 (1°, respectively. The packing is stabilized by intermolecular hydrogen bonds and C—H...π interactions.

  2. Two New Saccharide Fatty Acid Esters from the Fruit of Morinda citrifolia L. and Their ABTS Radical Scavenging Activities

    Directory of Open Access Journals (Sweden)

    Hong-Cai Zhang

    2013-11-01

    Full Text Available Two n ew saccharide fatty acid esters (1 and (2, and six other compounds were isolated from the fruit of Morinda citrifolia L. (Rubiaceae The structures were established as (2E-oct-2-enoate-2-O-β-D - glucopyranosyl-β-D-glucopyranoside(1, (2E-2,6-dimethyl -6-hydroxyl-oct-2,7-dienoate-2-O-β-D-glucopyranosyl-β-D-glucopyranoside(2, saccharumoside C(3, O-β-D-apiofuranosyl-(1→6-O-β-D-glucopyranosides of 3-methyl-2-butenol(4, 3-methyl-but-2-en-1-yl β-D-glucopyranosyl (1→6-β-D-glucopyranoside(5, benzyl - glucopyranoside(6, Hexyl-O-β-D-glucopyranoside(7, and caproic acid(8. Compound 1 and 2 showed moderate activity against ABTS (2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonate radical in concentration of 0.1-3.2 mg/mL.

  3. Free radicals and Dupuytren's contracture.

    OpenAIRE

    Murrell, G. A.; Francis, M. J.; Bromley, L.

    1987-01-01

    The concentration of substrate expressed as hypoxanthine capable of reacting with xanthine oxidase to release superoxide free radicals (O2-) was measured in control and Dupuytren's contracture palmar fascia. In Dupuytren's contracture palmar fascia the concentration of hypoxanthine was six times that of control and was greatest in "nodular" areas. Xanthine oxidase activity was also detected in Dupuytren's contracture palmar fascia. These results suggest a greater potential for hypoxanthine-xa...

  4. Skin oxygenation after topical application of liposome-entrapped benzyl nicotinate as measured by EPR oximetry in vivo

    OpenAIRE

    Abramović, Zrinka; Šentjurc, Marjeta; Kristl, Julijana

    2015-01-01

    New and improved drug delivery systems are the important subject of much scientific research. The development of formulations that increase skin oxygenation and of methods for measuring oxygen levels in skin are important for dealing with healing processes affected by the level of oxygen. We have used EPR oximetry in vivo to compare the influence of liposomal formulations of different size and composition with that of hydrogel with respect to the action of the entrapped benzyl nicotinate (BN)...

  5. Plasmonic Au/CdMoO4 photocatalyst: Influence of surface plasmon resonance for selective photocatalytic oxidation of benzylic alcohol

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • Au/CdMoO4 composites were constructed for the first time. • Au/CdMoO4 showed superior activity for selective oxidation of benzylic alcohol. • The visible light photocatalytic activity is ascribed to the SPR effect of Au. - Abstract: Novel visible-light-driven plasmonic Au/CdMoO4 photocatalysts were synthesized by hydrothermal process following chemical reduction process. The catalysts were characterized by X-ray diffraction, transmission electron microscopy, UV–vis diffuse reflectance spectroscopy and X-ray photoelectron spectroscopy. The results show the catalysts exhibited strong visible light absorption due to the surface plasmon resonance effect of Au nanoparticles. Compared to CdMoO4, Au/CdMoO4 composites displayed superior photocatalytic activities for the selective oxidation of benzylic alcohol to benzaldehyde under visible light. The highest conversion was obtain by the 1.6% Au loaded CdMoO4. The mechanism for the selective oxidation of benzylic alcohol in the Au/CdMoO4 system is proposed

  6. Evaluation of antibacterial activity of 3-butenyl, 4-pentenyl, 2-phenylethyl, and benzyl isothiocyanate in Brassica vegetables.

    Science.gov (United States)

    Jang, Miran; Hong, Eunyoung; Kim, Gun-Hee

    2010-09-01

    This study investigated antibacterial activities of 4 isothiocyanates (3-butenyl, 4-phentenyl, 2-phenylethyl, and benzyl isothiocyanate) against 4 Gram-positive bacteria (Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, and Staphylococcus aureus) and 7 Gram-negative bacteria (Aeromonas hydrophila, Pseudomonas aeruginosa, Salmonella choleaesuis, Salmonella enterica, Serratia marcescens, Shigella sonnei, and Vibrio parahaemolyticus) by an agar disc diffusion assay. Benzyl isothiocyanate (> 90.00 mm inhibition zone diameter at 0.1 μL/mL) and 2-phenylethyl isothiocyanate (58.33 mm at 0.2 μL/mL) showed large inhibition zones especially against B. cereus. Also, 3-butenyl isothiocyanate (21.67 mm at 1.0 μL/mL) and 4-pentenyl isothiocyanate (19.67 mm at 1.0 μL/mL) displayed potent antibacterial activity against A. hydrophila. Benzyl and 2-phenylethyl isothiocyanate indicated higher activity against most of the pathogenic bacteria than 3-butenyl and 4-pentenyl isothiocyanate, and were more effective against Gram-positive bacteria than Gram-negative bacteria. PMID:21535549

  7. Synthesis, stereochemistry and antimicrobial evaluation of t(3)-benzyl-r(2),c(6)-diarylpiperidin-4-one and its derivatives.

    Science.gov (United States)

    Jayabharathi, J; Manimekalai, A; Consalata Vani, T; Padmavathy, M

    2007-05-01

    In a wide research program toward new and efficient antimicrobial agents, a series of t(3)-benzyl-r(2),c(6)-diarylpiperidin-4-ones (1-7) were synthesised and tested for their in vitro antibacterial and antifungal activities. Also, the structures and their stereochemistry of these synthesised compounds 1-7 were characterized by IR, high resolution (1)H NMR, (13)C NMR and (1)H-(13)C COSY spectra. The analysis of coupling constants of compounds 1-5 reveals that they exist in normal chair conformation with equatorial orientations of all the substituents. The spectra of 6 and 7 reveal the presence of two isomers labeled as E (carbonyl carbon is anti to benzyl group at C-3) and Z (carbonyl carbon is syn to benzyl group at C-3) in solution and the coupling constants ruled out the possibility of normal chair conformation. From the theoretical studies and coupling constant values the favoured conformation for the Z- and E-isomers of 6 and 7 was found to be the boat conformations. Their antibacterial activity against Streptococcus faecalis, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae and antifungal activity against Cryptococcus neoformans, Candida 6, Candida 51, Aspergillus niger and Aspergillus flavus were also evaluated. PMID:17241703

  8. Fe3+-Exchanged Titanate Nanotubes: A New Kind of Highly Active Heterogeneous Catalyst for Friedel-Crafts Type Benzylation

    Directory of Open Access Journals (Sweden)

    Yunchen Du

    2015-01-01

    Full Text Available Heterogeneous catalysis for Friedel-Crafts type benzylation has received much attention in recent years due to its characteristic of environmental benefits. In this paper, titanate nanotubes (TNTs were employed as heterogeneous catalyst support, and a new kind of Fe3+-exchanged titanate nanotubes (Fe-TNTs catalyst with highly dispersed ferric sites was constructed by an ion exchange technique. The obtained catalyst was systematically characterized by XRD, TEM, N2 adsorption, XPS, and UV-vis spectra. As expected, Fe-TNTs showed excellent catalytic activities in the benzylation of benzene and benzene derivatives. The recycling tests for Fe-TNTs were also carried out, where the reason for the gradually decreased activity was carefully investigated. Superior to some reported catalysts, the catalytic ability of used Fe-TNTs could be easily recovered by ion exchange again, indicating that Fe-TNTs herein were a highly active and durable heterogeneous catalyst for Friedel-Crafts type benzylation. These results might be helpful for the design and preparation of novel heterogeneous catalysts by combining the structural advantages of titanate nanotubes and active metal ions.

  9. Chemical repair of trypsin-histidinyl radical

    International Nuclear Information System (INIS)

    Oxyl radicals, such as hydroxyl, alkoxyl and peroxyl, react with biomolecules to produce bioradicals. Unless chemically repaired by suitable antioxidants, these bioradicals form stable products. This leads to loss of biological function of parent biomolecules with deleterious biological results, such as mutagenesis and cancer. Consequently, the understanding of the mechanisms of oxyl radical damage to biomolecules and chemical repair of such damage is crucial for the development of strategies for anticarcinogenesis and radioprotection. In this study the chemical repair of the histidinyl radical generated upon the trichloromethylperoxyl radical reaction with trypsin vas investigated by gamma radiolysis. The trypsin histidinyl radical is a resonance-stabilized heterocyclic free radical which was found to be unreactive with oxygen. The efficacy of the chemical repair of the trypsin-histidinyl radical by endogenous antioxidants which are electron donors (e.g. 5-hydroxytryptophan, uric acid) is compared to that of antioxidants which are H-atom donors (e. g. glutathione). 9 refs., 2 figs., 1 tab

  10. Tuning the Solubility of Copper Complex in Atom Transfer Radical Self-Condensing Vinyl Polymerizations to Control Polymer Topology via One-Pot to the Synthesis of Hyperbranched Core Star Polymers

    OpenAIRE

    Zong-Cheng Chen; Chia-Ling Chiu; Chih-Feng Huang

    2014-01-01

    In this paper, we propose a simple one-pot methodology for proceeding from atom transfer reaction-induced conventional free radical polymerization (AT-FRP) to atom transfer self-condensing vinyl polymerization (AT-SCVP) through manipulation of the catalyst phase homogeneity (i.e., CuBr/2,2'-bipyridine (CuBr/Bpy)) in a mixture of styrene (St), 4-vinyl benzyl chloride (VBC), and ethyl 2-bromoisobutyrate. Tests of the solubilities of CuBr/Bpy and CuBr2/Bpy under various conditions revealed that ...

  11. Effect of Isotacticity of Linear Poly(N-isopropylacrylamide) on its Gelation in Benzyl Alcohol

    Indian Academy of Sciences (India)

    CHANDRA SEKHAR BISWAS; KHEYANATH MITRA; SHIKHA SINGH; DINESH K PATEL; BISWAJIT MAITI; PRALAY MAITI; BISWAJIT RAY

    2016-06-01

    Thermoreversible gelation of three different isotactic linear poly(N-isopropylacrylamide) (PNIPAM)s having meso dyad (m) values 62, 68 and 81% has been observed in benzyl alcohol. All the gels weretransparent in nature. SEM image of the dried gels showed fibrillar network morphology. Melting temperatureof the gels gradually increased with the increase in the concentration. XRD data of dry polymers and their correspondingdry gels showed shifting in the peak positions. Rheological study showed that stronger gels wereformed with increasing isotacticity of PNIPAM while lower isotactic sample exhibited typical polymer meltrheology. The formation of a plunge in the storage modulus as well as in the viscosity plot at the same frequencyrange indicates the reversible nature of the structure breaking/reformation under frequency sweep. Moreover,the mechanical strength of the gel decreased with increase in temperature. UV-Vis kinetic study also indicatedthe change in the conformation and aggregation of PNIPAM chains during gelation. Molecular modelling calculationshowed that the number of solvent molecules involved in forming gel (polymer-solvent compound)decreased with the increase in the isotacticity of the polymer. Gelation rate of these gels was studied as a functionof temperature, concentration and isotacticity using test-tube tilting method. It increased with the increasein the concentration and isoacticity of the polymer, and with the decrease in the temperature. Critical gelationconcentration of the gel gradually increased with the decrease in the isotacticity and with the increase in thetemperature. All these experimental results indicated that gelation occurs presumably through polymer-solventcompound formation.

  12. Pertumbuhan Plantlet Anggrek Cattleya sp. dengan Perlakuan Benzyl Amino Purine pada Media Dasar Pupuk Daun Modifikasi

    Directory of Open Access Journals (Sweden)

    HESTIN YUSWANTI

    2015-09-01

    Full Text Available Growth of Plantlets of Cattleya Orchid on The Fooliar Fertilizer-Based Medium added with Benzyl Amino Purine. The aim of the current research was to investigate the appropriate concentrationof plant growth regulator BAP on the growth of Cattleya plantlet. The experiment was utilized a Randomized Completely Design with five treatments and six replications. The basal medium used was modification of foliar fertilizer of Growmore (trade mark with addition of fish emulsion, Vitamin B1 and active charcoal. BAP concentration used as treatment were 0 ppm, 0.5 ppm, 1.0 ppm, 1.5 ppm and 2.0 ppm. Variables observed were height, leaf number, root number, root length, fresh weight and dry weight of plantlets. The result showed that concentration of 1 ppm BAP resulted in the highest value for plantlet height (5.67 cm, leaf number (4.67, root length (2.07 cm, fresh weight (0.36 g and dry weight (0.043 g.

  13. Benzyl butyl phthalate induces epigenetic stress to enhance adipogenesis in mesenchymal stem cells.

    Science.gov (United States)

    Sonkar, Ravi; Powell, Catherine A; Choudhury, Mahua

    2016-08-15

    Endocrine disruptors, phthalates, may have contributed to recent global obesity health crisis. Our study investigated the potential of benzyl butyl phthalate (BBP) to regulate the mesenchymal stem cell epigenome to drive adipogenesis. BBP exposure enhanced lipid accumulation and adipogenesis in a dose-dependent manner compared to control (P < 0.001). Adipogenesis markers, PPARγ (P < 0.001), C/EBPα (P < 0.01), and aP2 (P < 0.001) were significantly upregulated by increasing concentrations of BBP when compared to DMSO. BBP enhanced H3K9 acetylation while decreasing H3K9 dimethylation. Fifty μM BBP increased histone acetyltransferases, p300 (P < 0.05) and GCN5 (P < 0.01) gene expression. Furthermore, histone deacetylases (HDACs), HDAC3 (P < 0.01) and HDAC10 (P < 0.01, 10 μM BBP; P < 0.001, 50 μM BBP) and histone methyltransferases, SETDB1 (P < 0.01) and G9a (P < 0.01), were significantly downregulated by BBP exposure. BBP acts, in part, through PPARγ, as PPARγ knockdown led to decreased H3K9ac and rescued H3K9me2 during BBP exposure. In conclusion, BBP regulated MSCs towards adipogenesis by tipping the epigenomic balance. PMID:27164441

  14. Facile solvothermal synthesis of NIR absorbing CsxWO3 nanorods by benzyl alcohol route

    International Nuclear Information System (INIS)

    Near infrared absorbing CsxWO3 nanoparticles with uniform particle size distribution were synthesized in two hours by solvothermal method. Benzyl alcohol was used as a main solvent and a reactant to facilitate a controlled reaction and stabilization in the presence of oleic acid as a capping agent. Different reaction conditions such as reaction time, reaction temperature, and oleic acid amount were studied and reported. Hexagonal CsxWO3 nanorods with average size of 80 nm were obtained in 2 h reaction time, at 240 °C reaction temperature, and 10% vol. oleic acid. Aqueous dispersion of the nanorods showed high transparency (about 80–90%) in visible light with strong near infrared (NIR) light shielding (80–90%). This indicates that CsxWO3 is an attractive material to employ in heat-shielding transparent coatings for windows of buildings and automobiles. Using this simple process, it is possible to synthesize homogenous CsxWO3 nanorods with low temperature and short reaction time. Moreover, the process offers an opportunity for large-scale synthesis of NIR absorbing nanorods. (paper)

  15. A new multifunctional, shine-enhancing emollient: PPG-3 benzyl ether myristate.

    Science.gov (United States)

    Gao, Timothy; Pereira, Abel; Obukowho, Patrick

    2004-01-01

    A new emollient ester--Crodamol STS (INCI name: PPG-3 Benzyl Ether Myristate) has been developed and characterized. This special non-volatile emollient is safe to use and provides silicone-like feel and multiple cosmetic functionality. It is a liquid with a viscosity about 100 cps at room temperature. It has a high refractive index--1.4696, which enhances hair shine, contributes to high gloss in lip products, and reduces whitening effect of fatty alcohols and silica in anti-perspirants/deodorants applications. This emollient has high solubility of UV filters, low skin-spreading factor, and good pigment wetting behavior, which are preferable in sunscreen and make-up formulas to enhance the pigment localization and improve SPF value. In this paper, the chemical structure, physical properties, and various cosmetic applications of the emollient will be discussed. Especially, an objective hair shine (luster) test method (color image analysis) has been established and applied to study the enhancement in hair shine by Crodamol STS in hair spray and hair gel formulations. The objective measurements in hair shine showed good agreement with the results obtained from subjective evaluations. The substantivity of Crodamol STS on hair surface, which was delivered from a rinse-off cream, was also determined by a solvent extraction method. PMID:15645090

  16. Glucuronoyl Esterase Screening and Characterization Assays Utilizing Commercially Available Benzyl Glucuronic Acid Ester

    Directory of Open Access Journals (Sweden)

    Hampus Sunner

    2015-09-01

    Full Text Available Research on glucuronoyl esterases (GEs has been hampered by the lack of enzyme assays based on easily obtainable substrates. While benzyl d-glucuronic acid ester (BnGlcA is a commercially available substrate that can be used for GE assays, several considerations regarding substrate instability, limited solubility and low apparent affinities should be made. In this work we discuss the factors that are important when using BnGlcA for assaying GE activity and show how these can be applied when designing BnGlcA-based GE assays for different applications: a thin-layer chromatography assay for qualitative activity detection, a coupled-enzyme spectrophotometric assay that can be used for high-throughput screening or general activity determinations and a HPLC-based detection method allowing kinetic determinations. The three-level experimental procedure not merely facilitates routine, fast and simple biochemical characterizations but it can also give rise to the discovery of different GEs through an extensive screening of heterologous Genomic and Metagenomic expression libraries.

  17. Isolation and identification of 4-α-rhamnosyloxy benzyl glucosinolate in Noccaea caerulescens showing intraspecific variation.

    Science.gov (United States)

    de Graaf, Rob M; Krosse, Sebastian; Swolfs, Ad E M; te Brinke, Esra; Prill, Nadine; Leimu, Roosa; van Galen, Peter M; Wang, Yanli; Aarts, Mark G M; van Dam, Nicole M

    2015-02-01

    Glucosinolates are secondary plant compounds typically found in members of the Brassicaceae and a few other plant families. Usually each plant species contains a specific subset of the ∼ 130 different glucosinolates identified to date. However, intraspecific variation in glucosinolate profiles is commonly found. Sinalbin (4-hydroxybenzyl glucosinolate) so far has been identified as the main glucosinolate of the heavy metal accumulating plant species Noccaea caerulescens (Brassicaceae). However, a screening of 13 N. caerulescens populations revealed that in 10 populations a structurally related glucosinolate was found as the major component. Based on nuclear magnetic resonance (NMR) and mass spectrometry analyses of the intact glucosinolate as well as of the products formed after enzymatic conversion by sulfatase or myrosinase, this compound was identified as 4-α-rhamnosyloxy benzyl glucosinolate (glucomoringin). So far, glucomoringin had only been reported as the main glucosinolate of Moringa spp. (Moringaceae) which are tropical tree species. There was no apparent relation between the level of soil pollution at the location of origin, and the presence of glucomoringin. The isothiocyanate that is formed after conversion of glucomoringin is a potent antimicrobial and antitumor agent. It has yet to be established whether glucomoringin or its breakdown product have an added benefit to the plant in its natural habitat. PMID:25482220

  18. Effect of benzyl butyl phthalate on physiology and proteome characterization of water celery (Ipomoea aquatica Forsk.).

    Science.gov (United States)

    Chen, Wen-Ching; Huang, Han-Ching; Wang, Yei-Shung; Yen, Jui-Hung

    2011-07-01

    This study examined the effect of benzyl butyl phthalate (BBP), a phthalate ester (PAE) and an endocrine disruptor, on water celery, Ipomoea aquatica Forsk., one of the most popular leaf vegetables in Taiwan. After 28 days of cultivation, treatment with 100 mgL⁻¹ BBP retarded plant growth and decreased biomass and number of mature leaves and caused the accumulation of proline in leaves of water celery, but the concentrations of chlorophyll a and b in the leaves remained constant. 2-D gel electrophoresis and matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis of the proteome of leaf tissue revealed five protein spots with up- and down-regulated expression. The predicted protein XP_001417439 was down-regulated, which explained inhibition of plant growth, and the proteina XP_001417040, calreticulin, GAI-like protein 1, and (-)-linalool synthase were up-regulated, which indicates interference with the cell cycle and protein synthesis, as well as dwarfism of water celery. BBP is a stressor on the growth of water celery, and proteome analysis revealed the up- and down-regulation of genes involved in plant growth with BBP treatment. PMID:21496923

  19. Preparation and physico-chemical study of nitroxide radicals. Isotopic marking with carbon 13 and deuterium

    International Nuclear Information System (INIS)

    N-t-butyl-N-phenyl nitroxide is obtained by: a) action of t-butyl-magnesium chloride on nitrobenzene, or of phenyl-magnesium bromide on nitro-t-butane, b) oxidation of N-t-butyl-N-phenylhydroxylamine, c) oxidation of N-t-butylaniline. In these latter two cases, it has been possible to isolate the pure radical and to study it using UV, IR and EPR. It decomposes to give N-t-butylaniline and the N-oxide of N-t-butyl-p-quinon-imine. The action of peracids such as p-nitro-perbenzoic or m-chloro-perbenzoic acids on amines or hydroxylamines leads to the formation of stable or unstable nitroxide radicals easily observable by EPR. Finally, with a view to obtaining definite values for the coupling between the free electron of a nitroxide and carbon 13, the preparation of such radicals marked with 13C in the α or β position of the nitroxide function has been carried out. The coupling with an α carbon 13 is negative and does not appear to vary with the spin density on the nitrogen. The interaction with the p nuclei of the nitrogen depends on the nature of the substituents: the two benzyl protons have a hyperfine splitting aH which is always less than that of the ethyl. On the other hand, the 13C coupling is greater in the first case. The usually adopted conformations for the compounds having the carbonyl group cannot account for the observed values of the β couplings. (author)

  20. Iron and iron derived radicals

    International Nuclear Information System (INIS)

    We have discussed some reactions of iron and iron-derived oxygen radicals that may be important in the production or treatment of tissue injury. Our conclusions challenge, to some extent, the usual lines of thought in this field of research. Insofar as they are born out by subsequent developments, the lessons they teach are two: Think fast! Think small! In other words, think of the many fast reactions that can rapidly alter the production and fate of highly reactive intermediates, and when considering the impact of competitive reactions on such species, think how they affect the microenvironment (on the molecular scale) ''seen'' by each reactive molecule. 21 refs., 3 figs., 1 tab

  1. Aromatic-radical oxidation chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Glassman, I.; Brezinsky, K. [Princeton Univ., NJ (United States)

    1993-12-01

    The research effort has focussed on discovering an explanation for the anomalously high CO{sub 2} concentrations observed early in the reaction sequence of the oxidation of cyclopentadiene. To explain this observation, a number of plausible mechanisms have been developed which now await experimental verification. One experimental technique for verifying mechanisms is to probe the reacting system by perturbing the radical concentrations. Two forms of chemical perturbation of the oxidation of cyclopentadiene were begun during this past year--the addition of NO{sub 2} and CO to the reacting mixture.

  2. Laser spectroscopy of hydrocarbon radicals

    Energy Technology Data Exchange (ETDEWEB)

    Chen, P. [Harvard Univ., Cambridge, MA (United States)

    1993-12-01

    The author reports the application of supersonic jet flash pyrolysis to the specific preparation of a range of organic radicals, biradicals, and carbenes in a skimmed molecular beam. Each species was produced cleanly and specifically, with little or no secondary reactions by the thermal dissociation of appropriately designed and synthesized organic precursors. Photoelectron spectra of the three isomeric C{sub 3}H{sub 2} carbenes, ortho-benzyne, and the {alpha},3-dehydrotoluene biradical, were used to establish adiabatic ionization potentials for use in thermochemical determinations.

  3. 18O isotope effect in 13C nuclear magnetic resonance spectroscopy. Part 9. Hydrolysis of benzyl phosphate by phosphatase enzymes and in acidic aqueous solutions

    International Nuclear Information System (INIS)

    The 18O isotope-induced shifts in 13C and 31P nuclear magnetic resonance (NMR) spectroscopy were used to establish the position of bond cleavage in the phosphatase-catalyzed and acid-catalyzed hydrolysis reactions of benzyl phosphate. The application of the 18O-isotope effect in NMR spectroscopy affords a continuous, nondestructive assay method for following the kinetics and position of bond cleavage in the hydrolytic process. The technique provides advantages over most discontinuous methods in which the reaction components must be isolated and converted to volatile derivatives prior to analysis. In the present study, [α-13C,ester-18O]benzyl phosphate and [ester-18O]benzyl phosphate were synthesized for use in enzymatic and nonenzymatic studies. Hydrolysis reactions catalyzed by the alkaline phosphatase from E. coli and by the acid phosphatases isolated from human prostate and human liver were all accompanied by cleavage of the substrate phosphorus-oxygen bond consistent with previously postulated mechanisms involving covalent phosphoenzyme intermediates. An extensive study of the acid-catalyzed hydrolysis of benzyl phosphate at 750C revealed that the site of bond cleavage is dependent on pH. At pH less than or equal to 1.3, the hydrolysis proceeds with C-O bond cleavage; at 1.3 2H]Benzyl phosphate was also synthesized. Hydrolysis of this chiral benzyl derivative demonstrated that the acid-catalyzed C-O bond scission of benzyl phosphate proceeds by an A-1 (S/sub N/1) mechanism with 70% racemization and 30% inversion at carbon. 37 references, 4 figures, 2 tables

  4. Detection of a secondary muoniated radical

    Energy Technology Data Exchange (ETDEWEB)

    McCollum, Brett M.; Brodovitch, Jean-Claude [TRIUMF and Department of Chemistry, Simon Fraser University, Burnaby, BC, V5A 1S6 (Canada); Clyburne, Jason A.C. [Department of Chemistry, Saint Mary' s University, Halifax, NS, B3H 3C3 (Canada); Percival, Paul W., E-mail: percival@sfu.c [TRIUMF and Department of Chemistry, Simon Fraser University, Burnaby, BC, V5A 1S6 (Canada); West, Robert [Organosilicon Research Center, University of Wisconsin, Madison, WI 53706 (United States)

    2009-04-15

    Muoniated free radicals are formed by addition of muonium to unsaturated molecules. Successful detection by transverse-field muon spin rotation (muSR) usually requires pure or highly concentrated samples and a muonium reaction rate in excess of 10{sup 9} M{sup -1}s{sup -1} to ensure that the muon spin polarization is coherently transferred to the radical. For this reason muoniated radicals reported to date are all the primary radical products of Mu reaction. Thus, it was expected that Mu addition to a silylene would result in detection of a silyl radical. However, the muon hyperfine constant determined by experiment is much smaller than the value predicted by density functional calculations. Instead, it is consistent with a disilanyl radical, the secondary radical formed by reaction of the initially formed silyl radical with a second silylene molecule. From an analysis of the signal amplitude it was deduced that the second-order rate constant for reaction of the muoniated silyl radical with the parent silylene is 5.7x10{sup 8} M{sup -1}s{sup -1}. This work represents the first example of direct detection of a secondary radical product by transverse-field muSR.

  5. Short-form RON overexpression augments benzyl isothiocyanate-induced apoptosis in human breast cancer cells.

    Science.gov (United States)

    Sehrawat, Anuradha; Singh, Shivendra V

    2016-05-01

    Chemoprevention of breast cancer is feasible with the use of non-toxic phytochemicals from edible and medicinal plants. Benzyl isothiocyanate (BITC) is one such plant compound that prevents mammary cancer development in a transgenic mouse model in association with tumor cell apoptosis. Prior studies from our laboratory have demonstrated a role for reactive oxygen species (ROS)-dependent Bax activation through the intermediary of c-Jun N-terminal kinases in BITC-induced apoptosis in human breast cancer cells. The present study demonstrates that truncated Recepteur d'Origine Nantais (sfRON) is a novel regulator of BITC-induced apoptosis in breast cancer cells. Overexpression of sfRON in MCF-7 and MDA-MB-361 cells resulted in augmentation of BITC-induced apoptosis when the apoptotic fraction was normalized against vehicle control for each cell type (untransfected and sfRON overexpressing cells). ROS generation and G2 /M phase cell cycle arrest resulting from BITC treatment were significantly attenuated in sfRON overexpressing cells after normalization with vehicle control for each cell type. Increased BITC-induced apoptosis by sfRON overexpression was independent of c-Jun N-terminal kinase or p38 mitogen-activated protein kinase hyperphosphorylation. On the other hand, activation of Bax and Bak following BITC exposure was markedly more pronounced in sfRON overexpressing cells than in controls. sfRON overexpression also augmented apoptosis induction by structurally diverse cancer chemopreventive phytochemicals including withaferin A, phenethyl isothiocyanate, and D,L-sulforaphane. In conclusion, the present study provides novel mechanistic insights into the role of sfRON in apoptosis regulation by BITC and other electrophilic phytochemicals. © 2015 Wiley Periodicals, Inc. PMID:25857724

  6. Benzyl isothiocyanate inhibits inflammasome activation in E. coli LPS-stimulated BV2 cells.

    Science.gov (United States)

    Lee, Chang-Min; Lee, Dae-Sung; Jung, Won-Kyo; Yoo, Jong Su; Yim, Mi-Jin; Choi, Yung Hyun; Park, Saegwang; Seo, Su-Kil; Choi, Jung Sik; Lee, Young-Min; Park, Won Sun; Choi, Il-Whan

    2016-09-01

    Inflammasomes are multi-protein complexes that play a crucial role in innate immune responses. Benzyl isothiocyanate (BITC) is a naturally occurring compound found in cruciferous vegetables, and BITC exhibits potential as a chemopreventive agent. However, whether BITC exerts inflammasome-mediated regulatory effects on neuroinflammation is unknown. In this study, we examined the effects of BITC on inflammasome-mediated interleukin-1β (IL-1β) production in E. coli lipopolysaccharide (LPS)-stimulated BV2 microglial cells. IL-1β production is tightly regulated at the post-translational level through the inflammasoume. We measured the levels of IL-1β produced from the LPS-exposed BV2 microglial cells using enzyme-linked immunosorbent assays (ELISAs). The BITC regulatory mechanisms in inflammasome-mediated cellular signaling pathways were examined by RT-PCR, western blot analysis and electrophoretic mobility shift assays. BITC inhibited the secretion of IL-1β induced by LPS in the BV2 microglial cells. BITC inhibited inflammasome activation and NLR family, pyrin domain containing 3 (NLRP3)-mediated caspase-1 activation, and decreased the levels of inflammasome activation pro-inflammatory mediators, including mitochondrial reactive oxygen species (ROS) and adenosine triphosphate (ATP) secretion in the LPS-stimulated BV2 microglial cells. Furthermore, we demonstrated that nuclear factor-κB (NF-κB) activation induced by LPS was inhibited by BITC, which may contribute to the attenuated secretion of IL-1β. These BITC-mediated inhibitory effects on IL-1β expression may thus regulate neuroinflammation through the inflammasome-mediated signaling pathway. PMID:27430883

  7. A Radically Configurable Six-State Compound

    OpenAIRE

    Barnes, Jonathan C.; Fahrenbach, Albert C.; Cao, Dennis; Dyar, Scott M.; Frasconi, Marco; Giesener, Marc A.; Benítez, Diego; Tkatchouk, Ekaterina; Chernyashevskyy, Oleksandr; Shin, Weon Ho; Li, Hao; Sampath, Srinivasan; Stern, Charlotte L.; Sarjeant, Amy A.; Hartlieb, Karel J.

    2013-01-01

    Most organic radicals possess short lifetimes and quickly undergo dimerization or oxidation. Here, we report on the synthesis by radical templation of a class of air- and water-stable organic radicals, trapped within a homo[2]catenane composed of two rigid and fixed cyclobis (paraquat-p-phenylene) rings. The highly energetic octacationic homo[2]catenane, which is capable of accepting up to eight electrons, can be configured reversibly, both chemically and electrochemically, bet...

  8. Quantitative determination of atmospheric hydroperoxyl radical

    Energy Technology Data Exchange (ETDEWEB)

    Springston, Stephen R. (Upton, NY); Lloyd, Judith (Westbury, NY); Zheng, Jun (Stony Brook, NY)

    2007-10-23

    A method for the quantitative determination of atmospheric hydroperoxyl radical comprising: (a) contacting a liquid phase atmospheric sample with a chemiluminescent compound which luminesces on contact with hydroperoxyl radical; (b) determining luminescence intensity from the liquid phase atmospheric sample; and (c) comparing said luminescence intensity from the liquid phase atmospheric sample to a standard luminescence intensity for hydroperoxyl radical. An apparatus for automating the method is also included.

  9. Photodynamically generated bovine serum albumin radicals

    DEFF Research Database (Denmark)

    Silvester, J A; Timmins, G S; Davies, Michael Jonathan

    1998-01-01

    Porphyrin-sensitized photoxidation of bovine serum albumin (BSA) results in oxidation of the protein at (at least) two different, specific sites: the Cys-34 residue giving rise to a thiyl radical (RS.); and one or both of the tryptophan residues (Trp-134 and Trp-214) resulting in the formation of...... by a range of proteases. The generation of protein-derived radicals also results in an enhancement of photobleaching of the porphyrin, suggesting that protein radical generation is linked to porphyrin photooxidation....

  10. Involvement of free radicals in breast cancer

    OpenAIRE

    Ríos-Arrabal, Sandra; Artacho-Cordón, Francisco; León, Josefa; Román-Marinetto, Elisa; del Mar Salinas-Asensio, María; Calvente, Irene; Núñez, Maria Isabel

    2013-01-01

    Researchers have recently shown an increased interest in free radicals and their role in the tumor microenvironment. Free radicals are molecules with high instability and reactivity due to the presence of an odd number of electrons in the outermost orbit of their atoms. Free radicals include reactive oxygen and nitrogen species, which are key players in the initiation and progression of tumor cells and enhance their metastatic potential. In fact, they are now considered a hallmark of cancer. ...

  11. Optimal pain management for radical prostatectomy surgery

    DEFF Research Database (Denmark)

    Joshi, Grish P; Jaschinski, Thomas; Bonnet, Francis; Kehlet, Henrik

    2015-01-01

    evidence to develop an optimal pain management protocol in patients undergoing radical prostatectomy. Most studies assessed unimodal analgesic approaches rather than a multimodal technique. There is a need for more procedure-specific studies comparing pain and analgesic requirements for open and minimally...... invasive surgical procedures. Finally, while we wait for appropriate procedure specific evidence from publication of adequate studies assessing optimal pain management after radical prostatectomy, we propose a basic analgesic guideline.......BACKGROUND: Increase in the diagnosis of prostate cancer has increased the incidence of radical prostatectomy. However, the literature assessing pain therapy for this procedure has not been systematically evaluated. Thus, optimal pain therapy for patients undergoing radical prostatectomy remains...

  12. Near-Ring Radicals and Class Pairs

    Institute of Scientific and Technical Information of China (English)

    L.Godloza; N.J.Groenewald; W.A.Olivier

    2005-01-01

    For near-ring ideal mappings p1 and p2, we investigate radical theoretical properties of and the relationship among the class pairs (p1: p2), (Sp2: Sp1) and (Rp2:Rp1). Conditions on p1 and p2 are given for a general class pair to form a radical class of various types. These types include the Plotkin and KA-radical varieties. A number of examples are shown to motivate the suitability of the theory of Hoehnke-radicals over KA-radicals when radical pairs of near-rings are studied. In particular, it is shown that (pc: P3) forms a KA-radical class, where Pc denotes the class of completely prime nearrings and P3 the class of 3-prime near-rings. This gives another near-ring generalization of the 2-primal ring concept. The theory of radical pairs are also used to show that in general the class of 3-semiprime near-rings is not the semisimple class of the 3-prime radical.

  13. Dynamics of Radical-Mediated Enzyme Catalyses

    Science.gov (United States)

    Warncke, Kurt

    1997-11-01

    An emergent class of enzymes harnesses the extreme reactivity of electron-deficient free radical species to perform some of the most difficult reactions in biology. The regio- and stereo-selectivity achieved by these enzymes defies long-held ideas that radical reactions are non-specific. The common primary step in these catalyses is metal- or metallocenter-assisted generation of an electron-deficient organic "initiator radical". The initiator radical abstracts a hydrogen atom from the substrate, opening a new reaction channel for rearrangement to the product. Our aim is to elucidate the detailed molecular mechanisms of the radical pair separation and radical rearrangement steps. Radical pair separation and substrate radical rearrangement are tracked by using time-resolved (10-7 to 10-3 s) techniques of pulsed-electron paramagnetic resonance spectroscopy (FT-EPR, ESEEM). Synchronous time-evolution of the reactions is attained by triggering with a visible laser pulse. Transient non-Boltzmann population of the states of the spin-coupled systems, and resultant electron spin polarization, facilitates study at or near room temperature under conditions where the enzymes are operative. The systems examined include ethanolamine deaminase, a vitamin B12 coenzyme-dependent enzyme, ribonucleotide reductase and photosynthetic reaction centers. The electronic and nuclear structural and kinetic information obtained from the pulsed-EPR studies is used to address how the initiator radicals are stabilized against deleterious recombination with the metal, and to distinguish the participation of concerted versus sequential rearrangement pathways.

  14. The Games Radicals Play: Special Issue on Free Radicals and Radical Ions

    Directory of Open Access Journals (Sweden)

    John C. Walton

    2015-02-01

    Full Text Available Chemistry and Physics have aptly been described as “most excellent children of Intellect and Art” [1]. Both these “children” engage with many playthings, and molecules rank as one of their first favorites, especially radicals, which are amongst the most lively and exciting. Checking out radicals dancing to the music of entropy round their potential energy ballrooms is surely both entertaining and enlightening. Radicals’ old favorite convolutions are noteworthy, but the new styles, modes and arrangements appearing on the scene are even more interesting. Some of these are ephemeral and enjoy only a brief appearance, others are retro-types reappearing in new guises, still others are genuinely new and “go viral” in the scientific world. This Special Issue of Molecules contains the observations and reflections of a select group of chemists and physicists fascinated by this spectacle. It contains an eclectic mix reflecting on new modes and advances as well as on permutations and combinations that revive mature themes. [...

  15. Photoionisation of the tropyl radical

    Directory of Open Access Journals (Sweden)

    Kathrin H. Fischer

    2013-04-01

    Full Text Available We present a study on the photoionisation of the cycloheptatrienyl (tropyl radical, C7H7, using tunable vacuum ultraviolet synchrotron radiation. Tropyl is generated by flash pyrolysis from bitropyl. Ions and electrons are detected in coincidence, permitting us to record mass-selected photoelectron spectra. The threshold photoelectron spectrum of tropyl, corresponding to the X+ 1A1’ ← X 2E2” transition, reveals an ionisation energy of 6.23 ± 0.02 eV, in good agreement with Rydberg extrapolations, but slightly lower than the value derived from earlier photoelectron spectra. Several vibrations can be resolved and are reassigned to the C–C stretch mode ν16+ and to a combination of ν16+ with the ring breathing mode ν2+. Above 10.55 eV dissociative photoionisation of tropyl is observed, leading to the formation of C5H5+ and C2H2.

  16. Radical surgery in septic abortion.

    Science.gov (United States)

    Chatterjee, P; Ghosh, M; Ghosh, S

    1979-08-01

    At R.G. Kar Medical College Hospital, Calcutta, 10 cases of septic abortion from 1975-1977 were studied. Hysterectomies were preformed on 4 cases due to emergency situations including traumatised uterine fundus and perforated cervix, and on 6 cases after conservative treatment. Upon performing laparotomy in 9 cases, a uterine rent was detected; in 1 case there was a perforation in the posterior wall of the cervix, and in 5 cases mechanical obstructions due to internal adhesions to the uterine rent were found. 4 patients died primarily because of the patients seeking help too late. It is suggested that under high risk circumstances, laparotomy is advantageous to conservative medical management since bowel injuries and mechanical obstructions can only be detected by laparotomy. Radical surgery, however, should be undertaken before the patients general condition deteriorates to the point that the patient cannot tolerate surgical intervention. PMID:12336028

  17. Students' Ideas and Radical Constructivism

    Science.gov (United States)

    Sánchez Gómez, Pedro J.

    2016-08-01

    In this article, I study, from the point of view of the analytic philosophy of mind, the compatibility of students' ideas studies (SIS) with radical constructivism (RC). I demonstrate that RC is based on a psychology of narrow mental states; that is, the idea that the mental content of an individual can be fully characterised without any reference external to her or him. I show that this fact imposes some severe restrictions to SIS to be incorporated into RC. In particular, I argue that only qualitative studies can comply with the requirement of narrowness. Nevertheless, I propose that quantitative works can be employed as sources of types in order to study token actual students. I use this type-token dichotomy to put forward an outline of a theory of the relation between school contents and mental contents. In this view, token mental contents regarding a given topic can be defined, and probed, only by resorting to typical school contents.

  18. Students' Ideas and Radical Constructivism

    Science.gov (United States)

    Sánchez Gómez, Pedro J.

    2016-04-01

    In this article, I study, from the point of view of the analytic philosophy of mind, the compatibility of students' ideas studies (SIS) with radical constructivism (RC). I demonstrate that RC is based on a psychology of narrow mental states; that is, the idea that the mental content of an individual can be fully characterised without any reference external to her or him. I show that this fact imposes some severe restrictions to SIS to be incorporated into RC. In particular, I argue that only qualitative studies can comply with the requirement of narrowness. Nevertheless, I propose that quantitative works can be employed as sources of types in order to study token actual students. I use this type-token dichotomy to put forward an outline of a theory of the relation between school contents and mental contents. In this view, token mental contents regarding a given topic can be defined, and probed, only by resorting to typical school contents.

  19. Iron and iron derived radicals

    Energy Technology Data Exchange (ETDEWEB)

    Borg, D.C.; Schaich, K.M.

    1987-04-01

    We have discussed some reactions of iron and iron-derived oxygen radicals that may be important in the production or treatment of tissue injury. Our conclusions challenge, to some extent, the usual lines of thought in this field of research. Insofar as they are born out by subsequent developments, the lessons they teach are two: Think fastexclamation Think smallexclamation In other words, think of the many fast reactions that can rapidly alter the production and fate of highly reactive intermediates, and when considering the impact of competitive reactions on such species, think how they affect the microenvironment (on the molecular scale) ''seen'' by each reactive molecule. 21 refs., 3 figs., 1 tab.

  20. Inhibitory effects of chitosan on superoxide anion radicals and lipid free radicals

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    With the electron spin resonance (ESR) technique, the inhibitory effects of chitosan on superoxide anion radicals and linoleic acid lipid radicals were found. The inhibitory ratio E for these two kinds of radicals is in proportion to the concentration of chitosan. It was also observed that E for linoleic acid lipid radicals increased with the increase of the degree of deacetylation and decreased with the increase of the molecular weight of chitosan.

  1. Alkali and alkaline earth metal salts of boron anionic complexes with o-hydroxy-benzyl alcohols (saligenin)

    International Nuclear Information System (INIS)

    Salts of two anionic boron complexes with 2 hydroxy-benzyl alcohol-[BA2- and [B(OH)2A]- - were synthesized. The first complex was separated in the form of anhydrous potassium and cesium salts, the second one - in the form of sodium (dihydrate), calcium (dihydrate) and barium (tetrahydrate and anhydrous salt) salts. Conditions of formation are discussed. Solubility in water and organic solvents, interplanar distances of crystal lattice were determined. The compounds were studied by the methods of infrared spectroscopy, thermal analysis. Hypothetical composition of the compounds is given

  2. Benzyl-1,2,4-triazoles as CB1 Cannabinoid Receptor Ligands: Preparation and In Vitro Pharmacological Evaluation

    Science.gov (United States)

    Hernandez-Folgado, Laura; Decara, Juan; Rodríguez de Fonseca, Fernando; Goya, Pilar; Jagerovic, Nadine

    2016-01-01

    In a previous study, we have identified 3-alkyl-1,5-diaryl-1H-1,2,4-triazoles to be a novel class of cannabinoid type 1 receptor (CB1R) antagonists. In order to expand the number of cannabinoid ligands with a central 1,2,4-triazole scaffold, we have synthesized a novel series of 1-benzyl-1H-1,2,4-triazoles, and some of them were evaluated by CB1R radioligand binding assays. Compound 12a showed the most interesting pharmacological properties, possessing a CB1R affinity in the nanomolar range. PMID:27127651

  3. Visible-light-driven selective oxidation of benzyl alcohol and thioanisole by molecular ruthenium catalyst modified hematite.

    Science.gov (United States)

    Bai, Lichen; Li, Fei; Wang, Yong; Li, Hua; Jiang, Xiaojuan; Sun, Licheng

    2016-08-11

    Molecular ruthenium catalysts were found to selectively catalyze the oxidation of thioanisole to sulfoxide with a yield up to 100% in the presence of visible light and sacrificial reagents when they were anchored onto hematite powder. The composite photocatalysts also showed about 5 times higher efficiencies in benzyl alcohol oxidation than the system composed of dispersed molecular catalysts and hematite particles in aqueous solution. A photoelectrochemical cell based on a molecular catalyst modified hematite photoanode was further fabricated, which exhibited high activity towards the oxidation of organic substrates. PMID:27411498

  4. A study of transglucosylation kinetic in an enzymatic synthesis of benzyl alcohol glucoside by α-glucosidase from S. cerevisiae

    Science.gov (United States)

    Pavlović, M.; Dimitrijević, A.; Trbojević, J.; Milosavić, N.; Gavrović-Jankulović, M.; Bezbradica, D.; Veličković, D.

    2013-12-01

    α-1,4-Glucosidase from Saccharomyces cerevisiae is an enzyme which is widely used in synthesis of different drugs. Glucosidase inhibitors are studied as potential drugs for prevention of HIV and diabetes. For understanding of these processes it is very important to have insights in the transglucosylation activity of this enzyme. In this paper the kinetics of transglucosylation reaction catalyzed by this enzyme in the synthesis of benzyl alcohol glucoside was studied and all relevant kinetic constants for this system are found. It was shown one additional property of transglycosylation reactions catalyzed by glycosidases—inhibition by both, glucose acceptor and glucose donor, and mechanisms for these inhibitions were proposed.

  5. Anchoring Tri(8-QuinolinolatoIron Onto Sba-15 for Partial Oxidation of Benzyl Alcohol Using Water as the Solvent

    Directory of Open Access Journals (Sweden)

    Yang Xiaoyuan

    2014-09-01

    Full Text Available Tri(8-quinolinolatoiron complex immobilized onto SBA-15 catalyst has been synthesized through a stepwise procedure. The characterization results indicated that the BET surface area, total pore volume and average pore width decrease after stepwise modification of SBA-15, while the structure keeps intact. Catalytic tests showed that FeQ3-SBA-15 catalyzes the oxidation reaction well with 34.8% conversion of benzyl alcohol and 74.7% selectivity to benzaldehyde when water is used as the solvent after 1 h reaction. In addition, homogeneous catalyst tri(8-quinolinolatoiron exhibits very bad catalytic behavior using water as the solvent.

  6. Tetranuclear vanadium complex, (VO)(4)(hpic)(4): a recyclable catalyst for oxidation of benzyl alcohols with molecular oxygen.

    Science.gov (United States)

    Kodama, Shintaro; Ueta, Yukihiro; Yoshida, Jun; Nomoto, Akihiro; Yano, Shigenobu; Ueshima, Michio; Ogawa, Akiya

    2009-11-28

    Vanadium(iv) complexes bearing 3-hydroxypicolinic acid (H(2)hpic) as ligands, VO(Hhpic)(2) (1) and the cyclic tetramer (VO)(4)(hpic)(4) (2), have excellent catalytic ability for the oxidation of a variety of primary and secondary benzyl alcohols with molecular oxygen in acetonitrile or protic solvents such as ethanol and water, affording the corresponding aldehydes and ketones, respectively. Construction of multi-nuclear complexes by the selection of ligands attains higher turnover numbers and recycling of the catalyst. PMID:19885511

  7. Modification of Carboxymethyl Chitosan Film by Blending with Poly(benzyl L-glutamate)-block-poly(ethylene glycol) Copolymer

    International Nuclear Information System (INIS)

    A series of water-soluble carboxymethyl chitosan (CMCS)/poly(benzyl L-glutamate)-block-poly(ethylene glycol) (PBLG-b-PEG) blend films with various CMCS/PBLG-b-PEG mol ratios were prepared by pervaporation method. Morphologies of CMCS/PBLG-b-PEG blend films were researched by scanning electron microscopy (SEM). Thermal, mechanical, and chemical properties of CMCS/PBLG-b-PEG blend films were investigated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), tensile tests, and contact angle tests. It was revealed that the introduction of PBLG-b-PEG segments could greatly affect the morphology and the properties of CMCS films. (author)

  8. Coenzyme B12 model studies: Equilibrium constants for the H-dependent axial ligation of benzyl(aquo)cobaloxime by various N- and S-donor ligands

    Indian Academy of Sciences (India)

    D Sudarshan Reddy; N Ravi Kumar Reddy; V Sridhar; S Satyanarayana

    2002-02-01

    Equilibria of the axial ligation of benzyl(aquo)cobaloximes by imidazole, 1-methyl imidazole, histidine, histamine, glycine, ethyl glycine ester, thiourea and urea have been spectrophotometrically measured in aqueous solutions of ionic strength 1.0 M (KCl) at 25°C as a function of H. The equilibrium constants are in the order CN- > 1-methyl imidazole > imidazole > histidine > histamine > glycine > ethyl glycine ester > thiourea > urea. The order of stability of benzyl(ligand)cobaloxime is explained based on the basicity of the ligand, Co(III) → - back bonding and soft-soft and soft-hard interaction. Imidazole, substituted imidazoles, histidine and histamine form more stable complexes than glycine, ethyl glycine ester in contrast to the basicity of the ligands. Benzyl(ligand)cobaloximes were isolated and characterized by elemental analysis, IR and 1H NMR spectra.

  9. 1-O-Acetyl-3,4,6-tri-O-benzyl-2-C-bromomethyl-2-deoxy-α-d-glucopyranose

    Directory of Open Access Journals (Sweden)

    Henok H. Kinfe

    2013-01-01

    Full Text Available In the title compound, C30H33BrO6, the pyranose ring adopts a chair conformation. Two of the O-benzyl phenyl rings lie almost perpendicular to C/C/C/O plane formed by the ring atoms not attached to these O-benzyl phenyl rings, and form dihedral angles of 85.1 (2 and 64.6 (2°, while the third O-benzyl phenyl ring is twisted so that it makes a dihedral angle 34.9 (2° to this C/C/C/O plane. This twist is ascribed to the formation of an S(8 loop stabilized by a weak intramolecular C—H...O hydrogen bond.

  10. Radical Behaviorism and Buddhism: Complementarities and Conflicts

    Science.gov (United States)

    Diller, James W.; Lattal, Kennon A.

    2008-01-01

    Comparisons have been made between Buddhism and the philosophy of science in general, but there have been only a few attempts to draw comparisons directly with the philosophy of radical behaviorism. The present review therefore considers heretofore unconsidered points of comparison between Buddhism and radical behaviorism in terms of their…

  11. Radical-Local Teaching and Learning

    DEFF Research Database (Denmark)

    Hedegaard, Mariane; Chaiklin, Seth

    radical-local teaching and learning approach. The first half of the book introduces the idea of radical-local teaching and learning and develops the theoretical background for this perspective, drawing on the cultural-historical research tradition, particularly from Vygotsky, El'konin, Davydov...

  12. What Is Radical in School Geography Today?

    Science.gov (United States)

    Morgan, John

    2011-01-01

    This article addresses the question of what "radical school geography" might look like in the present historical moment. It traces the history of a distinctive "radical" tradition in school geography, most prominently associated with the work of John Huckle, who argued for the importance of understanding the content and pedagogy of school…

  13. Free Radical Mechanisms in Autoxidation Processes.

    Science.gov (United States)

    Simic, Michael G.

    1981-01-01

    Discusses the use of steady-state radiation chemistry and pulse radiolysis for the generation of initial free radicals and formation of peroxy radicals in the autoxidation process. Provides information regarding the autoxidation process. Defines autoxidation reactions and antioxidant action. (CS)

  14. Sulfamic acid as a cost-effective and recyclable solid acid catalyst for Friedel-Crafts alkylation of indole with α,β-unsaturated carbonyl compound and benzyl alcohol

    Institute of Scientific and Technical Information of China (English)

    Jing Yang; Juan Zhang; Tian Tian Chen; De Mei Sun; Ji Li; Xue Fen Wu

    2011-01-01

    Sulfamic acid was proved to be a cost-effective and recyclable catalyst for Friedel-Crafts type reaction of indole with α,β-unsaturated carbonyl compound and benzyl alcohol. Various indoles, α,β-unsaturated carbonyl compounds and a benzyl alcohol were successfully used in this type of reaction, and the corresponding products were obtained in good to excellent yields.

  15. 1, 3-Dipolar cycloaddition reactions: Synthesis of 5-benzyl-1-(2',4'-dibromophenyl)-3-(4"-substituted phenyl)-3a,4,6,6a-tetrahydro-1, 5-pyrrolo[3,4-]pyrazole-4,6-dione derivatives

    Indian Academy of Sciences (India)

    Manpreet Kaur; Baldev Singh; Baljit Singh

    2013-11-01

    1,3-Dipolar cycloaddition of nitrilimines 3 with -benzyl maleimide 4 has provided 5-benzyl-1-(2',4'-dibromophenyl)-3-(4"-substituted phenyl)-3a,4,6,6a-tetrahydro-1,5-pyrrolo[3,4-]pyrazole-4,6-dione derivatives 5 in excellent yield as the only isomer through a concerted pathway.

  16. Novel Synthesis and Anti-HIV-1 Activity of 2-Arylthio-6-benzyl-2,3-dihydro-1H-pyrimidin-4-ones (Aryl S-DABOs)

    DEFF Research Database (Denmark)

    Aly, Youssef L.; Pedersen, Erik Bjerreg.; La Colla, Paolo;

    2007-01-01

    The synthesis and the anti-HIV-1 activity of a series of 2-arylthio-6-benzyl-2,3-dihydro-1H-pyrimidin-4-ones (aryl S-DABOs) are reported. These compounds were synthesized via a coupling reaction of the corresponding 6-benzyl-2-thiouracils with aryl iodides in the presence of neocuproine hydrate, ...

  17. Physicochemical aspects of isomerisation of free radicals

    Energy Technology Data Exchange (ETDEWEB)

    Denisov, Evgenii T; Denisova, Taisa G [Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka, Moscow Region (Russian Federation)

    2004-11-30

    Kinetic data on intramolecular abstraction of hydrogen atoms in alkyl, alkoxyl and peroxyl radicals are generalised and analysed. It is shown that the activation energies of these reactions are affected by ring strain. The kinetic parameters of mono- and bimolecular elimination reactions are compared. The difference between the activation energies of these reactions is interpreted using the model of intersecting parabolas. The same model is used to discuss the results of analysis of cyclisation of alkyl radicals; the ring strain energy is shown to play an important role in the activation of these reactions. It is noted that the difference between the electron affinities of the C, N and O atoms is clearly manifested in the cyclisation of aminyl and {omega}-formylalkyl radicals. The kinetic parameters of cyclisation and bimolecular radical addition reactions are compared. The experimental data on the transfer of the vinyl and aryl groups in alkyl radicals are analysed.

  18. A novel serotonin transporter ligand: (5-Iodo-2-(2-dimethylaminomethylphenoxy)-benzyl alcohol

    Energy Technology Data Exchange (ETDEWEB)

    Zhuang, Z.-P.; Choi, S.-R.; Hou, Catherine; Mu Mu; Kung, M.-P. E-mail: kunghf@sunmac.spect.upenn.edu; Acton, Paul D.; Kung, Hank F

    2000-02-01

    The serotonin transporters (SERT) are the primary binding sites for selective serotonin reuptake inhibitors, commonly used antidepressants such as fluoxetine, sertraline, and paroxetine. Imaging of SERT with positron emission tomography and single photon emission computed tomography in humans would provide a useful tool for understanding how alterations of this system are related to depressive illnesses and other psychiatric disorders. In this article the synthesis and characterization of [{sup 125}I]ODAM [(5-iodo-2-(2-dimethylaminomethylphenoxy)-benzyl alcohol, 9)] as an imaging agent in the evaluation of central nervous system SERT are reported. A new reaction scheme was developed for the preparation of compound 9, ODAM, and the corresponding tri-n-butyltin derivative 10. Upon reacting 10 with hydrogen peroxide and sodium[{sup 125}I]iodide, the radiolabeled [{sup 125}I]9 was obtained in good yield (94% yield, radiochemical purity >95%). In an initial binding study using cortical membrane homogenates of rat brain, ODAM displayed a good binding affinity with a value of K{sub i}=2.8{+-}0.88 nM. Using LLC-PK{sub 1} cells specifically expressing the individual transporter (i.e. dopamine [DAT], norepinephrine [NET], and SERT, respectively), ODAM showed a strong inhibition on SERT (K{sub i}=0.12{+-}0.02 nM). Inhibition constants for the other two transporters were lower (K{sub i}=3.9{+-}0.7 {mu}M and 20.0 {+-} 1.9 nM for DAT and NET, respectively). Initial biodistribution study in rats after an intravenous (IV) injection of [{sup 125}I]ODAM showed a rapid brain uptake and washout (2.03, 1.49, 0.79, 0.27, and 0.07% dose/organ at 2, 30, 60, 120, and 240 min, respectively). The hypothalamus region where the serotonin neurons are located exhibited a high specific uptake. Ratios of hypothalamus-cerebellum/cerebellum based on percent dose per gram of these two regions showed values of 0.35, 0.86, 0.86, 0.63, and 0.34 at 2, 30, 60, 120, and 240 min, post-IV injection

  19. Benzyl and Methyl Fatty Hydroxamic Acids Based on Palm Kernel Oil as Chelating Agent for Liquid-Liquid Iron(III) Extraction

    OpenAIRE

    Jamileh Amin; Roshanak Rafiee-Moghaddam; Behnam Mahdavi; Mazyar Peyda; Anuar Kassim; Nor Azah Yusof; Md Jelas Haron; Hossein Jahangirian; Yadollah Abdollahi; Sidik Silong

    2012-01-01

    Liquid-liquid iron(III) extraction was investigated using benzyl fatty hydroxamic acids (BFHAs) and methyl fatty hydroxamic acids (MFHAs) as chelating agents through the formation of iron(III) methyl fatty hydroxamate (Fe-MFHs) or iron(III) benzyl fatty hydroxamate (Fe-BFHs) in the organic phase. The results obtained under optimized conditions, showed that the chelating agents in hexane extract iron(III) at pH 1.9 were realized effectively with a high percentage of extraction (97.2% and 98.1%...

  20. The role of mesoporosity and Si/Al ratio in the catalytic etherification of glycerol with benzyl alcohol using ZSM-5 zeolites

    OpenAIRE

    Gonzalez-Arellano, Camino; Grau Atienza, Aida; Serrano Torregrosa, Elena; Antonio A. Romero; García Martínez, Javier; Luque, Rafael

    2015-01-01

    A comparative study of the influence of three different acid solids as catalysts (conventional zeolites Z15c with Si/Al = 19.5 and Z40c with Si/Al = 48.2, and a hierarchical zeolite Z40c-H with Si/Al = 50.0) for the etherification of glycerol with benzyl alcohol was performed. The catalytic activity and selectivity of these zeolites was elucidated at different catalyst contents. Three different ethers (3-benzyloxy-1,2-propanediol, which is a mono-benzyl-glycerol ether (MBG) and 1,3-dibenzylox...

  1. (1S,3S,4S)-tert-Butyl N-[1-benzyl-3-hydr­oxy-5-phenyl-4-(picolinamido)pent­yl]carbamate

    OpenAIRE

    Jian-Feng Zheng; Su-Yu Huang; Jian-Nan Guo; Yu Zhang; Li-Ren Jin

    2008-01-01

    The title compound, C29H35N3O4, was obtained by the reaction of (2S,4S,5S)-tert-butyl N-(4-amino-1-benzyl-3-hydroxy-5-phenylpentyl)carbamate and picolinic acid using oxalyl chloride as a chlorinating reagent to activate the carboxyl group. In the crystal structure there are two molecules in the asymmetric unit, which are aligned edge-to-face. In one molecule, the pyridyl ring forms a dihedral angle of 22.0 (1)° with the phenyl ring of the terminal benzyl group and 14.3 (1)...

  2. Modification of polysulfone membranes via surface-initiated atom transfer radical polymerization

    International Nuclear Information System (INIS)

    Hydrophilic poly((poly(ethylene glycol) methyl ether methacrylate) (P(PEGMA)) and poly(glycidylmethacrylate) (PGMA) brushes were grafted from chloromethylated polysulfone (CMPSF) membrane surfaces via surface-initiated atom transfer radical polymerization (ATRP). Prior to ATRP, chloromethylation of PSF was performed beforehand and the obtained CMPSF was prepared into porous membranes by phase inversion process. It was demonstrated that the benzyl chloride groups on the CMPSF membrane surface afforded effective macroinitiators to graft the well-defined polymer brushes. 1H NMR was employed to confirm the structure of CMPSF. The grafting yield of P(PEGMA) and PGMA was determined by weight gain measurement. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) confirmed the grafting of P(PEGMA) and PGMA chains. Water contact angle measurements indicated that the introduction of P(PEGMA) and PGMA graft chains promoted remarkably the surface hydrophilicity of PSF membranes. The effects of P(PEGMA) and PGMA immobilization on membrane morphology, permeability and fouling resistance were investigated. It was found that P(PEGMA) and PGMA grafts brought higher pure water flux, improved hydrophilic surface and better anti-protein absorption ability to PSF membranes after modification. And evidently, macromonomer P(PEGMA) brought much better properties to the PSF membranes than PGMA macromonomer.

  3. Hydroxyl-radical-induced oxidation of cyclic dipeptides: Reactions of free peptide radicals and their peroxyl radicals

    International Nuclear Information System (INIS)

    In the course of this study investigations were carried out into the reactions of hydroxyl radicals and hydrogen atoms with cyclic dipeptides as well as the subsequent reactions of peptide radicals and their peroxyl radicals in aqueous solution. The radiolysis products formed in the absence and presence of oxygen or transient metal complexes were characterized and determined on a quantitative basis. The linking of information from product analyses to the kinetic data for transient species obtained by time-resolving UV/VIS and conductivity measurements (pulse radiolysis) as well as computer-assisted simulations of individual events during the reaction permitted an evaluation of the mechanisms underlying the various processes and an identification of interim products with short life-times, which did or did not belong to the group of radicals. Through the characterization of key reactions of radicals and peroxyl radicals of this substance class a major advance has been made towards a better understanding of the role of radicals in the peptide compound and the mechanisms involved in indirect radiation effects on long-chain peptides and proteins. (orig.)

  4. Content determination of benzyl glucosinolate and anti-cancer activity of its hydrolysis product inCarica papaya L.

    Institute of Scientific and Technical Information of China (English)

    Ze-You Li; Yong Wang; Wen-Tao Shen; Peng Zhou

    2012-01-01

    Objective:To determine the content of benzyl glucosinolate(BG)in the pulp and the seed and investigate the anti-cancer activity of its hydrolysis product inCarica papaya L.Methods:Determination ofBG was performed on an HypersilBDS C18 column at the wavelength of214 nm with0.1% trifluoroacetic acid (TFA)aqueous solution (A) and 0.1%TFA acetonitrile (B)as the mobile phase. In vitro activity test was adopted with cultured human lung cancerH69 cellin vitro to investigate the inhibition rate of cell proliferation of benzyl isothiocyanate(BITC)againstH69 cell.Results: The pulp has more BG before the maturation of papaya and it nearly disappeared after papaya matured, while the seed containsBG at every stage. Activity test demonstrated that the a higher concentration ofBITC would have better inhibition rate of cell proliferation onH69 cell, and the IC50 was6.5 μmol/L.Conclusions:BG also can be produced in the pulp of papaya and it will be stored in the seed after the fruit has been matured. The hydrolysis product ofBG has certain cancer-prevention anti-cancer activities for human.

  5. Progress in synthesis of benzyl acetate%乙酸苄酯的合成研究进展

    Institute of Scientific and Technical Information of China (English)

    马松艳; 于冬梅; 赵东江; 乔秀丽; 白晓波; 董艳萍

    2009-01-01

    Benzyl acetate is a colorless transparent liquid, which has sweet-smelling of jasmine aroma and fruit,and is widely used as food and cosmetics essence. The catalytic synthesis of benzyl acetate with inorganic salt,solid superacid,heteropoly acid,sulfonic acid,phase-transfer, strongly acidic cation exchange resin,room temperature ionic liquids,microemulsion catalysts was reviewed. Advantages and shortcomings as catalytic properties of each catalyst were evaluated.%乙酸苄酯是无色透明油状的液体,具有茉莉花香气和水果香味,多用作食品和化妆品的香精.介绍了无机盐、固体超强酸、杂多酸、磺酸类、相转移、强酸性阳离子交换树脂、室温离子液体、微乳等催化剂催化合成乙酸苄酯的方法,并对各种催化剂的性能、优缺点进行了评价.

  6. Selective Aerobic Oxidation of Benzyl Alcohol Driven by Visible Light on Gold Nanoparticles Supported on Hydrotalcite Modified by Nickel Ion

    Directory of Open Access Journals (Sweden)

    Dapeng Guo

    2016-04-01

    Full Text Available A series of hydrotalcite (HT and hydrotalcite modified by the transition metal ion Ni(II was prepared with a modified coprecipitation method before being loaded with gold nanoparticles. The gold supported on Ni3Al hydrotalcite with a Ni2+/Al3+ molar ratio of 3:1 was investigated. Different techniques such as X-ray diffraction (XRD, X-ray photoelectron spectroscopy (XPS and UV-vis diffuse reflection spectrum (UV-vis DRS were applied to characterize the catalysts. A single-phase catalyst with high crystallinity, a layered structure and good composition was successfully fabricated. Good conversions and superior selectivities in the oxidation of benzyl alcohol and its derivatives were obtained with visible light due to the effect of localized surface plasmon resonance (LSPR of gold nanoparticles and the synergy of the transition metal ion Ni(II. This reaction was proven to be photocatalytic by varying the intensity and wavelength of the visible light. The catalyst can be recycled three times. A corresponding photocatalytic mechanism of the oxidation reaction of benzyl alcohol was proposed.

  7. A Pronounced Halogen Effect on the Organogelation Properties of Peripherally Halogen Functionalized Poly(benzyl ether) Dendrons.

    Science.gov (United States)

    Feng, Yu; Chen, Hui; Liu, Zhi-Xiong; He, Yan-Mei; Fan, Qing-Hua

    2016-03-24

    An interesting halogen-substituent effect on the organogelation properties of poly(benzyl ether) dendrons is reported. A new class of poly(benzyl ether) dendrons with halo substituents decorating their periphery was synthesized and fully characterized. A systematic study on the gelation abilities, thermotropic behaviors, aggregated microstructures, and mechanical properties of self-assembled organogels was performed to elucidate the halogen-substituent effects on their organogelation propensity. It was found that the exact halogen substitutions on the periphery of dendrons exert a profound effect on the organogelation propensity, and dendrons Gn -Cl (n=2, 3) and G2 -I proved to be highly efficient organogelators. The cooperation of multiple π-π, dispersive halogen, CH-π, and weak C-H⋅⋅⋅X hydrogen-bonding interactions were found to be the key contributor to forming the self-assembled gels. Dendritic organogels formed from Gn -Cl (n=2, 3) in 1,2-dichloroethane exhibited thixotropic-responsive properties, and such thixotropic organogels are promising materials for future research and applications. PMID:26916094

  8. ORGASMIC FUNCTION AFTER RADICAL PROSTATECTOMY

    Directory of Open Access Journals (Sweden)

    D. Yu. Pushkar

    2014-07-01

    Full Text Available Objective: to study orgasmic function (OF in patients undergoing radical prostatectomy (RPE.Subjects and methods. Seventy-nine patients who had undergone RPE for locally advanced prostate cancer without hormone and radiation therapies were examined. The patients’ mean age was 59.3 years. The mean EF-IIEF domain score was 24.4. OF was estimated by IIEF question 10 and the authors’ questionnaire. The Spearman rank correction coefficient and Mann-Whitney U-Wilcoxon tests were used.Results. After RPE, there was a reduction in the mean IIEF question 10 score from 3.9 (confidence interval 3.7–4.1 to 3.3 (3–3.5 (p = 0.000. The following changes were found in orgasm intensity: no changes in 43 %, mild worsening in 42 %, severe worsening in 8 %, and enhancement in 4 %; orgasm could not be achieved in 4 % of the patients. Pain usually of low intensity was reported by 8.8 %. The poor factors for preserving OF were its low baseline level, elderly age, or severe post-RPE erectile dysfunction.Conclusion. There were significant OF changes after RPE, which should be kept in mind while treating this category of patients.

  9. Generation of radicals by bimolecular reactions

    Energy Technology Data Exchange (ETDEWEB)

    Denisov, Evgenii T; Denisova, Taisa G [Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka, Moscow Region (Russian Federation)

    2002-05-31

    The published data on bimolecular processes of radical generation in chain degradation, polymerisation, oxidation and halogenation reactions of organic compounds are systematised and analysed within the framework of the parabolic model of homolytic bimolecular reactions. The specific features of these highly endothermic reactions are discussed with a special emphasis on their striking similarity to radical abstraction processes with identical reaction centres in the transition state. The feasibility of theoretical evaluation of the activation energies and the rate constants of bimolecular reactions in radical generation is demonstrated. The bibliography includes 86 references.

  10. Some reactions of oxidizing radicals with enzymes in aqueous solution

    International Nuclear Information System (INIS)

    A range of oxidizing radicals including some inorganic radical anions and the superoxide radical, can be generated by radiolysis of aqueous solutions. These radicals are more selective in their reactions with amino acids than the hydroxyl radical. Factors controlling the apparent reactivity of radical anions with proteins, such as free radical equilibria and ion-binding, are described. The superoxide radical inactivates papain by reaction with the cysteine residue. This reaction has been studied in solutions subjected to radiations of varying linear energy transfer. (Auth.)

  11. Radical pancreaticoduodenectomy for benign disease.

    LENUS (Irish Health Repository)

    Kavanagh, D O

    2008-01-01

    Whipple\\'s procedure is the treatment of choice for pancreatic and periampullary malignancies. Preoperative histological confirmation of malignancy is frequently unavailable and some patients will subsequently be found to have benign disease. Here, we review our experience with Whipple\\'s procedure for patients ultimately proven to have benign disease. The medical records of all patients who underwent Whipple\\'s procedure during a 15-year period (1987-2002) were reviewed; 112 patients underwent the procedure for suspected malignancy. In eight cases, the final histology was benign (7.1%). One additional patient was known to have benign disease at resection. The mean age was 50 years (range: 30-75). The major presenting features included jaundice (five), pain (two), gastric outlet obstruction (one), and recurrent gastrointestinal haemorrhage (one). Investigations included ultrasound (eight), computerised tomography (eight), endoscopic retrograde cholangiopancreatography (seven; of these, four patients had a stent inserted and three patients had sampling for cytology), and endoscopic ultrasound (two). The pathological diagnosis included benign biliary stricture (two), chronic pancreatitis (two), choledochal cyst (one), inflammatory pseudotumour (one), cystic duodenal wall dysplasia (one), duodenal angiodysplasia (one), and granular cell neoplasm (one). There was no operative mortality. Morbidity included intra-abdominal collection (one), anastomotic leak (one), liver abscess (one), and myocardial infarction (one). All patients remain alive and well at mean follow-up of 41 months. Despite recent advances in diagnostic imaging, 8% of the patients undergoing Whipple\\'s procedure had benign disease. A range of unusual pathological entities can mimic malignancy. Accurate preoperative histological diagnosis may have allowed a less radical operation to be performed. Endoscopic ultrasound-guided fine needle aspirate (EUS-FNA) may reduce the need for Whipple\\'s operation

  12. Radical Pancreaticoduodenectomy for Benign Disease

    Directory of Open Access Journals (Sweden)

    D. O. Kavanagh

    2008-01-01

    Full Text Available Whipple's procedure is the treatment of choice for pancreatic and periampullary malignancies. Preoperative histological confirmation of malignancy is frequently unavailable and some patients will subsequently be found to have benign disease. Here, we review our experience with Whipple's procedure for patients ultimately proven to have benign disease. The medical records of all patients who underwent Whipple's procedure during a 15-year period (1987–2002 were reviewed; 112 patients underwent the procedure for suspected malignancy. In eight cases, the final histology was benign (7.1%. One additional patient was known to have benign disease at resection. The mean age was 50 years (range: 30–75. The major presenting features included jaundice (five, pain (two, gastric outlet obstruction (one, and recurrent gastrointestinal haemorrhage (one. Investigations included ultrasound (eight, computerised tomography (eight, endoscopic retrograde cholangiopancreatography (seven; of these, four patients had a stent inserted and three patients had sampling for cytology, and endoscopic ultrasound (two. The pathological diagnosis included benign biliary stricture (two, chronic pancreatitis (two, choledochal cyst (one, inflammatory pseudotumour (one, cystic duodenal wall dysplasia (one, duodenal angiodysplasia (one, and granular cell neoplasm (one. There was no operative mortality. Morbidity included intra-abdominal collection (one, anastomotic leak (one, liver abscess (one, and myocardial infarction (one. All patients remain alive and well at mean follow-up of 41 months. Despite recent advances in diagnostic imaging, 8% of the patients undergoing Whipple'’s procedure had benign disease. A range of unusual pathological entities can mimic malignancy. Accurate preoperative histological diagnosis may have allowed a less radical operation to be performed. Endoscopic ultrasound–guided fine needle aspirate (EUS-FNA may reduce the need for Whipple's operation in

  13. Kinetics of pyrolysis of a coal model compound, 2-picoline, the nitrogen heteroaromatic analogue of toluene. 2. The 2-picolyl radical and kinetic modeling

    International Nuclear Information System (INIS)

    The pyrolysis of 2-picoline, investigated experimentally in our previous paper, has been successfully modeled using a 70-reaction free-radical mechanism. The mechanism includes decomposition pathways of o-pyridyl and 2-picolyl, both of which are formed through the principal initiation reactions of 2-picoline. The proposed mechanism for 2-picolyl decomposition involves the direct ring opening of the 2-picolyl radical. Further reactions of the open chain isomer of 2-picolyl resulted in the formation of the major products HCN and acetylene and the minor products 1-cyanocyclopentadiene and cyclopentadiene. Kinetic modeling confirmed the feasibility of this mechanism by predicting the observed profiles for these species. Optimizing of the heat of formation of 2-picolyl through kinetic modeling resulted in a value of 68 (± 5) kcal mol-1. This value suggests a lower level of resonance stabilization for 2-picolyl compared to benzyl. This inference is supported by the normal value of the rate constant for 2-picolyl + H recombination found by modeling to be in the range 1 x 1013 6 x 1013 cm3 mol-1 s-1. The reactant and product profiles predicted by the kinetic model were found to be very sensitive to the rate of the initiation reaction yielding methyl and o-pyridyl radicals. 43 refs., 8 figs., 3 tabs

  14. Catalytic Z-Selective Cross-Metathesis with Secondary Silyl- and Benzyl-Protected Allylic Ethers: Mechanistic Aspects and Applications to Natural Product Synthesis**

    OpenAIRE

    Mann, Tyler J.; Speed, Alexander W. H.; Schrock, Richard R.; Hoveyda, Amir H.

    2013-01-01

    Efficient catalytic cross-metathesis reactions that afford Z-disubstituted allylic silyl or benzyl ethers are reported (see scheme, MAP=monoalkoxide pyrrolide). The approach, in combination with catalytic cross-coupling, provides a general entry to otherwise difficult-to-access alkyne-containing Z olefins.

  15. A simple and convenient one-pot synthesis of substituted isoindolin-1-ones via lithiation, substitution and cyclization of N'-benzyl-N,N-dimethylureas

    Directory of Open Access Journals (Sweden)

    Keith Smith

    2011-09-01

    Full Text Available Lithiation of N'-benzyl-N,N-dimethylurea and its substituted derivatives with t-BuLi (3.3 equiv in anhydrous THF at 0 °C followed by reaction with various electrophiles afforded a range of 3-substituted isoindolin-1-ones in high yields.

  16. Azido-Iodo-N-Benzyl Derivatives of threo-Methylphenidate (Ritalin, Concerta): Rational Design, Synthesis, Pharmacological Evaluation, and Dopamine Transporter Photoaffinity Labeling

    OpenAIRE

    Lapinsky, David J.; Velagaleti, Ranganadh; Yarravarapu, Nageswari; Liu, Yi; Huang, Yurong; Surratt, Christopher K.; Lever, John R.; Foster, James D.; Acharya, Rejwi; Vaughan, Roxanne A.; Deutsch, Howard M.

    2010-01-01

    In contrast to tropane-based compounds such as benztropine and cocaine, non-tropane-based photoaffinity ligands for the dopamine transporter (DAT) are relatively unexplored. Towards addressing this knowledge gap, ligands were synthesized in which the piperidine nitrogen of 3- and 4-iodomethylphenidate was substituted with a benzyl group bearing a photoreactive azide. Analog (...

  17. SiO2-Cu2O:An efficient and recyclable heterogeneous catalyst for N-benzylation of primary and secondary amines

    Institute of Scientific and Technical Information of China (English)

    Manjulla Gupta; Satya Paul; Rajive Gupta

    2014-01-01

    A mild, effective, and selective procedure is reported for the mono N-benzylation and N,N- diben-zylation of primary amines as well as mono N-benzylation of secondary amines using sili-ca-supported copper(I) oxide in water. The silica-supported Cu2O was generated in situ by the reac-tion of Fehling solution and glucose at 100 °C onto activated silica. The catalyst was filtered, washed with water, and oven-dried, and was characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, transmission electron microscopy, and atomic absorption spectroscopy. The prepared Cu2O-SiO2 was found to be thermally stable up to 325 °C. The copper was uniformly distributed onto the surface of the silica, and the mean particle diameter was 7 nm. The catalyst served as a selective heterogenous catalyst for the N-benzylation of primary and secondary amines. The catalyst is recyclable and was used effectively upto fifth run without a significant loss of catalytic activity. Various reaction solvents including water, acetonitrile, and toluene were screened for N-benzylation of amines, and the success of the aqueous system highlights the low environmental impact of the procedure.

  18. Substituted thiobenzoic acid S-benzyl esters as potential inhibitors of a snake venom phospholipase A2: Synthesis, spectroscopic and computational studies

    Science.gov (United States)

    Henao Castañeda, I. C.; Pereañez, J. A.; Jios, J. L.

    2012-11-01

    4-Chlorothiobenzoic acid S-benzyl ester (I), 3-nitrothiobenzoic acid S-benzyl ester (II), 4-nitrothiobenzoic acid S-benzyl ester (III) and 4-methylthiobenzoic acid S-benzyl ester (IV) were prepared and characterized by 1H and 13C NMR, Mass spectrometry and IR spectroscopy. Quantum chemical calculations were performed with Gaussian 09 to calculate the geometric parameters and vibrational spectra. Phospholipase A2 (PLA2) was purified from Crotalus durissus cumanensis venom by molecular exclusion chromatography, followed by reverse phase-high performance liquid chromatography. Two studies of the inhibition of phospholipase A2 activity were performed using phosphatidilcholine and 4-nitro-3-octanoyloxybenzoic acid as substrates, in both cases compound II showed the best inhibitory ability, with 74.89% and 69.91% of inhibition, respectively. Average percentage of inhibition was 52.49%. Molecular docking was carried out with Autodock Vina using as ligands the minimized structures of compounds (I-IV) and as protein PLA2 (PDB code 2QOG). The results suggest that compounds I-IV could interact with His48 at the active site of PLA2. In addition, all compounds showed Van der Waals interactions with residues from hydrophobic channel of the enzyme. This interaction would impede normal catalysis cycle of the PLA2.

  19. Effect of polyester blends in hydroentangled raw and bleached cotton nonwoven fabrics on the adsorption of alkyl-dimethyl-benzyl-ammonium chloride

    Science.gov (United States)

    The adsorption kinetics and isotherms of alkyl-dimethyl-benzyl-ammonium chloride (ADBAC), a cationic surfactant commonly employed as an antimicrobial agent, on hydroentangled nonwoven fabrics (applicable for wipes) including raw cotton, bleached cotton, and their blends with polyester (PES) were stu...

  20. Radiation Stability of Benzyl Tributyl Ammonium Chloride towards Technetium-99 Extraction - 13016

    International Nuclear Information System (INIS)

    investigate the suitability of new macro-compounds such as crown-ethers, aza-crown ethers, quaternary ammonium salts, and resorcin-arenes for the selective extraction of Tc-99 from nitric acid solutions. The selectivity of the ligand is important in evaluating potential separation processes and also the radiation stability of the molecule is essential for minimization of waste and radiolysis products. In this paper, we are reporting the extraction of TcO4- by benzyl tributyl ammonium chloride (BTBA). Experimental efforts were focused on determining the best extraction conditions by varying the ligand's matrix conditions and concentration, as well as varying the organic phase composition (i.e. diluent variation). Furthermore, the ligand has been investigated for radiation stability. The ?-irradiation was performed on the neat organic phases containing the ligand at different absorbed doses to a maximum of 200 kGy using an external Co-60 source. Post-irradiation solvent extraction measurements will be discussed. (authors)

  1. User involvement competence for radical innovation

    DEFF Research Database (Denmark)

    Lettl, Christopher

    One important market related capability for firms which seek to develop radical innovations is the competence to involve the 'right' users at the 'right' time in the 'right' form. While former studies have identified a rather passive role of users in the radical innovation process, this paper...... focuses on the involvement of such users that are in the position to play an active role as inventors and (co)-developers. A multiple case study analysis was conducted in the field of medical technology. Five radical innovation projects within four firms were selected including medical robots and computer......-assisted navigation systems. The case study analysis reveals that firms who closely interact with specific users benefit significantly for their radical innovation work. These users have a high motivation toward new solutions, are open to new technologies, possess diverse competencies, and are embedded into a very...

  2. Radicalization and the Use of Social Media

    Directory of Open Access Journals (Sweden)

    Robin Thompson

    2011-01-01

    Full Text Available The use of social media tools by individuals and organizations to radicalize individuals for political and social change has become increasingly popular as the Internet penetrates more of the world and mobile computing devices are more accessible. To establish a construct for radicalization,the power and reach of social media will be described so there is common understanding of what social media is and how it is utilized by various individuals and groups. The second section will answer the question of why social media applications are the perfect platform for the radical voice. Finally, the use of social media and its influence in radicalizing populations in Northern Africa and the Middle East during 2011 will be analyzed and recommendations proposed.

  3. Neo-liberal Governing of 'Radicals'

    DEFF Research Database (Denmark)

    Lindekilde, Lasse

    2012-01-01

    The Danish government’s counter-radicalization Action Plan of 2009 had intended and unintended effects. Primarily targeting Danish Muslims, it employs neoliberal governmentality approaches of governance through individual support and response, information and knowledge, empowerment, surveillance ...

  4. Free radical scavenging activity of papaya juice

    International Nuclear Information System (INIS)

    Papaya juice is an efficient scavenger of highly reactive hydroxyl radicals (OH radical) formed during 60Co irradiation of water. The OH anion radicals were detected by the electron spin resonance (ESR) technique of spin trapping using DMPO (5,5-dimethyl-1-pyrroline-N-oxide) or by a colorimetric assay in which salicylate is converted into polyhydroxybenzoic acids. Papaya juice is also able to quench the ESR signal of a stable free radical (TEMPOL) and the ESR signal of the DMPO-OH adduct. The active substance(s) in papaya juice are heat-stable, dialyzable, and soluble in water but not in lipid solvents. The active agents do not appear to be ascorbate, tocopherol, or carotenoids. (author)

  5. RADICALLY CONTESTED ASSERTIONS IN ECOSYSTEM MANAGEMENT

    Science.gov (United States)

    Ecosystem management is a magnet for controversy, in part because some of its formulations rest on questionable assertions that are radically contested. These assertions are important to understanding much of the conflict surrounding ecosystem management and, therrefore, deserve...

  6. Customers as Partners in Radical Service Innovation

    DEFF Research Database (Denmark)

    Scupola, Ada; Nicolajsen, Hanne Westh

    2009-01-01

    ongoing collaboration where creativity and trial and error are crucial. These needs require new ways of communicating and interacting between customer and consultants. Originality/value- This article is original because it generates new insights into conditions and challenges in radical innovations in......  Purpose- The main purpose of this paper is to investigate customer involvement and related challenges in radical service innovations in engineering consulting services Design/methodology/approach - The paper uses a case study approach and so called rich descriptions to investigate customer...... involvement, roles and related challenges and conditions in radical service innovations.Findings- One main finding is that customers can engage in radical service innovations in engineering consultancy services and may play a decisive role. In doing this they most likely take on all the three user involvement...

  7. A radical approach to asperparaline C

    Czech Academy of Sciences Publication Activity Database

    Amatov, Tynchtyk; Jahn, Ullrich

    Praha: Czech Chemical Society, 2015. s. 41. [Liblice 2015. Advances in Organic, Bioorganic and Pharmaceutical Chemistry /50./. 06.11.2015-08.11.2015, Olomouc] Institutional support: RVO:61388963 Keywords : asperparalines * bridged diketopiperazines * radical reactions Subject RIV: CC - Organic Chemistry

  8. Innovation Type, Radicalness, and the Adoption Process.

    Science.gov (United States)

    Damanpour, Fariborz

    1988-01-01

    Reviews studies on the impact of organizational factors on the adoption of innovations along three dimensions (innovation type, innovation radicalness, and stages of adoption), finding considerable agreement. Proposes a research agenda for future studies. (SR)

  9. Rigid Ideals and Radicals of Ore Extensions

    Institute of Scientific and Technical Information of China (English)

    Chan Yong Hong; Tai Keun Kwak; S. Tariq Rizvi

    2005-01-01

    For an endomorphism σ of a ring R, Krempa called σ a rigid endomorphism if aσ(a) = 0 implies a= 0 for a ∈ R. A ring R is called rigid if there exists a rigid endomorphism of R. In this paper, we extend the σ-rigid property of a ring R to an ideal of R. For a σ-ideal Ⅰ of a ring R, we call Ⅰ a σ-rigid ideal if aσ(a) ∈Ⅰ implies a ∈Ⅰ for a ∈ R. We characterize σ-rigid ideals and study related properties. The connections of the prime radical and the upper nil radical of R with the prime radical and the upper nil radical of the Ore extension R[x; σ, δ], respectively, are also investigated.

  10. Fast beam studies of free radical photodissociation

    Energy Technology Data Exchange (ETDEWEB)

    Neumark, D.M. [Lawrence Berkeley Laboratory, CA (United States)

    1993-12-01

    The authors have developed a novel technique for studying the photodissociation spectroscopy and dynamics of free radicals. In these experiments, radicals are generated by laser photodetachment of a fast (6-8 keV) mass-selected negative ion beam. The resulting radicals are photodissociated with a second laser, and the photofragments are collected and detected with high efficiency using a microchannel plate detector. The overall process is: ABC{sup -} {yields} ABC + e{sup -} {yields} A + BC, AB + C. Two types of fragment detection schemes are used. To map out the photodissociation cross-section of the radical, the photodissociation laser is scanned and the total photofragment yield is measured as a function of wavelength. In other experiments, the photodissociation frequency is fixed and the photofragment masses, kinetic energy release, and scattering angle is determined for each photodissociation event.

  11. Crystal structure of 3-O-benzyl-4(R-C-(1-benzyl-1H-1,2,3-triazol-4-yl-1,2-O-isopropylidene-α-d-erythrofuranose

    Directory of Open Access Journals (Sweden)

    Nikita Semjonovs

    2015-12-01

    Full Text Available The title compound, C23H25N3O4, {systematic name: 1-benzyl-4-[(3aR,5R,6R,6aR-6-benzyloxy-2,2-dimethyltetrahydrofuro[2,3-d][1,3]dioxol-5-yl]-1H-1,2,3-triazole}, consists of a substituted 2,2-dimethyltetrahydrofuro[2,3-d][1,3]dioxole. The furanose ring adopts an envelope conformation close to C3-exo, where the C atom substituted by the benzyloxy group is the flap. The fused dioxolane ring also adopts an envelope conformation, with the methylene C atom as the flap. In the crystal, molecules are linked by weak C—H...O hydrogen bonds, forming zigzag chains along [010].

  12. Free radical reactions with subtilisin Carlsberg

    International Nuclear Information System (INIS)

    Pulse radiolysis has been used to study the mechanisms of radiation-induced inactivation of enzymes. However, interpretation of the results is often complicated by the fact that the G values for enzyme inactivation are usually much smaller than the G values for the radicals formed from water radiolysis. Where inactivation by oxidative free radical attack is concerned, the problem can often be greatly simplified by the use of the free radical probe technique. These free radicals, which include the halide-type radicals Cl2-, Br2-,I2- and (CNS)2-, react much more selectively than OH radicals with amino acids. They can be used to demonstrate that selective oxidation of certain amino acid residues can lead to enzyme inactivation. The technique assists, therefore, in determining whether such sensitive amino acids are present in the active centre and are crucial to the activity of the protein. A number of enzymes have been studied by this method and the amino acid residues found to be necessary for enzymic activitya are in agreement with those identified by conventional biochemical techniques. In these enzymes, free radical attack by the halide radicals leads to inactivation by damage to a single type of amino acid residue which is involved either in catalysis or binding of the substrate. Subtilisin Carlsberg is a serine protease consisting of a poly-peptide chain lacking both cysteine and cystine residues. This paper indicates the use of the selective probe technique in demonstrating that damage to one or more histidine residues leads to inactivation of the enzyme. (author)

  13. Radicalization and the Use of Social Media

    OpenAIRE

    Robin Thompson

    2011-01-01

    The use of social media tools by individuals and organizations to radicalize individuals for political and social change has become increasingly popular as the Internet penetrates more of the world and mobile computing devices are more accessible. To establish a construct for radicalization,the power and reach of social media will be described so there is common understanding of what social media is and how it is utilized by various individuals and groups. The second section will answer the q...

  14. Modelling of tropospheric ozone and radical chemistry

    OpenAIRE

    Burkert, Jörn

    2003-01-01

    This work describes in detail the photochemistry of ozone and radicals in both remote clean air and heavily polluted regions. The results of two field studies are presented: the Indian Ocean Experiment (INDOEX) and the Peroxy Radical Initiative for Measurements in the Environment (PRIME).The :b:INDOEX:/b: campaign studied the chemistry of remote areas of the Indian Ocean and the influence of the outflow from the Indian subcontinent on these regions. Measurements of trace gases (NMHC, O3, RO2*...

  15. Free Radicals, Antioxidants in Disease and Health

    OpenAIRE

    Pham-Huy, Lien Ai; He, Hua; Pham-Huy, Chuong

    2008-01-01

    Free radicals and oxidants play a dual role as both toxic and beneficial compounds, since they can be either harmful or helpful to the body. They are produced either from normal cell metabolisms in situ or from external sources (pollution, cigarette smoke, radiation, medication). When an overload of free radicals cannot gradually be destroyed, their accumulation in the body generates a phenomenon called oxidative stress. This process plays a major part in the development of chronic and degene...

  16. The stabilization energies of polyenyl radicals

    Science.gov (United States)

    Luo, Yu-Ran; Holmes, John L.

    1994-10-01

    The resonance stabilization energies, Es, of polyenyl radicals can be estimated by the equation Es( N)=-13.2+[3.95-15.8(2) -2/ n] kcal mol -1, where N is the number of C, C-π bonds in the polyenyl radicals. This correlation has been extended for predicting the weakest HC, CC and COH bond dissociation energies in vitamin A and similar compounds.

  17. OUR 6-YEAR EXPERIENCE IN RADICAL CYSTECTOMY

    OpenAIRE

    Cevdet Kaya; Orhan Koca; Muzaffer Oğuz Keleş; Gülhan Yılmaz; Metin Öztürk; Hüseyin Kanberoğlu; M. İhsan Karaman

    2009-01-01

    Objective: Bladder cancer is the second most common cancer of the urinary tract. Radical cystectomy and urinary diversion is the gold standard treatment model of invasive bladder cancer.Patient and Methods: We evaluated 71 patients who underwent radical cystectomy, retrospectively according to their demographic properties, pre-operative and post-operative pathologies and method of urinary diversion and the complications between January 2003 and 2008.Results: Mean follow-up was 28.8 months aft...

  18. Project Radicalization: Why do "they" hate "us"?

    OpenAIRE

    Eggert, Lasse; Foged, Mathias; Jensen, Martin

    2014-01-01

    The phenomenon of global terrorism is still not fully understood by the international community whether within the contingents of public decision-makers, security agencies and researchers. Radicalization as explanation and analytical tool for understanding terrorism has relatively recently gained new prominence. In this project the question of which discourses can be found in the scientific material within the research field of terrorism and radicalization is addressed. A sample of scientifi...

  19. Control of radical chemistry in the AdoMet-radical enzymes

    OpenAIRE

    Duschene, Kaitlin S.; Veneziano, Susan E.; Silver, Sunshine C.; Broderick, Joan B.

    2009-01-01

    The radical AdoMet superfamily comprises a diverse set of >2800 enzymes that utilize iron-sulfur clusters and S-adenosylmethionine (SAM or AdoMet) to initiate a diverse set of radical-mediated reactions. The intricate control these enzymes exercise over the radical transformations they catalyze is an amazing feat of elegance and sophistication in biochemistry. This review focuses on the accumulating evidence for how these enzymes control this remarkable chemistry, including controlling the re...

  20. Reactions of alkoxy radicals in aqueous solutions

    International Nuclear Information System (INIS)

    The kinetic and mechanistic properties of alkoxy radicals in organic solvents are briefly reviewed. Owing to the scarcity of such data in aqueous solutions and since reactions at the membrane/water interface may be also biologically important, we have studied the reactivity of these radicals in water and the results of our investigations are reported. Alkoxy radicals were generated by photolytic or radiolytic cleavage of peroxide precursors (tert-butyl hydroperoxide and di-tert-butyl peroxide as well as hydroperoxides of polyunsaturated fatty acids). A quantitative correlation between the structure of various substances, in particular, phenolic antioxidants, and their activity in inhibiting the alkoxy radical-induced bleaching of the water-soluble carotenoid crocin will be discussed. Rate constants for intermolecular reactions of t-BuO. radicals were determined by pulse radiolysis. The diffusion-controlled reaction with the catechol antioxidant nordihydroguaiaretic acid demonstrates an effective competition with the very rapid intra molecular β-fragmentation in water. The results aupport the view that a considerable amount of alkoxy radicals interact with substrates before they can rearrange intramolecularly

  1. Reactions of alkoxy radicals in aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Bors, W.; Tait, D.; Michel, C.; Saran, M.; Erben-Russ, M. (Gesellschaft fuer Strahlen- und Umweltforschung m.b.H. Muenchen, Neuherberg (Germany, F.R.). Abt. fuer Strahlenbiologie)

    1984-01-01

    The kinetic and mechanistic properties of alkoxy radicals in organic solvents are briefly reviewed. Owing to the scarcity of such data in aqueous solutions and since reactions at the membrane/water interface may be also biologically important, we have studied the reactivity of these radicals in water and the results of our investigations are reported. Alkoxy radicals were generated by photolytic or radiolytic cleavage of peroxide precursors (tert-butyl hydroperoxide and di-tert-butyl peroxide as well as hydroperoxides of polyunsaturated fatty acids). A quantitative correlation between the structure of various substances, in particular, phenolic antioxidants, and their activity in inhibiting the alkoxy radical-induced bleaching of the water-soluble carotenoid crocin will be discussed. Rate constants for intermolecular reactions of t-BuO. radicals were determined by pulse radiolysis. The diffusion-controlled reaction with the catechol antioxidant nordihydroguaiaretic acid demonstrates an effective competition with the very rapid intra molecular ..beta..-fragmentation in water. The results aupport the view that a considerable amount of alkoxy radicals interact with substrates before they can rearrange intramolecularly.

  2. Inactivation of Bacillus atrophaeus by OH radicals

    Science.gov (United States)

    Ono, Ryo; Yonetamari, Kenta; Tokumitsu, Yusuke; Yonemori, Seiya; Yasuda, Hachiro; Mizuno, Akira

    2016-08-01

    The inactivation of Bacillus atrophaeus by OH radicals is measured. This study aims to evaluate the bactericidal effects of OH radicals produced by atmospheric-pressure nonthermal plasma widely used for plasma medicine; however, in this study, OH radicals are produced by vacuum ultraviolet (VUV) photolysis of water vapor instead of plasma to allow the production of OH radicals with almost no other reactive species. A 172 nm VUV light from a Xe2 excimer lamp irradiates a He–H2O mixture flowing in a quartz tube to photodissociate H2O to produce OH, H, O, HO2, H2O2, and O3. The produced reactive oxygen species (ROS) flow out of the quartz tube nozzle to the bacteria on an agar plate and cause inactivation. The inactivation by OH radicals among the six ROS is observed by properly setting the experimental conditions with the help of simulations calculating the ROS densities. A 30 s treatment with approximately 0.1 ppm OH radicals causes visible inactivation.

  3. Radioprotective thermally generated free-radical dextrins

    Institute of Scientific and Technical Information of China (English)

    Piotr TOMASIK; Oskar MICHALSKI; Ewa BIDZINSKA; Antonina CEBULSKA-WASILEWSKA; Krystyna DYREK; Maciej FIEDOROWICZ; Pawel OLKO

    2008-01-01

    Effect of doses of the X-ray radiation from 0 to 400 Gy upon granular cornstarch and dextrins (British gums, BG) thermally generated from it at 230-300℃ was recognized with quantitative EPR and IR ab-sorption spectroscopy, molecular mass distribution in the depolymerization products, Scanning Elec-tron Microscopy, and X-ray diffractometry. Fractal analysis of the profiles of molecular mass distribu-tion showed that the depolymerization involved debranching of amylopectin. Roasting of cornstarch produced BG which differed in concentration and EPR parameters of stable free radicals from BG generated by X-ray radiation. Two types of stable free radicals, with Gaussian and Lorentzian shapes of EPR signals, were recognized. The shapes of the signals and temperature dependence on free radical intensity indicated exchanging interactions of the antiferromagnetic type, causing partial quenching of the spins at -196℃ (77K). Upon X-ray irradiation, new radicals were generated, the number and stability of which strongly depended on the types of radicals present before irradiation. These radicals slowly ceased because of a repolymerization of BG on storage.

  4. High efficient photocatalytic selective oxidation of benzyl alcohol to benzaldehyde by solvothermal-synthesized ZnIn{sub 2}S{sub 4} microspheres under visible light irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zhixin, E-mail: czx@fzu.edu.cn [State Key Laboratory Breeding Base of Photocatalysis, College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350002 (China); Instrumental Measurement and Analysis Center, Fuzhou University, Fuzhou 350002 (China); Xu, Jingjing; Ren, Zhuyun [State Key Laboratory Breeding Base of Photocatalysis, College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350002 (China); He, Yunhui; Xiao, Guangcan [State Key Laboratory Breeding Base of Photocatalysis, College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350002 (China); Instrumental Measurement and Analysis Center, Fuzhou University, Fuzhou 350002 (China)

    2013-09-15

    Hexagonal ZnIn{sub 2}S{sub 4} samples have been synthesized by a solvothermal method. Their properties have been determined by X-ray diffraction, ultraviolet–visible-light diffuse reflectance spectra, field emission scanning electron microscopy, nitrogen adsorption–desorption and X-ray photoelectron spectra. These results demonstrate that ethanol solvent has significant influence on the morphology, optical and electronic nature for such marigold-like ZnIn{sub 2}S{sub 4} microspheres. The visible light photocatalytic activities of the ZnIn{sub 2}S{sub 4} have been evaluated by selective oxidation of benzyl alcohol to benzaldehyde using molecular oxygen as oxidant. The results show that 100% conversion along with >99% selectivity are reached over ZnIn{sub 2}S{sub 4} prepared in ethanol solvent under visible light irradiation (λ>420 nm) of 2 h, but only 58% conversion and 57% yield are reached over ZnIn{sub 2}S{sub 4} prepared in aqueous solvent. A possible mechanism of the high photocatalytic activity for selective oxidation of benzyl alcohol over ZnIn{sub 2}S{sub 4} is proposed and discussed. - Graphical abstract: Marigold-like ZnIn{sub 2}S{sub 4} microspheres were synthesized by a solvothermal method. The high visible photocatalytic activities of ZnIn{sub 2}S{sub 4} were evaluated by selective oxidation of benzyl alcohol to benzaldehyde under mild conditions. Display Omitted - Highlights: • Marigold-like ZnIn{sub 2}S{sub 4} microspheres were synthesized by a solvothermal method. • The solvents have a remarkably influence on the morphology and properties of samples. • It is the first time to apply ZnIn{sub 2}S{sub 4} for selective oxidation of benzyl alcohol. • ZnIn{sub 2}S{sub 4} shows high photocatalytic activity for selective oxidation of benzyl alcohol.

  5. High efficient photocatalytic selective oxidation of benzyl alcohol to benzaldehyde by solvothermal-synthesized ZnIn2S4 microspheres under visible light irradiation

    International Nuclear Information System (INIS)

    Hexagonal ZnIn2S4 samples have been synthesized by a solvothermal method. Their properties have been determined by X-ray diffraction, ultraviolet–visible-light diffuse reflectance spectra, field emission scanning electron microscopy, nitrogen adsorption–desorption and X-ray photoelectron spectra. These results demonstrate that ethanol solvent has significant influence on the morphology, optical and electronic nature for such marigold-like ZnIn2S4 microspheres. The visible light photocatalytic activities of the ZnIn2S4 have been evaluated by selective oxidation of benzyl alcohol to benzaldehyde using molecular oxygen as oxidant. The results show that 100% conversion along with >99% selectivity are reached over ZnIn2S4 prepared in ethanol solvent under visible light irradiation (λ>420 nm) of 2 h, but only 58% conversion and 57% yield are reached over ZnIn2S4 prepared in aqueous solvent. A possible mechanism of the high photocatalytic activity for selective oxidation of benzyl alcohol over ZnIn2S4 is proposed and discussed. - Graphical abstract: Marigold-like ZnIn2S4 microspheres were synthesized by a solvothermal method. The high visible photocatalytic activities of ZnIn2S4 were evaluated by selective oxidation of benzyl alcohol to benzaldehyde under mild conditions. Display Omitted - Highlights: • Marigold-like ZnIn2S4 microspheres were synthesized by a solvothermal method. • The solvents have a remarkably influence on the morphology and properties of samples. • It is the first time to apply ZnIn2S4 for selective oxidation of benzyl alcohol. • ZnIn2S4 shows high photocatalytic activity for selective oxidation of benzyl alcohol

  6. Radicalization and Radical Catalysis of Biomass Sugars: Insights from First-principles Studies

    Science.gov (United States)

    Yang, Gang; Zhu, Chang; Zou, Xianli; Zhou, Lijun

    2016-01-01

    Ab initio and density functional calculations are conducted to investigate the radicalization processes and radical catalysis of biomass sugars. Structural alterations due to radicalization generally focus on the radicalized sites, and radicalization affects H-bonds in D-fructofuranose more than in D-glucopyranose, potentially with outcome of new H-bonds. Performances of different functionals and basis sets are evaluated for all radicalization processes, and enthalpy changes and Gibbs free energies for these processes are presented with high accuracy, which can be referenced for subsequent experimental and theoretical studies. It shows that radicalization can be utilized for direct transformation of biomass sugars, and for each sugar, C rather than O sites are always preferred for radicalization, thus suggesting the possibility to activate C-H bonds of biomass sugars. Radical catalysis is further combined with Brønsted acids, and it clearly states that functionalization fundamentally regulates the catalytic effects of biomass sugars. In presence of explicit water molecules, functionalization significantly affects the activation barriers and reaction energies of protonation rather than dehydration steps. Tertiary butyl and phenyl groups with large steric hindrances or hydroxyl and amino groups resulting in high stabilities for protonation products drive the protonation steps to occur facilely at ambient conditions. PMID:27405843

  7. Radicalization and Radical Catalysis of Biomass Sugars: Insights from First-principles Studies

    Science.gov (United States)

    Yang, Gang; Zhu, Chang; Zou, Xianli; Zhou, Lijun

    2016-07-01

    Ab initio and density functional calculations are conducted to investigate the radicalization processes and radical catalysis of biomass sugars. Structural alterations due to radicalization generally focus on the radicalized sites, and radicalization affects H-bonds in D-fructofuranose more than in D-glucopyranose, potentially with outcome of new H-bonds. Performances of different functionals and basis sets are evaluated for all radicalization processes, and enthalpy changes and Gibbs free energies for these processes are presented with high accuracy, which can be referenced for subsequent experimental and theoretical studies. It shows that radicalization can be utilized for direct transformation of biomass sugars, and for each sugar, C rather than O sites are always preferred for radicalization, thus suggesting the possibility to activate C-H bonds of biomass sugars. Radical catalysis is further combined with Brønsted acids, and it clearly states that functionalization fundamentally regulates the catalytic effects of biomass sugars. In presence of explicit water molecules, functionalization significantly affects the activation barriers and reaction energies of protonation rather than dehydration steps. Tertiary butyl and phenyl groups with large steric hindrances or hydroxyl and amino groups resulting in high stabilities for protonation products drive the protonation steps to occur facilely at ambient conditions.

  8. Control of radical chemistry in the AdoMet-radical enzymes

    Science.gov (United States)

    Duschene, Kaitlin S.; Veneziano, Susan E.; Silver, Sunshine C.; Broderick, Joan B.

    2009-01-01

    Summary The radical AdoMet superfamily comprises a diverse set of >2800 enzymes that utilize iron-sulfur clusters and S-adenosylmethionine (SAM or AdoMet) to initiate a diverse set of radical-mediated reactions. The intricate control these enzymes exercise over the radical transformations they catalyze is an amazing feat of elegance and sophistication in biochemistry. This review focuses on the accumulating evidence for how these enzymes control this remarkable chemistry, including controlling the reactivity between the iron-sulfur cluster and AdoMet, and controlling the subsequent radical transformations. PMID:19269883

  9. Control of radical chemistry in the AdoMet radical enzymes.

    Science.gov (United States)

    Duschene, Kaitlin S; Veneziano, Susan E; Silver, Sunshine C; Broderick, Joan B

    2009-02-01

    The radical AdoMet superfamily comprises a diverse set of >2800 enzymes that utilize iron-sulfur clusters and S-adenosylmethionine (SAM or AdoMet) to initiate a diverse set of radical-mediated reactions. The intricate control these enzymes exercise over the radical transformations they catalyze is an amazing feat of elegance and sophistication in biochemistry. This review focuses on the accumulating evidence for how these enzymes control this remarkable chemistry, including controlling the reactivity between the iron-sulfur cluster and AdoMet, and controlling the subsequent radical transformations. PMID:19269883

  10. Structure of HIV-1 nonnucleoside reverse transcriptase inhibitors derivatives of N-benzyl-benzimidazole with different substituents in position 4

    Science.gov (United States)

    Ziółkowska, Natasza E.; Michejda, Christopher J.; Bujacz, Grzegorz D.

    2010-01-01

    The constant development of new drugs against HIV-1 is necessary due to global expansion of AIDS and HIV-1 drug resistance. Nonnucleoside reverse transcriptase inhibitors of HIV-1 (NNRTIs) are potentially effective and nontoxic drugs in AIDS therapy. The crystal structures of six nonnucleoside inhibitors of HIV-1 reverse transcriptase (RT) derivatives of N-benzyl-benzimidazole are reported here. The investigated compounds belong to the group of so called "butterfly like" inhibitors with characteristic two π-electron moieties with an angled orientation. The structural data show the influence of the substituents of the benzimidazole ring on the geometry of the molecule and correlation between the structure of the inhibitor and its biological activity.

  11. 1-Benzyl-1H-benzotriazole 3-oxide–1-hydroxy-1H-benzotriazole (1/1

    Directory of Open Access Journals (Sweden)

    P. Selvarathy Grace

    2012-08-01

    Full Text Available In the title compound, C6H5N3O·C13H11N3O, the benzotriazole ring system in the 1-benzyl-1H-benzotriazole 3-oxide (A molecule is close to being planar (r.m.s. deviation = 0.011 Å; its mean plane forms a dihedral angle of 67.56 (7° with that of the attached phenyl ring. The benzotriazole ring system in the 1-hydroxybenzotriazole (B molecule is also close to being planar (r.m.s. deviation = 0.010 Å. In the crystal, weak C—H...O and C—H...π interactions are present. The A and B molecules are linked by an O—H...N hydrogen bond.

  12. 1-Benzyl-2-Phenylbenzimidazole (BPB, a Benzimidazole Derivative, Induces Cell Apoptosis in Human Chondrosarcoma through Intrinsic and Extrinsic Pathways

    Directory of Open Access Journals (Sweden)

    Ju-Fang Liu

    2012-12-01

    Full Text Available In this study, we investigated the anticancer effects of a new benzimidazole derivative, 1-benzyl-2-phenyl -benzimidazole (BPB, in human chondrosarcoma cells. BPB-mediated apoptosis was assessed by the MTT assay and flow cytometry analysis. The in vivo efficacy was examined in a JJ012 xenograft model. Here we found that BPB induced apoptosis in human chondrosarcoma cell lines (JJ012 and SW1353 but not in primary chondrocytes. BPB induced upregulation of Bax, Bad and Bak, downregulation of Bcl-2, Bid and Bcl-XL and dysfunction of mitochondria in chondrosarcoma. In addition, BPB also promoted cytosolic releases AIF and Endo G. Furthermore, it triggered extrinsic death receptor-dependent pathway, which was characterized by activating Fas, FADD and caspase-8. Most importantly, animal studies revealed a dramatic 40% reduction in tumor volume after 21 days of treatment. Thus, BPB may be a novel anticancer agent for the treatment of chondrosarcoma.

  13. Influence of Preparation Methods of Nano Au/MCM-41 Catalysts for Vapor Phase Oxidation of Benzyl Alcohol.

    Science.gov (United States)

    Kumar, Ashish; Kumar, Vanama Pavan; Vishwanathan, Venkataraman; Chary, V R

    2015-12-01

    The Au/MCM-41 nano catalysts were synthesized from four different methods, viz., homogeneous deposition-precipitation, micro-emulsion, impregnation and polyol and their catalytic activities were tested for the vapor phase oxidation of benzyl alcohol to benzaldehyde. The physico-chemical properties of the catalysts were investigated by XRD, TEM, BET surface area, PSD, CO-chemisorption and XPS techniques. The effect of preparation methods, nature of the metal, support and the metal-support interaction in Au/MCM-41 catalysts were studied for the title reaction. The Au/MCM-41 catalysts synthesized from HDP method has shown higher and better catalytic activity as compared to the catalysts prepared by other methods. PMID:26682438

  14. Crystal structure of hydrazine 5-amino-1-benzyl-1,2,3-triazole-4-carboxylate hexafluorosilicate trihydrate

    International Nuclear Information System (INIS)

    Hydrazine 5-amino-1-benzyl-1,2,3-triazole-4-carboxylate hexafluorosilicate trihydrate (I) is synthesized. The crystal structure of the compound synthesized is determined. Crystals I are monoclinic, a 13.353(1) A, b = 21.094(2) A, c = 20.233(2) A, β = 94.05(3) deg., space group P21/c, and R = 0.0584 for 16 601 reflections with I > 2σ(I). In the asymmetric part of the unit cell, four organic cations protonated at the terminal hydrazine nitrogen atoms, two hexafluorosilicate anions, and six water molecules are linked into a three-dimensional framework through hydrogen bonds of the N-H···F, N-H···O, and O-H···F types

  15. Polymer-clay nanocomposites obtained by solution polymerization of vinyl benzyl triammonium chloride in the presence of advanced functionalized clay

    Indian Academy of Sciences (India)

    Raluca Ianchis; Dan Donescu; Ludmila Otilia Cinteza; Violeta Purcar; Cristina Lavinia Nistor; Critian Petcu; Cristian Andi Nicolae; Raluca Gabor; Silviu Preda

    2014-05-01

    Polymer-clay nanocomposites were synthesized by solution polymerization method using advanced functionalized clay and vinyl benzyl trimethyl ammonium chloride as monomer. First stage consisted in the silylation of a commercial organo-modified clay-Cl 20A using alkoxysilanes with different chain lengths. In the second step, the synthesis and characterization of polymer-nanocomposites were followed. To evaluate the clay functionalization process as well as the final polymer-clay products, thermogravimetric,X-ray diffraction, dynamic light scattering, Fourier transform infrared spectroscopy and three test liquid contact angles analyses were used. The loss of ammonium ions from commercial clay, the grafting degree, the lengths and the nature of alkyl chain influence the dispersion of the advanced modified clay into the polymer solution and, furthermore, the properties of the final polymer-clay nanocomposite film.

  16. Synthesis and Crystal Structure of N-Benzyl-N'-(2-pyridyl)urea and Its Mononuclear Cu(II) Complex

    Institute of Scientific and Technical Information of China (English)

    HE Lei; LUO Xiao-Lan; ZHANG Wen-Qin

    2008-01-01

    A new ligand of N-benzyl-N'-(2-pyridyl)urea L and its self-assembly product with CuCl2, [Cu(II)LCl2]∞ 1, have been synthesized and structurally characterized by IR, 1H NMR and single-crystal X-ray diffraction analysis. In the structure of L, the urea groups adopt Z,E conformation to form dimers through intermolecular hydrogen bonds; while in complex 1, it assumes Z,Z conformation to fit for the coordination sphere of the Cu(II) ions. The coordinated units are connected through intermolecular N-H…Cl hydrogen bonds to form an extended 2D framework. Finally, a 3D structure is obtained via π-π stacking interactions between pyridyl rings.

  17. 5,6-Dimethoxybenzofuran-3-one Derivatives: a Novel Series of Dual Acetylcholinesterase/Butyrylcholinesterase Inhibitors Bearing Benzyl Pyridinium Moiety

    Directory of Open Access Journals (Sweden)

    Mohammad Abdollahi

    2013-02-01

    Full Text Available Several studies have been focused on design and synthesis of multi-target anti Alzheimer compounds. Utilizing of the dual Acetylcholinesterase/Butyrylcholinesterase inhibitors has gained more interest to treat the Alzheimer’s disease. As a part of a research program to find a novel drug for treating Alzheimer disease, we have previously reported 6-alkoxybenzofuranone derivatives as potent acetylcholinesterase inhibitors. In continuation of our work, we would like to report the synthesis of 5,6-dimethoxy benzofuranone derivatives bearing a benzyl pyridinium moiety as dual Acetylcholinesterase/Butyrylcholinesterase inhibitors.MethodsThe synthesis of target compounds was carried out using a conventional method. Bayer-Villiger oxidation of 3,4-dimethoxybenzaldehyde furnished 3,4-dimethoxyphenol. The reaction of 3,4-dimethoxyphenol with chloroacetonitrile followed by treatment with HCl solution and then ring closure yielded the 5,6-dimethoxy benzofuranone. Condensation of the later compound with pyridine-4-carboxaldehyde and subsequent reaction with different benzyl halides afforded target compounds. The biological activity was measured using standard Ellman’s method. Docking studies were performed to get better insight into interaction of compounds with receptor.ResultsThe in vitro anti acetylcholinesterase/butyrylcholinesterase activity of compounds revealed that, all of the target compounds have good inhibitory activity against both Acetylcholinesterase/Butyrylcholinesterase enzymes in which compound 5b (IC50 = 52 ± 6.38nM was the most active compound against acetylcholinesterase. The same binding mode and interactions were observed for the reference drug donepezil and compound 5b in docking study.ConclusionsIn this study, we presented a new series of benzofuranone-based derivatives having pyridinium moiety as potent dual acting Acetylcholinesterase/Butyrylcholinesterase inhibitors.

  18. Experimental density, viscosity, interfacial tension and water solubility of ethyl benzene-α-methyl benzyl alcohol–water system

    International Nuclear Information System (INIS)

    Highlights: • Properties were measured for MBA (methyl benzyl alcohol)-EB (ethyl benzene)-water. • MBA concentration was found to influence all the properties strongly. • The water solubility, density, and viscosity increased at high MBA concentration. • The interfacial tension decreased sharply at high MBA concentration. • MBA dictates the phase separation and mass transfer of the ternary system. -- Abstract: Density, viscosity, interfacial tension, and water solubility were measured for the (α-methyl benzyl alcohol (MBA) + Ethyl benzene (EB)) system at different concentrations of MBA in contact with water and sodium hydroxide solution (0.01 mol · kg−1) as aqueous phases. The properties were measured to identify the component which plays a governing role in changing the physical properties relevant to mass transfer and phase separation of the ternary system. The concentration of MBA was found to be the major factor influencing all the properties. The water solubility, the density, and the viscosity increased notably at higher concentrations of MBA; while, the interfacial tension decreased strongly. The use of 0.01 mol · kg−1 NaOH as an aqueous phase resulted in a decrease of the interfacial tension and a minor decrease in the water solubility. The density data were correlated using a quadratic mixing rule to describe the influence of concentration at any temperature. The viscosity data are correlated using the Nissan and Grunberg and Katti-Chaudhri equations. The Szyzkowski’s equation was used to correlate the interfacial tension data. The water solubility data were described using an exponential relationship. All the correlations described the experimental physical property data adequately

  19. ESR study on carboxymethyl chitosan radicals in an aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Saiki, Seiichi, E-mail: saiki.seiichi@jaea.go.j [Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Quantum Beam Science Directorate, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Nagasawa, Naotsugu; Hiroki, Akihiro; Morishita, Norio; Tamada, Masao [Quantum Beam Science Directorate, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Muroya, Yusa; Kudo, Hisaaki [Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Katsumura, Yosuke [Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Advanced Science Research Center, Japan Atomic Energy Agency, 2-4 Shirakata-Shirane, Tokai, Naka, Ibaraki 319-1195 (Japan)

    2010-03-15

    Carboxymethyl chitosan (CMCTS) at a highly concentrated aqueous solution forms hydrogel by ionizing irradiation. To study on radiation-induced reaction mechanism of CMCTS in an aqueous solution, CMCTS radicals formed by reactions with OH radical were observed by ESR method. As a result of ESR spectral analysis, CMCTS radicals were identified as radicals on carboxymethyl groups.

  20. Modeling Radicalization Phenomena in Heterogeneous Populations.

    Science.gov (United States)

    Galam, Serge; Javarone, Marco Alberto

    2016-01-01

    The phenomenon of radicalization is investigated within a mixed population composed of core and sensitive subpopulations. The latest includes first to third generation immigrants. Respective ways of life may be partially incompatible. In case of a conflict core agents behave as inflexible about the issue. In contrast, sensitive agents can decide either to live peacefully adjusting their way of life to the core one, or to oppose it with eventually joining violent activities. The interplay dynamics between peaceful and opponent sensitive agents is driven by pairwise interactions. These interactions occur both within the sensitive population and by mixing with core agents. The update process is monitored using a Lotka-Volterra-like Ordinary Differential Equation. Given an initial tiny minority of opponents that coexist with both inflexible and peaceful agents, we investigate implications on the emergence of radicalization. Opponents try to turn peaceful agents to opponents driving radicalization. However, inflexible core agents may step in to bring back opponents to a peaceful choice thus weakening the phenomenon. The required minimum individual core involvement to actually curb radicalization is calculated. It is found to be a function of both the majority or minority status of the sensitive subpopulation with respect to the core subpopulation and the degree of activeness of opponents. The results highlight the instrumental role core agents can have to hinder radicalization within the sensitive subpopulation. Some hints are outlined to favor novel public policies towards social integration. PMID:27166677

  1. Modeling Radicalization Phenomena in Heterogeneous Populations.

    Directory of Open Access Journals (Sweden)

    Serge Galam

    Full Text Available The phenomenon of radicalization is investigated within a mixed population composed of core and sensitive subpopulations. The latest includes first to third generation immigrants. Respective ways of life may be partially incompatible. In case of a conflict core agents behave as inflexible about the issue. In contrast, sensitive agents can decide either to live peacefully adjusting their way of life to the core one, or to oppose it with eventually joining violent activities. The interplay dynamics between peaceful and opponent sensitive agents is driven by pairwise interactions. These interactions occur both within the sensitive population and by mixing with core agents. The update process is monitored using a Lotka-Volterra-like Ordinary Differential Equation. Given an initial tiny minority of opponents that coexist with both inflexible and peaceful agents, we investigate implications on the emergence of radicalization. Opponents try to turn peaceful agents to opponents driving radicalization. However, inflexible core agents may step in to bring back opponents to a peaceful choice thus weakening the phenomenon. The required minimum individual core involvement to actually curb radicalization is calculated. It is found to be a function of both the majority or minority status of the sensitive subpopulation with respect to the core subpopulation and the degree of activeness of opponents. The results highlight the instrumental role core agents can have to hinder radicalization within the sensitive subpopulation. Some hints are outlined to favor novel public policies towards social integration.

  2. Modeling Radicalization Phenomena in Heterogeneous Populations

    Science.gov (United States)

    2016-01-01

    The phenomenon of radicalization is investigated within a mixed population composed of core and sensitive subpopulations. The latest includes first to third generation immigrants. Respective ways of life may be partially incompatible. In case of a conflict core agents behave as inflexible about the issue. In contrast, sensitive agents can decide either to live peacefully adjusting their way of life to the core one, or to oppose it with eventually joining violent activities. The interplay dynamics between peaceful and opponent sensitive agents is driven by pairwise interactions. These interactions occur both within the sensitive population and by mixing with core agents. The update process is monitored using a Lotka-Volterra-like Ordinary Differential Equation. Given an initial tiny minority of opponents that coexist with both inflexible and peaceful agents, we investigate implications on the emergence of radicalization. Opponents try to turn peaceful agents to opponents driving radicalization. However, inflexible core agents may step in to bring back opponents to a peaceful choice thus weakening the phenomenon. The required minimum individual core involvement to actually curb radicalization is calculated. It is found to be a function of both the majority or minority status of the sensitive subpopulation with respect to the core subpopulation and the degree of activeness of opponents. The results highlight the instrumental role core agents can have to hinder radicalization within the sensitive subpopulation. Some hints are outlined to favor novel public policies towards social integration. PMID:27166677

  3. Analysis of radicals induced in irradiated foods

    International Nuclear Information System (INIS)

    By electron spin resonance (ESR) spectroscopy, we revealed free radicals in γ-ray irradiated foods; black pepper, green coffee bean and ginseng. We also analyzed the decay behavior of radiation induced free radicals during storage of irradiated foods. The ESR spectrum of experimental irradiated foods consists of a sextet signal centered at g=2.0 and a singlet signal at the same g-value position and a singlet signal at g=4.0. The singlet signal at g=2.0 is originated from organic free radicals and its peak intensity showed the dependence of γ-ray irradiation dose levels. The signal intensity was decreased during storage. Only after 3 hours of radiation treatment the peak intensity was decreased fast and after that the intensity was decreased slowly. The relaxation times, T1 and T2, of radiation induced free radicals showed the variations before and after irradiation. During long time storage period it was shown that T1 was increased and T2 was decreased. By analysis of decay process using the simulation methods based on the theory of reaction speed, it is considered that at least two kinds of radicals were induced in irradiated foods during long time storage. (author)

  4. Tuning the Reactivity of Radical through a Triplet Diradical Cu(II) Intermediate in Radical Oxidative Cross-Coupling

    Science.gov (United States)

    Zhou, Liangliang; Yi, Hong; Zhu, Lei; Qi, Xiaotian; Jiang, Hanpeng; Liu, Chao; Feng, Yuqi; Lan, Yu; Lei, Aiwen

    2015-11-01

    Highly selective radical/radical cross-coupling is paid more attention in bond formations. However, due to their intrinsic active properties, radical species are apt to achieve homo-coupling instead of cross-coupling, which makes the selective cross-coupling as a great challenge and almost untouched. Herein a notable strategy to accomplish direct radical/radical oxidative cross-coupling has been demonstrated, that is metal tuning a transient radical to a persistent radical intermediate followed by coupling with another transient radical. Here, a transient nitrogen-centered radical is tuned to a persistent radical complex by copper catalyst, followed by coupling with a transient allylic carbon-centered radical. Firstly, nitrogen-centered radical generated from N-methoxybenzamide stabilized by copper catalyst was successfully observed by EPR. Then DFT calculations revealed that a triplet diradical Cu(II) complex formed from the chelation N-methoxybenzamide nitrogen-centered radical to Cu(II) is a persistent radical species. Moreover, conceivable nitrogen-centered radical Cu(II) complex was observed by high-resolution electrospray ionization mass spectrometry (ESI-MS). Ultimately, various allylic amides derivatives were obtained in good yields by adopting this strategy, which might inspire a novel and promising landscape in radical chemistry.

  5. Free Radical Scavenging Activity of Leaves of Alocasia indica (Linn)

    OpenAIRE

    Mulla, W. A.; Salunkhe, V. R.; Kuchekar, S. B.; Qureshi, M. N.

    2009-01-01

    The free radical scavenging potential of the plant Alocasia indica(Linn.) was studied by using different antioxidant models of screening like scavenging of 1,1-diphenyl-2-picryl hydrazyl radical, nitric oxide radical, superoxide anion radical, hydroxyl radical, iron chelating activity, total antioxidant capacity, non-enzymatic glycosylation of haemoglobin, rapid screening for antioxidant compounds by thin layer chromatography. The hydroalcoholic extract at 1000 μg/ml showed maximum scavenging...

  6. Formation of semiquinone radical anion and free radical scavenging reactions of plumbagin. A pulse radiolysis study

    International Nuclear Information System (INIS)

    Kinetics and mechanism of scavenging of reducing free radicals by plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone) are studied using pulse radiolysis technique. It scavenged superoxide radical, hydroxyethyl radical and hydrated electron with bimolecular rate constants of 8.9 × 107, 2.3 × 109 and 1.6 × 1010 M-1 s-1, respectively in aqueous-alcohol medium. Plumbagin also scavenged linoleic acid peroxyl radical and tyrosyl radical with bimolecular rate constants of 1.0 × 108 and 7.0 × 106 M-1 s-1, respectively. Further, redox properties of plumbagin and its transients are studied using standard redox couples and cyclic voltammetry. (author)

  7. Isolation of Hypervalent Group-16 Radicals and Their Application in Organic-Radical Batteries.

    Science.gov (United States)

    Imada, Yasuyuki; Nakano, Hideyuki; Furukawa, Ko; Kishi, Ryohei; Nakano, Masayoshi; Maruyama, Hitoshi; Nakamoto, Masaaki; Sekiguchi, Akira; Ogawa, Masahiro; Ohta, Toshiaki; Yamamoto, Yohsuke

    2016-01-20

    Using a newly prepared tridentate ligand, we isolated hypervalent sulfur and selenium radicals for the first time and characterized their structures. X-ray crystallography, electron spin resonance spectroscopy, and density functional theory calculations revealed a three-coordinate hypervalent structure. Utilizing the reversible redox reactions between hypervalent radicals and the corresponding anions bearing Li(+), we developed organic radical batteries with these compounds as cathode-active materials. Furthermore, an all-radical battery, with these compounds as the cathode and a silyl radical as the anode, was developed that exhibited a practical discharge potential of ∼ 1.8 V and stable cycle performance, demonstrating the potential of these materials for use in metal-free batteries that can replace conventional Li-ion batteries where Li is used in the metal form. PMID:26721786

  8. Radical kinetics and characterization of the free radicals in gamma irradiated red pepper

    International Nuclear Information System (INIS)

    Kinetic behaviors and characterization of the natural and γ-induced radicals in irradiated red pepper have been investigated by electron spin resonance (ESR) spectroscopy to explore the possibility of using this technique in detecting irradiated red pepper and to evaluate the eventual dosimetric features of this widely used food. Unirradiated samples exhibited a single resonance line centered at g=2.0050±0.0005. Photo-exposure of the samples was found to increase the signal intensity. An increase in temperature created a drastic decrease in the concentration of natural radicals responsible for the single resonance line. Irradiation was observed to induce increases in the intensity of single resonance line (signal I) and a radiation specific doublet and/or triplet (signal II) also centered at g=2.0050 but detectable only at high spectrometer gains. The intensities of both signals increased with increasing radiation dose. The signals I and II were found to decay with different rates depending on the temperature. The results of a fitting procedure applied to the experimental signal decay curves and those obtained from room temperature spectra simulation calculations were used together to determine radical species and their spectral characteristics giving rise to the observed experimental spectra. Four radical species, three carbohydrate and one semiquinone radical assigned as radicals A, B, C and D, respectively, were found to best explain the experimental results. All the radicals show large g and hyperfine splitting anisotropies varying between g=2.0028-2.0062 and 1.07-2.58 mT, respectively. The half lives of the radicals were found to depend strongly on temperature. The activation energy calculated using temperature dependent half-life data were the highest for radical A (33.68 kcal/mol) and smallest for radical C (11.83 kcal/mol)

  9. Free-radical chemistry of thiourea in aqueous solution, induced by OH radical, H atom, α-hydroxyalkyl radicals, photoexcited maleimide, and the solvated electron

    International Nuclear Information System (INIS)

    Hydroxyl radicals react with thiourea (and its tetramethyl derivative) yielding dimeric radical cations which are characterized by strong absorptions at 400 nm (450 nm). An analysis of the kinetics of the buildup of these absorptions gives evidence for the intermediacy of OH-adducts and the monomeric radical cations. The dimeric radical cations are also generated in the reactions of triplet-excited maleimide with those thioureas. Moreover, in acidic solutions even reducing radicals such as the H atom and α-hydroxy alkyl radicals give rise to these intermediates in full yields, albeit displaying different kinetics. Potential mechanistic implications are discussed. The dimeric thiourea radical cations are strong oxidants and readily oxidize the anions of phenol and 2'-deoxyguanosine. The solvated electron gives rise to an intermediate which is rapidly protonated by water (pKa > 11). Quantum mechanical calculations support the assignment of the 400 nm (450 nm) absorption to the respective dimeric thiourea radical cation. (author)

  10. Exploring how lead users develop radical innovation

    DEFF Research Database (Denmark)

    Lettl, Christopher; Gemuenden, Hans Georg; Hienerth, C.

    2008-01-01

    In this study, we explore how lead users develop radical innovations outside of manufacturing firms. We analyze the transition from a very early stage of activities to the ultimate commercialization of these innovations. The focus in this context is on the initiatives undertaken by lead users in...... lead users as surgeons launch entrepreneurial activities and bridge periods in which established medical equipment manufacturers would not risk investing in radical innovations. By doing so, lead users create the conditions usually provided in manufacturer-initiated lead user projects, including the...... supply of diversified knowledge, the development and coordination of a network for further development of the innovation, and initial tests of technical or market feasibility. Our findings have implications for manufacturing firms that wish to design radical innovation projects with (individual) lead...

  11. Radiation chemistry of aromatic dimer radical cations

    International Nuclear Information System (INIS)

    π-π Interactions of aromatic molecules are paid attention much in many fields, especially biology, chemistry, and applied physics, represented as protein, DNA, electron donor-accepter complexes, charge transfers, and self assembly molecules. Aromatic molecules including benzene rings are the simplest case to study the π-π interactions. To interpret the charge resonance (CR) structure in the dimer radical cations, spectroscopic and ESR methods have been carried out. The spectroscopic study on the dimer radical ion of molecules with two chromophores would be profitable to identify the electronic and configurational properties. In this article, dynamics of the dimer radical cation of benzenes, polystyrenes, and resist polymers is described on the basis of direct observation of CR band by the nanosecond pulse radiolysis and low temperature γ-radiolysis methods. (author)

  12. Radical abdominoplasty, including body shaping: representative cases.

    Science.gov (United States)

    Mühlbauer, W

    1989-01-01

    Even in the age of liposuction there exist certain situations for which abdominoplasty in its radical form is indicated--for example, redundant skin after radical weight loss, the stigmata of postpregnancy syndrome, and localized accumulation of adipose tissue--the lipodystrophies and resistant generalized obesity. Redundant skin after radical weight loss is resected simultaneously around the abdomen, the lumbar regions, the perineum, and the thighs. The typical stigmata of postpregnancy syndrome may be excised through an extended abdominoplasty combined with simultaneous excision and pexy of the inner aspects of the thighs leaving a "bikini" scar behind. A mastopexy may be added. Genetically predisposed localized lipodystrophies in the abdominal lumbar, and upper thigh region may be resected through a circular abdominoplasty with or without simultaneous resection of the perineum and inner thighs. Abdominal aprons often contain umbilical or ventral hernias that may need to be repaired simultaneously. Representative cases are presented and dangers and complications are discussed. PMID:2741749

  13. Free Radicals in Adolescent Varicocele Testis

    OpenAIRE

    Carmelo Romeo; Giuseppe Santoro

    2014-01-01

    We examine the relationship between the structure and function of the testis and the oxidative and nitrosative stress, determined by an excessive production of free radicals and/or decreased availability of antioxidant defenses, which occur in the testis of adolescents affected by varicocele. Moreover, the effects of surgical treatment on oxidative stress were provided. We conducted a PubMed and Medline search between 1980 and 2014 using “adolescent,” “varicocele,” “free radicals,” “oxidative...

  14. Free-radical kinetics of coal liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Wang, M.; Smith, J.M.; McCoy, B.J.

    1994-07-16

    A rate expression with first- and second-order terms in the concentration of extractable compounds in solid coal particles is derived from a fundamental free-radical mechanism. The expression was suggested empirically by prior experiments for coal liquefaction in the presence of a hydrogen-donor solvent. Radical reactions are considered to occur in both coal and in solvent. The long-chain approximation justifies the neglect of initiation, hydrogen abstraction, and termination rates as quantitatively insignificant relative to propagation reaction rates.

  15. Resonance ionization detection of combustion radicals

    Energy Technology Data Exchange (ETDEWEB)

    Cool, T.A. [Cornell Univ., Ithaca, NY (United States)

    1993-12-01

    Fundamental research on the combustion of halogenated organic compounds with emphasis on reaction pathways leading to the formation of chlorinated aromatic compounds and the development of continuous emission monitoring methods will assist in DOE efforts in the management and disposal of hazardous chemical wastes. Selective laser ionization techniques are used in this laboratory for the measurement of concentration profiles of radical intermediates in the combustion of chlorinated hydrocarbon flames. A new ultrasensitive detection technique, made possible with the advent of tunable VUV laser sources, enables the selective near-threshold photoionization of all radical intermediates in premixed hydrocarbon and chlorinated hydrocarbon flames.

  16. Resonant cavity spectroscopy of radical species

    Science.gov (United States)

    Ritchie, Grant

    2015-04-01

    Photo-oxidation in the troposphere is highly complex, being initiated by short lived radical species, in the daytime dominated by the hydroxyl radical, OH, with contributions from Cl atoms, and at night by either NO3 radicals or ozone. Chemical oxidation cycles, which couple OH, HO2 and peroxy (RO2) radical species, remove primary emitted trace species which are harmful to humans or to the wider environment. However, many of the secondary products produced by atmospheric photo-oxidation are also directly harmful, for example O3, NO2, acidic and multifunctional species, many of which are of low volatility and are able to partition effectively to the condensed phase, creating secondary organic aerosol (SOA), which contributes a significant fraction of tropospheric aerosol, with associated impacts on climate and human health. The accuracy of atmospheric models to predict these impacts necessarily requires accurate knowledge of the chemical oxidative cycling. Two of the simplest intermediates are the hydroperoxy radical, HO2, and the smallest and dominant organic peroxy radical, CH3O2, formed directly by the reactions of OH with CO/O2 and CH4/O2, respectively, and indirectly following the oxidation of larger VOCs. OH, HO2 and RO2 (collectively known as ROx) are rapidly cycled, being at the centre of tropospheric oxidation, and hence are some of the best targets for models to compare with field data. The reaction of HO2 and RO2 with NO constitutes the only tropospheric in-situ source of O3. Despite their importance, neither HO2 nor CH3O2 is measured directly in the atmosphere. HO2 is only measured indirectly following its conversion to OH and CH3O2 is not measured at all. Typically only the sum of RO2 radicals is measured, making no distinction between different organic peroxy radicals. This contribution will detail recent studies using (i) optical feedback cavity enhanced absorption spectroscopy with both quantum and inter-band cascade lasers in the mid-IR, and (ii

  17. Glutathione--hydroxyl radical interaction: a theoretical study on radical recognition process.

    Directory of Open Access Journals (Sweden)

    Béla Fiser

    Full Text Available Non-reactive, comparative (2 × 1.2 μs molecular dynamics simulations were carried out to characterize the interactions between glutathione (GSH, host molecule and hydroxyl radical (OH(•, guest molecule. From this analysis, two distinct steps were identified in the recognition process of hydroxyl radical by glutathione: catching and steering, based on the interactions between the host-guest molecules. Over 78% of all interactions are related to the catching mechanism via complex formation between anionic carboxyl groups and the OH radical, hence both terminal residues of GSH serve as recognition sites. The glycine residue has an additional role in the recognition of OH radical, namely the steering. The flexibility of the Gly residue enables the formation of further interactions of other parts of glutathione (e.g. thiol, α- and β-carbons with the lone electron pair of the hydroxyl radical. Moreover, quantum chemical calculations were carried out on selected GSH/OH(• complexes and on appropriate GSH conformers to describe the energy profile of the recognition process. The relative enthalpy and the free energy changes of the radical recognition of the strongest complexes varied from -42.4 to -27.8 kJ/mol and from -21.3 to 9.8 kJ/mol, respectively. These complexes, containing two or more intermolecular interactions, would be the starting configurations for the hydrogen atom migration to quench the hydroxyl radical via different reaction channels.

  18. Radical scavenging ability of some compounds isolated from Piper cubeba towards free radicals.

    Science.gov (United States)

    Aboul-Enein, Hassan Y; Kładna, Aleksandra; Kruk, Irena

    2011-01-01

    The purpose of this study was to identify the antioxidant activity of 16 compounds isolated from Piper cubeba (CNCs) through the extent of their capacities to scavenge free radicals, hydroxyl radical (HO(•)), superoxide anion radical O•(2)(-) and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH(•)), in different systems. Electron paramagnetic resonance (EPR) and 5,5-dimethyl-1-pyrroline-N-oxide, DMPO, as the spin trap, and chemiluminescence techniques were applied. Using the Fenton-like reaction [Fe(II) + H(2)O(2)], CNCs were found to inhibit DMPO-OH radical formation ranging from 5 to 57% at 1.25 mmol L(-1) concentration. The examined CNCs also showed a high DPPH antiradical activity (ranging from 15 to 99% at 5 mmol L(-1) concentration). Furthermore, the results indicated that seven of the 16 tested compounds may catalyse the conversion of superoxide radicals generated in the potassium superoxide/18-crown-6 ether system, thus showing superoxide dismutase-like activity. The data obtained suggest that radical scavenging properties of CNCs might have potential application in many plant medicines. PMID:21681910

  19. Inactivation efficiencies of radical reactions with biologically active DNA

    International Nuclear Information System (INIS)

    Dilute aqueous solutions of biologically active ΦX174 DNA may serve as a simplified model system of the cell. Damage to the DNA after irradiation with γ-rays, may be ascribed to reactions with radical OH, radical H and esub(aq)- or secondary radicals, arising from reactions of water radicals with added scavengers. Conversion of primary (water) radicals into secondary (scavenger) radicals leads to a considerable protection of the DNA, which however, would have been larger if these secondary radicals did not contribute to DNA inactivation. The inactivation yield due to isopropanol or formate (secondary) radicals depends on dose rate as well as DNA concentration. Furthermore the inactivation efficiencies of the reactions of both the primary and the secondary radicals with single-stranded DNA could be established. (author)

  20. Estimation of Crystallinity and Crystallite Size of Cellulose in Benzylated Fibres of Oil Palm Empty Fruit Bunches by X-Ray Diffraction

    Science.gov (United States)

    Deraman, Mohamad; Zakaria, Sarani; Murshidi, Julie Andrianny

    2001-05-01

    Benzylated fibre (BzF) was produced from fibres of oil palm empty fruit bunches (EFBs) using benzyl chloride in an etherification reaction for 2 h at two reaction temperatures, 100°C and 110°C. Estimates based on X-ray diffraction data show decreases of approximately 15 and 17%, respectively, in the crystallinity of cellulose, and 36 and 54% in the size of crystallites cellulose in the BzF(100°C) and BzF(110°C) samples. This indicates a greater effect on crystallite size than on crystallinity because the conversion of some crystalline cellulose in the crystallite domain into an amorphous state is accompanied by the breakage of the crystallite domain into smaller sizes. Furthermore, the results also indicate that the increase of reaction temperature from 100°C to 110°C results in a larger change in crystallite size than in crystallinity.

  1. Development of 3-methoxy-4-benzyloxybenzyl alcohol (MBBA) resin as polymer-supported synthesis support: Preparation and benzyl ether cleavage by DDQ oxidation

    Indian Academy of Sciences (India)

    Qiang Huang; Bao-Zhong Zheng; Quan Long

    2010-03-01

    3-Methoxy-4-benzyloxybenzyl alcohol (MBBA) resin was synthesized by a two-step sequence under microwave irradiation involving the reaction of commercially available Merrifield resin with vanillin, followed by reduction with sodium borohydride. MBBA resin was treated with bromides in the presence of sodium hydride to afford the corresponding resin-bound benzyl ethers. Cleavage of the resin-bound benzyl ethers from the MBBA resin was carried out using 2,3-dichloro-5,6-dicyanobenzoqunone (DDQ) to give the corresponding alcohols in good yields. Moreover, the recovery, regeneration, and reuse of this polymer support could be achieved easily. MBBA resin can be developed as a kind of solid-phase synthesis bead of alcohols.

  2. Oxidation of o-chloro and o-hydroxy benzyl alcohols catalyzed by copper (II tetraphenylporphyrin nanoparticles synthesized by mixed solvent method

    Directory of Open Access Journals (Sweden)

    Rahmatollah Rahimi

    2012-07-01

    Full Text Available Tetraphenylporphyrin (TPP and copper tetraphenylporphyrin (CuTPP were synthesized and characterized by IR, UV-Vis, 1HNMR and 13CNMR. The CuTPP nanoparticles were synthesized by sonication and mixed solvent methods. These nanoparticles were characterized by AFM and SEM images and UV-Vis spectra. The catalytic activity of nanoparticles was investigated by oxidation of o-choloro and o-hydroxy benzyl alcohols in presence of molecular oxygen and isobutyraldehyde. The yields of oxidation of o-hydroxy benzyl alcohol by the two catalysts, CuTPP NPs and CuTPP, are 96.5% and ~ 2%, respectively. It is very obvious that the oxidation at the presence of CuTPP NPs catalyst is very high but selectivity for both reactants is 100%.‎

  3. Extraction and Chromatographic Determination of Shikimic Acid in Chinese Conifer Needles with 1-Benzyl-3-methylimidazolium Bromide Ionic Liquid Aqueous Solutions

    OpenAIRE

    2014-01-01

    An ionic liquids-based ultrasound-assisted extraction (ILUAE) method was successfully developed for extracting shikimic acid from conifer needles. Eleven 1-alkyl-3-methylimidazolium ionic liquids with different cations and anions were investigated and 1-benzyl-3-methylimidazolium bromide solution was selected as the solvent. The conditions for ILUAE, including the ionic liquid concentration, ultrasound power, ultrasound time, and liquid-solid ratio, were optimized. The proposed method had goo...

  4. Skin oxygenation after topical application of liposome-entrapped benzyl nicotinate as measured by EPR oximetry in vivo: Influence of composition and size

    OpenAIRE

    Kristl, Julijana; Abramovié, Zrinka; Šentjure, Marjeta

    2003-01-01

    New and improved drug delivery systems are the important subject of much scientific research. The development of formulations that increase skin oxygenation and of methods for measuring oxygen levels in skin are important for dealing with healing processes affected by the level of oxygen. We have use EPR oximetry in vivo to compare the influence of liposomal formulations of different size and composition with that of hydrogel with respect to the action of the entrapped benzyl nicotinate (BN)....

  5. Transition metal-free oxidation of benzylic alcohols to carbonyl compounds by hydrogen peroxide in the presence of acidic silica gel

    Directory of Open Access Journals (Sweden)

    Hossein Ghafuri

    2015-01-01

    Full Text Available Oxidation of alcohols to carbonyl compounds has become an important issue in the process industry as well as many other applications. In this method, various benzylic alcohols were successfully converted to corresponding aldehydes and ketones under transition metal-free condition using hydrogen peroxide in the presence of some amount of catalytic acidic silica gel. Silica gel is inexpensive and available. One of the most important features of this method is its short reaction time.

  6. Oxidation of o-chloro and o-hydroxy benzyl alcohols catalyzed by copper (II) tetraphenylporphyrin nanoparticles synthesized by mixed solvent method

    OpenAIRE

    Rahmatollah Rahimi; Ensieh Gholamrezapor; Mohammad Reza Naimi-Jamal; Mahboubeh Rabbani

    2012-01-01

    Tetraphenylporphyrin (TPP) and copper tetraphenylporphyrin (CuTPP) were synthesized and characterized by IR, UV-Vis, 1HNMR and 13CNMR. The CuTPP nanoparticles were synthesized by sonication and mixed solvent methods. These nanoparticles were characterized by AFM and SEM images and UV-Vis spectra. The catalytic activity of nanoparticles was investigated by oxidation of o-choloro and o-hydroxy benzyl alcohols in presence of molecular oxygen and isobutyraldehyde. The yields of oxidation of o-hyd...

  7. Electrospinning of poly(.gamma.-benzyl-L-glutamate) nanofibres: the effect of polymer molecular weight and spinning conditions in various solvents

    Czech Academy of Sciences Publication Activity Database

    Svobodová, Jana; Rypáček, František

    Granada: European Polymer Federation, 2011. s. 1179. ISBN 978-84-694-3124-5. [European Polymer Congress 2011, Congress of the Specialized Group of Polymers /12./. 26.06.2011-01.07.2011, Granada] R&D Projects: GA AV ČR KJB400500904; GA MŠk 1M0538 Institutional research plan: CEZ:AV0Z40500505 Keywords : poly(.gamma.-benzyl-L-glutamate) * electrospinning Subject RIV: CD - Macromolecular Chemistry

  8. 1-Benzyl-2-methyl-3-indolylmethylene barbituric acid derivatives: Anti-cancer agents that target nucleophosmin 1 (NPM1).

    Science.gov (United States)

    Penthala, Narsimha Reddy; Ketkar, Amit; Sekhar, Konjeti R; Freeman, Michael L; Eoff, Robert L; Balusu, Ramesh; Crooks, Peter A

    2015-11-15

    In the present study, we have designed and synthesized a series of 1-benzyl-2-methyl-3-indolylmethylene barbituric acid analogs (7a-7h) and 1-benzyl-2-methyl-3-indolylmethylene thiobarbituric acid analogs (7 i-7 l) as nucleophosmin 1 (NPM1) inhibitors and have evaluated them for their anti-cancer activity against a panel of 60 different human cancer cell lines. Among these analogs 7 i, 7 j, and 7 k demonstrated potent growth inhibitory effects in various cancer cell types with GI50 values <2 μM. Compound 7 k exhibited growth inhibitory effects on a sub-panel of six leukemia cell lines with GI50 values in the range 0.22-0.35 μM. Analog 7 i also exhibited GI50 values <0.35 μM against three of the leukemia cell lines in the sub-panel. Analogs 7 i, 7 j, 7 k and 7 l were also evaluated against the mutant NPM1 expressing OCI-AML3 cell line and compounds 7 k and 7 l were found to cause dose-dependent apoptosis (AP50 = 1.75 μM and 3.3 μM, respectively). Compound 7k also exhibited potent growth inhibition against a wide variety of solid tumor cell lines: that is, A498 renal cancer (GI50 = 0.19 μM), HOP-92 and NCI-H522 lung cancer (GI50 = 0.25 μM), COLO 205 and HCT-116 colon cancer (GI50 = 0.20 and 0.26 μM, respectively), CNS cancer SF-539 (GI50 = 0.22 μM), melanoma MDA-MB-435 (GI50 = 0.22 μM), and breast cancer HS 578T (GI50 = 0.22 μM) cell lines. Molecular docking studies suggest that compounds 7 k and 7 l exert their anti-leukemic activity by binding to a pocket in the central channel of the NPM1 pentameric structure. These results indicate that the small molecule inhibitors 7 i, 7 j, 7 k, and 7 l could be potentially developed into anti-NPM1 drugs for the treatment of a variety of hematologic malignancies and solid tumors. PMID:26602084

  9. Radical recombinations in acetylene-air flames

    NARCIS (Netherlands)

    Zeegers, P.J.Th.; Alkemade, C.T.J.

    1965-01-01

    In this paper an analysis is given of the behaviour of excess radical concentrations, H, OH and O as a function of height above the reaction zone in premixed acetylene-air flames at 2–200° to 2400°K and 1 atmosphere pressure. The intensity was measured of the Li resonance line which is related to th

  10. Free-radical inactivation of muscle aldolase

    International Nuclear Information System (INIS)

    Rabbit muscle aldolase has been shown to be deactivated by addition of irradiated crystals of various sugars and amino acids. Inactivation observed immediately upon dissolution is ascribed to reaction with free radicals, whereas post-dissolution inactivation is ascribed to acid-catalyzed reaction with nonradical radiolysis products. (U.S.)

  11. Lipophilic fluorescent products of free radicals

    Czech Academy of Sciences Publication Activity Database

    Ivica, Josko; Wilhelm, Jiří

    2014-01-01

    Roč. 158, č. 3 (2014), s. 365-372. ISSN 1213-8118 R&D Projects: GA ČR(CZ) GAP303/11/0298 Institutional support: RVO:67985823 Keywords : lipofuscin-like pigments * lipid peroxidation * free radicals * fluorescence Subject RIV: CE - Biochemistry Impact factor: 1.200, year: 2014

  12. Discourses of postmodern epistemology: Radical impetus lost?

    OpenAIRE

    Mueller, Martin

    2006-01-01

    Exhibiting a highly divisive agenda postmodernism has created profound chasms across scientific communities. In development studies its radical impetus has translated into the postdevelopment perspective which violently repudiates the modernist development project. This paper crystallises two distinct discourses of working upon the epistemological raw material of postmodernism: an exclusivist discourse, which reinforces the chasm by isolating postmodernism, and an inclusivist discourse, which...

  13. Identity and Islamic Radicalization in Western Europe

    NARCIS (Netherlands)

    S.M. Murshed (Syed); S. Pavan (Sara)

    2009-01-01

    textabstractThis paper argues that both socio-economic disadvantage and political factors, such as the West’s foreign policy with regard to the Muslim world, along with historical grievances, play a part in the development of Islamic radicalized collective action in Western Europe. We emphasise the

  14. Designed metalloprotein stabilizes a semiquinone radical.

    Science.gov (United States)

    Ulas, Gözde; Lemmin, Thomas; Wu, Yibing; Gassner, George T; DeGrado, William F

    2016-04-01

    Enzymes use binding energy to stabilize their substrates in high-energy states that are otherwise inaccessible at ambient temperature. Here we show that a de novo designed Zn(II) metalloprotein stabilizes a chemically reactive organic radical that is otherwise unstable in aqueous media. The protein binds tightly to and stabilizes the radical semiquinone form of 3,5-di-tert-butylcatechol. Solution NMR spectroscopy in conjunction with molecular dynamics simulations show that the substrate binds in the active site pocket where it is stabilized by metal-ligand interactions as well as by burial of its hydrophobic groups. Spectrochemical redox titrations show that the protein stabilized the semiquinone by reducing the electrochemical midpoint potential for its formation via the one-electron oxidation of the catechol by approximately 400 mV (9 kcal mol(-1)). Therefore, the inherent chemical properties of the radical were changed drastically by harnessing its binding energy to the metalloprotein. This model sets the basis for designed enzymes with radical cofactors to tackle challenging chemistry. PMID:27001731

  15. Radical Chemistry in the Gas Phase

    Czech Academy of Sciences Publication Activity Database

    Alcaraz, Ch.; Fischer, I.; Schröder, Detlef

    New York: John Wiley and Sons, 2012 - (Chatgilialoglu, C.; Studer, A.), s. 477-502 ISBN 978-0-470-97125-3 Grant ostatní: European Research Council(XE) AdG HORIZOMS Institutional research plan: CEZ:AV0Z40550506 Keywords : radicals * reactive intermediates * gas phase * photoionization * unimolecular reactions * bimolecular reactions Subject RIV: CF - Physical ; Theoretical Chemistry

  16. Radical Islamism and Migrant Integration in Denmark

    DEFF Research Database (Denmark)

    Goli, Marco; Rezaei, Shahamak

    2011-01-01

    for – or consequence of - their societal integration. Conventional wisdom suggests: “The more you associate yourself with the cherished and established goals and means, the more you will disassociate yourself from Radical Islamism”, and vice versa. We believe that, quite surprisingly, an empirical test of this idea...

  17. Designed metalloprotein stabilizes a semiquinone radical

    Science.gov (United States)

    Ulas, Gözde; Lemmin, Thomas; Wu, Yibing; Gassner, George T.; Degrado, William F.

    2016-04-01

    Enzymes use binding energy to stabilize their substrates in high-energy states that are otherwise inaccessible at ambient temperature. Here we show that a de novo designed Zn(II) metalloprotein stabilizes a chemically reactive organic radical that is otherwise unstable in aqueous media. The protein binds tightly to and stabilizes the radical semiquinone form of 3,5-di-tert-butylcatechol. Solution NMR spectroscopy in conjunction with molecular dynamics simulations show that the substrate binds in the active site pocket where it is stabilized by metal-ligand interactions as well as by burial of its hydrophobic groups. Spectrochemical redox titrations show that the protein stabilized the semiquinone by reducing the electrochemical midpoint potential for its formation via the one-electron oxidation of the catechol by approximately 400 mV (9 kcal mol-1). Therefore, the inherent chemical properties of the radical were changed drastically by harnessing its binding energy to the metalloprotein. This model sets the basis for designed enzymes with radical cofactors to tackle challenging chemistry.

  18. Neglected Side Effects After Radical Prostatectomy

    DEFF Research Database (Denmark)

    Frey, Anders Ullmann; Sønksen, Jens; Fode, Mikkel

    2014-01-01

    INTRODUCTION: A series of previously neglected sexually related side effects to radical prostatectomy (RP) has been identified over the recent years. These include orgasm-associated incontinence (OAI), urinary incontinence in relation to sexual stimulation (UISS), altered perception of orgasm, or...

  19. Ultraviolet photodissociation dynamics of the phenyl radical

    International Nuclear Information System (INIS)

    Ultraviolet (UV) photodissociation dynamics of jet-cooled phenyl radicals (C6H5 and C6D5) are studied in the photolysis wavelength region of 215-268 nm using high-n Rydberg atom time-of-flight and resonance enhanced multiphoton ionization techniques. The phenyl radicals are produced from 193-nm photolysis of chlorobenzene and bromobenzene precursors. The H-atom photofragment yield spectra have a broad peak centered around 235 nm and are in good agreement with the UV absorption spectra of phenyl. The H + C6H4 product translational energy distributions, P(ET)'s, peak near ∼7 kcal/mol, and the fraction of average translational energy in the total excess energy, T>, is in the range of 0.20-0.35 from 215 to 268 nm. The H-atom product angular distribution is isotropic. The dissociation rates are in the range of 107-108 s-1 with internal energy from 30 to 46 kcal/mol above the threshold of the lowest energy channel H +o-C6H4 (ortho-benzyne), comparable with the rates from the Rice-Ramsperger-Kassel-Marcus theory. The results from the fully deuterated phenyl radical are identical. The dissociation mechanism is consistent with production of H +o-C6H4, as the main channel from unimolecular decomposition of the ground electronic state phenyl radical following internal conversion of the electronically excited state.

  20. DNP with Trityl Radicals in Deuterated Polyethylene

    Science.gov (United States)

    Wang, Li; Meyer, W.; Berlin, A.; Herick, J.; Hess, C.; Reicherz, G.

    2016-02-01

    Chemically doping with trityl radicals was performed in fully deuterated polyethylene. The behavior of paramagnetic centers has been investigated by ESR X-band spectrometer. The highest deuteron polarization was 8% at 2.5 T and 1 K with a spin concentration of 3 × 1019 spins/g.

  1. Reactions of the CN Radical with Benzene and Toluene: Product Detection and Low-Temperature Kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Trevitt, Adam J.; Goulay, Fabien; Taatjes, Craig A.; Osborn, David L.; Leone, Stephen R.

    2009-12-23

    Low temperature rate coefficients are measured for the CN + benzene and CN + toluene reactions using the pulsed Laval nozzle expansion technique coupled with laser-induced fluorescence detection. The CN + benzene reaction rate coefficient at 105, 165 and 295 K is found to be relatively constant over this temperature range, 3.9 - 4.9 x 10-10 cm3 molecule-1 s-1. These rapid kinetics, along with the observed negligible temperature dependence, are consistent with a barrierless reaction entrance channel and reaction efficiencies approaching unity. The CN + toluene reaction is measured to have a slower rate coefficient of 1.3 x 10-10 cm3 molecule-1 s-1 at 105 K. At room temperature, non-exponential decay profiles are observed for this reaction that may suggest significant back-dissociation of intermediate complexes. In separate experiments, the products of these reactions are probed at room temperature using synchrotron VUV photoionization mass spectrometry. For CN + benzene, cyanobenzene (C6H5CN) is the only product recorded with no detectable evidence for a C6H5 + HCN product channel. In the case of CN + toluene, cyanotoluene (NCC6H4CH3) constitutes the only detected product. It is not possible to differentiate among the ortho, meta and para isomers of cyanotoluene because of their similar ionization energies and the ~;; 40 meV photon energy resolution of the experiment. There is no significant detection of benzyl radicals (C6H5CH2) that would suggest a H-abstraction or a HCN elimination channel is prominent at these conditions. As both reactions are measured to be rapid at 105 K, appearing to have barrierless entrance channels, it follows that they will proceed efficiently at the temperatures of Saturn?s moon Titan (~;;100 K) and are also likely to proceed at the temperature of interstellar clouds (10-20 K).

  2. Crystal structure of N′′-benzyl-N′′-[3-(benzyl­dimethyl­aza­nium­yl)prop­yl]-N,N,N′,N′-tetra­methyl­guanidinium bis­(tetra­phenyl­borate)

    Science.gov (United States)

    Tiritiris, Ioannis; Kantlehner, Willi

    2015-01-01

    In the crystal structure of the title salt, C24H38N4 2+·2C24H20B−, the C—N bond lengths in the central CN3 unit of the guanidinium ion are 1.3364 (13), 1.3407 (13) and 1.3539 (13) Å, indicating partial double-bond character. The central C atom is bonded to the three N atoms in a nearly ideal trigonal–planar geometry and the positive charge is delocalized in the CN3 plane. The bonds between the N atoms and the terminal methyl groups of the guanidinium moiety and the four C—N bonds to the central N atom of the (benzyl­dimethyl­aza­nium­yl)propyl group have single-bond character. In the crystal, C—H⋯π inter­actions between the guanidin­ium H atoms and the phenyl C atoms of the tetra­phenyl­borate ions are present, leading to the formation of a two-dimensional supra­molecular pattern parallel to the ac plane. PMID:26870511

  3. Hydroxyl Radical Dosimetry for High Flux Hydroxyl Radical Protein Footprinting Applications Using a Simple Optical Detection Method.

    Science.gov (United States)

    Xie, Boer; Sharp, Joshua S

    2015-11-01

    Hydroxyl radical protein footprinting (HRPF) by fast photochemical oxidation of proteins (FPOP) is a powerful benchtop tool used to probe protein structure, interactions, and conformational changes in solution. However, the reproducibility of all HRPF techniques is limited by the ability to deliver a defined concentration of hydroxyl radicals to the protein. This ability is impacted by both the amount of radical generated and the presence of radical scavengers in solution. In order to compare HRPF data from sample to sample, a hydroxyl radical dosimeter is needed that can measure the effective concentration of radical that is delivered to the protein, after accounting for both differences in hydroxyl radical generation and nonanalyte radical consumption. Here, we test three radical dosimeters (Alexa Fluor 488, terepthalic acid, and adenine) for their ability to quantitatively measure the effective radical dose under the high radical concentration conditions of FPOP. Adenine has a quantitative relationship between UV spectrophotometric response, effective hydroxyl radical dose delivered, and peptide and protein oxidation levels over the range of radical concentrations typically encountered in FPOP. The simplicity of an adenine-based dosimeter allows for convenient and flexible incorporation into FPOP applications, and the ability to accurately measure the delivered radical dose will enable reproducible and reliable FPOP across a variety of platforms and applications. PMID:26455423

  4. Selective oxidation of benzyl alcohol with tert-butylhydroperoxide catalysed via Mn (II) 2, 2-bipyridine complexes immobilized over the mesoporous hexagonal molecular sieves (HMS)

    Indian Academy of Sciences (India)

    Vahid Mahdavi; Mahdieh Mardani

    2012-09-01

    A series ofMn(II)bipy complexes with different loading of Mn2+ supported on HMS was prepared. These samples were characterized by Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), Thermogravimetric and Differential Scanning Calorimetry (TG-DSC), Ultraviolet and Visible spectra (UV-Vis) and Fourier transforms Infrared (FT-IR). The catalytic activity of the supportedMn(II)bipy complexes, [Mn(bipy)2]2+/HMS was evaluated in the oxidation of benzyl alcohol in the liquid phase using tert-butylhydroperoxide (TBHP) as an oxidant. The effects of Mn2+ loading and various solvents on the conversion and selectivity were studied. A second order function for the variation in catalytic activity with respect to the loading of Mn2+ ions in different catalyst samples was observed. The activity of the [Mn(bipy)2]2+/HMS catalyst differs with the type of the solvent and in this case, acetonitrile gives the best conversion results. The kinetic of benzyl alcohol oxidation was investigated at temperatures of 27, 46, 60, 75 and 90°C using [Mn(bipy)2]2+/HMS and excess TBHP. The order of reaction with respect to benzyl alcohol was determined to be pseudo-first order. The value of the apparent activation energy was also determined.

  5. SYNTHESIS AND CHARACTERIZATION OF POLY(AMINO ACID-UREA)S COMPRISING NOVEL TRIBLOCK COPOLYMERS OF POLY(TETRAHYDROFURAN) AND POLY(γ-BENZYL L-GLUTAMATE)S

    Institute of Scientific and Technical Information of China (English)

    Hai-bin Li; Zhen Tian; Ai-ying Zhang; Zeng-guo Feng

    2009-01-01

    A kind of novel triblock copolymers of poly(y:benzyl L-glutamate)-b-poly(tetrahydrofuran)-b-poly(γ-benzyl L-glutamate)s (PBLG-b-PTHF-b-PBLG) was synthesized by using bis(3-aminopropyl) terminated polytetrahydrofuran to initiate the ring-opening polymerization of γ-benzyl L-glutamate N-carboxyanhydride (BLG-NCA). The corresponding multiblock poly(amino aeid-urea)s were prepared in one-pot protocol from the chain extension of PBLG-b-PTHF-b-PBLG with MDI. The resulting triblock and multiblock copolymers were characterized by FFIR, 1H-NMR, 13C-NMR and GPC techniques. It is demonstrated that the chain extension has taken place to give rise to the copolymers with the well-defined block composition and narrow molecular weight distribution. A distinct Tg arising from the hard-segments was observed in all the copolymers. Their mechanical properties showed an increasing trend with the molecular weight enhancement of the prepolymers.

  6. Plasmonic Au/CdMoO{sub 4} photocatalyst: Influence of surface plasmon resonance for selective photocatalytic oxidation of benzylic alcohol

    Energy Technology Data Exchange (ETDEWEB)

    Bi, Jinhong, E-mail: bijinhong@fzu.edu.cn [Department of Environmental Science and Engineering, Fuzhou University, Minhou, Fujian 350108 (China); Research Institute of Photocatalysis, State Key Laboratory Photocatalysis on Energy and Environment, Fuzhou University, Fuzhou, Fujian 350002 (China); Zhou, Zhiyong; Chen, Mengying [Department of Environmental Science and Engineering, Fuzhou University, Minhou, Fujian 350108 (China); Liang, Shijing [Department of Environmental Science and Engineering, Fuzhou University, Minhou, Fujian 350108 (China); Research Institute of Photocatalysis, State Key Laboratory Photocatalysis on Energy and Environment, Fuzhou University, Fuzhou, Fujian 350002 (China); He, Yunhui; Zhang, Zizhong [Research Institute of Photocatalysis, State Key Laboratory Photocatalysis on Energy and Environment, Fuzhou University, Fuzhou, Fujian 350002 (China); Wu, Ling, E-mail: wuling@fzu.edu.cn [Research Institute of Photocatalysis, State Key Laboratory Photocatalysis on Energy and Environment, Fuzhou University, Fuzhou, Fujian 350002 (China)

    2015-09-15

    Graphical abstract: - Highlights: • Au/CdMoO{sub 4} composites were constructed for the first time. • Au/CdMoO{sub 4} showed superior activity for selective oxidation of benzylic alcohol. • The visible light photocatalytic activity is ascribed to the SPR effect of Au. - Abstract: Novel visible-light-driven plasmonic Au/CdMoO{sub 4} photocatalysts were synthesized by hydrothermal process following chemical reduction process. The catalysts were characterized by X-ray diffraction, transmission electron microscopy, UV–vis diffuse reflectance spectroscopy and X-ray photoelectron spectroscopy. The results show the catalysts exhibited strong visible light absorption due to the surface plasmon resonance effect of Au nanoparticles. Compared to CdMoO{sub 4}, Au/CdMoO{sub 4} composites displayed superior photocatalytic activities for the selective oxidation of benzylic alcohol to benzaldehyde under visible light. The highest conversion was obtain by the 1.6% Au loaded CdMoO{sub 4}. The mechanism for the selective oxidation of benzylic alcohol in the Au/CdMoO{sub 4} system is proposed.

  7. Synthesis and in vitro pharmacological evaluation of N-[(1-benzyl-1,2,3-triazol-4-yl)methyl]-carboxamides on d-secoestrone scaffolds.

    Science.gov (United States)

    Szabó, Johanna; Bacsa, Ildikó; Wölfling, János; Schneider, Gyula; Zupkó, István; Varga, Mónika; Herman, Bianka E; Kalmár, László; Szécsi, Mihály; Mernyák, Erzsébet

    2016-08-01

    An efficient synthesis of several N-[(1-benzyl-1,2,3-triazol-4-yl)methyl]carboxamides in the 13β- and 13α-d-secoestrone series is reported. Novel triazoles were synthesized via the Cu(I)-catalyzed azide-alkyne cycloaddition of steroidal alkynyl carboxamides and p-substituted benzyl azides. Each of the products was evaluated in vitro by means of MTT assays for antiproliferative activity against a panel of human adherent cancer cell lines (HeLa, MCF-7, A431 and A2780). Some of them exhibited activities similar to those of the reference agent cisplatin. On change of the substitution pattern of the benzyl group of the azide, great differences in the cell growth-inhibitory properties were observed. The p-alkylbenzyl-substituted triazoles selectively exerted high cytostatic action against A2780 cells, with IC50 values of 1 µM. We investigated the potential inhibitory action exerted on the human 17β-HSD1 activity of the new secosteroids. Three triazoles effectively suppressed the estrone to 17β-estradiol conversion with IC50 values in low micromolar range. PMID:26360618

  8. The Benzyl Ester Group of Amino Acid Monomers Enhances Substrate Affinity and Broadens the Substrate Specificity of the Enzyme Catalyst in Chemoenzymatic Copolymerization.

    Science.gov (United States)

    Ageitos, Jose Manuel; Yazawa, Kenjiro; Tateishi, Ayaka; Tsuchiya, Kousuke; Numata, Keiji

    2016-01-11

    The chemoenzymatic polymerization of amino acid monomers by proteases involves a two-step reaction: the formation of a covalent acyl-intermediate complex between the protease and the carboxyl ester group of the monomer and the subsequent deacylation of the complex by aminolysis to form a peptide bond. Although the initiation with the ester group of the monomer is an important step, the influence of the ester group on the polymerization has not been studied in detail. Herein, we studied the effect of the ester groups (methyl, ethyl, benzyl, and tert-butyl esters) of alanine and glycine on the synthesis of peptides using papain as the catalyst. Alanine and glycine were selected as monomers because of their substantially different affinities toward papain. The efficiency of the polymerization of alanine and glycine benzyl esters was much greater than that of the other esters. The benzyl ester group therefore allowed papain to equally polymerize alanine and glycine, even though the affinity of alanine toward papain is substantially higher. The characterization of the copolymers of alanine and glycine in terms of the secondary structure and thermal properties revealed that the thermal stability of the peptides depends on the amino acid composition and resultant secondary structure. The current results indicate that the nature of the ester group drastically affects the polymerization efficiency and broadens the substrate specificity of the protease. PMID:26620763

  9. Synthesis and characterization of novel triblock copolymers comprising poly(tetrahydrofuran) as a central block and poly(γ-benzyl L-glutamate)s as outer blocks

    Institute of Scientific and Technical Information of China (English)

    Hai-bin LI; Zhen TIAN; Meng WANG; Ai-ying ZHANG; Zeng-guo FENG

    2008-01-01

    BACKGROUND: Bioactive and biodegrad-able polyurethanes (BDPUs) have drawn much attention in recent years. As part of the research program to search for novel prepolymers for BDPUs, a study was carried out on the synthesis and characterization of triblock copoly-mers comprising poly(tetrahydrofuran) as a central block and poly(γ-benzyl L-glutamate)s as outer blocks. RESULTS: A new macroinitiator terminated with pheny-lalanine was first prepared from the condensation of a distal hydroxy poly(tetrahydrofuran) with N-tert-butox-ycarbonyl L-phenylalanine in the presence of dicyclohex-ylcarbodiimide, followed by removing the protecting group. Then, it was employed to initiate the ring-opening polymerization of γ-benzyl L-glutamate N-carboxyanhy-dride in varying feeding ratios to give rise to the targeted triblock copolymers. CONCLUSIONS: The length of the outer poly(γ-benzyl L-glutamate) blocks was well tailored by varying the monomers to macroinitiator feeding ratio. All the triblock copolymers exhibited a nearly symmet-rical and unimodal molecular weight distribution while only one distinct glass transition temperature was evi-denced from -10℃ to 25℃.

  10. A comparative study of silver-graphene oxide nanocomposites as a recyclable catalyst for the aerobic oxidation of benzyl alcohol: Support effect

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • Characteristics of three different graphene oxide (GO) are studied as a support for Ag nanoparticles. • The required conditions for a best support are determined. • For the first time the silver nanoparticles decorated GO as catalyst for aerobic oxidation of benzyl alcohol and the effects of the degree of reduction of GO on AgNPs on GO are reported. - Abstract: Three different nanocomposites of silver and graphene oxide, namely silver nanoparticles (AgNPs) immobilized on reduced graphene oxide (AgNPs/rGO), partially reduced graphene oxide (AgNPs/GO) and thiolated partially reduced graphene oxide (AgNPs/GOSH), were synthesized in order to compare their properties. Characterizations were carried out by infrared and UV–Vis and Raman spectroscopy, ICP, X-ray diffraction, SEM and TEM, confirming both the targeted chemical modification and the composite formation. The nanocomposites were successfully employed in the aerobic oxidation of benzyl alcohol at atmospheric pressure. AgNPs/GOSH is stable and recyclable catalyst which showed the highest activity in the aerobic oxidation of benzyl alcohol in the presence of N-hydroxyphthalimide (NHPI) to give benzaldehyde with 58% selectivity in 24 h at 61% conversion. The favorite properties of AgNPs/GOSH are reasonably attributed to the stable and well distributed AgNPs over GOSH due to strong adhesion between AgNPs and GOSH

  11. Free Radicals in Superfluid Liquid Helium Nanodroplets: A Pyrolysis Source for the Production of Propargyl Radical

    CERN Document Server

    Küpper, J; Miller, R E; K\\"upper, Jochen; Merritt, Jeremy M.; Miller, Roger E.

    2002-01-01

    An effusive pyrolysis source is described for generating a continuous beam of radicals under conditions appropriate for the helium droplet pick-up method. Rotationally resolved spectra are reported for the $\

  12. THE RADICAL ONLINE: INDIVIDUAL RADICALIZATION PROCESSES AND THE ROLE OF THE INTERNET

    Directory of Open Access Journals (Sweden)

    Daniel Koehler

    2014-12-01

    Full Text Available This paper examines in detail the role of the Internet in individual radicalization processes of eight German former right-wing extremists. Applying Grounded Theory methodology the qualitative interviews were analyzed in several coding and re-coding phases. The findings are integrated into the existing literature afterwards. Besides well known factors, such as more effective communication, anonymity and better networking opportunities, this study found evidence that the Internet is a major driving factor to establish and foster the development of radical contrast societies (cf. Koehler, 2015 transmitting radical and violent ideologies and translating them into political activism. As a venue for information exchange, ideological development and training, the individual radicalization process was characteristically shaped or even made possible through the Internet. This paper also shows the high value of qualitative research regarding the topic in contrast to usually employed quantitative analysis of webpage content.

  13. Classical radical hysterectomy and nerve-sparing radical hysterectomy in the treatment of cervical cancer

    OpenAIRE

    Marcin Makowski; Marek Nowak; Marian Szpakowski; Jacek Władziński; Anna Serwach-Nowińska; Łukasz Janas; Jacek R. Wilczyński

    2014-01-01

    Aim of the study: To compare Piver III radical hysterectomy (RH) with nerve-sparing radical hysterectomy (NSRH) for cervical cancer patients in terms of postoperative physiology of pelvic autonomic nerves and perioperative complications. Material and methods : Seventy-three consecutive patients with invasive cervical cancer underwent RH (53 cases) or NSRH (20 cases) from 2001 to 2012 at the Department of Gynecology and Gynecologic Oncology of Polish Mother’s Memorial Hospital – Research...

  14. Spectroscopy of free radicals and radical containing entrance-channel complexes in superfluid helium nanodroplets

    OpenAIRE

    Küpper, J.; Merritt, J.

    2007-01-01

    The spectroscopy of free radicals and radical containing entrance-channel complexes embedded in superfluid helium nano-droplets is reviewed. The collection of dopants inside individual droplets in the beam represents a micro-canonical ensemble, and as such each droplet may be considered an isolated cryo-reactor. The unique properties of the droplets, namely their low temperature (0.4 K) and fast cooling rates ( ~ 1016 K s-1)provides novel opportunities for the formation and high-resolution st...

  15. Environmentally Persistent Free Radicals (EPFRs) - 2. Are Free Hydroxyl Radicals Generated in Aqueous Solutions?

    OpenAIRE

    Khachatryan, Lavrent; Dellinger, Barry

    2011-01-01

    A chemical spin trap, 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), in conjunction with electron paramagnetic resonance (EPR) spectroscopy was employed to measure the production of hydroxyl radical (.OH) in aqueous suspensions of 5% Cu(II)O/silica (3.9% Cu) particles containing environmentally persistent free radicals (EPFRs) of 2-monochlorophenol (2-MCP). The results indicate: 1) a significant differences in accumulated DMPO-OH adducts between EPFR containing particles and non-EPFR control sample...

  16. The plasticizer butyl benzyl phthalate induces genomic changes in rat mammary gland after neonatal/prepubertal exposure

    Directory of Open Access Journals (Sweden)

    Lamartiniere Coral A

    2007-12-01

    Full Text Available Abstract Background Phthalate esters like n-butyl benzyl phthalate (BBP are widely used plasticizers. BBP has shown endocrine-disrupting properties, thus having a potential effect on hormone-sensitive tissues. The aim of this study is to determine the effect of neonatal/prepubertal exposure (post-natal days 2–20 to BBP on maturation parameters and on the morphology, proliferative index and genomic signature of the rat mammary gland at different ages of development (21, 35, 50 and 100 days. Results Here we show that exposure to BBP increased the uterine weight/body weight ratio at 21 days and decreased the body weight at time of vaginal opening. BBP did not induce significant changes on the morphology of the mammary gland, but increased proliferative index in terminal end buds at 35 days and in lobules 1 at several ages. Moreover, BBP had an effect on the genomic profile of the mammary gland mainly at the end of the exposure (21 days, becoming less prominent thereafter. By this age a significant number of genes related to proliferation and differentiation, communication and signal transduction were up-regulated in the glands of the exposed animals. Conclusion These results suggest that BBP has an effect in the gene expression profile of the mammary gland.

  17. Benzyl butyl phthalate promotes adipogenesis in 3T3-L1 preadipocytes: A High Content Cellomics and metabolomic analysis.

    Science.gov (United States)

    Yin, Lei; Yu, Kevin Shengyang; Lu, Kun; Yu, Xiaozhong

    2016-04-01

    Benzyl butyl phthalate (BBP) has been known to induce developmental and reproductive toxicity. However, its association with dysregulation of adipogenesis has been poorly investigated. The present study aimed to examine the effect of BBP on the adipogenesis, and to elucidate the underlying mechanisms using the 3T3-L1 cells. The capacity of BBP to promote adipogenesis was evaluated by multiple staining approaches combined with a High Content Cellomics analysis. The dynamic changes of adipogenic regulatory genes and proteins were examined, and the metabolite profile was identified using GC/MC based metabolomic analysis. The High Content analysis showed BBP in contrast with Bisphenol A (BPA), a known environmental obesogen, increased lipid droplet accumulation in a similar dose-dependent manner. However, the size of the lipid droplets in BBP-treated cells was significantly larger than those in cells treated with BPA. BBP significantly induced mRNA expression of transcriptional factors C/EBPα and PPARγ, their downstream genes, and numerous adipogenic proteins in a dose and time-dependent manner. Furthermore, GC/MC metabolomic analysis revealed that BBP exposure perturbed the metabolic profiles that are associated with glyceroneogenesis and fatty acid synthesis. Altogether, our current study clearly demonstrates that BBP promoted the differentiation of 3T3-L1 through the activation of the adipogenic pathway and metabolic disturbance. PMID:26820058

  18. Crystal structures of pinoresinol-lariciresinol and phenylcoumaran benzylic ether reductases and their relationship to isoflavone reductases

    Science.gov (United States)

    Min, Tongpil; Kasahara, Hiroyuki; Bedgar, Diana L.; Youn, Buhyun; Lawrence, Paulraj K.; Gang, David R.; Halls, Steven C.; Park, HaJeung; Hilsenbeck, Jacqueline L.; Davin, Laurence B.; Lewis, Norman G.; Kang, ChulHee

    2003-01-01

    Despite the importance of plant lignans and isoflavonoids in human health protection (e.g. for both treatment and prevention of onset of various cancers) as well as in plant biology (e.g. in defense functions and in heartwood development), systematic studies on the enzymes involved in their biosynthesis have only recently begun. In this investigation, three NADPH-dependent aromatic alcohol reductases were comprehensively studied, namely pinoresinol-lariciresinol reductase (PLR), phenylcoumaran benzylic ether reductase (PCBER), and isoflavone reductase (IFR), which are involved in central steps to the various important bioactive lignans and isoflavonoids. Of particular interest was in determining how differing regio- and enantiospecificities are achieved with the different enzymes, despite each apparently going through similar enone intermediates. Initially, the three-dimensional x-ray crystal structures of both PLR_Tp1 and PCBER_Pt1 were solved and refined to 2.5 and 2.2 A resolutions, respectively. Not only do they share high gene sequence similarity, but their structures are similar, having a continuous alpha/beta NADPH-binding domain and a smaller substrate-binding domain. IFR (whose crystal structure is not yet obtained) was also compared (modeled) with PLR and PCBER and was deduced to have the same overall basic structure. The basis for the distinct enantio-specific and regio-specific reactions of PCBER, PLR, and IFR, as well as the reaction mechanism and participating residues involved (as identified by site-directed mutagenesis), are discussed.

  19. Demonstration of Improved Charge Transfer in Graphene/Au Nanorods Plasmonic Hybrids Stabilized by Benzyl Thiol Linkers

    Directory of Open Access Journals (Sweden)

    Giuseppe Valerio Bianco

    2016-01-01

    Full Text Available Hybrids based on graphene decorated with plasmonic gold (Au nanostructures are being investigated as possible materials combination to add to graphene functionalities of tunable plasmon resonance and enhanced absorption at selected wavelength in the visible-near-infrared region of the spectrum. Here, we report a solution drop-casting approach for fabricating stable hybrids based on chemical vapor deposition (CVD graphene and Au nanorods, which are able to activate effective charge transfer from graphene. We demonstrate that CVD graphene functionalization by benzyl thiol (BZT provides the linker to strong anchoring, via S-Au bonds, Au nanorods to graphene. Optical measurements by spectroscopic ellipsometry give evidence of the introduction of plasmon resonances at 1.85 and 2.25 eV in the Au nanorods/BZT/graphene hybrids, which enable surface enhanced Raman scattering (SERS detection. Furthermore, an effective electron transfer from graphene to Au nanorods, resulting in an enhancement of p-type doping of graphene with a consequent decrease of its sheet resistance, is probed by Raman spectroscopy and corroborated by electrical measurements.

  20. Preparation and characterization of inclusion complex of benzyl isothiocyanate extracted from papaya seed with β-cyclodextrin.

    Science.gov (United States)

    Li, Wenzhao; Liu, Xiaoyu; Yang, Qingfeng; Zhang, Ning; Du, Yideng; Zhu, Huaping

    2015-10-01

    The inclusion complex of benzyl isothiocyanate (BITC), extracted from papaya seed with β-cyclodextrin (β-CD), was prepared. Different analytical techniques, such as Fourier transform infrared spectroscopy, thermal analysis, X-ray diffractometry, particle size distribution analysis and (1)H Nuclear magnetic resonance analysis, were used to investigate the characterization of the inclusion complex (BITC-β-CD). All these approaches indicated that the inclusion complex was capable of being formed. The inclusion complex exhibited different spectroscopic and thermodynamic features and properties from BITC, and we deduced the possible inclusion modes for BITC-β-CD. The calculated apparent stability constant of the BITC-β-CD was 600.8l/mol, and the aqueous solubility of BITC was indistinctively improved by phase solubility studies. The results illustrated that β-CD was a proper excipient for increasing the stability and controlled release of BITC. Thus, β-CD complexation technology would be a promising approach, in expanding the application of BITC as a food antibacterial agent. PMID:25872431

  1. Substitution Effects and Linear Free Energy Relationships During Reduction of 4- Benzoyl-n-(4-substituted Benzyl)pyridinium Cations

    Science.gov (United States)

    Leventis, Nicholas; Zhang, Guo-Hui; Rawashdeh, Abdel-Monem M.; Sotiriou-Leventis, Chariklia; Gray, Hugh R. (Technical Monitor)

    2003-01-01

    In analogy to 4-(para-substituted benzoyl)-N-methylpyridinium cations (1-X's), the title species (2-X's, -X = -OCH3, -CH3, -H, -Br, -COCH3, -NO2) undergo two reversible, well-separated (E(sub 1/2) greater than or equal to 650 mV) one-electron reductions. The effect of substitution on the reduction potentials of 2-X's is much weaker than the effect of the same substituents on 1-X's: the Hammett rho-values are 0.80 and 0.93 for the 1st- and 2nd-e reduction of 2-X's vs. 2.3 and 3.3 for the same reductions of 1-X's, respectively. Importantly, the nitro group of 2-NO2 undergoes reduction before the 2nd-e reduction of the 4-benzoylpyridinium system. These results suggest that the redox potentials of the 4-benzoylpyridinium system can be course-tuned via p-benzoyl substitution and fine-tuned via para-benzyl substitution. Introducing the recently derived substituent constant of the -NO2(sup)- group (sigma para-NO2(sup)- = -0.97) yields an excellent correlation for the 3rd-e reduction of 2- NO2 (corresponding to the reduction of the carbonyl group) with the 2nd-e reduction of the other 2-X's, and confirms the electron donating properties of -NO2(sup)-.

  2. A polytetrafluoroethylene porous membrane and dimethylhexadecylamine quaternized poly (vinyl benzyl chloride) composite membrane for intermediate temperature fuel cells

    Science.gov (United States)

    Cao, Yuan-Cheng; Xu, Chenxi; Zou, Linling; Scott, Keith; Liu, Jiyan

    2015-10-01

    A composite material for phosphoric acid (PA) loaded membrane was prepared using a porous polytetrafluoroethylene (PTFE) thin film. N, N-Dimethylhexadecylamine partially quaternized poly (vinyl benzyl chloride) (qPVBzCl-) was synthesized as the substrate for the phosphoric acid loaded polymer membrane. SEM observation indicated that the pores were filled with the qPVBzCl-. The maximum PA loading level was calculated to be 4.67-5.12 per repeat unit on average. TGA results showed that resultant composite membrane was stable in the intermediate temperature from 100 °C to 200 °C. The composite membrane tensile stress was 56.23 MPa, and the Young's Modulus was 0.25 GPa, and the fractured elongation was 23%. The conductivity of the composite membrane after the PA addition (H3PO4@PTFE/qPVBzCl-) increased from 0.085 S cm-1 to 0.11 S cm-1 from 105 °C to 180 °C. The peak power density of the H2/O2 at 175 °C under low humidity condition (PTFE/qPVBzCl- membranes was 360 mW cm-2.

  3. Third-order nonlinearities and structural features in Langmuir-Blodgett films of 1-benzyl-9-hydrofullerene-60

    International Nuclear Information System (INIS)

    Third-order nonlinear susceptibilities χxxxx(3) (-3ω; ω, ω, ω) have been deduced by measuring third-harmonic generation in Langmuir-Blodgett (LB) films of 1-benzyl-9-hydrofullerene-60 (C60-Be). The structural features of the condensed layer at the air-water interface and LB films of the C60-Be were investigated by small angle x-ray diffraction (SAXD) and optical measurements. The third-order nonlinear susceptibilities (χ(3)) were obtained by measuring the THG intensities in LB films of C60-Be and comparing with that of CS2 used as the reference. The value of χxxxx(3) (2.1 x 10-11 esu) was deduced at a 65 nm thick films. The χ(3) is attributed to a three-photon near resonance at the energy level of 29410 cm-1. A new-type of two-chain amphiphilic molecule 1,10-bistearyl-4,6,13, 15-tetra-18-nitrogencrown-6 (NC) was used as insert material to construct mixed C60-Be/NC LB films. Our π-A, UV-visible absorption and SAXD measurements showed that the structural improvement in the mixed C60-Be/NC LB films was realized by insertion of the C60-Be molecules between the two hydrophobic chains of the NC molecules

  4. Preparation of manganese oxide immobilized on SBA-15 by atomic layer deposition as an efficient and reusable catalyst for selective oxidation of benzyl alcohol in the liquid phase

    International Nuclear Information System (INIS)

    Manganese oxide supported on mesoporous silica SBA-15 catalyst (Mn-SBA-15) was tested with Mn contents in the range of 0.8–23 wt%. Samples were prepared by the controlled grafting process of atomic layer deposition (ALD). Other sample was prepared for comparisons by the wet impregnation method. These samples were characterized by the techniques of ICP, XRD, SEM, Raman, FT-IR spectroscopy, diffuse reflectance UV–Vis, TGA-DSC, and N2 absorption–desorption surface area measurement. Results indicated that anchored manganese oxide particles have been successfully synthesized over the surface of SBA-15. These samples contained Red-Ox ion pairs of Mn2+ and Mn3+ highly dispersed on the mesoporous silica surface. The impregnated sample exhibited lower surface area and contained Red-Ox ion pairs of Mn3+ and Mn4+ more aggregated particles on the SBA-15 surface. Results determined Mn-SBA-15 as an efficient and selective catalyst for oxidation of benzyl alcohol with tert-butylhydroperoxide in liquid phase. In accordance with expectations, there was a negligible amount of leaching of immobilized manganese oxide from the support during the reaction, because of strong surface interaction between manganese oxide and hydroxyls groups. The influences of reaction temperature, reaction time, solvent, TBHP/benzyl alcohol molar ratio, amount of catalyst and reusability were investigated. Under optimized conditions (0.2 g catalyst, TBHP/benzyl alcohol molar ratio 1, solvent acetonitrile; T = 90 °C; reaction time 8 h), results achieved 70% conversion of benzyl alcohol and 100% selectivity to benzaldehyde. - Highlights: • Manganese oxide immobilized on SBA-15 were prepared by atomic layer deposition (ALD). • Oxidation of benzyl alcohol to benzaldehyde over this catalyst were investigated. • Effects of loading of manganese oxide, T, oxidant/alcohol ratio were investigated. • The leaching of manganese oxide from support during the reaction was negligible. • Under optimized

  5. Preparation of manganese oxide immobilized on SBA-15 by atomic layer deposition as an efficient and reusable catalyst for selective oxidation of benzyl alcohol in the liquid phase

    Energy Technology Data Exchange (ETDEWEB)

    Mahdavi, Vahid, E-mail: v-mahdavi@araku.ac.ir; Mardani, Mahdieh

    2015-04-01

    Manganese oxide supported on mesoporous silica SBA-15 catalyst (Mn-SBA-15) was tested with Mn contents in the range of 0.8–23 wt%. Samples were prepared by the controlled grafting process of atomic layer deposition (ALD). Other sample was prepared for comparisons by the wet impregnation method. These samples were characterized by the techniques of ICP, XRD, SEM, Raman, FT-IR spectroscopy, diffuse reflectance UV–Vis, TGA-DSC, and N{sub 2} absorption–desorption surface area measurement. Results indicated that anchored manganese oxide particles have been successfully synthesized over the surface of SBA-15. These samples contained Red-Ox ion pairs of Mn{sup 2+} and Mn{sup 3+} highly dispersed on the mesoporous silica surface. The impregnated sample exhibited lower surface area and contained Red-Ox ion pairs of Mn{sup 3+} and Mn{sup 4+} more aggregated particles on the SBA-15 surface. Results determined Mn-SBA-15 as an efficient and selective catalyst for oxidation of benzyl alcohol with tert-butylhydroperoxide in liquid phase. In accordance with expectations, there was a negligible amount of leaching of immobilized manganese oxide from the support during the reaction, because of strong surface interaction between manganese oxide and hydroxyls groups. The influences of reaction temperature, reaction time, solvent, TBHP/benzyl alcohol molar ratio, amount of catalyst and reusability were investigated. Under optimized conditions (0.2 g catalyst, TBHP/benzyl alcohol molar ratio 1, solvent acetonitrile; T = 90 °C; reaction time 8 h), results achieved 70% conversion of benzyl alcohol and 100% selectivity to benzaldehyde. - Highlights: • Manganese oxide immobilized on SBA-15 were prepared by atomic layer deposition (ALD). • Oxidation of benzyl alcohol to benzaldehyde over this catalyst were investigated. • Effects of loading of manganese oxide, T, oxidant/alcohol ratio were investigated. • The leaching of manganese oxide from support during the reaction was

  6. Role of oxygen free radicals in patients with acute pancreatitis

    OpenAIRE

    Park, Byung Kyu; Chung, Jae Bock; Lee, Jin Heon; Suh, Jeong Hun; Park, Seung Woo; Song, Si Young; Kim, Hyeyoung; Kim, Kyung Hwan; Kang, Jin Kyung

    2003-01-01

    AIM: The generation of oxygen free radicals has been implicated in the pathogenesis of experimental pancreatitis. The aim of this study was to determine the role of oxygen free radicals in patients with acute pancreatitis.

  7. Free radicals, antioxidants and functional foods: Impact on human health

    OpenAIRE

    Lobo, V.; Patil, A.; A Phatak; N Chandra

    2010-01-01

    In recent years, there has been a great deal of attention toward the field of free radical chemistry. Free radicals reactive oxygen species and reactive nitrogen species are generated by our body by various endogenous systems, exposure to different physiochemical conditions or pathological states. A balance between free radicals and antioxidants is necessary for proper physiological function. If free radicals overwhelm the body's ability to regulate them, a condition known as oxidative stress...

  8. The Serbian Radical movement 1881-1903: A historical aspect

    OpenAIRE

    Protić Milan St.

    2005-01-01

    Focusing on the initial stage (until 1903) of the Serbian Radical movement the paper attempts to delineate and explicate the main phases of its political maturation. In its initial stage Serbian Radicalism passed through several significant phases. The earliest phase (1869-80) may be named the period of rudimentary Radicalism. The movement was unorganized and oscillated between the ideas of socialism, anarchism and peasant democracy. The year 1881 saw the founding of the Radical Party as the ...

  9. Synthesis of glycopolymer architectures by reversible-deactivation radical polymerization

    OpenAIRE

    Ali Ghadban; Luca Albertin

    2013-01-01

    This review summarizes the state of the art in the synthesis of well-defined glycopolymers by Reversible-Deactivation Radical Polymerization (RDRP) from its inception in 1998 until August 2012. Glycopolymers architectures have been successfully synthesized with four major RDRP techniques: Nitroxide-mediated radical polymerization (NMP), cyanoxyl-mediated radical polymerization (CMRP), atom transfer radical polymerization (ATRP) and reversible addition-fragmentation chain transfer (RAFT) polym...

  10. Inguinal hernia developed after radical retropubic surgery for prostate cancer

    OpenAIRE

    Chung, Choon Sik; Jeong, Gyu Young; Kim, Seung Han; Lee, Dong Keun

    2013-01-01

    Purpose In this retrospective study, we aimed to compare the clinical characteristics of inguinal hernia developed after radical retropubic surgery for prostate cancer to the hernia without previous radical prostatectomy. Methods Twenty-three patients (group A) who had radical retropubic surgery for prostate cancer underwent laparoscopic or open tension-free inguinal hernia repair from March 2007 to February 2011. Nine hundred and forty patients (group B) without previous radical retropubic s...

  11. Hybrid radical energy storage device and method of making

    Energy Technology Data Exchange (ETDEWEB)

    Gennett, Thomas; Ginley, David S.; Braunecker, Wade; Ban, Chunmei; Owczarczyk, Zbyslaw

    2016-04-26

    Hybrid radical energy storage devices, such as batteries or electrochemical devices, and methods of use and making are disclosed. Also described herein are electrodes and electrolytes useful in energy storage devices, for example, radical polymer cathode materials and electrolytes for use in organic radical batteries.

  12. Radical radiotherapy for carcinoma of the vulva

    Energy Technology Data Exchange (ETDEWEB)

    Slevin, N.J.; Pointon, R.C.S.

    1989-02-01

    A study was made of 58 patients with carcinoma of the vulva treated by radical radiotherapy between 1965 and 1982. The choice of treatment technique was influenced by site and extent of disease as well as the general condition of the patient. The crude 5-year survival was 26% (15/58). Local control was achieved in 40% of cases and was associated with tumour size of 4 cm or less. Radionecrosis occurred in nine cases but none of these required surgical intervention. Surgery remains the treatment of choice for carcinoma of the vulva. This report emphasizes that radical radiotherapy has a curative potential in those cases considered unsuitable for surgery and that the necrosis type and rate are within the limits of acceptable morbidity.

  13. Radical radiotherapy for carcinoma of the vulva

    International Nuclear Information System (INIS)

    A study was made of 58 patients with carcinoma of the vulva treated by radical radiotherapy between 1965 and 1982. The choice of treatment technique was influenced by site and extent of disease as well as the general condition of the patient. The crude 5-year survival was 26% (15/58). Local control was achieved in 40% of cases and was associated with tumour size of 4 cm or less. Radionecrosis occurred in nine cases but none of these required surgical intervention. Surgery remains the treatment of choice for carcinoma of the vulva. This report emphasizes that radical radiotherapy has a curative potential in those cases considered unsuitable for surgery and that the necrosis type and rate are within the limits of acceptable morbidity. (author)

  14. Editorial: RADICALISM AND POLITICS OF RELIGION

    Directory of Open Access Journals (Sweden)

    Editorial Al-Jami'ah: Journal of Islamic Studies

    2008-02-01

    Full Text Available Radical Islamism has become the “sexiest” issue in the international scholarship of religion since the September 11 tragedy in 2001. It has been associated with a number of terrorist attacks not only in the West but also in Muslim countries. Every single of radical Islamism has caught the interest of not only scholars and policy makers but also general public. Interestingly, the general assumption that religion is the source of peace has been seriously challenged, not by non-religious communities, but by the violent practices of particular religious groups, however small they are. Indeed, there are certain groups striving for Islam but by using acts which could give awful image on Islam itself and against humanity.

  15. EPR study of free radicals in bread

    Science.gov (United States)

    Yordanov, Nicola D.; Mladenova, Ralitsa

    2004-05-01

    The features of the recorded EPR spectra of paramagnetic species formed in bread and rusk are reported. The appearance of free radicals in them is only connected with their thermal treatment since the starting materials (flour and grains) exhibit very weak EPR signal. The obtained EPR spectra are complex and indicate that: (i) the relative number of paramagnetic species depends on the temperature and treating time of the raw product; (ii) the g-values are strongly temperature dependent with a tendency to coincide at t≥220 °C. Because of the relatively low (150-220 °C) temperature of thermal treatment, the studied free radicals can be assumed to appear in the course of the browning (Maillard) reaction and not to the carbonization of the material.

  16. Anion photoelectron spectroscopy of radicals and clusters

    Energy Technology Data Exchange (ETDEWEB)

    Travis, Taylor R.

    1999-12-16

    Anion photoelectron spectroscopy is used to study free radicals and clusters. The low-lying {sup 2}{Sigma} and {sup 2}{Pi} states of C{sub 2n}H (n = 1--4) have been studied. The anion photoelectron spectra yielded electron affinities, term values, and vibrational frequencies for these combustion and astrophysically relevant species. Photoelectron angular distributions allowed the author to correctly assign the electronic symmetry of the ground and first excited states and to assess the degree of vibronic coupling in C{sub 2}H and C{sub 4}H. Other radicals studied include NCN and I{sub 3}. The author was able to observe the low-lying singlet and triplet states of NCN for the first time. Measurement of the electron affinity of I{sub 3} revealed that it has a bound ground state and attachment of an argon atom to this moiety enabled him to resolve the symmetric stretching progression.

  17. Radical Scavenging Effects of Different Veronica species

    OpenAIRE

    Ummuhan Şebnem Harput; Yasin Genç; Newaj Khan; İclal Saracoglu

    2011-01-01

    It is well known that the excessive production of reactive oxygen species is hazardous for living organisms and damages major cellular constituents such as DNA, lipid and protein. To find new products reducing free radical damage is very important researches in recent pharmaceutical investigations. Considering this information, fourteen Veronica species are decided to research in the view point of their antioxidant capacity and the chemical content. Water extracts of the plants were tested fo...

  18. Ultraviolet photodissociation dynamics of the cyclohexyl radical

    Science.gov (United States)

    Lucas, Michael; Liu, Yanlin; Zhang, Jingsong

    2015-03-01

    Cycloalkanes are important components in conventional fuels and oil shale derived fuels and the combustion of cyclohexane fuels leads to the production of benzene, a pollutant precursor. One of the pathways from cyclohexane to benzene is through sequential hydrogen loss, including the cyclohexyl radical as an intermediate. The ultraviolet (UV) photodissociation dynamics of the cyclohexyl (c-C6H11) radical was studied for the first time using the high- n Rydberg atom time-of-flight (HRTOF) technique in the range of 232-262 nm. The translational energy distributions of the H-atom loss product channel, P (ET) 's, show a large translational energy release and a large fraction of average translational energy in the total excess energy, , from 232-262 nm. The H-atom product angular distribution is anisotropic with a positive β parameter. The most likely H-atom loss pathway is an axial H ejection from the β-carbon in cyclohexyl to form cyclohexene + H, which along with the positive β parameter, indicates that the transition dipole moment, μ, is perpendicular to the ring. The P (ET) and anisotropy of the H-atom loss product channel are significantly larger than those expected for a statistical unimolecular dissociation of a hot radical, indicating a non-statistical dissociation mechanism. The dissociation mechanism is consistent with direct dissociation on a repulsive excited state surface or on the repulsive part of the ground state surface to produce cyclohexene + H, possibly mediated by a conical intersection. Cyclohexyl is the largest radical so far showing a direct dissociation mechanism.

  19. Computed tomography after radical pancreaticoduodenectomy (Whipple's procedure)

    International Nuclear Information System (INIS)

    Whipple's procedure (radical pancreaticoduodenectomy) is currently the only curative option for patients with periampullary malignancy. The surgery is highly complex and involves multiple anastomoses. Complications are common and can lead to significant postoperative morbidity. Early detection and treatment of complications is vital, and high-quality multidetector computed tomography (MDCT) is currently the best method of investigation. This review outlines the surgical technique and illustrates the range of normal postoperative appearances together with the common complications

  20. EI igualitarismo radical de John Rawls

    OpenAIRE

    Rodríguez Zepeda, Jesús

    2004-01-01

    The main purpose of this paper is to offer an interpretation of the canonical statement of justice as fairness (A Theory of Justice) as a deeply egalitarian, even radical, argument. In order to do so, the categories of justice as fairness strongly related to the egalitarian and distributive meaning of the rawlsian liberal model and, specifically, those aimed to solve the problem of social justice, are accurately revised, namely, the fair equality of opportunity and the diff...

  1. The radical of a vertex operator algebra

    OpenAIRE

    Dong, C.; Li, H.; Mason, G.; Montague, P

    1996-01-01

    The radical $J(V)$ of a vertex operator algebra $V$ is defined to be the subspace of $V$ consisting of vectors $v$ such that the zero mode $o(v)=0$ on $V$ where $o(v)=v_{wt v-1}$ if $v$ is homogeneous. We establish various facts about $o(v),$ including the determination of $J(V)$ which is shown to be essentially equal to $(L(0)+L(-1))V.$

  2. AQUEOUS STABLE FREE RADICAL POLYMERIZATION PROCESSES

    Institute of Scientific and Technical Information of China (English)

    Andrea R. Szkurhan; Michael K. Georges

    2004-01-01

    An overview of aqueous polymerizations, which include emulsion, miniemulsion and suspension polymerizations,under stable free radical polymerization (SFRP) conditions is presented. The success of miniemulsion and suspension SFRP polymerizations is contrasted with the difficulties associated with obtaining a stable emulsion polymerization. A recently developed unique microprecipitation technique is referenced as a means of making submicron sized particles that can be used to achieve a stable emulsion SFRP process.

  3. EARLY POSTOPERATIVE COMPLICATIONS AFTER RADICAL CYSTECTOMY

    Directory of Open Access Journals (Sweden)

    V. O. Mager

    2014-08-01

    Full Text Available Radical cystectomy (RCE is associated with a considerable number of early postoperative complications as before. Based on 10 years’ experience, this paper demonstrates the frequency (33.9 % and types of early complications following RCE, as well as postoperative mortality (5.5 % and its resulting causes. Although postoperative mortality is relatively low today, the frequency of early postoperative complications remains high as before.

  4. International Radical Cystectomy Consortium: A way forward

    OpenAIRE

    Raza, Syed Johar; Field, Erinn; Kibel, Adam S.; Mottrie, Alex; Weizer, Alon Z; Wagner, Andrew; Hemal, Ashok K.; Scherr, Douglas S.; Schanne, Francis; Gaboardi, Franco; Wu, Guan; Peabody, James O.; Koauk, Jihad; Redorta, Joan Palou; Pattaras, John G.

    2014-01-01

    Robot-assisted radical cystectomy (RARC) is an emerging operative alternative to open surgery for the management of invasive bladder cancer. Studies from single institutions provide limited data due to the small number of patients. In order to better understand the related outcomes, a world-wide consortium was established in 2006 of patients undergoing RARC, called the International Robotic Cystectomy Consortium (IRCC). Thus far, the IRCC has reported its findings on various areas of operativ...

  5. Learning Curve of Robotic Radical Prostatectomy

    OpenAIRE

    Muhammed Ersagun Arslan; Abdullah Erdem Canda; Ali Fuat Atmaca; Mevlana Derya Balbay; Ziya Akbulut; Serkan Altinova; Ahmet Tunc Ozdemir

    2015-01-01

    Introduction: Prostate cancer (PrC) is the fifth most common malignancy worldwide and the second most common malignancy in men. Currently, robotic-assisted laparoscopic radical prostatectomy (RARP) has become a popular treatment for localised PrC treatment worldwide. We aimed to assess the learning curve of RARP in our institution. Methods: A total of 391 patients who underwent RARP in our clinic between February 2009 and April 2013 were included in the study. We retrospectively evaluated ...

  6. Synthesis of Polymer Grafted Magnetite Nanoparticle with the Highest Grafting Density via Controlled Radical Polymerization

    OpenAIRE

    Babu Kothandapani; Dhamodharan Raghavachari

    2009-01-01

    Abstract The surface-initiated ATRP of benzyl methacrylate, methyl methacrylate, and styrene from magnetite nanoparticle is investigated, without the use of sacrificial (free) initiator in solution. It is observed that the grafting density obtained is related to the polymerization kinetics, being higher for faster polymerizing monomer. The grafting density was found to be nearly 2 chains/nm2for the rapidly polymerizing benzyl methacrylate. In contrast, for the less rapidly polymerizing styren...

  7. Chemical Nonlinearities and Radical Pair Lifetime Estimation

    Science.gov (United States)

    Robinson, Gregory

    2013-03-01

    Much attention has recently developed around chemical reactions that depend on applied static magnetic fields as weak as earth's. This interest is largely motivated by experiments that implicate the role of spin-selective radical pair recombination in biological magnetic sensing. Existing literature uses a straightforward calculation to approximate the expected lifetime of coherent radical pairs as a function of the minimum RF amplitude that is observed to disrupt magnetic navigation, apparently by decohering the radical pair via electronic Zeeman excitations. But we show that chemical nonlinearities can preclude direct computation of coherent pair lifetime without considering the cellular signalling mechanisms involved, and discuss whether it can explain the surprising fragility of some animals' compass sense. In particular, we demonstrate that an autocatalytic cycle can introduce threshold effects on the disruption sensitivity to applied oscillatory magnetic fields. We will show examples in the mean-field limit and consider the consequences of noise and fluctuations in the Freidlin-Wentzell picture of perturbed dynamical systems.

  8. Complications of Radical Cystectomy and Orthotopic Reconstruction

    Directory of Open Access Journals (Sweden)

    Wei Shen Tan

    2015-01-01

    Full Text Available Radical cystectomy and orthotopic reconstruction significant morbidity and mortality despite advances in minimal invasive and robotic technology. In this review, we will discuss early and late complications, as well as describe efforts to minimize morbidity and mortality, with a focus on ileal orthotopic bladder substitute (OBS. We summarise efforts to minimize morbidity and mortality including enhanced recovery as well as early and late complications seen after radical cystectomy and OBS. Centralisation of complex cancer services in the UK has led to a fall in mortality and high volume institutions have a significantly lower rate of 30-day mortality compared to low volume institutions. Enhanced recovery pathways have resulted in shorter length of hospital stay and potentially a reduction in morbidity. Early complications of radical cystectomy occur as a direct result of the surgery itself while late complications, which can occur even after 10 years after surgery, are due to urinary diversion. OBS represents the ideal urinary diversion for patients without contraindications. However, all patients with OBS should have regular long term follow-up for oncological surveillance and to identify complications should they arise.

  9. Radical correction of Budd-Chiari syndrome

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-qiang; WANG Zhong-gao; MENG Qing-you; SANG Hong-fei; QIAN Ai-min; DUAN Peng-fei; RONG Jian-jie

    2007-01-01

    Background Interventional therapy is widely accepted as the first choice for the treatment of the Budd-Chiari syndrome,but the use of radical correctional therapy should not be discarded. This study describes radical correction by controlling bleeding from distal end of pathological segment of the inferior vena cava (IVC) and discusses potential surgical errors and postoperative complications.Methods Of the 216 patients in the study, 78 were treated with simple membranectomy, 64 with dissection of the pathological segment of the IVC and vascular prosthesis or pericardial patch plasty, 60 with resection of the pathological segment of the IVC and orthotopic graft transplantation with vascular prosthesis, and 14 with resection of the occlusive main hepatic vein and its upper IVC, hepatic venous outflow plasty and vascular prosthesis orthotopic graft transplantation from the hepatic venous entrance to the IVC of right atrial ostium.Results Except 14 cases who were discharged after hepatic vein outflow plasty, four cases died postoperatively, and 198 patients were discharged without complications. The symptoms of 15 patients were relieved partially and 2 without any change. There were no deaths intraoperatively. Of the 112 cases who were followed up for 72 months, 13 suffered from a relapse.Conclusions Radical correction is a beneficial therapy in the treatment of Budd-Chiari syndrome.

  10. Radical inactivation of a biological sulphydryl molecule

    International Nuclear Information System (INIS)

    Reactive species produced from the free radical-induced chain oxidation of low molecular weight sulphydryl-containing molecules in aerated solutions deactivate the sulphydryl-containing enzyme papain, forming both reparable mixed disulphides and non-reparable products. This inactivation is highly efficient for penicillamine and glutathione, but almost negligible with cysteine, which is a protector of papain for [cysteine] / [papain] >= 5 under all conditions used. In the case of glutathione, superoxide dismutase caused only a small reduction in the inactivation and peroxide yields were small, implying that the deactivating species are not .O2- but RSOO. radicals or products from them. For penicillamine, however, dimutase was highly effective and the peroxide yields were relatively large, demonstrating that .O2- or a radical with similar capabilities for forming H2O2 and being deactivated by dismutase was involved. Although in the presence of dismutase penicillamine is a better protector of non-reparable papain inactivation than glutathione, it suffers from a deficiency in that the papain-penicillamine mixed disulphide, which is always formed, cannot be repaired by spontaneous reaction with RSH molecules. (author)

  11. The detection of hydroxyl radicals in vivo.

    Science.gov (United States)

    Freinbichler, Wolfhardt; Bianchi, Loria; Colivicchi, M Alessandra; Ballini, Chiara; Tipton, Keith F; Linert, Wolfgang; Corte, Laura Della

    2008-01-01

    Several indirect methods have been developed for the detection and quantification of highly reactive oxygen species (hROS), which may exist either as free hydroxyl radicals, bound "crypto" radicals or Fe(IV)-oxo species, in vivo. This review discusses the strengths and weaknesses associated with those most commonly used, which determine the hydroxylation of salicylate or phenylalanine. Chemical as well as biological arguments indicate that neither the hydroxylation of salicylate nor that of phenylalanine can guarantee an accurate hydroxyl radical quantitation in vivo. This is because not all hydroxylated product-species can be used for detection and the ratio of these species strongly depends on the chemical environment and on the reaction time. Furthermore, at least in the case of salicylate, the high concentrations of the chemical trap required (mM) are known to influence biological processes associated with oxidative stress. Two, newer, alternative methods described, the 4-hydroxy benzoic acid (4-HBA) and the terephthalate (TA) assays, do not have these drawbacks. In each case reaction with hROS leads to only one hydroxylated product. Thus, from a chemical viewpoint, they should provide a better hROS quantitation. Further work is needed to assess any possible biological effects of the required millimolar (4-HBA) and micromolar (TA) concentrations of the chemical traps. PMID:18262275

  12. Formation of long-lived radicals on proteins by radical transfer from heme enzymes--a common process?

    DEFF Research Database (Denmark)

    Ostdal, H; Andersen, H J; Davies, Michael Jonathan

    1999-01-01

    albumin via the heme edge of the peroxidase. In contrast, albumin radical formation by the HRP/H2O2/free tyrosine system was only marginally affected by proteolysis, consistent with free tyrosine phenoxyl radicals being the mediators of radical transfer, without significant protein-protein interaction...

  13. Generation of acetyl free radicals by radiolysis: comparison of free radicals generated from acetaldehyde and ethylene-glycol

    International Nuclear Information System (INIS)

    The optical absorption spectra of the intermediates obtained by pulse radiolysis of N2O-saturated solutions of acetaldehyde or ethylene-glycol and the kinetics of their decays have been investigated. Results suggest that the OH· radical reactions with acetaldehyde or ethylene-glycol produce acetyl and formylmethyl radicals. Besides, these radicals are shown to reduce ferricytochrome c

  14. Spatial features of radical reactions in irradiated solids

    International Nuclear Information System (INIS)

    The Electron Spin Echo (ESE) method is used to obtain data on the spatial distribution of radical particles originated in irradiated solid matrices from two types of precursors: ionized molecules (R+-type radicals), and secondary electrons (R--type radicals). For methanol with Cd+2 acceptors and for water solutions of acids and alkalis the radical tracks are shown to have a complex structure. Possible reasons for long path lengths of secondary electrons in polar media are analyzed. Pair distribution functions, as well as their changes due to diffusion and chemical reactions, are reported for radicals generated by photolysis and radiolysis. (author)

  15. Progress in measurement of free radicals in biological systems

    International Nuclear Information System (INIS)

    Free radicals generation and oxidative stress are involved in many pathological processes including neuro-degenerated diseases, diabetes, tumorigenesis and radiation damage. Measurement of free radicals is of importance in the field of radiation protection and radiation damage. The electron spinning resonance (ESR) techniques for measurement of free radicals in biological systems are summarized according to the literature and the author's research work in this review. The recent emerging immuno-spin trapping method for analysis of protein radicals and DNA radicals is also introduced. (authors)

  16. Peroxy radical chemistry and OH radical production during the NO3-initiated oxidation of isoprene

    Directory of Open Access Journals (Sweden)

    P. O. Wennberg

    2012-01-01

    Full Text Available Peroxy radical reactions (RO2 + RO2 from the NO3-initiated oxidation of isoprene are studied with both gas chromatography and a chemical ionization mass spectrometry technique that allows for more specific speciation of products than in previous studies of this system. We find high nitrate yields (>~80%, consistent with other studies. We further see evidence of significant hydroxyl radical (OH formation in this system, which we propose comes from RO2 + HO2 reactions with a yield of ~42–62%. An additional OH source is the second generation oxidation of the nitrooxyhydroperoxide, which produces OH and a dinitrooxyepoxide with a yield of ~35%. The branching ratio of the radical propagating, carbonyl- and alcohol-forming, and dimer-forming channels of the RO2 + RO2 reaction are found to be ~18–38%, ~59–77%, and ~3–4%, respectively. HO2 formation in this system is lower than has been previously assumed. Addition of RO2 to isoprene is suggested as a possible route to the formation of several isoprene dimer compounds (ROOR. The nitrooxy, allylic, and C5 peroxy radicals present in this system exhibit different behavior than the limited suite of peroxy radicals that have been studied to date.

  17. Inactivation efficiencies of radical reactions with biologically active DNA

    Science.gov (United States)

    Lafleur, M. V. M.; Retèl, J.; Loman, H.

    Dilute aqueous solutions of biologically active θX174 DNA may serve as a simplified model system of the cell. Damage to the DNA after irradiation with γ-rays, may be ascribed to reactions with .OH, .H and e -aq or secondary radicals, arising from reactions of water radicals with added scavengers. Conversion of primary (water) radicals into secondary (scavenger) radicals leads to a considerable protection of the DNA, which, however, would have been larger if these secondary radicals did not contribute to DNA inactivation. The inactivation yield due to isopropanol or formate (secondary) radicals depends on dose rate as well as DNA concentration. Furthermore the inactivation efficiencies of the reactions of both the primary and the secondary radicals with single-stranded DNA could be established.

  18. Benzyl-N-acetyl-alpha-D-galactosaminide induces a storage disease-like phenotype by perturbing the endocytic pathway.

    Science.gov (United States)

    Ulloa, Fausto; Real, Francisco X

    2003-04-01

    The sugar analog O-benzyl-N-acetyl-alpha-d-galactosaminide (BG) is an inhibitor of glycan chain elongation and inhibits alpha2,3-sialylation in mucus-secreting HT-29 cells. Long-term exposure of these cells to BG is associated with the accumulation of apical glycoproteins in cytoplasmic vesicles. The mechanisms involved therein and the nature of the vesicles have not been elucidated. In these cells, a massive amount of BG metabolites is synthesized. Because sialic acid is mainly distributed apically in epithelial cells, it has been proposed that the BG-induced undersialylation of apical membrane glycoproteins is responsible for their intracellular accumulation due to a defect in anterograde traffic and that sialic acid may constitute an apical targeting signal. In this work, we demonstrate that the intracellular accumulation of membrane glycoproteins does not result mainly from defects in anterograde traffic. By contrast, in BG-treated cells, endocytosed membrane proteins were retained intracellularly for longer periods of time than in control cells and colocalized with accumulated MUC1 and beta(1) integrin in Rab7/lysobisphosphatidic acid(+) vesicles displaying features of late endosomes. The phenotype of BG-treated cells is reminiscent of that observed in lysosomal storage disorders. Sucrose induced a BG-like, lysosomal storage disease-like phenotype without affecting sialylation, indicating that undersialylation is not a requisite for the intracellular accumulation of membrane glycoproteins. Our findings strongly support the notion that the effects observed in BG-treated cells result from the accumulation of BG-derived metabolites and from defects in the endosomal pathway. We propose that abnormal subcellular distribution of membrane glycoproteins involved in cellular communication and/or signaling may also take place in lysosomal storage disorders and may contribute to their pathogenesis. PMID:12538583

  19. Radical intermediates involved in the bleaching of the carotenoid crocin. Hydroxyl radicals, superoxide anions and hydrated electrons

    Energy Technology Data Exchange (ETDEWEB)

    Bors, W.; Saran, M.; Michel, C. (Gesellschaft fuer Strahlen- und Umweltforschung m.b.H. Muenchen, Neuherberg (Germany, F.R.). Abt. Strahlenbiologie)

    1982-05-01

    The participation of the primary radicals in the bleaching of aqueous solutions of the carotenoid crocin by ionizing radiation was investigated, employing both X-radiolysis and pulse radiolysis. The pulse-radiolytic data demonstrated a very rapid diffusion-controlled attack by both hydroxyl radicals (radicalsOH) and hydrated electrons (e/sup -/sub(aq)), while superoxide anions (O/sub 2//sup -/) did not react at all. The site of the initial reaction of these radicals was not limited to the polyene chromophore. Slower secondary reactions involving crocin alkyl or peroxy radicals contribute mainly to the overall bleaching, in particular during steady-state irradiation.

  20. Radical intermediates involved in the bleaching of the carotenoid crocin. Hydroxyl radicals, superoxide anions and hydrated electrons

    International Nuclear Information System (INIS)

    The participation of the primary radicals in the bleaching of aqueous solutions of the carotenoid crocin by ionizing radiation was investigated, employing both X-radiolysis and pulse radiolysis. The pulse-radiolytic data demonstrated a very rapid diffusion-controlled attack by both hydroxyl radicals (radicalsOH) and hydrated electrons (e-sub(aq)), while superoxide anions (O2-) did not react at all. The site of the initial reaction of these radicals was not limited to the polyene chromophore. Slower secondary reactions involving crocin alkyl or peroxy radicals contribute mainly to the overall bleaching, in particular during steady-state irradiation. (author)

  1. Picosecond Control of Photogenerated Radical Pair Lifetimes Using a Stable Third Radical.

    Science.gov (United States)

    Horwitz, Noah E; Phelan, Brian T; Nelson, Jordan N; Krzyaniak, Matthew D; Wasielewski, Michael R

    2016-05-12

    Photoinduced electron transfer reactions in organic donor-acceptor systems leading to long-lived radical ion pairs (RPs) have attracted broad interest for their potential applications in fields as diverse as solar energy conversion and spintronics. We present the photophysics and spin dynamics of an electron donor - electron acceptor - stable radical system consisting of a meta-phenylenediamine (mPD) donor covalently linked to a 4-aminonaphthalene-1,8-dicarboximide (ANI) electron-accepting chromophore as well as an α,γ-bisdiphenylene-β-phenylallyl (BDPA) stable radical. Selective photoexcitation of ANI produces the BDPA-mPD(+•)-ANI(-•) triradical in which the mPD(+•)-ANI(-•) RP spins are strongly exchange coupled. The presence of BDPA is found to greatly increase the RP intersystem crossing rate from the initially photogenerated BDPA-(1)(mPD(+•)-ANI(-•)) to BDPA-(3)(mPD(+•)-ANI(-•)), resulting in accelerated RP recombination via the triplet channel to produce BDPA-mPD-(3*)ANI as compared to a reference molecule lacking the BDPA radical. The RP recombination rates observed are much faster than those previously reported for weakly coupled triradical systems. Time-resolved EPR spectroscopy shows that this process is also associated with strong spin polarization of the stable radical. Overall, these results show that RP intersystem crossing rates can be strongly influenced by stable radicals nearby strongly coupled RP systems, making it possible to use a third spin to control RP lifetimes down to a picosecond time scale. PMID:27108738

  2. Radical hysterectomy with adjuvant radiotherapy versus radical radiotherapy for FIGO stage IIB cervical cancer

    International Nuclear Information System (INIS)

    The goal of this study was to compare treatment outcomes for Federation of Gynecology and Obstetrics (FIGO) stage IIB cervical carcinoma patients receiving radical surgery followed by adjuvant postoperative radiotherapy versus radical radiotherapy. Medical records of FIGO stage IIB cervical cancer patients treated between July 2008 and December 2011 were retrospectively reviewed. A total of 148 patients underwent radical hysterectomy with pelvic lymph node dissection followed by adjuvant radiotherapy (surgery-based group). These patients were compared with 290 patients that received radical radiotherapy alone (RT-based group). Recurrence rates, progression-free survival (PFS), overall survival (OS), local control rates, and treatment-related complications were compared for these two groups. Similar rates of recurrence (16.89% vs. 12.41%, p = 0.200), PFS (log-rank, p = 0.211), OS (log-rank, p = 0.347), and local control rates (log-rank, p = 0.668) were observed for the surgery-based group and the RT-based group, respectively. Moreover, the incidence of acute grade 3–4 gastrointestinal reactions and late grade 3–4 lower limb lymphedema were significantly higher for the surgery-based group versus the RT-based group. Cox multivariate analyses found no significant difference in survival outcome between the two groups, and tumor diameter and histopathology were identified as significant prognostic factors for OS. Radical radiotherapy was associated with fewer treatment-related complications and achieved comparable survival outcomes for patients with FIGO stage IIB cervical cancer compared to radical hysterectomy followed by postoperative radiotherapy

  3. Spectroscopy of free-base N-confused tetraphenylporphyrin radical anion and radical cation.

    Science.gov (United States)

    Alemán, Elvin A; Manríquez Rocha, Juan; Wongwitwichote, Wongwit; Godínez Mora-Tovar, Luis Arturo; Modarelli, David A

    2011-06-23

    The radical anions and radical cations of the two tautomers (1e and 1i) of 5,10,15,20-tetraphenyl N-confused free-base porphyrin have been studied using a combination of cyclic voltammetry, steady state absorption spectroscopy, and computational chemistry. N-Confused porphyrins (NCPs), alternatively called 2-aza-21-carba-5,10,15,20-tetraphenylporphyrins or inverted porphyrins, are of great interest for their potential as building blocks in assemblies designed for artificial photosynthesis, and understanding the absorption spectra of the corresponding radical ions is paramount to future studies in multicomponent arrays where electron-transfer reactions are involved. NCP 1e was shown to oxidize at a potential of E(ox) 0.65 V vs Fc(+)|Fc in DMF and reduce at E(red) -1.42 V, while the corresponding values for 1i in toluene were E(ox) 0.60 V and E(red) -1.64 V. The geometries of these radical ions were computed at the B3LYP/6-31+G(d)//B3LYP/6-31G(d) level in the gas phase and in solution using the polarizable continuum model (PCM). From these structures and that of H(2)TPP and its corresponding radical ions, the computed redox potentials for 1e and 1i were calculated using the Born-Haber cycle. While the computed reduction potentials and electron affinities were in excellent agreement with the experimental reduction potentials, the calculated oxidation potentials displayed a somewhat less ideal relationship with experiment. The absorption spectra of the four radical ions were also measured experimentally, with radical cations 1e(•+) and 1i(•+) displaying significant changes in the Soret and Q-band regions as well as new low energy absorption bands in the near-IR region. The changes in the absorption spectra of radical anions 1e(•-) and 1i(•-) were not as dramatic, with the changes occurring only in the Soret and Q-band regions. These results were favorably modeled using time-dependent density functional calculations at the TD-B3LYP/6-31+G(d)//B3LYP/6-31G

  4. Uma análise behaviorista radical dos sonhos A radical behaviorist analysis of the dreams

    OpenAIRE

    Francynete Melo e Silva

    2000-01-01

    Embora não haja um consenso acerca de questões sobre o que são os sonhos, porque sonhamos, etc., a maioria dos estudos sobre a natureza dos sonhos concorda que ela está relacionada a condições internas do organismo. Contrariamente, o behaviorismo radical analisa os sonhos como comportamentos privados, sendo produtos das histórias filogenética, ontogenética e cultural. Neste sentido, este trabalho tem como objetivo analisar os sonhos a partir da perspectiva behaviorista radical, considerando-o...

  5. Studies of radiation-produced radicals and radical ions. Progress report, September 1, 1982-August 31, 1983

    International Nuclear Information System (INIS)

    During the past year, radiation chemical and solid-state ESR techniques were combined to generate and characterize novel radical ions. Observations have been made on a variety of metastable organometallic radical cations derived from Group IV B metal alkyls. Matrix interactions have been discovered between radical cations and the Freon solvent. The radical cation formed from ethylene oxide is the ring-opened 2-oxa-trimethylene cation with a symmetrical C/sub 2v/ planar structure. The CF3CCl2 radical was formed after γ irradiation of the CF3CCl3 (Freon) matrix. Very large long-range proton hyperfine couplings were found in radical cations of carbonyl compounds. The C8F8- ion was studied in MTHF glass, using ESR. Two new inorganic radicals, SF4- and SF4O-, were discovered

  6. Effects of corn oil and benzyl acetate on number and size of azaserine-induced foci in the pancreas of LEW and F344 rats

    Energy Technology Data Exchange (ETDEWEB)

    Longnecker, D.S.; Roebuck, B.D.; Curphey, T.J.; Lhoste, E.; Coon, C.I.; MacMillan, D.

    1986-09-01

    The response of LEW and F344 strain rats to the pancreatic carcinogen azaserine was compared using the size and number of azaserine-induced acidophilic acinar cell foci and nodules as parameters in a 4-month experiment. A second experiment compared the effect of corn oil intake by gavage and dietary routes on the growth of azaserine-induced pancreatic lesions in LEW rats. A third experiment tested the activity of benzyl acetate in regard to its ability to induce acinar cell foci or to promote the growth of such foci in azaserine-treated rats. The results showed that equivalent doses of azaserine induce two to seven times more foci in LEW than in F344 rats, and that LEW rats have a higher incidence of spontaneous foci than F344 rats. Azaserine-treated LEW rats that were given 5 mL corn oil/kg body weight 5 days per week by gavage developed more acinar cell foci than rats fed a basal diet (chow). Addition of an equivalent amount of corn oil to chow had a similar effect of enhancing the development of foci. Rats of neither strain developed acinar cell foci when benzyl acetate was given by gavage or in the diet nor was there evidence that benzyl acetate has a significant effect on the development of foci in azaserine-treated rats. These studies also demonstrate that the azaserine/rat model of pancreatic carcinogenesis which was developed in LEW rats can be adapted for use with F344 rats.

  7. RISE OF RADICALIZATION IN THE GLOBAL VILLAGE. ONLINE RADICALIZATION VS. IN-PERSON RADICALIZATION - IS THERE A DIFFERENCE?

    Directory of Open Access Journals (Sweden)

    Tanja Dramac Jiries

    2016-03-01

    Full Text Available In the vicinity of open space, some authors have called the “dark web” the perfect “breeding grounds” for generating conditions for seeds of extremism to thrive and grow. The perceived anonymity and vast information databases found here present a perfect incubator for terrorist activity. Academics and policymakers alike are as well convinced that such an open space filled with recruiter masterminds is perfectly adept at embracing the unadoptable, unconventional, or socially unfit into terrorist or jihadi organizations. Nevertheless, regardless of organizations, modernization and adoption of new technological methods in which one can obtain ideas and information, many individuals are still and to a great extent, influenced by face-to-face interactions. Intimate environments of a religious institution, somewhat of a home-like feeling in community gathering center, can equally impact a person, as can the internet and its vast informational influence. For the reason of contributing to understand the radicalization in the Global Village, this article will examine differences in online and in-person radicalization and illustrate it with some examples and attempt to make a comparison between two different exposures to information and its effects on young individuals.

  8. Isoprene, sulphoxy radical-anions and acidity

    Directory of Open Access Journals (Sweden)

    K. J. Rudziński

    2008-12-01

    Full Text Available Transformation of isoprene coupled with autoxidation of SIV in aqueous solutions was studied experimentally and by chemical-kinetic modelling over broad range of solution acidities (pH=3–9 to complement the research on aqueous-phase and heterogeneous transformation of isoprene reported recently by many laboratories. Isoprene significantly slowed down the autoxidation in acidic and basic solutions, and accelerated it slightly in neutral solutions. Simultaneously, production of sulphate ions and formation of solution acidity were significantly reduced. Formation of sulphite and sulphate derivatives of isoprene – sulphurous acid mono-(2-methyl-4-oxo-but-2-enyl ester (m/z=162.9, sulphurous acid mono-(4-hydroxy-2-methyl-but-2-enyl ester (m/z=164.9, sulphuric acid mono-(2-methyl-4-oxo-but-2-enyl ester (m/z=178.9, sulphuric acid mono-(4-hydroxy-2-methyl-but-2-enyl ester (m/z=180.9 – was indicated by mass spectroscopic analysis of post-reaction mixtures. The results of experiments were explained by changes in a subtle quantitative balance of three superimposed processes whose rates depended in different manner on the acidity of reacting solutions – the scavenging of sulphoxy radicals by isoprene, the formation of sulphoxy radicals during further reactions of isoprene radicals, and the autoxidation of SIV itself. A chemical mechanism based on this idea was explored numerically to show good agreement with experimental data. Interaction of isoprene with sulphur(IV species and oxygen can possibly result in formation of new organosulphate components of atmospheric aerosols and waters, and influence distribution of reactive sulphur and oxygen species in isoprene-emitting organisms exposed to SIV pollutants.

  9. Hydroxyl radical induced oxidation of nitrobenzene

    International Nuclear Information System (INIS)

    The hydroxylation of nitrobenzene by radiolytic techniques was examined by high-performance liquid chromatographic techniques. Owing to improvements in the method of analysis it was possible to measure phenol in air-saturated nitrobenzene solutions irradiated to low doses. The initial yields for the consumption of nitrobenzene and the formation of phenol and isomeric nitrophenols in N2O- and air-saturated systems were measured in order to establish the primary reactions of hydroxyl radicals with nitrobenzene. The initial yields for the consumption of nitrobenzene were 3.7 and 2.6 and that for total phenol were 2.3 and 2.4 in N2O- and air-saturated systems, respectively, in samples irradiated at low dose rates (0.8 krad g-1 min-1). Nearly 80 percent of the hydroxynitrocyclohexadienyl radicals disproportionate to produce isomeric nitrophenols and nitrobenzene in N2O-saturated systems without added oxidants upon irradiation at low dose rates. For a given dose the distribution of nitrophenols was dependent upon the dose rate. Observed dose rate dependence of nitrophenol production and dose rate independence of nitrobenzene consumption indicate that reactions other than disporportional and dimerization play a significant role at high dose reates. The examination of the effect of added ferricyanide ion in N2O-saturated systems showed that reliable production measurements of o- and p-nitrophenol cannot be made because of complicating secondary reactions. The initial yield for the production of m-nitrophenol was higher by a factor of greater than 3 in the presence than in the absence of ferricyanide ion. This result indicates that in the cross disproportionation reaction of m- and o- or p-hydroxynitrocyclohexadienyl radicals the meta isomer acts as an oxidizing agent and ortho and para isomers act as reducing agents. (U.S.)

  10. Rehabilitation of erectile function following radical prostatectomy

    Institute of Scientific and Technical Information of China (English)

    Andrew R. McCullough

    2008-01-01

    The concept of muscle rehabilitation after nerve injury is not a novel idea and is practiced in many branches of medicine, including urology. Bladder rehabilitation after spinal cord injury is universally practiced. The erectile dysfunction (ED) experienced after radical prostatectomy (RP) is increasingly recognized as being primarily neurogenic followed by secondary penile smooth muscle (SM) changes. There is unfortunately no standard approach to penile rehabilitation after RP because controlled prospective human studies are not available. This article reviews the epidemiology, experimental pathophysiological models, rationale for penile rehabilitation, and currently published rehabilitation strategies.

  11. Superzoom. Italia y el compromiso radical

    OpenAIRE

    Parga Prado, Marcos

    2015-01-01

    Italy: the new domestic landscape, la ambiciosa exposición que en 1972 tuvo lugar en el MoMA, supone la consagración y a la vez escenifica la muerte de lo que algunos críticos acababan de catalogar como Arquitectura Radical, término con el que intentaban unificar el trabajo de un heterogéneo y atomizado grupo de arquitectos, principalmente italianos, comprometidos con el replanteamiento total de la definición y objetivos de la disciplina. Se ponía fin así a un corto pero intenso periodo d...

  12. Synthesis of novel 6-(substituted benzyl)imidazo[2,1-b][1,3]thiazole catalyzed by polystyrene-supported palladium(II) ethylenediamine complex

    International Nuclear Information System (INIS)

    The polymer-supported palladium(II) ethylenediamine complex, [PS-en-Pd(II)], is a highly active catalyst that could be used for the Sonogashira coupling reaction between an aryl iodide and 2-amino-3-(2-propynyl)-1,3-thiazolium bromide, 3. This heterogeneous palladium catalyst is efficient, stable, and recyclable. Reaction of compound 3 with various aryl iodides, 4a-f in the presence of the [PS-en-Pd(II)] complex leads to the production of the 6-(substituted benzyl)imidazo[2,1-b][1,3]thiazoles 5a-f. (author)

  13. p-Tolyl 2-O-benzoyl-3-O-benzyl-4,6-O-benzylidene-1-thio-α-l-idopyranoside

    Directory of Open Access Journals (Sweden)

    Graeme J. Gainsford

    2010-07-01

    Full Text Available The title compound, C34H32O6S, is an ido-configured thioglycoside building block for heparan sulfate fragments. It contains disordered tolyl and O-benzyl groups with occupancy ratios of 0.539 (13:0.461 (13 and 0.613 (13:0.387 (13, respectively, as determined from a weakly diffracting crystal. The fused rings adopt chair conformations with the molecules packing into a three-dimensional network via C—H...O and three C—H...π interactions. The former interactions, occuring between molecules related by a twofold axis, define an R22(26 motif.

  14. Crystal structure of 1-benzyl-4-(2,4-dichlorophenyl-2-imino-1,2,5,6,7,8,9,10-octahydrocycloocta[b]pyridine-3-carbonitrile

    Directory of Open Access Journals (Sweden)

    R. A. Nagalakshmi

    2014-11-01

    Full Text Available In the title compound, C25H23Cl2N3, the cyclooctene ring adopts a twist chair–chair conformation. The dihedral angles between the central pyridine ring (r.m.s. deviation = 0.013 Å and the pendant chlorobenzene and benzyl rings are 78.07 (11 and 87.47 (12°, respectively. No directional interactions could be identified in the crystal and the packing is governed by van der Waals interactions.

  15. Kinetic solvent isotope effects [k(H2O)/k(D2O)] for benzyl nitrate, 4-chlorobutan-1-ol and piperidylsulphamoyl chloride

    International Nuclear Information System (INIS)

    Kinetic solvent isotope effects (KSIE = k[H2O]/k[D2O]) are reported for benzyl nitrate, 4-chlorobutan-1-ol and piperidylsulphamoyl chloride. The dependences of first-order rate constants on temperature are analysed to obtain related standard activation parameters. The significance of these parameters is discussed in relation to the mechanism of reaction. Where the solvolysis involves direct solvent participation on going from initial to transition state (e.g. an Ssub(N)2 reaction), an implicit extrathermodynamic assumption in the analysis dispenses with the information which would otherwise lead to details of the reaction mechanism. (author)

  16. Synthesis and Antimicrobial Activities of Amides of Chiral Benzyl Ethers of N-Boc Protected Aminols of L-amino acids with Succinic Acid

    International Nuclear Information System (INIS)

    The research work presented in this article describes a synthesis of chiral amides. Chiral benzyl ethers of N-Boc protected aminols reacted with succinic acid using 2,4,6-trichloro-1,3,5-triazine (TCT) as a coupling agent producing chiral amides in high yields. The synthetic amides were investigated for their antifungal and antibacterial activities against different bacterial and fungal strains. All the compounds showed excellent zone of inhibition against the three tested bacterial strains and good to moderate activity against one fungal strain. (author)

  17. Experimental and theoretical investigation of benzyl--pyrrolylketene, one- step procedure for preparing of new -lactams by [2+2] cycloaddition reaction

    Indian Academy of Sciences (India)

    Masoumeh Behzadi; Kazem Saidi; Mohammad Reza Islami; Hojatollah Khabazzadeh

    2016-01-01

    3-Phenyl-2-(1--pyrrol-1-yl) propanoic acid has been used as a ketene source in synthesizing of monocyclic-2-azetidinones. Hindrance in ketene and imines successfully controlled the diastereoselectivity of the reaction. For example, in some cases only one isomer was achieved. By using Mukaiyama reagent, the leaving group in acid was activated and the by-products were separated by simple aqueous work-up. DFT calculation indicated that the benzyl--pyrrolylketene has nonconjugated structure and the pyrrolyl ring is perpendicular to the ketene plane in both the twisted and planar structures.

  18. (E)-4-(2,5-Dimethoxy­benzyl­idene)-2-phenyl-1,3-oxazol-5(4H)-one

    OpenAIRE

    Asiri, Abdullah Mohamed; Ng, Seik Weng

    2009-01-01

    The central aza­lactone ring in the title compound, C18H15NO4, is planar (r.m.s. deviation 0.05, 0.12 Å) in both independent mol­ecules comprising the asymmetric unit. The benzyl­idene substituent is coplanar with this ring [dihedral angle between the planes = 1.8 (1)° in the first mol­ecule and 2.8 (1)° in the second], as is the phenyl substitutent [dihedral angle between rings = 4.6 (1) and 9.7 (1)°, respectively].

  19. N-Benzyl-N-methyl-3-phenyl-3-[4-(tri­fluoro­meth­yl)phen­oxy]propanamine (N-benzylflouoxetine)

    OpenAIRE

    Nosheen Kanwal; Erum Akbar Hussain; Onur Sahin

    2010-01-01

    In the title compound, C24H24F3NO, the N-benzyl derivative of fluoxetine {N-methyl-3-[4-(trifluoromethyl)phenoxy]benzenepropanamine}, the three aromatic rings A, B and C are inclined to one another by 76.77 (12)° for A/B, 17.05 (14)° for A/C and 89.66 (14)° for B/C. In the crystal structure, molecules are linked via C—H...π interactions to form one-dimensional chains propagating in the [010] direction.

  20. Investigation of the mode of binding of a novel series of N-benzyl-4-heteroaryl-1-(phenylsulfonyl)piperazine-2-carboxamides to the hepatitis C virus polymerase

    Energy Technology Data Exchange (ETDEWEB)

    Gentles, Robert G.; Sheriff, Steven; Beno, Brett R.; Wan, Changhong; Kish, Kevin; Ding, Min; Zheng, Xiaofan; Chupak, Louis; Poss, Michael A.; Witmer, Mark R.; Morin, Paul; Wang, Ying-Kai; Rigat, Karen; Lemm, Julie; Voss, Stacey; Liu, Mengping; Pelosi, Lenore; Roberts, Susan B.; Gao, Min; Kadow, John F. (BMS)

    2013-11-20

    Structure based rationales for the activities of potent N-benzyl-4-heteroaryl-1-(phenylsulfonyl)piperazine-2-carboxamide inhibitors of the hepatitis C viral polymerase are described herein. These compounds bind to the hepatitis C virus non-structural protein 5B (NS5B), and co-crystal structures of select examples from this series with NS5B are reported. Comparison of co-crystal structures of a potent analog with both NS5B genotype 1a and genotype 1b provides a possible explanation for the genotype-selectivity observed with this compound class and suggests opportunities for the further optimization of the series.

  1. A comparative study of Cu(II)-assisted vs Cu(II)-free chalcogenation on benzyl and 2°/3°-cycloalkyl moieties

    Indian Academy of Sciences (India)

    Santosh K Sahoo

    2015-12-01

    A relative synthetic strategy toward intermolecular oxidative C−Chalcogen bond formation of alkanes has been illustrated using both Cu(II) assisted Cu(II) free conditions. This led to construction of a comparative study of hydrocarbon benzylic and 2°/3°-cycloalkyl moieties bond sulfenylation and selenation protocol by the chalcogen sources, particularly sulfur and selenium, respectively. In addition, this protocol disclosed the auspicious formation of sp3C−S coupling products over leading the sp3C−N coupling products by using 2-mercaptobenzothiazole (MBT) substrates.

  2. Crystal structure of S-hexyl (E)-3-(4-methyl­benzyl­idene)di­thio­carbazate

    OpenAIRE

    M. B. H. Howlader; Begum, M. S.; Sheikh, M. C.; Miyatake, R.; E. Zangrando

    2015-01-01

    In the title compound, C15H22N2S2, the di­thio­carbazate group adopts an E conformation with respect to the C=N bond of the benzyl­idene moiety. In the crystal, mol­ecules are linked by pairs of N—H⋯S hydrogen bonds, forming inversion dimers with an R 2 2(8) ring motif. The dimers are linked via C—H⋯π inter­actions, forming chains propagating along [100].

  3. Acetyl radical generation in cigarette smoke: Quantification and simulations

    Science.gov (United States)

    Hu, Na; Green, Sarah A.

    2014-10-01

    Free radicals are present in cigarette smoke and can have a negative effect on human health. However, little is known about their formation mechanisms. Acetyl radicals were quantified in tobacco smoke and mechanisms for their generation were investigated by computer simulations. Acetyl radicals were trapped from the gas phase using 3-amino-2, 2, 5, 5-tetramethyl-proxyl (3AP) on solid support to form stable 3AP adducts for later analysis by high-performance liquid chromatography (HPLC), mass spectrometry/tandem mass spectrometry (MS-MS/MS) and liquid chromatography-mass spectrometry (LC-MS). Simulations were performed using the Master Chemical Mechanism (MCM). A range of 10-150 nmol/cigarette of acetyl radical was measured from gas phase tobacco smoke of both commercial and research cigarettes under several different smoking conditions. More radicals were detected from the puff smoking method compared to continuous flow sampling. Approximately twice as many acetyl radicals were trapped when a glass fiber particle filter (GF/F specifications) was placed before the trapping zone. Simulations showed that NO/NO2 reacts with isoprene, initiating chain reactions to produce hydroxyl radical, which abstracts hydrogen from acetaldehyde to generate acetyl radical. These mechanisms can account for the full amount of acetyl radical detected experimentally from cigarette smoke. Similar mechanisms may generate radicals in second hand smoke.

  4. Lipid radicals: Properties and detection by spin trapping

    International Nuclear Information System (INIS)

    Unsaturated lipids are rapidly oxidized to toxic products such as lipid hydroperoxides, especially when transition metals such as iron or copper are present. In a Fenton-type reaction Fe2+ converts lipid hydroperoxides to the very short-lived lipid alkoxyl radicals. The reaction was started upon the addition of Fe2+ to an aqueous linoleic acid hydroperoxide (LOOH) emulsion and the spin trap in the absence of oxygen. Even when high concentrations of spin traps were added to the incubation mixture, only secondary radical adducts were detected, probably due to the rapid rearrangement of the primary alkoxyl radicals. With the commercially available nitroso spin trap MNP we observed a slightly immobilized ESR spectrum with only one hydrogen splitting, indicating the trapping of a methinyl fragment of a lipid radical. With DMPO or 5-diethoxyphosphoryl-5-methyl-1-pyrroline N-oxide (DEPMPO) adducts were detected with carbon-centered lipid radical, with acyl radical, and with the hydroxyl radical. We also synthesized lipophilic derivatives of the spin trap DEPMPO in order to detect lipid radical species generated in the lipid phase. With all spin traps studied a lipid-derived carbon-centered radical was obtained in the anaerobic incubation system Fe2+/LOOH indicating the trapping of a lipid radical, possibly generated as a secondary reaction product of the primary lipid alkoxyl radical formed. Under aerobic conditions an SOD-insensitive oxygen-centered radical adduct was formed with DEPMPO and its lipophilic derivatives. The observed ESR parameters were similar to those of alkoxyl radical adducts, which were independently synthesized in model experiments using Fe3+-catalyzed nucleophilic addition of methanol or t-butanol to the respective spin trap. (author)

  5. Studies on protective effect of benzyl alcohol addition against radiolytic degradation of 35% TBP-n-dodecane uranyl nitrate versus 35% TBP-n-dodecane thorium nitrate- retention of U and Th

    International Nuclear Information System (INIS)

    Present study compares the effect of benzyl alcohol addition on the performance of 35% TBP-n-dodecane system subjected to radiolytic degradation in presence of nitrates of thorium and uranium. 35 %-n-dodecane solvent systems loaded with UO2(NO3)2 as well as Th(NO3)2 in the presence and absence of benzyl alcohol were subjected to steady state gamma radiolysis for absorbed dose of 6, 12 and 18 Mrad. The radiolysed samples after scrubbing with 0.01M HNO3 have been analysed for the amount of uranium and thorium separately. The amount of thorium retained by the solvent is found to be 4-5 times higher than that of uranium under identical conditions, while benzyl alcohol addition causes lowering in the retention of both the metal ions. (author)

  6. Hydrogen Radicals, Nitrogen Radicals, and the Production of Ozone in the Middle and Upper Troposphere

    Science.gov (United States)

    Bui, T. P.

    1997-01-01

    The concentrations of hydrogen radicals, OH and HO2, in the middle and upper troposphere were measured simultaneously with those of NO, O3,CO, H20, CH4, non-methane hydrocarbons, and with the ultraviolet and visible radiation field.

  7. Radical Reform Within a Liberal and Democratic Framework? Rawls and the Radical Critique of Schooling.

    Science.gov (United States)

    Claus, John F.

    1981-01-01

    The radical critique of American education portrays the schools as perpetuators of ethnic, social, and racial inequalities because they do not alter existing class relations. John Rawls' theory of social justice is discussed as an alternative approach to this situation that remains firmly grounded in the liberal tradition. (PP)

  8. Electronic paramagnetic resonance (EPR) for the study of ascorbyl radical and lipid radicals in marine organisms.

    Science.gov (United States)

    González, Paula Mariela; Aguiar, María Belén; Malanga, Gabriela; Puntarulo, Susana

    2013-08-01

    Electron paramagnetic resonance (EPR) spectroscopy detects the presence of radicals of biological interest, such as ascorbyl radical (A(•)) and lipid radicals. A(•) is easily detectable by EPR even in aqueous solution at room-temperature. Under oxidative conditions leading to changes in total ascorbate (AH(-)) content, the A(•)/AH(-) ratio could be used to estimate early oxidative stress in the hydrophilic milieu. This methodology was applied to a wide range of aquatic systems including algae, sea urchin, limpets, bivalves and fish, under physiological and oxidative stress conditions as well. The A(•)/AH(-) ratio reflected the state of one part of the oxidative defense system and provided an early and simple diagnosis of environmental stressing conditions. Oxidative damage to lipids was assessed by the EPR-sensitive adduct formation that correlates well with cell membrane damage with no interference from other biological compounds. Probe instability, tissue metabolism, and lack of spin specificity are drawback factors for employing EPR for in vivo determination of free radicals. However, the dependability of this technique, mostly by combining it with other biochemical strategies, enhances the value of these procedures as contributors to the knowledge of oxidative condition in aquatic organisms. PMID:23485428

  9. Peroxyl radical reactions with carotenoids in microemulsions: Influence of microemulsion composition and the nature of peroxyl radical precursor.

    Science.gov (United States)

    El-Agamey, Ali; McGarvey, David J

    2016-01-01

    The reactions of acetylperoxyl radicals with different carotenoids (7,7'-dihydro-β-carotene and ζ-carotene) in SDS and CTAC microemulsions of different compositions were investigated using laser flash photolysis (LFP) coupled with kinetic absorption spectroscopy. The primary objective of this study was to explore the influence of microemulsion composition and the type of surfactant used on the yields and kinetics of various transients formed from the reaction of acetylperoxyl radicals with carotenoids. Also, the influence of the site (hydrocarbon phases or aqueous phase) of generation of the peroxyl radical precursor was examined by using 4-acetyl-4-phenylpiperidine hydrochloride (APPHCl) and 1,1-diphenylacetone (11DPA) as water-soluble and lipid-soluble peroxyl radical precursors, respectively. LFP of peroxyl radical precursors with 7,7'-dihydro-β-carotene (77DH) in different microemulsions gives rise to the formation of three distinct transients namely addition radical (λmax=460 nm), near infrared transient1 (NIR, λmax=700 nm) and 7,7'-dihydro-β-carotene radical cation (77DH(•+), λmax=770 nm). In addition, for ζ-carotene (ZETA) two transients (near infrared transient1 (NIR1, λmax=660 nm) and ζ-carotene radical cation (ZETA(•+), λmax=730-740 nm)) are generated following LFP of peroxyl radical precursors in the presence of ζ-carotene (ZETA) in different microemulsions. The results show that the composition of the microemulsion strongly influences the observed yield and kinetics of the transients formed from the reactions of peroxyl radicals (acetylperoxyl radicals) with carotenoids (77DH and ZETA). Also, the type of surfactant used in the microemulsions influences the yield of the transients formed. The dependence of the transient yields and kinetics on microemulsion composition (or the type of surfactant used in the microemulsion) can be attributed to the change of the polarity of the microenvironment of the carotenoid. Furthermore, the nature of

  10. Modeling Radicalization Phenomena in Heterogeneous Populations

    CERN Document Server

    Galam, Serge

    2015-01-01

    The phenomenon of radicalization is investigated within an heterogeneous population composed of a core subpopulation, sharing a way of life locally rooted, and a recently immigrated subpopulation of different origins with ways of life which can be partly in conflict with the local one. While core agents are embedded in the country prominent culture and identity, they are not likely to modify their way of life, which make them naturally inflexible about it. On the opposite, the new comers can either decide to live peacefully with the core people adapting their way of life, or to keep strictly on their way and oppose the core population, leading eventually to criminal activities. To study the corresponding dynamics of radicalization we introduce a 3-state agent model with a proportion of inflexible agents and a proportion of flexible ones, which can be either peaceful or opponent. Assuming agents interact via weighted pairs within a Lotka-Volterra like Ordinary Differential Equation framework, the problem is an...

  11. Surface radicals in silane/hydrogen discharges

    International Nuclear Information System (INIS)

    Using threshold ionization mass spectrometry, radical densities have been measured at the substrate surface of a radio frequency discharge in silane plus hydrogen vapor. The conditions are 100-300 Pa pressure and a ratio (R) of hydrogen flow/silane flow typical of discharges used to produce large area amorphous (R=20) and microcrystalline (R=40) silicon. For comparison, we include measurements in pure-silane vapor. The neutral radicals observed in the mixed gases are H, SiH3, Si2H2, and Si2H5, with decreasing flux in that order. (Si2H4 is also seen in pure silane and SiH2 for R=20.) The H flux is sufficient for major film etching and restructuring, particularly for R=40. The ion-bombardment species were also measured, establishing that SiyHn+ (y=1-3) ion flux is much larger than the Hn+ (n=1-3) flux. The ion flux provides 15±4% of the total Si flux to the film for R=20 and 37±10% for R=40. This is larger than in pure-silane discharges, and it may be very important to film properties due to the impact energy

  12. Fast beam studies of free radical photodissociation

    Energy Technology Data Exchange (ETDEWEB)

    Cyr, D R [Lawrence Berkeley Lab., CA (United States)

    1993-11-01

    The photodissociation of free radicals is studied in order to characterize the spectroscopy and dissociation dynamics of the dissociative electronic states in these species. To accomplish this, a novel method of radical production, based on the photodetachment of the corresponding negative ion, has been combined with a highly complementary form of photofragment translational spectroscopy. The optical spectroscopy of transitions to dissociative states is determined by monitoring the total photofragment yield as a function of dissociation photon energy. Branching ratios to various product channels, internal energy distributions of the fragments, bond dissociation energies, and the translational energy-dependent photofragment recoil angular distributions are then determined at selected excitation energies. A detailed picture of the dissociation dynamics can then be formulated, allowing insight concerning the interactions of potential energy surfaces involved in the dissociation. After an introduction to the concepts and techniques mentioned above, the experimental apparatus used in these experiments is described in detail. The basis and methods used in the treatment of data, especially in the dissociation dynamics experiments, are then put forward.

  13. Hydroxyl radical induced degradation of ibuprofen

    Energy Technology Data Exchange (ETDEWEB)

    Illés, Erzsébet, E-mail: erzsebet.illes@chem.u-szeged.hu [Institute of Chemistry, Research Group of Environmental Chemistry, University of Szeged, Szeged (Hungary); Institute of Isotopes, Centre for Energy Research, Hungarian Academy of Sciences, Budapest (Hungary); Takács, Erzsébet [Institute of Isotopes, Centre for Energy Research, Hungarian Academy of Sciences, Budapest (Hungary); Dombi, András [Institute of Chemistry, Research Group of Environmental Chemistry, University of Szeged, Szeged (Hungary); Gajda-Schrantz, Krisztina [Institute of Chemistry, Research Group of Environmental Chemistry, University of Szeged, Szeged (Hungary); Department of Inorganic and Analytical Chemistry, University of Szeged, Szeged (Hungary); EMPA, Laboratory for High Performance Ceramics, Duebendorf (Switzerland); Rácz, Gergely; Gonter, Katalin; Wojnárovits, László [Institute of Isotopes, Centre for Energy Research, Hungarian Academy of Sciences, Budapest (Hungary)

    2013-03-01

    Pulse radiolysis experiments were used to characterize the intermediates formed from ibuprofen during electron beam irradiation in a solution of 0.1 mmol dm{sup −3}. For end product characterization {sup 60}Co γ-irradiation was used and the samples were evaluated either by taking their UV–vis spectra or by HPLC with UV or MS detection. The reactions of {sup ·}OH resulted in hydroxycyclohexadienyl type radical intermediates. The intermediates produced in further reactions hydroxylated the derivatives of ibuprofen as final products. The hydrated electron attacked the carboxyl group. Ibuprofen degradation is more efficient under oxidative conditions than under reductive conditions. The ecotoxicity of the solution was monitored by Daphnia magna standard microbiotest and Vibrio fischeri luminescent bacteria test. The toxic effect of the aerated ibuprofen solution first increased upon irradiation indicating a higher toxicity of the first degradation products, then decreased with increasing absorbed dose. Highlights: ► In hydroxyl radical attack on the ring mainly hydroxylated products form ► The hydrated electron attacks the carboxyl group. ► Oxidative conditions are more effective in ibuprofen decomposition than reductive. ► Ecotoxicity of ibuprofen solution first increases then decreases with irradiation.

  14. Threshold photoelectron spectroscopy of the imidogen radical

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Gustavo A., E-mail: gustavo.garcia@synchrotron-soleil.fr [Synchrotron SOLEIL, L’Orme des Merisiers, St. Aubin, BP 48, 91192 Gif sur Yvette (France); Gans, Bérenger [Institut des Sciences Moléculaires d’Orsay, Univ Paris-Sud, CNRS, Bât 210, Univ Paris-Sud, 91405 Orsay Cedex (France); Tang, Xiaofeng [Synchrotron SOLEIL, L’Orme des Merisiers, St. Aubin, BP 48, 91192 Gif sur Yvette (France); Ward, Michael; Batut, Sébastien [PC2A, Université de Lille 1, UMR CNRS-USTL 8522, Cité Scientifique Bât. C11, F-59655 Villeneuve d’Ascq (France); Nahon, Laurent [Synchrotron SOLEIL, L’Orme des Merisiers, St. Aubin, BP 48, 91192 Gif sur Yvette (France); Fittschen, Christa [PC2A, Université de Lille 1, UMR CNRS-USTL 8522, Cité Scientifique Bât. C11, F-59655 Villeneuve d’Ascq (France); Loison, Jean-Christophe [ISM, Université de Bordeaux, CNRS, 351 cours de la Libération, 33405 Talence Cedex (France)

    2015-08-15

    We present the threshold photoelectron spectroscopy of the imidogen radical (NH) recorded in the photon energy region up to 1 eV above its first ionization threshold. The radical was produced by reaction of NH{sub 3} and F in a microwave discharge flow-tube and photoionized using vacuum ultraviolet (VUV) synchrotron radiation. A double imaging coincidence spectrometer was used to record mass-selected spectra and avoid contributions from the byproducts present in the reactor and background gas. The energy region includes the ground X{sup +2}Π and first electronically excited a{sup +4}Σ{sup −} states of NH{sup +}. Strong adiabatic transitions and weak vibrational progressions up to v{sup +} = 2 are observed for both electronic states. The rotational profile seen in the origin band has been modeled using existing neutral and cationic spectroscopic constants leading to a precise determination of the adiabatic ionization energy at 13.480 ± 0.002 eV.

  15. Hegel’s Gesture Towards Radical Cosmopolitanism

    Directory of Open Access Journals (Sweden)

    Shannon Brincat

    2009-09-01

    Full Text Available This is a preliminary argument of a much larger research project inquiring into the relation betweenHegel’s philosophical system and the project of emancipation in Critical International Relations Theory. Specifically, the paper examines how Hegel’s theory of recognition gestures towards a form of radical cosmopolitanism in world politics to ensure the conditions of rational freedom for all humankind. Much of the paper is a ground-clearing exercise defining what is ‘living’ in Hegel’s thought for emancipatory approaches in world politics, to borrow from Croce’s now famous question. It focuses on Hegel’s unique concept of freedom which places recognition as central in the formation of self-consciousness and therefore as a key determinant in the conditions necessary forhuman freedom to emerge in political community. While further research is needed to ascertain the precise relationship between Hegel’s recognition theoretic, emancipation and cosmopolitanism, it is contended that the intersubjective basis of Hegel’s concept of freedom through recognition necessitates some form of radical cosmopolitanism that ensures successful processes of recognition between all peoples, the precise institutional form of which remains unspecified.

  16. EI igualitarismo radical de John Rawls

    Directory of Open Access Journals (Sweden)

    Rodríguez Zepeda, Jesús

    2004-12-01

    Full Text Available The main purpose of this paper is to offer an interpretation of the canonical statement of justice as fairness (A Theory of Justice as a deeply egalitarian, even radical, argument. In order to do so, the categories of justice as fairness strongly related to the egalitarian and distributive meaning of the rawlsian liberal model and, specifically, those aimed to solve the problem of social justice, are accurately revised, namely, the fair equality of opportunity and the difference principle. The paper evaluates the relative weight of each of these categories in the rawlsian argument for social and economic equality.

    El objetivo central de este texto es interpretar la enunciación canónica de la justicia como imparcialidad (la de Una Teoría de la Justicia como un argumento profundamente igualitarista, incluso radical. Para ello concede especial atención a las categorías de la justicia como imparcialidad que proporcionan las señas de identidad igualitaria a su modelo liberal y, en particular, a aquellas que pretenden ofrecer una solución a los problemas de la llamada justicia social como la justa igualdad de oportunidades y el principio de diferencia. El artículo evalúa el peso relativo de cada una de estas categorías en la construcción del argumento rawlsiano a favor de la igualdad social y económica.

  17. Robot-assisted radical prostatectomy: recent advances.

    Science.gov (United States)

    Mistretta, F A; Grasso, A A; Buffi, N; Cozzi, G; De Lorenzis, E; Fiori, C; Patel, V R; Porpiglia, F; Scarpa, R; Srinivas, S; Rocco, B

    2015-09-01

    Robot assisted radical prostatectomy (RARP) represents the leading application of robotic surgery in the urologic field and it has become the main treatment option for localized prostate cancer (PCa) in the USA In the present review we summarized and critically analyzed the literature of the past five years about this widely used robotic procedure. RARP has continuously evolved in terms of technical modifications and procedural steps. Long-term data are now available, suggesting comparable oncological outcomes to those of open and laparoscopic radical prostatectomy. Good functional outcomes have also been demonstrated. Technological innovations and the introduction of more advanced robotic platforms featuring novel arm-integrated equipment, together with a mature clinical experience with the robotic approach, are likely to lead towards optimal outcomes. Despite the expanding clinical implementation of RARP in the management of prostate cancer, some issues related to this procedure remain matter of debate, such as costs, comparative outcomes versus other approaches, and its role in high risk disease. PMID:26086533

  18. Fast beam studies of free radical photodissociation

    International Nuclear Information System (INIS)

    The photodissociation of free radicals is studied in order to characterize the spectroscopy and dissociation dynamics of the dissociative electronic states in these species. To accomplish this, a novel method of radical production, based on the photodetachment of the corresponding negative ion, has been combined with a highly complementary form of photofragment translational spectroscopy. The optical spectroscopy of transitions to dissociative states is determined by monitoring the total photofragment yield as a function of dissociation photon energy. Branching ratios to various product channels, internal energy distributions of the fragments, bond dissociation energies, and the translational energy-dependent photofragment recoil angular distributions are then determined at selected excitation energies. A detailed picture of the dissociation dynamics can then be formulated, allowing insight concerning the interactions of potential energy surfaces involved in the dissociation. After an introduction to the concepts and techniques mentioned above, the experimental apparatus used in these experiments is described in detail. The basis and methods used in the treatment of data, especially in the dissociation dynamics experiments, are then put forward

  19. Free Radicals and Extrinsic Skin Aging

    Directory of Open Access Journals (Sweden)

    Borut Poljšak

    2012-01-01

    Full Text Available Human skin is constantly directly exposed to the air, solar radiation, environmental pollutants, or other mechanical and chemical insults, which are capable of inducing the generation of free radicals as well as reactive oxygen species (ROS of our own metabolism. Extrinsic skin damage develops due to several factors: ionizing radiation, severe physical and psychological stress, alcohol intake, poor nutrition, overeating, environmental pollution, and exposure to UV radiation (UVR. It is estimated that among all these environmental factors, UVR contributes up to 80%. UV-induced generation of ROS in the skin develops oxidative stress, when their formation exceeds the antioxidant defence ability of the target cell. The primary mechanism by which UVR initiates molecular responses in human skin is via photochemical generation of ROS mainly formation of superoxide anion (O2−•, hydrogen peroxide (H2O2, hydroxyl radical (OH•, and singlet oxygen (1O2. The only protection of our skin is in its endogenous protection (melanin and enzymatic antioxidants and antioxidants we consume from the food (vitamin A, C, E, etc.. The most important strategy to reduce the risk of sun UVR damage is to avoid the sun exposure and the use of sunscreens. The next step is the use of exogenous antioxidants orally or by topical application and interventions in preventing oxidative stress and in enhanced DNA repair.

  20. Free radical facilitated damage of ungual keratin.

    Science.gov (United States)

    Khengar, Rajeshree H; Brown, Marc B; Turner, Rob B; Traynor, Matthew J; Holt, Katherine B; Jones, Stuart A

    2010-09-01

    Thioglycolic acid (TA) and urea hydrogen peroxide (urea H(2)O(2)) are thought to disrupt alpha-keratin disulfide links in the nail. However, optimal clinical use of these agents to improve the treatment of nail disorders is currently hindered by a lack of fundamental data to support their mechanism of action. The aim of this study was to investigate how the redox environment of ungual keratin, when manipulated by TA and urea H(2)O(2), influenced the properties of the nail barrier. Potentiometric and voltammetric measurements demonstrated that urea H(2)O(2) obeyed the Nernst equation for a proton coupled one-electron transfer redox process while TA underwent a series of redox reactions that was complicated by electrode adsorption and dimer formation. The functional studies demonstrated that nail permeability, measured through TBF penetration (38.51+/-10.94 microg/cm(2)/h) and nail swelling (244.10+/-14.99% weight increase), was greatest when relatively low concentrations of the thiolate ion were present in the applied solution. Limiting the thiolate ion to low levels in the solution retards thiolate dimerisation and generates thiyl free radicals. It appeared that this free radical generation was fundamental in facilitating the redox-mediated keratin disruption of the ungual membrane. PMID:20550963

  1. Hydroxyl radical induced degradation of ibuprofen

    International Nuclear Information System (INIS)

    Pulse radiolysis experiments were used to characterize the intermediates formed from ibuprofen during electron beam irradiation in a solution of 0.1 mmol dm−3. For end product characterization 60Co γ-irradiation was used and the samples were evaluated either by taking their UV–vis spectra or by HPLC with UV or MS detection. The reactions of ·OH resulted in hydroxycyclohexadienyl type radical intermediates. The intermediates produced in further reactions hydroxylated the derivatives of ibuprofen as final products. The hydrated electron attacked the carboxyl group. Ibuprofen degradation is more efficient under oxidative conditions than under reductive conditions. The ecotoxicity of the solution was monitored by Daphnia magna standard microbiotest and Vibrio fischeri luminescent bacteria test. The toxic effect of the aerated ibuprofen solution first increased upon irradiation indicating a higher toxicity of the first degradation products, then decreased with increasing absorbed dose. Highlights: ► In hydroxyl radical attack on the ring mainly hydroxylated products form ► The hydrated electron attacks the carboxyl group. ► Oxidative conditions are more effective in ibuprofen decomposition than reductive. ► Ecotoxicity of ibuprofen solution first increases then decreases with irradiation

  2. Analysis of radicals, radical precursors and chemical transformations for Houston/Texas

    Science.gov (United States)

    Rappenglück, Bernhard; Czader, Beata; Li, Xiangshang

    2015-04-01

    Air quality simulations were performed for the Houston-Galveston-Brazoria area for springtime conditions in May and June of 2009. Meteorological parameters predicted by Weather Research and Forecasting (WRF) model, for which data assimilation with recursive objective analysis was performed, are well simulated most of the time. The Community Multiscale Air Quality (CMAQ) model driven by meteorology from WRF simulates ozone and many other trace species, including radical precursors such as HCHO and HONO, with a satisfactory agreement with observations. While CMAQ satisfactorily captures the daily variations of the OH radical, it sometimes underestimates its high daytime values. Concentrations of HO2 are often underpredicted in polluted air masses and persistently severely underpredicted at low NOx conditions, when the Houston air is affected bymarine air masses. In contrast, concentrations of H2O2 and CH3OOHare almost always overpredicted by the model, the overprediction occurs frequently in the polluted air and occurs always when marine air is encountered. Those mispredictions are consistent despite day-to-day variations in meteorological conditions and emissions and bring into question current representation of radical-related chemistry in the model as radical production and recirculation in the model is overtaken by termination processes and creation ofmore stable compounds, such asH2O2 and CH3OOH. Smaller model biases of H2O2 and peroxides are associated with lower humidity. The relative importance of various photolysis processes as radical sources in the Houston atmosphere was also elucidated. Morning HOx formation is dominated by HONO while ozone contributes the most during midday. HONO contribution to HOx formation is more pronounced at the surface layer where most of it is formed, radical production from ozone is more important at elevated levels where higher concentrations of ozone are observed. Formaldehyde contributes up to 40% and also peaks during midday

  3. Radicals of DNA and DNA nucleotides generated by ionising radiation

    International Nuclear Information System (INIS)

    A first stage of cell processes leading to DNA damage of initiated by radical reactions. In a model system such transformations were generated by ionising radiation which involves production of electron loss and electron gain centers of the substrate and radical formation. Using cryogenic ESR spectroscopy it was found that the DNA nucleotides, which convert to radical anions upon electron capture undergo the separation of unpaired spin and charge due to protonation. Circular and linear dichroism studies enabled to conclude that iron ions(III) induce strong changes in the DNA helical structure indicating their coordination with nitrogen bases. The repair of DNA radicals produced via radiolytic oxidation, i.e. the guanine radical cation and the allyl type radical of thymine, is possible at elevated temperatures due to the involvement of sulphydryl groups. The influence of the thiol charge is then limited

  4. Spin polarization transfer by the radical pair mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Zarea, Mehdi, E-mail: m-zarea@northwestern.edu; Ratner, Mark A.; Wasielewski, Michael R. [Department of Chemistry and Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113 (United States)

    2015-08-07

    In a three-site representation, we study a spin polarization transfer from radical pair spins to a nearby electron or nuclear spin. The quantum dynamics of the radical pair spins is governed by a constant exchange interaction between the radical pair spins which have different Zeeman frequencies. Radical pair spins can recombine to the singlet ground state or to lower energy triplet states. It is then shown that the coherent dynamics of the radical pair induces spin polarization on the nearby third spin in the presence of a magnetic field. The spin polarization transfer depends on the difference between Zeeman frequencies, the singlet and triplet recombination rates, and on the exchange and dipole-dipole interactions between the different spins. In particular, the sign of the polarization depends on the exchange coupling between radical pair spins and also on the difference between singlet and triplet recombination rate constants.

  5. Radiogenic free radicals as molecular probes in bone

    International Nuclear Information System (INIS)

    Exposure of bone mineral to X-rays generates free radicals. These are usually very labile, but can be stabilized at liquid nitrogen temperatures for study by electron spin resonance spectroscopy. The free radicals thus detected in the present study included one with resonances arising from an electron excess center and 2 species with electron-deficit centers: a phosphate anion radical and a radical associated with carbonate. Each of these radicals seemed to be located chiefly at the mineral surface and was sensitive to the surface environment. Presence of an organic phase, as in whole bone, modified free radical production in a manner that suggests interference with the formation of electron deficit centers. Comparison with other synthetic minerals suggests that precipitated carbonate-apatites are good models for bone mineral. (orig.)

  6. Oxygen radicals stimulate guinea pig gallbladder glycoprotein secretion in vitro

    International Nuclear Information System (INIS)

    In several animal models of cholelithiasis, and in humans with gallstones, hypersecretion of gallbladder mucin is observed. This study was undertaken to determine the effect of oxygen radicals on guinea pig gallbladder glycoprotein secretion in organ culture. Mucosal explants were incubated with [3H]glucosamine hydrochloride to label glycoproteins, then exposed to oxygen radicals generated by chelated ferric iron and ascorbic acid. Marked stimulation of glycoprotein release was observed after a 30-min exposure to the oxygen radical-generating system, and the effect was inhibited by mannitol. The stimulatory effect of hydroxyl radical was not accompanied by leakage of intracellular lactate dehydrogenase. Parallel experiments with human granulocytes activated with f-Met-Leu-Phe and coincubated with gallbladder explants revealed similar results. These results indicate that oxygen radicals, especially the hydroxyl radical (OH), are capable of stimulating rapid release of mucous-type glycoproteins from gallbladder epithelium

  7. Spin polarization transfer by the radical pair mechanism

    International Nuclear Information System (INIS)

    In a three-site representation, we study a spin polarization transfer from radical pair spins to a nearby electron or nuclear spin. The quantum dynamics of the radical pair spins is governed by a constant exchange interaction between the radical pair spins which have different Zeeman frequencies. Radical pair spins can recombine to the singlet ground state or to lower energy triplet states. It is then shown that the coherent dynamics of the radical pair induces spin polarization on the nearby third spin in the presence of a magnetic field. The spin polarization transfer depends on the difference between Zeeman frequencies, the singlet and triplet recombination rates, and on the exchange and dipole-dipole interactions between the different spins. In particular, the sign of the polarization depends on the exchange coupling between radical pair spins and also on the difference between singlet and triplet recombination rate constants

  8. Measurements of hydroxyl and hydroperoxy radicals during CalNex-LA: Model comparisons and radical budgets

    Science.gov (United States)

    Griffith, S. M.; Hansen, R. F.; Dusanter, S.; Michoud, V.; Gilman, J. B.; Kuster, W. C.; Veres, P. R.; Graus, M.; Gouw, J. A.; Roberts, J.; Young, C.; Washenfelder, R.; Brown, S. S.; Thalman, R.; Waxman, E.; Volkamer, R.; Tsai, C.; Stutz, J.; Flynn, J. H.; Grossberg, N.; Lefer, B.; Alvarez, S. L.; Rappenglueck, B.; Mielke, L. H.; Osthoff, H. D.; Stevens, P. S.

    2016-04-01

    Measurements of hydroxyl (OH) and hydroperoxy (HO2*) radical concentrations were made at the Pasadena ground site during the CalNex-LA 2010 campaign using the laser-induced fluorescence-fluorescence assay by gas expansion technique. The measured concentrations of OH and HO2* exhibited a distinct weekend effect, with higher radical concentrations observed on the weekends corresponding to lower levels of nitrogen oxides (NOx). The radical measurements were compared to results from a zero-dimensional model using the Regional Atmospheric Chemical Mechanism-2 constrained by NOx and other measured trace gases. The chemical model overpredicted measured OH concentrations during the weekends by a factor of approximately 1.4 ± 0.3 (1σ), but the agreement was better during the weekdays (ratio of 1.0 ± 0.2). Model predicted HO2* concentrations underpredicted by a factor of 1.3 ± 0.2 on the weekends, while measured weekday concentrations were underpredicted by a factor of 3.0 ± 0.5. However, increasing the modeled OH reactivity to match the measured total OH reactivity improved the overall agreement for both OH and HO2* on all days. A radical budget analysis suggests that photolysis of carbonyls and formaldehyde together accounted for approximately 40% of radical initiation with photolysis of nitrous acid accounting for 30% at the measurement height and ozone photolysis contributing less than 20%. An analysis of the ozone production sensitivity reveals that during the week, ozone production was limited by volatile organic compounds throughout the day during the campaign but NOx limited during the afternoon on the weekends.

  9. Critical role of p53 upregulated modulator of apoptosis in benzyl isothiocyanate-induced apoptotic cell death.

    Directory of Open Access Journals (Sweden)

    Marie Lue Antony

    Full Text Available Benzyl isothiocyanate (BITC, a constituent of edible cruciferous vegetables, decreases viability of cancer cells by causing apoptosis but the mechanism of cell death is not fully understood. The present study was undertaken to determine the role of Bcl-2 family proteins in BITC-induced apoptosis using MDA-MB-231 (breast, MCF-7 (breast, and HCT-116 (colon human cancer cells. The B-cell lymphoma 2 interacting mediator of cell death (Bim protein was dispensable for proapoptotic response to BITC in MCF-7 and MDA-MB-231 cells as judged by RNA interference studies. Instead, the BITC-treated MCF-7 and MDA-MB-231 cells exhibited upregulation of p53 upregulated modulator of apoptosis (PUMA protein. The BITC-mediated induction of PUMA was relatively more pronounced in MCF-7 cells due to the presence of wild-type p53 compared with MDA-MB-231 with mutant p53. The BITC-induced apoptosis was partially but significantly attenuated by RNA interference of PUMA in MCF-7 cells. The PUMA knockout variant of HCT-116 cells exhibited significant resistance towards BITC-induced apoptosis compared with wild-type HCT-116 cells. Attenuation of BITC-induced apoptosis in PUMA knockout HCT-116 cells was accompanied by enhanced G2/M phase cell cycle arrest due to induction of p21 and down regulation of cyclin-dependent kinase 1 protein. The BITC treatment caused a decrease in protein levels of Bcl-xL (MCF-7 and MDA-MB-231 cells and Bcl-2 (MCF-7 cells. Ectopic expression of Bcl-xL in MCF-7 and MDA-MB-231 cells and that of Bcl-2 in MCF-7 cells conferred protection against proapoptotic response to BITC. Interestingly, the BITC-treated MDA-MB-231 cells exhibited induction of Bcl-2 protein expression, and RNA interference of Bcl-2 in this cell line resulted in augmentation of BITC-induced apoptosis. The BITC-mediated inhibition of MDA-MB-231 xenograft growth in vivo was associated with the induction of PUMA protein in the tumor. In conclusion, the results of the present study

  10. Benzyl isothiocyanate alters the gene expression with cell cycle regulation and cell death in human brain glioblastoma GBM 8401 cells.

    Science.gov (United States)

    Tang, Nou-Ying; Chueh, Fu-Shin; Yu, Chien-Chih; Liao, Ching-Lung; Lin, Jen-Jyh; Hsia, Te-Chun; Wu, King-Chuen; Liu, Hsin-Chung; Lu, Kung-Wen; Chung, Jing-Gung

    2016-04-01

    Glioblastoma multiforme (GBM) is a highly malignant devastating brain tumor in adults. Benzyl isothiocyanate (BITC) is one of the isothiocyanates that have been shown to induce human cancer cell apoptosis and cell cycle arrest. Herein, the effect of BITC on cell viability and apoptotic cell death and the genetic levels of human brain glioblastoma GBM 8401 cells in vitro were investigated. We found that BITC induced cell morphological changes, decreased cell viability and the induction of cell apoptosis in GBM 8401 cells was time-dependent. cDNA microarray was used to examine the effects of BITC on GBM 8401 cells and we found that numerous genes associated with cell death and cell cycle regulation in GBM 8401 cells were altered after BITC treatment. The results show that expression of 317 genes was upregulated, and two genes were associated with DNA damage, the DNA-damage-inducible transcript 3 (DDIT3) was increased 3.66-fold and the growth arrest and DNA-damage-inducible α (GADD45A) was increased 2.34-fold. We also found that expression of 182 genes was downregulated and two genes were associated with receptor for cell responses to stimuli, the EGF containing fibulin-like extracellular matrix protein 1 (EFEMP1) was inhibited 2.01-fold and the TNF receptor-associated protein 1 (TRAP1) was inhibited 2.08-fold. BITC inhibited seven mitochondria ribosomal genes, the mitochondrial ribosomal protein; tumor protein D52 (MRPS28) was inhibited 2.06-fold, the mitochondria ribosomal protein S2 (MRPS2) decreased 2.07-fold, the mitochondria ribosomal protein L23 (MRPL23) decreased 2.08-fold, the mitochondria ribosomal protein S2 (MRPS2) decreased 2.07-fold, the mitochondria ribosomal protein S12 (MRPS12) decreased 2.08-fold, the mitochondria ribosomal protein L12 (MRPL12) decreased 2.25-fold and the mitochondria ribosomal protein S34 (MRPS34) was decreased 2.30-fold in GBM 8401 cells. These changes of gene expression can provide the effects of BITC on the

  11. Inactivation of biologically active DNA by isopropanol and formate radicals

    International Nuclear Information System (INIS)

    If OH and H radicals, produced by absorption of ionizing radiation in aqueous solutions, are scavenged with isopropanol or sodium formate, secondary radicals are formed which can inactivate phiX174 DNA. From experiments at various DNA concentrations and dose rates we were able to determine the rate constant and the inactivation efficiency of the reaction of these organic radicals with single stranded DNA. (author)

  12. Fluoropolymer materials and architectures prepared by controlled radical polymerizations

    DEFF Research Database (Denmark)

    Hansen, Natanya Majbritt Louie; Jankova Atanasova, Katja; Hvilsted, Søren

    2007-01-01

    This review initially summarizes the mechanisms, merits and limitations of the three controlled radical polymerizations: nitroxide mediated polymerization (NMP), atom transfer radical polymerization (ATRP) or metal catalyzed living radical polymerization, and reversible addition–fragmentation chain...... transfer (RAFT) polymerization. This is followed by two parts, one dealing with homo- and copolymerizations of fluorinated methacrylates and acrylates, and a second where fluorinated styrenes, alone or in combination with other monomers, are the main issues. In these parts, initiators (including...

  13. Free Radical Scavenging and Cellular Antioxidant Properties of Astaxanthin

    OpenAIRE

    Janina Dose; Seiichi Matsugo; Haruka Yokokawa; Yutaro Koshida; Shigetoshi Okazaki; Ulrike Seidel; Manfred Eggersdorfer; Gerald Rimbach; Tuba Esatbeyoglu

    2016-01-01

    Astaxanthin is a coloring agent which is used as a feed additive in aquaculture nutrition. Recently, potential health benefits of astaxanthin have been discussed which may be partly related to its free radical scavenging and antioxidant properties. Our electron spin resonance (ESR) and spin trapping data suggest that synthetic astaxanthin is a potent free radical scavenger in terms of diphenylpicryl-hydrazyl (DPPH) and galvinoxyl free radicals. Furthermore, astaxanthin dose-dependently quench...

  14. Generation and propagation of radical reactions on proteins

    DEFF Research Database (Denmark)

    Hawkins, C L; Davies, Michael Jonathan

    2001-01-01

    The oxidation of proteins by free radicals is thought to play a major role in many oxidative processes within cells and is implicated in a number of human diseases as well as ageing. This review summarises information on the formation of radicals on peptides and proteins and how radical damage may...... final section of this review examines the control of protein oxidation and how such damage might be limited by antioxidants....

  15. [Radicalism and feminism: The case of Poulain de la Barre].

    Science.gov (United States)

    Pellegrin, Marie-Frédérique

    2015-12-01

    Early modern radicalism and its criteria are described and defined by Jonathan Israel in various works. Poulain de la Barre, one of the first modern feminist thinkers, first is used by Israel as an example of the so-called radical Enlightenment and finally is rejected as such. This case study exhibed the necessity of questionning the coherence of the required criteria for defining a « radical » thinker, especially when examinating carefully the last paragraph of Spinoza's Political Treatise. PMID:26746644

  16. Positive Effect of Propolis on Free Radicals in Burn Wounds

    OpenAIRE

    Pawel Olczyk; Pawel Ramos; Katarzyna Komosinska-Vassev; Jerzy Stojko; Barbara Pilawa

    2013-01-01

    Concentration and properties of free radicals in the burn wounds treated with propolis were examined by the use of electron paramagnetic resonance spectroscopy. Magnetic spin-spin interactions and complex free radicals structures in wound beds were studied. The results were compared to those obtained for silver sulphadiazine used as a standard pharmaceutical agent. The changes of free radicals in the matrix of injury with time of exposition on these substances were tested. The aim of this stu...

  17. Free radical-mediated activation of hydrazine derivatives.

    OpenAIRE

    Kalyanaraman, B.; Sinha, B. K.

    1985-01-01

    Hydrazines are known to undergo oxidative activation in several enzymatic systems in vitro. Free radicals or carbonium ions have been proposed as active intermediates during such activation. The toxic effects elicited by hydrazines have also been linked to free radical-mediated activation. In this report, we have reviewed the identification of organic free radicals from hydrazines by direct ESR and ESR-spin trapping.

  18. In vivo detection of radicals in biological reactions.

    OpenAIRE

    Chance, B; G. Gao

    1994-01-01

    In vivo detection of free radicals on a quantitative basis is essential for an establishment of their role in membrane, protein, and cell and tissue damage. This article compares optical methods, including chemiluminescence, electron paramagnetic resonance (EPR) and NMR methods for the study of free radicals and free radical damage, especially reperfusion injury neutrophil accumulation 6 hr after the ischemia/reperfusion insult. The chemiluminescence method is applied to an evaluation of the ...

  19. Administration of 4-(α-L-Rhamnosyloxy)-benzyl Isothiocyanate Delays Disease Phenotype in SOD1G93A Rats: A Transgenic Model of Amyotrophic Lateral Sclerosis

    Science.gov (United States)

    De Nicola, Gina Rosalinda; Mazzon, Emanuela

    2015-01-01

    4-(α-L-Rhamnosyloxy)-benzyl glucosinolate (glucomoringin, GMG) is a compound found in Moringa oleifera seeds. Myrosinase-catalyzed hydrolysis at neutral pH of GMG releases the biologically active compound 4-(α-L-rhamnosyloxy)-benzyl isothiocyanate (GMG-ITC). The present study was designed to test the potential therapeutic effectiveness of GMG-ITC to counteract the amyotrophic lateral sclerosis (ALS) using SOD1tg rats, which physiologically develops SOD1G93A at about 16 weeks of life, and can be considered a genetic model of disease. Rats were treated once a day with GMG (10 mg/Kg) bioactivated with myrosinase (20 µL/rat) via intraperitoneal (i.p.) injection for two weeks before disease onset and the treatment was prolonged for further two weeks before the sacrifice. Immune-inflammatory markers as well as apoptotic pathway were investigated to establish whether GMG-ITC could represent a new promising tool in clinical practice to prevent ALS. Achieved data display clear differences in molecular and biological profiles between treated and untreated SOD1tg rats leading to guessing that GMG-ITC can interfere with the pathophysiological mechanisms at the basis of ALS development. Therefore, GMG-ITC produced from myrosinase-catalyzed hydrolysis of pure GMG could be a candidate for further studies aimed to assess its possible use in clinical practice for the prevention or to slow down this disease. PMID:26075221

  20. Mg-AI Mixed Oxides Supported Bimetallic Au-Pd Nanoparticles with Superior Catalytic Properties in Aerobic Oxidation of Benzyl Alcohol and Glycerol

    Institute of Scientific and Technical Information of China (English)

    王亮; 张伟; 曾尚景; 苏党生; 孟祥举; 肖丰收

    2012-01-01

    Nano-sized Au and Pd catalysts are favorable for oxidations with molecular oxygen, and the preparation of this kind of nanoparticles with high catalytic activities is strongly desirable. We report a successful synthesis of bimetal- lic Au-Pd nanoparticles with rich edge and comer sites on unique support of Mg-AI mixed oxides (Au-Pd/MAO), which are favorable for producing metal nanoparticles with high degree of coordinative unsaturation of metal atoms The systematic microscopic characterizations confirm the bimetallic Au-Pd nanoparticles are present as Au-Pd alloy The irregular shape of the bimetallic nanoparticles are directly observed in HRTEM images. As we expected, Au-Pd/MAO gives very excellent catalytic performances in the aerobic oxidation of benzyl alcohol and glycerol. For example, Au-Pd/MAO shows very high TOF of 91000 h i at 433 K with molecular oxygen at air pressure in solvent-free oxidation of benzyl alcohol; this catalyst also shows relatively high selectivity for tartronic acid (TA- RAC, 36.6%) at high conversion (98.5%) in aerobic oxidation of glycerol. The superior catalytic properties of Au-Pd/MAO would be potentially important tbr production of fine chemicals.

  1. Administration of 4-(α-L-rhamnosyloxy)-benzyl isothiocyanate delays disease phenotype in SOD1(G93A) rats: a transgenic model of amyotrophic lateral sclerosis.

    Science.gov (United States)

    Galuppo, Maria; Giacoppo, Sabrina; Iori, Renato; De Nicola, Gina Rosalinda; Bramanti, Placido; Mazzon, Emanuela

    2015-01-01

    4-(α-L-Rhamnosyloxy)-benzyl glucosinolate (glucomoringin, GMG) is a compound found in Moringa oleifera seeds. Myrosinase-catalyzed hydrolysis at neutral pH of GMG releases the biologically active compound 4-(α-L-rhamnosyloxy)-benzyl isothiocyanate (GMG-ITC). The present study was designed to test the potential therapeutic effectiveness of GMG-ITC to counteract the amyotrophic lateral sclerosis (ALS) using SOD1tg rats, which physiologically develops SOD1(G93A) at about 16 weeks of life, and can be considered a genetic model of disease. Rats were treated once a day with GMG (10 mg/Kg) bioactivated with myrosinase (20 µL/rat) via intraperitoneal (i.p.) injection for two weeks before disease onset and the treatment was prolonged for further two weeks before the sacrifice. Immune-inflammatory markers as well as apoptotic pathway were investigated to establish whether GMG-ITC could represent a new promising tool in clinical practice to prevent ALS. Achieved data display clear differences in molecular and biological profiles between treated and untreated SOD1tg rats leading to guessing that GMG-ITC can interfere with the pathophysiological mechanisms at the basis of ALS development. Therefore, GMG-ITC produced from myrosinase-catalyzed hydrolysis of pure GMG could be a candidate for further studies aimed to assess its possible use in clinical practice for the prevention or to slow down this disease. PMID:26075221

  2. Synthesis and Evaluation of Optical 2-Benzyl-5-bromo-4- oxopentanoic Acids as Transition-state Analog Inhibitors against Carboxypeptidase A

    Institute of Scientific and Technical Information of China (English)

    JIN,Jing-Yi; WANG,Shou-Feng; XUAN,Wei; SHENG,Ji-Wen; WANG,Si-Hong; TIAN,Guan-Rong

    2008-01-01

    Both enantiomers of 2-benzyl-5-bromo-4-oxopentanoic acid were prepared utilizing the diazo ketones as the key intermediates. The compounds were assayed for inhibitory activity against carboxypeptidase A (CPA, EC 3.4.17.1). The (R)-form is 260-fold more potent than the corresponding (S)-form. The finding that (R)-form, which belongs to the L-series, is mostly responsible for the inhibitory activity accords with the substrate specificity of CPA.For comparison, both the optical forms of 2-benzyl-4-oxopentanoic acid were also synthesized and evaluated as the inhibitors against CPA. These results reveal that the introduction of a bromo group at the α-position of ketones can significantly enhance the electrophilicity of the carbonyl group. Further molecular docking study suggested that the gem-diol form of the α-bromo ketone, which mimics the transition state in the CPA catalytic process, could chelate the zinc ion in the active site of CPA and thus result in the strong inhibition.

  3. Benzyl and Methyl Fatty Hydroxamic Acids Based on Palm Kernel Oil as Chelating Agent for Liquid-Liquid Iron(III Extraction

    Directory of Open Access Journals (Sweden)

    Jamileh Amin

    2012-02-01

    Full Text Available Liquid-liquid iron(III extraction was investigated using benzyl fatty hydroxamic acids (BFHAs and methyl fatty hydroxamic acids (MFHAs as chelating agents through the formation of iron(III methyl fatty hydroxamate (Fe-MFHs or iron(III benzyl fatty hydroxamate (Fe-BFHs in the organic phase. The results obtained under optimized conditions, showed that the chelating agents in hexane extract iron(III at pH 1.9 were realized effectively with a high percentage of extraction (97.2% and 98.1% for MFHAs and BFHAs, respectively. The presence of a large amount of Mg(II, Ni(II, Al(III, Mn(II and Co(II ions did affect the iron(III extraction. Finally stripping studies for recovering iron(III from organic phase (Fe-MFHs or Fe-BFHs dissolved in hexane were carried out at various concentrations of HCl, HNO3 and H2SO4. The results showed that the desired acid for recovery of iron(III was 5 M HCl and quantitative recovery of iron(III was achieved from Fe(III-MFHs and Fe(III-BFHs solutions in hexane containing 5 mg/L of Fe(III.

  4. Macrocyclic Se4N2[7,7]ferrocenophane and Se2N[10]ferrocenophane containing benzyl unit: synthesis, complexation, crystal structures, electrochemical and optical properties.

    Science.gov (United States)

    Qu, Jian; Song, Yinglin; Ji, Wei; Jing, Su; Zhu, Dunru; Huang, Wei; Zheng, Mengxi; Li, Yanle; Ma, Jing

    2016-02-28

    Two novel macrocyclic polyselena[n]ferrocenophanes containing a pendent benzyl unit, 20-membered Se4N2[7,7]ferrocenophane (L1) and 10-membered Se2N[10]ferrocenophane (L2), were designed and synthesized. The reaction of L1 with two molar amounts of metal salts (M = Cu(+), Cu(2+), Pd(2+) and Hg(2+)) led to six dimetallic complexes 1-6. A crystallographic study revealed that each metal center in 1-5 was tetracoordinated to two selenium atoms from different ferrocene units, one aliphatic nitrogen atom and one co-ligand. The structures of the complexes contain a two-fold axis perpendicular to the molecular plane with two pendant benzyl moieties in an anti-conformation. Macrocycle L1 gives significant electrochemical, linear and third-order nonlinear optical responses to Cu(2+) and Hg(2+). The DFT/B3LYP calculations of 4 demonstrated a small HOMO-LUMO energy gap and delocalization of the π-electron cloud in the frontier molecular orbitals, which led to the enhancement of molecular NLO properties after complexation. The results show that the oxidation state of the ferrocene unit is accompanied by significant differences in the corresponding absorption spectra and third-order NLO properties. PMID:26790582

  5. Effects of ethyl and benzyl groups on the miscibility and properties of castor oil-based polyurethane/starch derivative semi-interpenetrating polymer networks.

    Science.gov (United States)

    Cao, Xiaodong; Wang, Yixiang; Zhang, Lina

    2005-09-16

    Cornstarch derivative (ES), prepared using diethyl sulfate as an etherifying reagent, was blended with castor oil-based polyurethane (PU) prepolymer to obtain a series of semi-interpenetrating polymer network (semi-IPN) materials, named as UES films. Simultaneously, other kinds of semi-IPN (UBS2) were prepared from PU and benzyl starch (BS2) to compare the effects of the substitute groups. The differences in the miscibility and properties of the two series of materials were investigated using attenuated total reflection Fourier transform infrared spectroscopy, atomic force microscopy, dynamic mechanical thermal analysis, ultraviolet-visible spectroscopy, water-sensitivity and tensile testing. The experimental results revealed that UBS2 films exhibit stronger interfacial attraction and better phase mixing than the UES films, as a result of specific interactions between the PU hard segments and BS2 phenyl groups. The optical transmittance, water-resistivity, tensile strength, and elongation at break of the UBS2 films were clearly higher than those of the UES films containing the same concentration of PU. In particular, the miscibility and properties of the UES film with 40 wt.-% ES, were very poor, whereas the semi-IPN films containing 70 wt.-% benzyl starch still had a certain miscibility and good properties. Therefore, the phenyl groups play an important role in the improvement of the miscibility and properties of the semi-IPN materials. PMID:16143996

  6. Weak intramolecular and intermolecular hydrogen bonding of benzyl alcohol, 2-phenylethanol and 2-phenylethylamine in the adsorption on graphitized thermal carbon black.

    Science.gov (United States)

    Varfolomeeva, V V; Terentev, A V

    2015-10-01

    The paper discusses the role of weak intra- and intermolecular hydrogen bonds in the adsorption of benzyl alcohol, 2-phenylethanol and 2-phenylethylamine on graphitized thermal carbon black (GTCB). Using the B3LYP/aug-cc-pVDZ, B3LYP/aug-cc-pVTZ methods and the molecular-statistical theory of adsorption we found the structural and energetic parameters of the conformers to be stable in the gas phase and in the adsorbed state. The contribution of weak OHπ, NHπ, CHO hydrogen bonds to the stabilization of the conformers was defined by the method of non-covalent interactions (NCI). Based on the difference in the experimental and calculated values of the Henry constant Δ ln K1 calculation of the thermodynamic characteristics of adsorption (TCA) has been shown. To obtain a high predictive power of molecular-statistical calculation it was necessary to take due account of the structural features of flexible molecules in the adsorbed state. A significant impact of the weak OHπGTCB intermolecular hydrogen bond of benzyl alcohol on the TCA values has been established. PMID:26327209

  7. A simple spectrophotometric method for the determination of trace levels of molybdenum using N,N‧-bis(2-hydroxy-5-bromo-benzyl)1,2 diaminopropane

    Science.gov (United States)

    Kara, Derya; Karadaş, Cennet

    2015-08-01

    The present work describes a selective, rapid and economical spectrophotometric method for the determination of molybdenum using N,N‧-bis(2-hydroxy-5-bromo-benzyl)1,2 diaminopropane. Molybdenum(VI) reacts with N,N‧-bis(2-hydroxy-5-bromo-benzyl)1,2 diaminopropane to form a stable 1:1 yellow complex with an absorption maximum at 342 nm. The reaction is completed within 10 min and the absorbance of the molybdenum complex remains stable for at least 1 week at room temperature. The effective molar absorption coefficient at 342 nm was 9.6 × 103 L mol-1 cm-1. Under optimal conditions, the complex obeys Beer's law from 0 to 9.9 μg mL-1. The relative standard deviation was 0.08% (for 11 samples, each containing 6 μg mL-1 molybdenum). Under the optimum conditions, the detection limit (3σ) was 17.7 μg L-1 for molybdenum without any preconcentration. The precision was determined from 30 results obtained for 4.80 μg mL-1 Mo(VI); the mean value of a molybdenum(VI) was 4.83 μg ml-1 with a standard derivation of 0.002 μg ml-1 molybdenum(VI).

  8. Synthesis and Insecticidal Activity of Spinosyns with C9-O-Benzyl Bioisosteres in Place of the 2',3',4'-Tri-O-methyl Rhamnose.

    Science.gov (United States)

    Oliver, M Paige; Crouse, Gary D; Demeter, David A; Sparks, Thomas C

    2015-06-17

    The spinosyns are fermentation-derived natural products active against a wide range of insect pests. They are structurally complex, consisting of two sugars (forosamine and rhamnose) coupled to a macrocyclic tetracycle. Removal of the rhamnose sugar results in a >100-fold reduction in insecticidal activity. C9-O-benzyl analogues of spinosyn D were synthesized to determine if the 2',3',4'-tri-O-methyl rhamnose moiety could be replaced with a simpler, synthetic bioisostere. Insecticidal activity was evaluated against larvae of Spodoptera exigua (beet armyworm) and Helicoverpa zea (corn earworm). Whereas most analogues were far less active than spinosyn D, a few of the C9-O-benzyl analogues, such as 4-CN, 4-Cl, 2-isopropyl, and 3,5-diOMe, were within 3-15 times the activity of spinosyn D for larvae of S. exigua and H. zea. Thus, although not yet quite as effective, synthetic bioisosteres can substitute for the naturally occurring 2',3',4'-tri-O-methyl rhamnose moiety. PMID:25993441

  9. Bithiophene radical cation: Resonance Raman spectroscopy and molecular orbital calculations

    DEFF Research Database (Denmark)

    Grage, M.M.-L.; Keszthelyi, T.; Offersgaard, J.F.; Wilbrandt, R.

    1998-01-01

    The resonance Raman spectrum of the photogenerated radical cation of bithiophene is reported. The bithiophene radical cation was produced via a photoinduced electron transfer reaction between excited bithiophene and the electron acceptor fumaronitrile in a room temperature acetonitrile solution a...... the Raman spectrum excited in resonance with the absorption band at 425 nm. The spectrum was interpreted with the help of density functional theory calculations. (C) 1998 Elsevier Science B.V.......The resonance Raman spectrum of the photogenerated radical cation of bithiophene is reported. The bithiophene radical cation was produced via a photoinduced electron transfer reaction between excited bithiophene and the electron acceptor fumaronitrile in a room temperature acetonitrile solution and...

  10. Incontinence and Erectile Dysfunction Following Radical Prostatectomy: A Review

    Directory of Open Access Journals (Sweden)

    Gerasimos Alivizatos

    2005-01-01

    Full Text Available Radical prostatectomy remains the treatment of choice for localized prostate cancer in age-appropriate and health-appropriate men. Although cancer control is the most important aspect of a radical prostatectomy, minimization of postoperative morbidity, especially urinary incontinence and erectile dysfunction, is becoming a greater concern. We reviewed recent data available on Medline regarding the incidence, pathophysiology, evaluation, and treatment of incontinence and sexual dysfunction after radical prostatectomy. Health-related quality of life issues have been specifically addressed. Although low incidences of incontinence and erectile dysfunction after radical prostatectomy have been reported in the hands of experienced surgeons, the literature review revealed a great variety, with incontinence rates ranging from 0.3–65.6% and potency rates ranging from 11–87%. Several factors contribute to this wide difference, the most important being the application of a meticulous surgical technique. General and cancer-specific health-related quality of life is not being affected after radical prostatectomy. The incidence of incontinence and erectile dysfunction is higher after radical prostatectomy when compared to the incidence observed when other therapies for localized prostate cancer are applied. However, the majority of the patients undergoing radical prostatectomy would vote for the operation again. Today, avoidance of major complications after radical prostatectomy depends mostly on a high-quality surgical technique. When incontinence or erectile dysfunction persists after radical prostatectomy, the majority of the treated patients can be managed effectively by various methods.

  11. Oxidation of benzene by radiolytically produced OH radicals

    International Nuclear Information System (INIS)

    The radiolysis of N2O saturated-aqueous solutions of benzene-14C has been examined using radio-liquid chromatographic methods to follow the quantitative aspects of the reactions of hydroxycyclohexadienyl radicals. In the absence of a radical oxidant, at least five important products are produced. The total yield of 5.8 observed for the incorporation of benzene into products accounts for essentially all of the radicals initially produced from the water. Dimeric products predominate with a total yield of 4.1. Phenol is produced with a yield of only 0.8 indicating a disproportionation/ combination ratio for hydroxycyclohexadienyl radicals of 2O saturated aqueous solutions. (author)

  12. Processing Chinese hand-radicals activates the medial frontal gyrus

    Institute of Scientific and Technical Information of China (English)

    Qing-Lin Wu; Yu-Chen Chan; Joseph P. Lavallee; Hsueh-Chin Chen; Kuo-En Chang; Yao-Ting Sung

    2013-01-01

    Embodied semantics theory asserts that the meaning of action-related words is neural y represented through networks that overlap with or are identical to networks involved in sory-motor processing. While some studies supporting this theory have focused on Chinese cha-racters, less attention has been paid to their semantic radicals. Indeed, there is stil disagreement about whether these radicals are processed independently. The present study investigated whether radicals are processed separately and, if so, whether this processing occurs in sensory-motor gions. Materials consisted of 72 high-frequency Chinese characters, with 18 in each of four ries:hand-action verbs with and without hand-radicals, and verbs not related to hand actions, with and without hand-radicals. Twenty-eight participants underwent functional MRI scans while reading the characters. Compared to characters without hand-radicals, reading characters with hand-radicals activated the right medial frontal gyrus. Verbs involving hand-action activated the left inferior parietal lobule, possibly reflecting integration of information in the radical with the semantic meaning of the verb. The findings may be consistent with embodied semantics theory and suggest that neural representation of radicals is indispensable in processing Chinese characters.

  13. Development of atomic radical monitoring probe and its application to spatial distribution measurements of H and O atomic radical densities in radical-based plasma processing

    International Nuclear Information System (INIS)

    Atomic radicals such as hydrogen (H) and oxygen (O) play important roles in process plasmas. In a previous study, we developed a system for measuring the absolute density of H, O, nitrogen, and carbon atoms in plasmas using vacuum ultraviolet absorption spectroscopy (VUVAS) with a compact light source using an atmospheric pressure microplasma [microdischarge hollow cathode lamp (MHCL)]. In this study, we developed a monitoring probe for atomic radicals employing the VUVAS with the MHCL. The probe size was 2.7 mm in diameter. Using this probe, only a single port needs to be accessed for radical density measurements. We successfully measured the spatial distribution of the absolute densities of H and O atomic radicals in a radical-based plasma processing system by moving the probe along the radial direction of the chamber. This probe allows convenient analysis of atomic radical densities to be carried out for any type of process plasma at any time. We refer to this probe as a ubiquitous monitoring probe for atomic radicals.

  14. Rovibronic Variational Calculations of the Nitrate Radical

    Science.gov (United States)

    Changala, Bryan; Baraban, Joshua H.; Stanton, John F.

    2015-06-01

    In recent years, sophisticated diabatic Hamiltonians have been developed in order to understand the low-energy vibronic level structure of the nitrate radical (NO_3), which exhibits strong coupling between the ~X and doubly degenerate ~B states. Previous studies have reproduced the observed vibronic level positions up to 2000 wn~above the zero-point level, yet the rotational structure has remained uninvestigated with ab initio methods. In this talk, we present calculations of the N≥0 rovibronic structure of low-lying vibronic states of NO_3, in which complicated rovibrational and Coriolis interactions have been observed. Our results include calculations using both adiabatic and diabatic Hamiltonians, enabling a direct comparison between the two. We discuss extensions of our treatment to include spin-orbit and spin-rotation effects.

  15. Interpersonal psychoanalysis' radical façade.

    Science.gov (United States)

    Hirsch, Irwin

    2002-01-01

    The participant-observation model initiated the relational turn, as well as the shift from modernism to postmodernism in psychoanalysis. This two-person, coparticipant conceptualization of the psychoanalytic situation moved psychoanalysis from the realm of alleged objective science toward intersubjectivity and hermeneutics. From this perspective, the analyst as subjective other is constantly engaged affectively with the patient in ways that are very often out of awareness. Analyst and patient both, for better or for worse, are believed to unwittingly influence one another. This description of the analytic dyad has led many to mistakingly conclude that interpersonal psychoanalysts advocate wittinly affective expressiveness, often in the form of deliberate self-disclosure of feelings, as part of a standard analytic stance. Upon closer examination, radical interventions are no more emblematic of interpersonal analysts than they are of analysts from most other traditions, though the interpersonalists have indeed expanded what had theretofore been a rather narrow repertoire of interventions. PMID:12597105

  16. Spectroscopy, Kinetics, and Dynamics of Combustion Radicals

    Energy Technology Data Exchange (ETDEWEB)

    Nesbitt, David J. [Research/Professor

    2013-08-06

    Spectroscopy, kinetics and dynamics of jet cooled hydrocarbon transients relevant to the DOE combustion mission have been explored, exploiting i) high resolution IR lasers, ii) slit discharge sources for formation of jet cooled radicals, and iii) high sensitivity detection with direct laser absorption methods and near the quantum shot noise limit. What makes this combination powerful is that such transients can be made under high concentrations and pressures characteristic of actual combustion conditions, and yet with the resulting species rapidly cooled (T ≈10-15K) in the slit supersonic expansion. Combined with the power of IR laser absorption methods, this provides novel access to spectral detection and study of many critical combustion species.

  17. Hyperfine interactions in muonium-containing radicals

    International Nuclear Information System (INIS)

    We present an overview of techniques designed for the reliable prediction of hyperfine interaction tensors in muonium-bearing radicals from Density Functional Theory (DFT). In general, the isotropic component is the most difficult to determine accurately. Anisotropic terms are often recovered satisfactorily at modest levels of theory. In small systems high-level electronic structure calculations may be used to demonstrate the importance of a number of key components in a successful treatment. The roles of basis set balance, electron correlation effects, and vibrational averaging over modes in which the muon is active are illustrated by calculations on a number of small inorganic and organic species. In larger systems DFT becomes the method of choice. However, the optimal choice of functional is not yet completely clear. Some cautionary tales are given along with some success stories

  18. Avoiding complications in radical neck dissection

    International Nuclear Information System (INIS)

    As reported previously, it remains our conclusion that the radical neck dissection can be performed expediently in a reasonable period of time, usually without the need of blood replacement, and is not characterized by major physiologic disability or wound complications secondary to the neck dissection alone. The presence of preoperative radiation, composite resections entering the oral cavity or pharynx, and systemic disease or debilitation, however, vastly enhance the risk of significant life threatening complications and prolong hospitalization; therefore, the use of post-operative radiation therapy in combined treatment, the use of planned fistulas and generally accepted reconstructive techniques, and a careful evaluation of the methods and technique for protection of the carotid artery are recommended

  19. Le Daghestan : islam populaire et islam radical

    OpenAIRE

    LONGUET-MARX, Frédérique

    2006-01-01

    De tradition soufie, l’islam revêt aujourd’hui des formes diverses – et parfois nouvelles – au Caucase du Nord-Est. Les confréries n’agissent plus dans l’opposition comme à l’époque soviétique mais font partie des instances officielles. L’islam populaire se développe avec un accroissement très sensible du nombre des cheikhs. Les lieux d’enseignement et de prière se multiplient. Le « wahhabisme », forme d’islam radical, se développe réellement au Daghestan au milieu des années 1980. Il est int...

  20. [URINARY DISCOMFORTS IN PATIENTS AFTER RADICAL PROSTATECTOMY].

    Science.gov (United States)

    Al'-Shukri, S Kh; Ananiĭ, I A; Amdiĭ, R E; Kuz'min, I V

    2015-01-01

    The authors showed the result of complication treatment of lower urinary tracts in 128 patients with localized prostate cancer. The patients underwent radical prostatectomy. Urinary discomforts included enuresis, urinary incontinence in postoperative period. Abnormalities of urine outflow due to urethral stricture were revealed in 6 (4,6%) patients by the 6 month after operation. These complications required surgical treatment. Urinary incontinence was noted in 20 (15,6%) patients in this period. It was stressful urinary incontinence in 16 (12,6%) and urgent - in 4 (3%). Patents with stressful urinary difficulty were advised to use the conservative treatment (pelvic floor muscle training and electrostimulation), but in case of inefficiency - surgical treatment. PMID:26390591