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Sample records for methyl n-2 pyridyl

  1. Synthesis of new 4-methyl-2-(4-pyridyl)-1,2,3,4-tetrahydroquinolines as potent antifungal compounds

    Energy Technology Data Exchange (ETDEWEB)

    Mendez, Leonor Y. Vargas [Universidad Santo Tomas, Bucaramanga (Colombia). Grupo de Investigaciones Ambientales; Zacchino, Susana A. [Universidad Nacional del Rosario, (Argentina). Lab. de Farmacognosia; Kouznetsov, Vladimir V. [Universidad Industrial de Santander, Bucaramanga (Colombia). Lab. de Quimica Organica y Biomolecular

    2010-07-01

    Synthesis, spectral characterization and biological results of new series of 2-(4-pyridyl)- 1,2,3,4-tetrahydroquinolines and their closer precursors, -N-aryl-N-[1-(4-pyridyl)but-3-enyl] amines are reported. It was found that both g-pyridyl substituted precursors and final products, tetrahydroquinolines, showed very good antifungal activities against Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Microsporum gypseun, Trichophyton rubrum and Trichophyton mentagrophytes. (author)

  2. (Carbonato-κO,O')bis-(di-2-pyridyl-amine-κN,N')cobalt(III) bromide.

    Science.gov (United States)

    Czapik, Agnieszka; Papadopoulos, Christos; Lalia-Kantouri, Maria; Gdaniec, Maria

    2011-04-01

    In the title compound, [Co(CO(3))(C(10)H(9)N(3))(2)]Br, a distorted octa-hedral coordination of the Co(III) atom is completed by four N atoms of the two chelating di-2-pyridyl-amine ligands and two O atoms of the chelating carbonate anion. The di-2-pyridyl-amine ligands are nonplanar and the dihedral angles between the 2-pyridyl groups are 29.11 (9) and 37.15 (12)°. The coordination cation, which has approximate C(2) symmetry, is connected to the bromide ion via an N-H⋯Br(-) hydrogen bond. The ionic pair thus formed is further assembled into a dimer via N-H⋯O inter-actions about an inversion centre. A set of weaker C-H⋯O and C-H⋯Br(-) inter-actions connect the dimers into a three-dimensional network.

  3. Synthesis and characterisation of dioxouranium(VI) and thorium(IV) complexes with 2(2'-pyridyl) 1-methyl benzimidazole

    International Nuclear Information System (INIS)

    Mohanty, R.R.; Rout, K.C.; Jena, S.; Dash, K.C.

    1995-01-01

    The ligand 2(2'-pyridyl) 1-methyl benzimidazole (MePB) forms a number of mononuclear complex of the type UO 2 (MePB)X 2 (X = Cl,I,NO 3 ,CH 3 COO,0.5 SO 4 ); UO 2 (MePB) 2 -(NCS) 2 and Th(MEPB) 2 X 4 (X = NO 3 ,NCS,I) and the biheteronuclear complex UO 2 (MePB)HgCl 4 . All these complexes were characterised by elemental analysis, conductivity measurements, thermogravimetric studies and IR, electronic, mass and NMR ( 1 H and 13 C) spectral studies. (author). 5 refs

  4. (2-Pyridyl[5-(2-pyridylcarbonyl-2-pyridyl]methanone

    Directory of Open Access Journals (Sweden)

    Zi-jia Wang

    2010-10-01

    Full Text Available In the centrosymmetric title compound, C17H11N3O2, the dihedral angle between the central and pendant pyridyl rings is 50.29 (9°. In the crystal, molecules stack along the a axis by π–π interactions between the pyridine rings with centroid–centroid distances of 3.845 (2 Å. The N atom and one of the C atoms of the central ring are disordered by symmetry.

  5. C-C bond formation and related reactions at the CNC backbone in (smif)FeX (smif = 1,3-di-(2-pyridyl)-2-azaallyl): dimerizations, 3 + 2 cyclization, and nucleophilic attack; transfer hydrogenations and alkyne trimerization (X = N(TMS)2, dpma = (di-(2-pyridyl-methyl)-amide)).

    Science.gov (United States)

    Frazier, Brenda A; Williams, Valerie A; Wolczanski, Peter T; Bart, Suzanne C; Meyer, Karsten; Cundari, Thomas R; Lobkovsky, Emil B

    2013-03-18

    Molecular orbital analysis depicts the CNC(nb) backbone of the smif (1,3-di-(2-pyridyl)-2-azaallyl) ligand as having singlet diradical and/or ionic character where electrophilic or nucleophilic attack is plausible. Reversible dimerization of (smif)Fe{N(SiMe3)2} (1) to [{(Me3Si)2N}Fe]2(μ-κ(3),κ(3)-N,py2-smif,smif) (2) may be construed as diradical coupling. A proton transfer within the backbone-methylated, and o-pyridine-methylated smif of putative ((b)Me2(o)Me2smif)FeN(SiMe3)2 (8) provides a route to [{(Me3Si)2N}Fe]2(μ-κ(4),κ(4)-N,py2,C-((b)Me,(b)CH2,(o)Me2(smif)H))2 (9). A 3 + 2 cyclization of ditolyl-acetylene occurs with 1, leading to the dimer [{2,5-di(pyridin-2-yl)-3,4-di-(p-tolyl-2,5-dihydropyrrol-1-ide)}FeN(SiMe3)2]2 (11), and the collateral discovery of alkyne cyclotrimerization led to a brief study that identified Fe(N(SiMe3)2(THF) as an effective catalyst. Nucleophilic attack by (smif)2Fe (13) on (t)BuNCO and (2,6-(i)Pr2C6H3)NCO afforded (RNHCO-smif)2Fe (14a, R = (t)Bu; 14b, 2,6-(i)PrC6H3). Calculations suggested that (dpma)2Fe (15) would favorably lose dihydrogen to afford (smif)2Fe (13). H2-transfer to alkynes, olefins, imines, PhN═NPh, and ketones was explored, but only stoichiometric reactions were affected. Some physical properties of the compounds were examined, and X-ray structural studies on several dinuclear species were conducted.

  6. Rhenium and technetium complexes with phenylbis(2-pyridyl)phosphine and tris(2-pyridyl)phosphine

    Energy Technology Data Exchange (ETDEWEB)

    Saucedo A, S. A. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Hagenbach, A.; Abram, U., E-mail: ssaucedo@uaz.edu.m [Institut fur Chemie und Biochemie, Freie Universitat Berlin, Fabeckstr. 34-36, D-14195, Berlin (Germany)

    2010-10-15

    Reactions of common technetium and rhenium precursors with 2-pyridyl phosphines produce novel, air stable tricarbonyl and oxo complexes. (NEt{sub 4}){sub 2}[Re(CO){sub 3}Br{sub 3}] or (NEt{sub 4}){sub 2}[Tc(CO){sub 3}Cl{sub 3}] react with phenylbis(2-pyridyl)phosphine (PPhpy{sub 2}) or tris(2-pyridyl)phosphine (Ppy{sub 3}) under formation of neutral tricarbonyl complexes of the composition [M(CO){sub 3}X(L)] (M = Re, X = Br; M = Tc, X = Cl, L = PPhpy{sub 2} or Ppy{sub 3}), where the ligands coordinate only with two for their nitrogen atoms. Removal of the bromo ligands from (NEt{sub 4}){sub 2}[Re(CO){sub 3}(Br){sub 3}] with AgNO{sub 3}, to force a tripodal coordination, and the subsequent reaction with the Ppy{sub 3} results in the formation of the complex [Re(CO){sub 3}(NO{sub 3})(Ppy{sub 3}{sup -}N,N{sup '})] with a monodentate coordinated nitrato ligand. (NBu{sub 4})[ReOCl{sub 4}] reacts with PPhpy{sub 2} to give the asymmetric, oxo-bridged rhenium (V) dimer (NBu{sub 4})[Re{sub 2}O{sub 2}Cl{sub 5}({mu}-PPhpy{sub 2}{sup -}P,N,N,N{sup '})({mu}-O)], while a similar reaction with (ReOCl{sub 3}(PPh{sub 3}){sub 2}] in boiling Thf results in reduction of the metal and gives (ReCl{sub 3}(OPPhpy{sub 2})(PPh{sub 3})]. The products have been characterized spectroscopically and by X-ray structure analyses. (Author)

  7. (Carbonato-κ2 O,O′)bis­(di-2-pyridyl­amine-κ2 N,N′)cobalt(III) bromide

    Science.gov (United States)

    Czapik, Agnieszka; Papadopoulos, Christos; Lalia-Kantouri, Maria; Gdaniec, Maria

    2011-01-01

    In the title compound, [Co(CO3)(C10H9N3)2]Br, a distorted octa­hedral coordination of the CoIII atom is completed by four N atoms of the two chelating di-2-pyridyl­amine ligands and two O atoms of the chelating carbonate anion. The di-2-pyridyl­amine ligands are nonplanar and the dihedral angles between the 2-pyridyl groups are 29.11 (9) and 37.15 (12)°. The coordination cation, which has approximate C 2 symmetry, is connected to the bromide ion via an N—H⋯Br− hydrogen bond. The ionic pair thus formed is further assembled into a dimer via N—H⋯O inter­actions about an inversion centre. A set of weaker C—H⋯O and C—H⋯Br− inter­actions connect the dimers into a three-dimensional network. PMID:21753946

  8. Stable isotope labeling-mass spectrometry analysis of methyl- and pyridyloxobutyl-guanine adducts of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone in p53-derived DNA sequences.

    Science.gov (United States)

    Rajesh, Mathur; Wang, Gang; Jones, Roger; Tretyakova, Natalia

    2005-02-15

    The p53 tumor suppressor gene is a primary target in smoking-induced lung cancer. Interestingly, p53 mutations observed in lung tumors of smokers are concentrated at guanine bases within endogenously methylated (Me)CG dinucleotides, e.g., codons 157, 158, 245, 248, and 273 ((Me)C = 5-methylcytosine). One possible mechanism for the increased mutagenesis at these sites involves targeted binding of metabolically activated tobacco carcinogens to (Me)CG sequences. In the present work, a stable isotope labeling HPLC-ESI(+)-MS/MS approach was employed to analyze the formation of guanine lesions induced by the tobacco-specific lung carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) within DNA duplexes representing p53 mutational "hot spots" and surrounding sequences. Synthetic DNA duplexes containing p53 codons 153-159, 243-250, and 269-275 were prepared, where (Me)C was incorporated at all physiologically methylated CG sites. In each duplex, one of the guanine bases was replaced with [1,7,NH(2)-(15)N(3)-2-(13)C]-guanine, which served as an isotope "tag" to enable specific quantification of guanine lesions originating from that position. After incubation with NNK diazohydroxides, HPLC-ESI(+)-MS/MS analysis was used to determine the yields of NNK adducts at the isotopically labeled guanine and at unlabeled guanine bases elsewhere in the sequence. We found that N7-methyl-2'-deoxyguanosine and N7-[4-oxo-4-(3-pyridyl)but-1-yl]guanine lesions were overproduced at the 3'-guanine bases within polypurine runs, while the formation of O(6)-methyl-2'-deoxyguanosine and O(6)-[4-oxo-4-(3-pyridyl)but-1-yl]-2'-deoxyguanosine adducts was specifically preferred at the 3'-guanine base of 5'-GG and 5'-GGG sequences. In contrast, the presence of 5'-neighboring (Me)C inhibited O(6)-guanine adduct formation. These results indicate that the N7- and O(6)-guanine adducts of NNK are not overproduced at the endogenously methylated CG dinucleotides within the p53 tumor suppressor gene

  9. (15)N NMR spectroscopy unambiguously establishes the coordination mode of the diimine linker 2-(2'-pyridyl)pyrimidine-4-carboxylic acid (cppH) in Ru(ii) complexes.

    Science.gov (United States)

    Battistin, Federica; Balducci, Gabriele; Demitri, Nicola; Iengo, Elisabetta; Milani, Barbara; Alessio, Enzo

    2015-09-21

    We investigated the reactivity of three Ru(ii) precursors -trans,cis,cis-[RuCl2(CO)2(dmso-O)2], cis,fac-[RuCl2(dmso-O)(dmso-S)3], and trans-[RuCl2(dmso-S)4] - towards the diimine linker 2-(2'-pyridyl)pyrimidine-4-carboxylic acid (cppH) or its parent compound 4-methyl-2-(2'-pyridyl)pyrimidine ligand (mpp), in which a methyl group replaces the carboxylic group on the pyrimidine ring. In principle, both cppH and mpp can originate linkage isomers, depending on how the pyrimidine ring binds to ruthenium through the nitrogen atom ortho (N(o)) or para (N(p)) to the group in position 4. The principal aim of this work was to establish a spectroscopic fingerprint for distinguishing the coordination mode of cppH/mpp also in the absence of an X-ray structural characterization. By virtue of the new complexes described here, together with the others previously reported by us, we successfully recorded {(1)H,(15)N}-HMBC NMR spectra at natural abundance of the (15)N isotope on a consistent number of fully characterized Ru(ii)-cppH/mpp compounds, most of them being stereoisomers and/or linkage isomers. Thus, we found that (15)N NMR chemical shifts unambiguously establish the binding mode of cppH and mpp - either through N(o) or N(p)- and can be conveniently applied also in the absence of the X-ray structure. In fact, coordination of cppH to Ru(ii) induces a marked upfield shift for the resonance of the N atoms directly bound to the metal, with coordination induced shifts (CIS) ranging from ca.-45 to -75 ppm, depending on the complex, whereas the unbound N atom resonates at a frequency similar to that of the free ligand. Similar results were found for the complexes of mpp. This work confirmed our previous finding that cppH has no binding preference, whereas mpp binds exclusively through N(p). Interestingly, the two cppH linkage isomers trans,cis-[RuCl2(CO)2(cppH-κN(p))] (5) and trans,cis-[RuCl2(CO)2(cppH-κN(o))] (6) were easily obtained in pure form by exploiting their different

  10. Endogenous 5-methylcytosine protects neighboring guanines from N7 and O6-methylation and O6-pyridyloxobutylation by the tobacco carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone.

    Science.gov (United States)

    Ziegel, Rebecca; Shallop, Anthony; Upadhyaya, Pramod; Jones, Roger; Tretyakova, Natalia

    2004-01-20

    All CG dinucleotides along exons 5-8 of the p53 tumor suppressor gene contain endogenous 5-methylcytosine (MeC). These same sites (e.g., codons 157, 158, 245, 248, and 273) are mutational hot spots in smoking-induced lung cancer. Several groups used the UvrABC endonuclease incision assay to demonstrate that methylated CG dinucleotides of the p53 gene are the preferred binding sites for the diol epoxides of bay region polycyclic aromatic hydrocarbons (PAH). In contrast, effects of endogenous cytosine methylation on the distribution of DNA lesions induced by tobacco-specific nitrosamines, e.g., 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), have not been elucidated. In the work presented here, a stable isotope labeling HPLC-ESI-MS/MS approach was employed to analyze the reactivity of the N7 and O6 positions of guanines within hemimethylated and fully methylated CG dinucleotides toward NNK-derived methylating and pyridyloxobutylating species. 15N3-labeled guanine bases were placed within synthetic DNA sequences representing endogenously methylated p53 codons 154, 157, and 248, followed by treatment with acetylated precursors to NNK diazohydroxides. HPLC-ESI-MS/MS analysis was used to determine the relative yields of N7- and O6-guanine adducts at the 15N3-labeled position. In all cases, the presence of MeC inhibited the formation of N7-methylguanine, O6-methylguanine, and O6-pyridyloxobutylguanine at a neighboring G, with the greatest decrease observed in fully methylated dinucleotides and at guanines preceded by MeC. Furthermore, the O6-Me-dG/N7-Me-G molar ratios were decreased in the presence of the 5'-neighboring MeC, suggesting that the observed decline in O6-alkylguanine adduct yields is, at least partially, a result of an altered reactivity pattern in methylated CG dinucleotides. These results indicate that, unlike N2-guanine adducts of PAH diol epoxides, NNK-induced N7- and O6-alkylguanine adducts are not preferentially formed at the endogenously

  11. Kinetics and reaction mechanism for aminolysis of benzyl 4-pyridyl carbonate in H2O: Effect of modification of nucleofuge from 2-pyridyl oxide to 4-pyridyl oxide on reactivity and reaction mechanism

    International Nuclear Information System (INIS)

    Kang, Ji Sun; Um, Ikhwan

    2012-01-01

    Pseudo-first-order rate constants k amine have been measured spectrophotometrically for the reactions of benzyl 4-pyridyl carbonate 6 with a series of alicyclic secondary amines in H 2 O at 25.0.deg.C. The plots of k amine vs. [amine] curve upward, indicating that the reactions proceed through a stepwise mechanism with two intermediates, a zwitterionic tetrahedral intermediate T ± and its deprotonated form T - . This contrasts to the report that the corresponding reactions of benzyl 2-pyridyl carbonate 5 proceed through a forced concerted pathway. The k amine values for the reactions of 6 have been dissected into the second-order rate constant Kk 2 and the third order rate constant Kk 3 . The Brφnsted-type plots are linear with β nuc = 0.94 and 1.18 for Kk 2 and Kk 3 , respectively. The Kk 2 for the reaction of 6 is smaller than the second-order rate constant k N for the corresponding reaction of 5, although 4-pyridyl oxide in 6 is less basic and a better nucleofuge than 2-pyridyl oxide in 5

  12. The coordination chemistry of the neutral tris-2-pyridyl silicon ligand [PhSi(6-Me-2-py)3].

    Science.gov (United States)

    Plajer, Alex J; Colebatch, Annie L; Enders, Markus; García-Romero, Álvaro; Bond, Andrew D; García-Rodríguez, Raúl; Wright, Dominic S

    2018-05-22

    Difficulties in the preparation of neutral ligands of the type [RSi(2-py)3] (where 2-py is an unfunctionalised 2-pyridyl ring unit) have thwarted efforts to expand the coordination chemistry of ligands of this type. However, simply switching the pyridyl substituents to 6-methyl-pyridyl groups (6-Me-2-py) in the current paper has allowed smooth, high-yielding access to the [PhSi(6-Me-2-py)3] ligand (1), and the first exploration of its coordination chemistry with transition metals. The synthesis, single-crystal X-ray structures and solution dynamics of the new complexes [{PhSi(6-Me-2-py)3}CuCH3CN][PF6], [{PhSi(6-Me-2-py)3}CuCH3CN][CuCl2], [{PhSi(6-Me-2-py)3}FeCl2], [{PhSi(6-Me-2-py)3}Mo(CO)3] and [{PhSi(6-Me-2-py)3}CoCl2] are reported. The paramagnetic Fe2+ and Co2+ complexes show strongly shifted NMR resonances for the coordinated pyridyl units due to large Fermi-contact shifts. However, magnetic anisotropy also leads to considerable pseudo-contact shifts so that both contributions have to be included in the paramagnetic NMR analysis.

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

    International Nuclear Information System (INIS)

    Haga, Masaaki; Tanaka, Toshio.

    1979-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1979-07-01

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

  15. A novel chlorine derivative of Meso-tris(pentafluorophenyl)-4-pyridyl porphyrin: synthesis, photophysics and photochemical properties

    Energy Technology Data Exchange (ETDEWEB)

    Maestrin, Ana Paula J.; Ribeiro, Anderson O.; Tedesco, Antonio Claudio; Neri, Claudio R.; Vinhado, Fabio S.; Serra, Osvaldo A.; Martins, Patricia R.; Iamamoto, Yassuko [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Inst. de Quimica]. E-mail: oaserra@ffclrp.usp.br; Silva, Ana Margarida G.; Tome, Augusto C.; Neves, Maria G.P.M.S.; Cavaleiro, Jose A.S. [Universidade de Aveiro (Portugal). Dept. de Quimica]. E-mail: jcavaleiro@dq.ua.pt

    2004-12-01

    Photodynamic therapy (PDT) is based on the accumulation of a photosensitizer, such as a porphyrin or a chlorine, in a malignant tissue after its administration. Chlorins exhibit photophysical properties similar to those of the porphyrin macrocycles, but with intensified and red-shifted Q bands, making chlorine-containing systems even better candidates for PDT. In this contribution, we report the synthesis of 5,10,15-tris(pentafluorophenyl)-20-(4-pyridyl)porphyrin, (2) and its transformation to the novel chlorine derivatives 4, (5,10,20-tris(pentafluorophenyl)-15-(4-pyridyl)-tetrahydro-1H- N-methyl-pyrrolo [3,4-b]porphyrin and 5, (5,10,15-tris(pentafluorophenyl)-20-(4-pyridyl)-tetrahydro-1H- N-methyl-pyrrolo[3,4-b]porphyrin) by 1,3-dipolar cycloaddition with an azomethine ylide. The new products have been characterized by UV-Vis, {sup 1}H NMR and FAB-MS. The photophysics, photochemical and photobleaching properties of chlorine 4 have been evaluated. Its quantum yield of photobleaching ({phi}{sub Pb}, mol Einstein{sup -1}) was 0.047{+-}0.014. In order to demonstrate the production of {sup 1}O{sub 2} when 4 is used as a photosensitizer, uric acid tests have been carried out. The results indicate that chlorine 4 can be considered a promising photosensitizer in PDT. (author)

  16. A novel chlorine derivative of Meso-tris(pentafluorophenyl)-4-pyridyl porphyrin: synthesis, photophysics and photochemical properties

    International Nuclear Information System (INIS)

    Maestrin, Ana Paula J.; Ribeiro, Anderson O.; Tedesco, Antonio Claudio; Neri, Claudio R.; Vinhado, Fabio S.; Serra, Osvaldo A.; Martins, Patricia R.; Iamamoto, Yassuko; Silva, Ana Margarida G.; Tome, Augusto C.; Neves, Maria G.P.M.S.; Cavaleiro, Jose A.S.

    2004-01-01

    Photodynamic therapy (PDT) is based on the accumulation of a photosensitizer, such as a porphyrin or a chlorine, in a malignant tissue after its administration. Chlorins exhibit photophysical properties similar to those of the porphyrin macrocycles, but with intensified and red-shifted Q bands, making chlorine-containing systems even better candidates for PDT. In this contribution, we report the synthesis of 5,10,15-tris(pentafluorophenyl)-20-(4-pyridyl)porphyrin, (2) and its transformation to the novel chlorine derivatives 4, (5,10,20-tris(pentafluorophenyl)-15-(4-pyridyl)-tetrahydro-1H- N-methyl-pyrrolo [3,4-b]porphyrin and 5, (5,10,15-tris(pentafluorophenyl)-20-(4-pyridyl)-tetrahydro-1H- N-methyl-pyrrolo[3,4-b]porphyrin) by 1,3-dipolar cycloaddition with an azomethine ylide. The new products have been characterized by UV-Vis, 1 H NMR and FAB-MS. The photophysics, photochemical and photobleaching properties of chlorine 4 have been evaluated. Its quantum yield of photobleaching (φ Pb , mol Einstein -1 ) was 0.047±0.014. In order to demonstrate the production of 1 O 2 when 4 is used as a photosensitizer, uric acid tests have been carried out. The results indicate that chlorine 4 can be considered a promising photosensitizer in PDT. (author)

  17. Concurrent coordination of ligand in metal chloride complexes with 1-vinyl-2-(2-pyridyl)benzimidazole

    International Nuclear Information System (INIS)

    Bajkalov, L.V.; Domnina, E.S.

    1996-01-01

    The properties and structure of bivalent cadmium and 1-vinyl-2-(2-pyridyl)benzimidazole chloride complexes, which have been prepared for the first time, have been studied by the methods of potentiometric titration and PMR, 35 Cl NQR, UV and IR spectroscopy. For the complexes above di- and polymeric structures in crystal phase are suggested, where ligand plays the role of a bridge. N,N-bidentate ligand. In solution the complexes dissociate with formation of monomeric coordination compounds, their metal being bound by different ways, stemming from participation of N benzimidazole or pyridine fragment of the ligand. Adducts of ionic type with second sphere 1-vinyl-2-(2-pyridyl)benzimidazole cation have been obtained in the course of hydrochlorination of the complexes prepared

  18. A highly sensitive amperometric sensor for oxygen based on iron(II) tetrasulfonated phthalocyanine and iron(III) tetra-(N-methyl-pyridyl)-porphyrin multilayers

    International Nuclear Information System (INIS)

    Duarte, Juliana C.; Luz, Rita C.S.; Damos, Flavio S.; Tanaka, Auro A.; Kubota, Lauro T.

    2008-01-01

    The development of a highly sensitive sensor for oxygen is proposed using a glassy carbon (GC) electrode modified with alternated layers of iron(II) tetrasulfonated phthalocyanine (FeTsPc) and iron(III) tetra-(N-methyl-pyridyl)-porphyrin (FeT4MPyP). The modified electrode showed excellent catalytic activity for the oxygen reduction. The reduction potential of the oxygen was shifted about 330 mV toward less negative values with this modified electrode, presenting a peak current much higher than those observed on a bare GC electrode. Cyclic voltammetry and rotating disk electrode (RDE) experiments indicated that the oxygen reduction reaction involves 4 electrons with a heterogenous rate constant (k obs ) of 3 x 10 5 mol -1 L s -1 . A linear response range from 0.2 up to 6.4 mg L -1 , with a sensitivity of 4.12 μA L mg -1 (or 20.65 μA cm -2 L mg -1 ) and a detection limit of 0.06 mg L -1 were obtained with this sensor. The repeatability of the proposed sensor, evaluated in terms of relative standard deviation (R.S.D.) was 2.0% for 10 measurements of a solution of 6.4 mg L -1 oxygen. The sensor was applied to determine oxygen in pond and tap water samples showing to be a promising tool for this purpose

  19. Rhenium Complexes Based on 2-Pyridyl-1,2,3-triazole Ligands: A New Class of CO2 Reduction Catalysts.

    Science.gov (United States)

    Ching, H Y Vincent; Wang, Xia; He, Menglan; Perujo Holland, Noemi; Guillot, Régis; Slim, Cyrine; Griveau, Sophie; Bertrand, Hélène C; Policar, Clotilde; Bedioui, Fethi; Fontecave, Marc

    2017-03-06

    A series of [Re(N^N)(CO) 3 (X)] (N^N = diimine and X = halide) complexes based on 4-(2-pyridyl)-1,2,3-triazole (pyta) and 1-(2-pyridyl)-1,2,3-triazole (tapy) diimine ligands have been prepared and electrochemically characterized. The first ligand-based reduction process is shown to be highly sensitive to the nature of the isomer as well as to the substituents on the pyridyl ring, with the peak potential changing by up to 700 mV. The abilities of this class of complexes to catalyze the electroreduction and photoreduction of CO 2 were assessed for the first time. It is found that only Re pyta complexes that have a first reduction wave with a peak potential at ca. -1.7 V vs SCE are active, producing CO as the major product, together with small amounts of H 2 and formic acid. The catalytic wave that is observed in the CVs is enhanced by the addition of water or trifluoroethanol as a proton source. Long-term controlled potential electrolysis experiments gave total Faradaic yield close to 100%. In particular, functionalization of the triazolyl ring with a 2,4,6-tri-tert-butylphenyl group provided the catalyst with a remarkable stability.

  20. Oxovanadium(IV) complexes with tridentate dibasic schiff base ligands and 2-(2'-pyridyl) benzimidazole

    Energy Technology Data Exchange (ETDEWEB)

    Mohanty, R N; Chakravortty, V; Dash, K C [Utkal Univ., Bhubaneswar (India). Dept. of Chemistry

    1991-05-01

    The present work deals with the monomeric, six-coordinated mixed-ligand complexes of oxovanadium(IV) with dibasic tridentate schiff base ligands(ONO donor set) and the bidentate chelating ligand 2-(2'-pyridyl)benzimidazole (PBH) containing N{sub 2} donor set. (author). 1 tab., 22 refs.

  1. Formation of formaldehyde adducts in the reactions of DNA and deoxyribonucleosides with alpha-acetates of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), and N-nitrosodimethylamine (NDMA).

    Science.gov (United States)

    Cheng, Guang; Wang, Mingyao; Upadhyaya, Pramod; Villalta, Peter W; Hecht, Stephen S

    2008-03-01

    The cytochrome P450-mediated alpha-hydroxylation of the carcinogenic nitrosamines N-nitrosodimethylamine (NDMA, 1), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK, 6a), and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL, 6b) produces diazonium ions and formaldehyde. The DNA-binding properties of the diazonium ions have been thoroughly characterized, and there is no doubt that they are critical in cancer induction by these nitrosamines. However, the possibility of additional DNA damage via released formaldehyde has not been reported. In this study, we used acetoxymethylmethylnitrosamine (5), 4-(acetoxymethylnitrosamino)-1-(3-pyridyl)-1-butanone (10a), and 4-(acetoxymethylnitrosamino)-1-(3-pyridyl)-1-butanol (10b) as stable precursors to the alpha-hydroxymethylnitrosamines that would be formed in the metabolism of NDMA, NNK, and NNAL. These alpha-acetates were incubated with calf thymus DNA in the presence of esterase at pH 7.0 and 37 degrees C. The DNA was isolated and enzymatically hydrolyzed to deoxyribonucleosides, and the hydrolysates were analyzed by liquid chromatography-electrospray ionization-mass spectrometry-selected ion monitoring for formaldehyde DNA adducts. Convincing evidence for the formation of the formaldehyde adducts N6-hydroxymethyl-dAdo (11), N4-hydroxymethyl-dCyd (12), N2-hydroxymethyl-dGuo (13), and the cross-links di-(N6-deoxyadenosyl)methane (14), (N6-deoxyadenosyl- N2-deoxyguanosyl)methane (15), and di-(N2-deoxyguanosyl)methane (16) was obtained in these reactions. These results demonstrate that NDMA, NNK, and NNAL have the potential to be bident carcinogens, damaging DNA through the metabolic formation of both diazonium ions and formaldehyde.

  2. Magnetic and Photo-Physical Properties of Lanthanide Dinuclear Complexes Involving the 4,5-Bis(2-Pyridyl-N-Oxidemethylthio-4′,5′-Dicarboxylic Acid-Tetrathiafulvalene-, Dimethyl Ester Ligand

    Directory of Open Access Journals (Sweden)

    Fabrice Pointillart

    2015-12-01

    Full Text Available The reaction between the 4,5-bis(2-pyridyl-N-oxidemethylthio-4′,5′-dicarboxylic acid-tetrathiafulvalene-, dimethyl ester ligand (L and the metallo-precursors Ln(hfac3·2H2O leads to the formation of two dinuclear complexes of formula [Ln2(hfac6(L]·(CH2Cl2·(C6H140.5 (LnIII = DyIII (1 and YbIII (2. The X-ray structure reveals a quite regular square anti-prism symmetry for the coordination sphere of the lanthanide ion. UV-visible absorption properties have been experimentally measured and rationalized by TD-DFT calculations. The functionalization of the tetrathiafulvalene (TTF core by two methyl ester moieties induces the appearance of an additional absorption band in the lowest-energy region of the spectrum. The latter has been identified as a HOMO (Highest Occupied Molecular Orbital→LUMO (Lowest Unoccupied Molecular Orbital Intra-Ligand Charge Transfer (ILCT transition in which the HOMO and LUMO are centred on the TTF and methyl ester groups, respectively. Irradiation at 22,222 cm−1 of this ILCT band induces an efficient sensitization of the YbIII-centred emission that can be correlated to the magnetic properties.

  3. Nephelauxetic and hypersensitive nature of neodymium(III) complexes with α-pyridyl-thiosemicarbazide and its furfural-2-aldehyde and thiophene-2-aldehyde derivatives

    International Nuclear Information System (INIS)

    Jain, C.L.; Mundley, P.N.; Khandelwal, B.E.

    1986-01-01

    A new series of octahedral Nd(III) complexes with recently synthesised α-pyridylthiosemicarbazide (C 6 H 8 N 4 S or 'PT'), N-(α-pyridyl)furfural-2-aldehyde-thiosemicarbazone (C 11 H 10 N 4 SO or 'PFT') and N-(α-pyridyl)thiophene-2-aldehyde-thiosemicarbazone (C 11 H 10 N 4 S 2 or 'PTT'), have been isolated and characterised on the basis of their elemental analysis, magnetic and reflectance and ir spectral data revealing 'PT' as bidentate (pyridinic-N and thioketo-S) and 'PFT' and 'PTT' as tetradentate with pyridinic-N, thioketo-S, imine-N and furfuryl-O/thiophenyl-S as donor sites. Isolation and characterisation of Nd(III) complexes with 'PT', 'PFT' and 'PTT' and their nephelauxetic and hypersensitive nature are studied in order to evaluate the stereochemistry of the ligands around Nd(III) ion. (author). 12 refs., 2 tables

  4. Synthesis and characterization of novel substituted 3,6-bis(2-pyridyl)pyridazine metal-coordinating ligands

    NARCIS (Netherlands)

    Hoogenboom, R.; Kickelbick, G.; Schubert, U.S.

    2003-01-01

    The synthesis of novel functionalized 3,6-di(2-pyridyl)pyridazines via an inverse electron demand Diels-Alder reaction between the corresponding 3,6-di(2-pyridyl)-1,2,4,5-tetrazine and various alkynes is reported. The resulting 3,6-di(2-pyridyl)pyridazines were investigated using X-ray

  5. Pd(II)-catalyzed di-o-olefination of carbazoles directed by the protecting N-(2-pyridyl)sulfonyl group.

    Science.gov (United States)

    Urones, Beatriz; Gómez Arrayás, Ramón; Carretero, Juan Carlos

    2013-03-01

    Despite the significance of carbazole in pharmacy and material science, examples of the direct C-H functionalization of this privileged unit are quite rare. The N-(2-pyridyl)sulfonyl group enables the Pd(II)-catalyzed ortho-olefination of carbazoles and related systems, acting as both a directing and readily removable protecting group. This method features ample structural versatility, affording typically the double ortho-olefination products (at C1 and C8) in satisfactory yields and complete regiocontrol. The application of this procedure to related heterocyclic systems, such as indoline, is also described.

  6. Tris(dibenzoylmethanido-κ2O,O′[(6S,8S-(+-7,7-dimethyl-3-(2-pyridyl-5,6,7,8-tetrahydro-6,8-methanoisoquinoline-κ2N,N′]gadolinium(III

    Directory of Open Access Journals (Sweden)

    Xi-Li Li

    2009-09-01

    Full Text Available In the title compound, [Gd(C15H11O23(C17H18N2], the GdIII atom is coordinated by six O atoms from three β-diketonate ligands and two N atoms from a chiral ligand LS,S-(+-7,7-dimethyl-3-(2-pyridyl-5,6,7,8-tetrahydro-6,8-methanoisoquinoline, in a coordination geometry best described as distorted square-antiprismatic.

  7. 3-Phenyl-6-(2-pyridyl-1,2,4,5-tetrazine

    Directory of Open Access Journals (Sweden)

    Daniel Chartrand

    2008-01-01

    Full Text Available The title compound, C13H9N5, is the first asymmetric diaryl-1,2,4,5-tetrazine to be crystallographically characterized. We have been interested in this motif for incorporation into supramolecular assemblies based on coordination chemistry. The solid state structure shows a centrosymmetric molecule, forcing a positional disorder of the terminal phenyl and pyridyl rings. The molecule is completely planar, unusual for aromatic rings with N atoms in adjacent ortho positions. The stacking observed is very common in diaryltetrazines and is dominated by π stacking [centroid-to-centroid distance between the tetrazine ring and the aromatic ring of an adjacent molecule is 3.6 Å, perpendicular (centroid-to-plane distance of about 3.3 Å].

  8. Complexes of molybdenum(III) with 2-(2'-pyridyl)benzimidazole

    International Nuclear Information System (INIS)

    Ghosh, S.P.; Prasad, K.M.

    1979-01-01

    Molybdenum(III) forms with 2-(2'-pyridyl) benzimidazole(LH) the trischelated complexes, [Mo(LH) 3 ]X 3 as well as the cationic-anionic complexes, [Mo(LH) 3 X 2 ] + [Mo(LH)X 4 ] - (X=Cl - ,Br - or NCS - ), depending on pH. These complexes have been synthesised and characterised from elemental analyses, i.r. and electronic spectra, magnetic moments and molar conductance. (auth.)

  9. Structural and biological evaluation of some metal complexes of vanillin-4N-(2-pyridyl) thiosemicarbazone

    Science.gov (United States)

    Yousef, T. A.; Abu El-Reash, G. M.; Al-Jahdali, M.; El-Rakhawy, El-Bastawesy R.

    2013-12-01

    The synthesis and characterization of Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II) and U(VI)O2 complexes of vanillin-4N-(2-pyridyl) thiosemicarbazone (H2PVT) are reported. Theoretical calculations have been performed to obtain IR spectra of ligand and its complexes using AM1, Zindo/1, MM+ and PM3, methods. The Schiff base and its metal complexes have been screened for antibacterial Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis and Staphylococcus saprophyticus. H2VPT shows no apparent digestion effect on the egg albumin while Mn(II), Hg(II) and Cu(II) complexes exhibited a considerable digestion effect following the order Cu(II) > Mn(II) > Hg(II). Moreover, Ni(II) and Co(II) complexes revealed strong digestion effect. Fe(II), Mn(II), Cu(II), Zn(II) and Ni(II) acted as metal co- SOD enzyme factors, which are located in different compartments of the cell.

  10. K-ras gene sequence effects on the formation of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-DNA adducts.

    Science.gov (United States)

    Ziegel, Rebecca; Shallop, Anthony; Jones, Roger; Tretyakova, Natalia

    2003-04-01

    The tobacco specific pulmonary carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is metabolically activated to electrophilic species that form methyl and pyridyloxobutyl adducts with genomic DNA, including O(6)-methylguanine, N7-methylguanine, and O(6)-[4-oxo-4-(3-pyridyl)butyl]guanine. If not repaired, these lesions could lead to mutations and the initiation of cancer. Previous studies used ligation-mediated polymerase chain reaction (LMPCR) in combination with PAGE to examine the distribution of NNK-induced strand breaks and alkali labile lesions (e.g., N7-methylguanine) within gene sequences. However, LMPCR cannot be used to establish the distribution patterns of highly promutagenic O(6)-methylguanine and O(6)-[4-oxo-4-(3-pyridyl)butyl]guanine adducts of NNK. We have developed methods based on stable isotope labeling HPLC-electrospray ionization tandem mass spectrometry (HPLC-ESI MS/MS) that enable us to accurately quantify NNK-induced adducts at defined sites within DNA sequences. In the present study, the formation of N7-methylguanine, O(6)-methylguanine, and O(6)-[4-oxo-4-(3-pyridyl)butyl]guanine adducts at specific positions within a K-ras gene-derived double-stranded DNA sequence (5'-G(1)G(2)AG(3)CTG(4)G(5)TG(6)G(7)CG(8)TA G(9)G(10)C-3') was investigated following treatment with activated NNK metabolites. All three lesions preferentially formed at the second position of codon 12 (GGT), the major mutational hotspot for G-->A and G-->T base substitutions observed in smoking-induced lung tumors. Therefore, our data support the involvement of NNK and other tobacco specific nitrosamines in mutagenesis and carcinogenesis.

  11. Complexes of molybdenum(III) with 2-(2'-pyridyl)benzimidazole

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, S P [Patna Univ. (India). Dept. of Chemistry; Prasad, K M [H.D. Jain Coll., Arrah (India). Dept. of Chemistry

    1979-07-01

    Molybdenum(III) forms with 2-(2'-pyridyl) benzimidazole(LH) the trischelated complexes, (Mo(LH)/sub 3/)X/sub 3/ as well as the cationic-anionic complexes, (Mo(LH)/sub 3/X/sub 2/)/sup +/ (Mo(LH)X/sub 4/)/sup -/(X=Cl/sup -/,Br/sup -/ or NCS/sup -/), depending on pH. These complexes have been synthesised and characterised from elemental analyses, i.r. and electronic spectra, magnetic moments and molar conductance.

  12. Convenient synthesis of N,N'-dibenzyl-2,4-diaminopyrimidine-2'-deoxyribonucleoside and 1-methyl-2'-deoxypseudoisocytidine

    CSIR Research Space (South Africa)

    Wellington, Kevin W

    2009-04-01

    Full Text Available The syntheses of N,N'-dibenzyl-2,4-diaminopyrimidine-2'-deoxyribonucleoside and 1-methyl-2'- deoxypseudoisocytidine via Heck coupling are described. A survey of the attempts to use the Heck coupling to synthesize N,N'-dibenzyl-2,4-diaminopyrimidine...

  13. Nonheme Fe(IV) Oxo Complexes of Two New Pentadentate Ligands and Their Hydrogen-Atom and Oxygen-Atom Transfer Reactions.

    Science.gov (United States)

    Mitra, Mainak; Nimir, Hassan; Demeshko, Serhiy; Bhat, Satish S; Malinkin, Sergey O; Haukka, Matti; Lloret-Fillol, Julio; Lisensky, George C; Meyer, Franc; Shteinman, Albert A; Browne, Wesley R; Hrovat, David A; Richmond, Michael G; Costas, Miquel; Nordlander, Ebbe

    2015-08-03

    Two new pentadentate {N5} donor ligands based on the N4Py (N4Py = N,N-bis(2-pyridylmethyl)-N-bis(2-pyridyl)methylamine) framework have been synthesized, viz. [N-(1-methyl-2-benzimidazolyl)methyl-N-(2-pyridyl)methyl-N-(bis-2-pyridyl methyl)amine] (L(1)) and [N-bis(1-methyl-2-benzimidazolyl)methyl-N-(bis-2-pyridylmethyl)amine] (L(2)), where one or two pyridyl arms of N4Py have been replaced by corresponding (N-methyl)benzimidazolyl-containing arms. The complexes [Fe(II)(CH3CN)(L)](2+) (L = L(1) (1); L(2) (2)) were synthesized, and reaction of these ferrous complexes with iodosylbenzene led to the formation of the ferryl complexes [Fe(IV)(O)(L)](2+) (L = L(1) (3); L(2) (4)), which were characterized by UV-vis spectroscopy, high resolution mass spectrometry, and Mössbauer spectroscopy. Complexes 3 and 4 are relatively stable with half-lives at room temperature of 40 h (L = L(1)) and 2.5 h (L = L(2)). The redox potentials of 1 and 2, as well as the visible spectra of 3 and 4, indicate that the ligand field weakens as ligand pyridyl substituents are progressively substituted by (N-methyl)benzimidazolyl moieties. The reactivities of 3 and 4 in hydrogen-atom transfer (HAT) and oxygen-atom transfer (OAT) reactions show that both complexes exhibit enhanced reactivities when compared to the analogous N4Py complex ([Fe(IV)(O)(N4Py)](2+)), and that the normalized HAT rates increase by approximately 1 order of magnitude for each replacement of a pyridyl moiety; i.e., [Fe(IV)(O)(L(2))](2+) exhibits the highest rates. The second-order HAT rate constants can be directly related to the substrate C-H bond dissociation energies. Computational modeling of the HAT reactions indicates that the reaction proceeds via a high spin transition state.

  14. Insertion Chemistry of Cp*2Y(2-pyridyl) and Molecular Structure of the Unexpected CO Insertion Product (Cp*2Y)2(μ-η2 : η2-OC(NC5H4)2)

    NARCIS (Netherlands)

    Deelman, Berth-Jan; Stevels, Willem M.; Teuben, Jan H.; Lakin, Miles T.; Spek, Anthony L.

    1994-01-01

    Pyridine is metalated selectively at the 2-position by (Cp*2YH)2 to yield Cp*2Y(2-pyridyl) (1). Compound 1 reacts with H2 to give the hydride addition product Cp*2Y(NC5H6) (2). With THF and pyridine the adducts Cp*2Y(η2-2-pyridyl)(THF) (3) and Cp*2Y(η1-2-pyridyl)(py) (4) are formed. The pyridine

  15. 6-Methyl-2-pyridyl N-acetyl-1-thio-β-d-glucosa-minide methanol monosolvate.

    Science.gov (United States)

    Chen, Bo; Guo, Miao; Jin, Wei-Hua; Wang, Yan-Wei; Liang, Hong-Ze

    2010-09-15

    In the title compound, C(14)H(20)N(2)O(5)S·CH(4)O, the pyran-ose and pyridine rings are linked through an S atom. The pyran-ose ring has a normal chair conformation. An intra-molecular O-H⋯N hydrogen bond occurs. Inter-molecular O-H⋯O, N-H⋯O, O-H⋯N and weak C-H⋯O hydrogen bonding is present in the crystal structure.

  16. INSERTION CHEMISTRY OF CP-ASTERISK(2)Y(2-PYRIDYL) AND MOLECULAR-STRUCTURE OF THE UNEXPECTED CO INSERTION PRODUCT (CP-ASTERISK(2)Y)2(MU-ETA-2-ETA-2-OC(NC5H4)2)

    NARCIS (Netherlands)

    DEELMAN, BJ; STEVELS, WM; TEUBEN, JH; LAKIN, MT; SPEK, AL

    1994-01-01

    Pyridine is metalated selectively at the 2-position by (Cp*2YH)2 to yield Cp*2Y(2-pyridyl) (1). Compound 1 reacts with H2 to give the hydride addition product Cp*2Y(NC5H6) (2). With THF and pyridine the adducts Cp*2Y(eta2-2-pyridyl)(THF) (3) and Cp*2Y(eta1-2-pyridyl)-(py) (4) are formed. The

  17. catena-Poly[manganese(II-(μ2-3,5-di-2-pyridyl-1,2,4-triazolato-μ2-formato

    Directory of Open Access Journals (Sweden)

    Ya-Wen Zhang

    2008-08-01

    Full Text Available Owing to the presence of crystallographic twofold rotation axes (site symmetry 2, Wyckoff letters e and f, the asymmetric unit of the title compound, [Mn(C12H8N5(CHO2]n, contains one-half of an MnII cation, one-half of a bpt anion (Hbpt is 3,5-di-2-pyridyl-4H-1,2,4-triazole and one-half of a formate anion. The bpt and formate ligands occupy the same C2 symmetry, while the MnII ion resides on another crystallographic twofold rotation axis. Each bpt ligand acts as a cis-bis-chelate to ligate two MnII ions into a one-dimensional chain running along the crystallographic 41 screw axis. Adjacent MnII ions are further bridged by a μ2-formate ligand, completing the distorted octahedral coordination geometry of the cation.

  18. Functional Poly(ε-caprolactone)s via Copolymerization of ε-Caprolactone and Pyridyl Disulfide-Containing Cyclic Carbonate: Controlled Synthesis and Facile Access to Reduction-Sensitive Biodegradable Graft Copolymer Micelles

    NARCIS (Netherlands)

    Chen, Wei; Zou, Yan; Jia, Junna; Meng, Fenghua; Cheng, Ru; Deng, Chao; Feijen, Jan; Zhong, Zhiyuan

    2013-01-01

    Pyridyl disulfide-functionalized cyclic carbonate (PDSC) monomer was obtained in four straightforward steps from 3-methyl-3-oxetanemethanol and exploited for facile preparation of functional poly(ε-caprolactone) (PCL) containing pendant pyridyl disulfide (PDS) groups via ring-opening

  19. Exploration and exploitation of homologous series of bis(acrylamidoalkanes containing pyridyl and phenyl groups: β-sheet versus two-dimensional layers in solid-state photochemical [2 + 2] reactions

    Directory of Open Access Journals (Sweden)

    Mousumi Garai

    2015-09-01

    Full Text Available The homologous series of phenyl and pyridyl substituted bis(acrylamidoalkanes have been synthesized with the aim of systematic analysis of their crystal structures and their solid-state [2 + 2] reactivities. The changes in the crystal structures with respect to a small change in the molecular structure, that is by varying alkyl spacers between acrylamides and/or by varying the end groups (phenyl, 2-pyridyl, 3-pyridyl, 4-pyridyl on the C-terminal of the amide, were analyzed in terms of hydrogen-bonding interference (N—H...Npy versus N—H...O=C and network geometries. In this series, a greater tendency towards the formation of N—H...O hydrogen bonds (β-sheets and two-dimensional networks over N—H...N hydrogen bonds was observed. Among all the structures seven structures were found to have the required alignments of double bonds for the [2 + 2] reaction such that the formations of single dimer, double dimer and polymer are facilitated. However, only four structures were found to exhibit such a solid-state [2 + 2] reaction to form a single dimer and polymers. The two-dimensional hydrogen-bonding layer via N—H...O hydrogen bonds was found to promote solid-state [2 + 2] photo-polymerization in a single-crystal-to-single-crystal manner. Such two-dimensional layers were encountered only when the spacer between acryl amide moieties is butyl. Only four out of the 16 derivatives were found to form hydrates, two each from 2-pyridyl and 4-pyridyl derivatives. The water molecules in these structures govern the hydrogen-bonding networks by the formation of an octameric water cluster and one-dimensional zigzag water chains. The trends in the melting points and densities were also analyzed.

  20. Characterization studies of 1-(4-cyano-2-oxo-1,2-dihydro-1-pyridyl)-3-(4-cyano-1,2-dihydro-1-pyridyl) propane formed from the reaction of hydroxide Ion with 1,3-Bis-(4-cyano pyridinium)propane

    International Nuclear Information System (INIS)

    Fiori, Simone; Schuquel, Ivania T.A.; Meyer, Emerson; Hioka, Noboru; Silva, Idelcio N. da; Politi, Mario J.; Catalani, Luiz H.; Chaimovich, Hernan

    2011-01-01

    The aqueous alkaline reaction of 1,3.bis(4.cyanopyridinium)propane dibromide, a reactant constituted of two pyridinium rings linked by a three.methylene bridge, generates a novel compound, 1-(4-cyano-2-oxo-1,2-dihydro-1-pyridyl)-3-(4-cyano-1,2-dihydro-1-pyridyl) propane. The reaction pathway is attributed to the proximity of the OH. ion inserted between two pyridinium moieties, which occurs only in bis(pyridinium) derivatives connected by short methylene spacers, where charge-conformational effects are important. (author)

  1. Polymerization of Methyl Methacrylate Catalyzed by Co(II), Cu(II), and Zn(II) Complexes Bearing N-Methyl-N-((pyridin-2-yl)methyl) cyclohexanamine

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Seoung Hyun; Lee, Hyosun [Kyungpook National University, Daegu (Korea, Republic of); Shin, Jongwon [POSTECH, Pohang (Korea, Republic of); Nayab, Saira [Shaheed Benazir Bhutto University, Sheringal (Pakistan)

    2016-05-15

    We demonstrated the synthesis and characterization of Co(II), Cu(II), and Zn(II) complexes ligated to N-methyl-N-((pyridin-2-yl)methyl)cyclohexanamine. The complex [Co(nmpc)Cl{sub 2}] in the presence of MMAO showed the highest catalytic activity for MMA polymerization at 60 °C compared with its Zn(II) and Cu(II) analogs. The metal center showed an obvious influence on the catalytic activity, although this appeared to have no effect on the stereo-regularity of the resultant PMMA. X-ray diffraction analysis revealed that [Co(nmpc)Cl{sub 2}] and [Zn(nmpc)Cl{sub 2}] crystallized in the monoclinic system with space group P2{sub 1}/c and existed as monomeric and solvent-free complexes.

  2. On the relationship between corrosion inhibiting effect and molecular structure of 2,5-bis(n-pyridyl)-1,3,4-thiadiazole derivatives in acidic media: Ac impedance and DFT studies

    Energy Technology Data Exchange (ETDEWEB)

    Bentiss, F., E-mail: fbentiss@enscl.f [Laboratoire de Chimie de Coordination et d' Analytique (LCCA), Faculte des Sciences, Universite Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco); Mernari, B. [Laboratoire de Chimie de Coordination et d' Analytique (LCCA), Faculte des Sciences, Universite Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco); Traisnel, M. [Unite Materiaux et Transformations (UMET), Ingenierie des Systemes Polymeres, CNRS UMR 8207, ENSCL, B.P. 90108, F-59652 Villeneuve d' Ascq Cedex (France); Vezin, H. [Laboratoire de Spectrochimie Infrarouge et Raman (LASIR), UMR-CNRS 8516, Universite des Sciences et Technologies de Lille, Batiment C5, F-59655 Villeneuve d' Ascq Cedex (France); Lagrenee, M., E-mail: michel.lagrenee@ensc-lille.f [Unite de Catalyse et de Chimie du Solide (UCCS), UMR-CNRS 8181, ENSCL, B.P. 90108, F-59652 Villeneuve d' Ascq Cedex (France)

    2011-01-15

    Research highlights: {yields}2,5-Bis(n-pyridyl)-1,3,4-thiadiazoles (n-PTH) act as good inhibitors for the mild steel in acidic media. {yields}The inhibiting protection depends on the position of the nitrogen on the pyridinium substituent according to order 3-PTH > 2-PTH > 4-PTH. {yields}The adsorption of n-PTH is found to follow the Langmuir's adsorption isotherm. {yields}Data obtained from quantum chemical calculations using DFT method were correlated to the experimentally obtained inhibition efficiencies. - Abstract: The inhibition properties of 2,5-bis(n-pyridyl)-1,3,4-thiadiazoles (n-PTH) on corrosion of mild steel in different acidic media (1 M HCl, 0.5 M H{sub 2}SO{sub 4} and 1 M HClO{sub 4}) were analyzed by electrochemical impedance spectroscopy (EIS). The n-PTH derivatives exhibit good inhibition properties in different acidic solutions and the calculated values of {Delta}G{sub ads}{sup 0} revealed that the adsorption mechanism of n-PTH on steel surface is mainly due to chemisorption. While in 1 M HClO{sub 4}, both 2-PTH and 4-PTH isomers stimulate the corrosion process especially at low concentrations. Quantum chemical calculations using the density functional theory (DFT) were performed on n-PTH derivatives to determine the relationship between molecular structure and their inhibition efficiencies. The results of the quantum chemical calculations and experimental inhibition efficiency were subjected to correlation analysis and indicate that the inhibition effects of n-PTH may be explained in terms of electronic properties.

  3. Spectrofluorimetric determination of gallium with N-(3-hydroxy-2-pyridyl) salicrystaldimine and its application to the analysis of biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Rojas, F.; Cano Pavon, J.M. [Department of Analytical Chemistry, Faculty of Science, University of Malaga, Malaga (Spain)

    1995-12-31

    The fluorimetric determination of gallium at the nanogram level, based on the formation of a fluorescent complex between Ga(III) and N-(3-hydroxy-2-pyridyl) salicylaldimine (3-OH-PSA), is purposed. With excitation at 397 nm, the chelate has a maximum emission at 498 nm. The reaction is carried out at acidic pH in aqueous-DMF medium (40% v/v DMF). The influence of the reaction variables are discussed. The detection limit is 0.9 ng ml``-1 and the range of application is 1-125 ng ml``-1. The relative error of the methods is + - 1.6%. The proposed method has been applied to the determination of gallium in biological sample. (Author) 12 refs.

  4. Fabrication of a PVC membrane samarium(III) sensor based on N,N Prime ,N Double-Prime -tris(4-pyridyl)trimesic amide as a selectophore

    Energy Technology Data Exchange (ETDEWEB)

    Zamani, Hassan Ali, E-mail: haszamani@yahoo.com [Department of Applied Chemistry, Mashhad Branch, Islamic Azad University, Mashhad (Iran, Islamic Republic of); Naghavi-Reyabbi, Fatemeh [Resident of General Surgery, Endoscopic and Minimaly Invasive Surgery Research Center, Ghaem Hospital, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad (Iran, Islamic Republic of); Faridbod, Farnoush [Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran (Iran, Islamic Republic of); Mohammadhosseini, Majid [Department of Chemistry, Faculty of Basic Sciences, Shahrood Branch, Islamic Azad University, Shahrood (Iran, Islamic Republic of); Ganjali, Mohammad Reza [Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran (Iran, Islamic Republic of); Tadjarodi, Azadeh; Rad, Maryam [Department of Chemistry, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of)

    2013-03-01

    A new ion-selective electrode for Sm{sup 3+} ion is described based on the incorporation of N,N Prime ,N Double-Prime -tris(4-pyridyl)trimesic amide (TPTA) in a poly(vinylchloride) (PVC) matrix. The membrane sensor comprises nitrobenzene (NB) as a plasticizer, and oleic acid (OA) as an anionic additive. The sensor with the optimized composition shows a Nernstian potential response of 19.8 {+-} 0.5 mV decade{sup -1} over a wide concentration range of 1.0 Multiplication-Sign 10{sup -2} and 1 Multiplication-Sign 10{sup -6} mol L{sup -1}, with a lower detection limit of 4.7 Multiplication-Sign 10{sup -7} mol L{sup -1} and satisfactor applicable pH range of 3.6-9.2. Having a short response time of less than 10 s and a very good selectivity towards the Sm{sup 3+} over a wide variety of interfering cations (e.g. alkali, alkaline earth, transition and heavy metal ions) the sensor seemed to be a promising analytical tool for determination of the Sm{sup 3+}. Hence, it was used as an indicator electrode in the potentiometric titration of samarium ion with EDTA. It was also applied to the direct samarium recovery in binary mixtures. - Highlights: Black-Right-Pointing-Pointer A new Sm{sup 3+}-PVC membrane sensor is introduced for determination of Sm{sup 3+} ions in the solutions. Black-Right-Pointing-Pointer N,N Prime ,N Double-Prime -tris(4-pyridyl)trimesic amide was used as a suitable selectophore for samarium sensor. Black-Right-Pointing-Pointer Detection limit of the sensor is 4.7 Multiplication-Sign 10{sup -7} mol L{sup -1} with a short response time of less than 10 s.

  5. Symmetric bi-pyridyl banana-shaped molecule and its intermolecular hydrogen bonding liquid-crystalline complexes

    Science.gov (United States)

    Sui, Dan; Hou, Qiufei; Chai, Jia; Ye, Ling; Zhao, Liyan; Li, Min; Jiang, Shimei

    2008-11-01

    A new symmetric bi-pyridyl banana-shaped molecule 1,3-phenylene diisonicotinate (PDI) was designed and synthesized. Its molecular structure was confirmed by FTIR, Elemental analysis and 1H NMR. X-ray crystallographic study reveals that there is an angle of approximate 118° among the centroids of the three rings (pyridyl-phenyl-pyridyl) in each PDI molecule indicating a desired banana shape. In addition, a series of liquid crystal complexes nBA:PDI:nBA induced by intermolecular hydrogen bonding between PDI (proton acceptor) and 4-alkoxybenzoic acids (nBA, proton donor) were synthesized and characterized. The mesomorphism properties and optical textures of the complex of nBA:PDI:nBA were investigated by differential scanning calorimetry, polarizing optical microscope and X-ray diffraction.

  6. 6-Methyl-2-pyridyl N-acetyl-1-thio-β-d-glucosa­minide methanol monosolvate

    Science.gov (United States)

    Chen, Bo; Guo, Miao; Jin, Wei-Hua; Wang, Yan-Wei; Liang, Hong-Ze

    2010-01-01

    In the title compound, C14H20N2O5S·CH4O, the pyran­ose and pyridine rings are linked through an S atom. The pyran­ose ring has a normal chair conformation. An intra­molecular O—H⋯N hydrogen bond occurs. Inter­molecular O—H⋯O, N—H⋯O, O—H⋯N and weak C—H⋯O hydrogen bonding is present in the crystal structure. PMID:21587547

  7. Enhancement of oxygen reduction at Fe tetrapyridyl porphyrin by pyridyl-N coordination to transition metal ions

    International Nuclear Information System (INIS)

    Maruyama, Jun; Baier, Claudia; Wolfschmidt, Holger; Bele, Petra; Stimming, Ulrich

    2012-01-01

    One of the promising candidates as noble-metal-free electrode catalysts for polymer electrolyte fuel cells (PEFCs) is a carbon material with nitrogen atoms coordinating iron ions embedded on the surface (Fe-N x moiety) as the active site, although the activity is insufficient compared to conventional platinum-based electrocatalysts. In order to obtain fundamental information on the activity enhancement, a simple model of the Fe-N x active site was formed by adsorbing 5,10,15,20-Tetrakis(4-pyridyl)-21H,23H-porphine iron(III) chloride (FeTPyPCl) on the basal plane of highly oriented pyrolytic graphite (HOPG), and cathodic oxygen reduction was investigated on the surface in 0.1 M HClO 4 . The catalytic activity for oxygen reduction was enhanced by loading transition metal ions (Co 2+ , Ni 2+ , Cu 2+ ) together with FeTPyPCl. The X-ray photoelectron spectrum of the surface suggested that the metal was coordinated by the pyridine-N. The enhancement effect of the transition metals was supported by two different measurements: oxygen reduction at HOPG in 0.1 M HClO 4 dissolving FeTPyPCl and the metal ions; oxygen reduction in 0.1 M HClO 4 at the subsequently well-rinsed and dried HOPG. The ultraviolet–visible spectrum for the solution also suggested the coordination between the pyridyl-N and the metal ions. The oxygen reduction enhancement was attributed to the electronic interaction between the additional transition metal and the Fe center of the porphyrin through the coordination bonds. These results implied that the improvement of the activity of the noble-metal-free catalyst would be possible by the proper introduction of the transition metal ions around the active site.

  8. Characterization of the radioactive metabolites of the 5-HT1A receptor radioligand, [O-methyl-C-11]WAY-100635, in monkey and human plasma by HPLC : Comparison of the behaviour of an identified radioactive metabolite with parent radioligand in monkey using PET

    NARCIS (Netherlands)

    Osman, S; Lundkvist, C; Pike, VW; Halldin, C; McCarron, JA; Swahn, CG; Ginovart, N; Luthra, SK; Bench, CJ; Grasby, PM; Wikstrom, H; Barf, T; Cliffe, IA; Fletcher, A; Farde, L

    N-(2-(4-(2-Methoxy-phenyl)-1-piperazin-1-yl)ethyl)-N-(2-pyridyl)cyclohexanecarboxamide (WAY-100635), labelled in the O-methyl group with carbon-11 (t(1/2) = 20.4 min), is a promising radioligand for application with positron emission tomography (PET) to the study of 5-HT1A receptors in living human

  9. Isobaric (vapour + liquid) equilibrium for N-methyl-2-pyrrolidone with branched alcohols

    International Nuclear Information System (INIS)

    Gnanakumari, P.; Venkatesu, P.; Hsieh, C.-T.; Rao, M.V. Prabhakara; Lee, M.-J.; Lin, Ho-mu

    2009-01-01

    The (vapour + liquid) equilibrium (VLE) and boiling temperature measurements have been determined at 95.3 kPa as a function of composition for the binary liquid mixtures of N-methyl-2-pyrrolidone (NMP) with branched alcohols using a Swietoslawski-ebulliometer. The branched alcohols include 2-propanol, 2-butanol, 2-methyl-l- propanol, 2-methyl-2-propanol, and 3-methyl-l-butanol. The experimental temperature-composition (T-x) results were used to estimate Wilson parameters and then used to calculate the equilibrium vapour compositions and the excess Gibbs free energy at T = 298.15 K. The experimental temperature-composition (T, x) results were correlated with the Wilson, the NRTL and the UNIQUAC models. The experimental results are interpreted in terms of intermolecular interactions between constituent molecules

  10. Formation of O2-methylthymine in poly(dA-dT) on methylation with N-methyl-N-nitrosourea and dimethyl sulphate. Evidence that O2-methylthymine does not miscode during DNA synthesis.

    Science.gov (United States)

    Saffhill, R; Abbott, P J

    1978-01-01

    The alternating co-polymer has been methylated with either N methyl-N-nitrosourea (MNU) or dimethyl sulphate (DMS) and the levels of the various methylated thymidines (O2-methylthymidine, 3-methylthymidine and O4-methylthymidine) measured. MNU produced all three compounds whereas DMS only produced 3-methylthymidine and O2-methylthymidine at detectable levels. These results have been combined with our earlier results concerning the misincorporation of dGMP with E. coli DNA polymerase using MNU-methylated poly(dA-dT). These results indicate that O2-methylthymidine does not miscode during DNA synthesis. PMID:353735

  11. Reaction products from N-methyl-N-nitrosourea and deoxyribonucleic acid containing thymidine residues. Synthesis and identification of a new methylation product, O4-methyl-thymidine

    Science.gov (United States)

    Lawley, P. D.; Orr, D. J.; Shah, S. A.; Farmer, P. B.; Jarman, M.

    1973-01-01

    1. DNA was treated with N-methyl-N-nitrosourea at pH7–8, 37°C, degraded to yield 3- and 7-methylpurines and deoxyribonucleosides and the reaction products were separated by chromatography on ion-exchange resins. The following methods for identification and determination of products were used: with unlabelled N-methyl-N-nitrosourea, u.v. absorption; use of methyl-14C-labelled N-methyl-N-nitrosourea and use of [14C]thymine-labelled DNA. 2. The synthesis of O4-methylthymidine and its identification by u.v. and mass spectroscopy are reported. 3. 3-Methylthymidine and O4-methylthymidine were found as methylation products from N-methyl-N-nitrosourea with thymidine and with DNA, in relatively small yields. Unidentified products containing thymine were found in enzymic digests of N-methyl-N-nitrosourea-treated DNA, which may be phosphotriesters. 4. The possible role of formation of methylthymines in mutagenesis by N-methyl-N-nitrosourea is discussed. PMID:4798180

  12. Synthesis of racemic [methyl-d3]-labeled cis- and trans-3'-hydroxycotinine

    International Nuclear Information System (INIS)

    Ravard, A.; Crooks, P.A.

    1994-01-01

    A method is described for the synthesis of the racemic [methyl-d 3 ] forms of the nicotine metabolites cis-3'-hydroxycotinine and trans-3'-hydroxycotinine. The key intermediate was [methyl-d 3 ]-N-methylhydroxylamine, obtained from a selective hydrogenation of d 3 -nitro-methane. This intermediate was converted to [methyl-d 3 ]-α-3-pyridyl-N-methylnitrone, which was condensed with methyl acrylate to give a mixture of isomeric isoxazolidines. The hydrogenolysis of this mixture afforded a 70:30 mixture of [methyl-d 3 ] cis- and trans-3'-hydroxycotinine, from which the pure cis-isomer could be isolated by recrystallization from acetone. [Methyl-d 3 ]-trans-3'-hydroxycotinine could be prepared in high yield from the cis-isomer via chiral inversion utilizing a Mitsunobu reaction, or by chromatographic separation from a mixture of the cis- and trans-3'-benzoyloxycotinine, followed by O-debenzoylation in methanolic NaOH. (author)

  13. Biochemical and physiological responses of lycoris sprengeri bulblets (amaryllidaceae) to exogenously applied N-(2-Chloro-4-Pyridyl)-N1-Phenylurea (CPPU)

    International Nuclear Information System (INIS)

    Ren, Z.; Xia, Y.; Xiao, Y.; Zhang, D.; Lv, X.

    2017-01-01

    Bulblets of Lycoris sprengeri (Amaryllidaceae) were obtained by cutting. Six concentrations of N-(2-chloro-4-pyridyl)-N1-phenylurea (CPPU) solutions were sprayed on leaves from one-year-old bulblets during their green period. Fresh weight, diameter,carbohydrate content, activity of starch metabolism-related enzymes and levels of endogenous hormones of bulblets were determined. The effects of CPPU treatment on bulblet development and biochemical and physiological indices of L. sprengeri were analyzed using the determined values. The results showed that CPPU treatment at an appropriate concentration promoted the enlargement of L. sprengeri bulblets; the optimal concentration was 7.5 mg L-1. Bulblet growth showed a significant positive correlation with starch content and the activities of soluble starch synthase (SSS) and starch-bound starch synthase (GBSS). Bulblet growth showed anextremely significant positive correlation with the ratio of endogenous gibberellic acid/abscisic acid (GA/ABA). The GA/ABA ratio showed a significant positive correlation with the activities of (a+beta)-amylase and GBSS. The exogenous application of CPPU promoted the synthesis and accumulation of starch in the bulblets of L. sprengeri and the activities of starch metabolism-related enzymes; an increase in the endogenous GA/ABA ratio had a synergistic effect. (author)

  14. Dibromido(6-methyl-2,2′-bipyridine-κ2N,N′zinc(II

    Directory of Open Access Journals (Sweden)

    Vahid Amani

    2010-10-01

    Full Text Available In the title compound, [ZnBr2(C11H10N2], the ZnII atom is four-coordinated in a distorted tetrahedral configuration by two N atoms from a 6-methyl-2,2′-bipyridine ligand and two terminal Br atoms. Weak intermolecular C—H...Br hydrogen bonds and π–π stacking interactions between the pyridine rings [centroid–centroid distances = 3.763 (5 and 3.835 (6 Å] contribute to crystal-packing effects.

  15. Studies with β-Oxoalkanonitriles: Simple Novel Synthesis of 3-[2,6-Diaryl-4- pyridyl]-3-oxopropanenitriles

    Directory of Open Access Journals (Sweden)

    Sayed M. Riyadh

    2008-12-01

    Full Text Available Heteroaromatization of ethyl 2-cyano-4-oxo-2-(2-oxo-2-arylethyl-4-arylbutanoates 3a,b with ammonium acetate gave ethyl 2,6-diarylisonicotinates 4a,b. Treatment of the latter with acetonitrile afforded novel β-oxoalkanonitriles 6a,b. Reactions of 6a,b with phenyl hydrazine and hydroxylamine gave the corresponding pyridyl aminopyrazoles 8a,b and pyridyl aminoisoxazoles 10a,b, respectively.

  16. Straightforward Synthesis of N-Methyl-4-(pinB-2(3H-benzothiazol-2-one: A Promising Cross-Coupling Reagent

    Directory of Open Access Journals (Sweden)

    Shotaro Izawa

    2018-01-01

    Full Text Available Cyclo-condensation of N-methyl-2-bromoaniline with chlorocarbonylsulfenyl chloride (CCSC promoted by PhNMe2 and AlCl3, afforded N-methyl-2-bromo-2(3H-benzothiazol-2-one in good yield. Miyaura–Ishiyama cross-coupling of this brominated 2(3H-benzothiazol-2-one with bis(pinacolatodiborone [(pin2B2] produced a novel N-methyl-4-(pinB-2(3H-benzothiazol-2-one (3 using (pin2B2 in the presence of the PdCl2(PPh32 catalyst. The obtained 4-(pinB compound is regarded as a new entry for the library of Suzuki–Miyaura cross-coupling reactions.

  17. Crystal structure of (4,4′-bipyridyl-κNbis[N-(2-hydroxyethyl-N-isopropyldithiocarbamato-κ2S,S′]zinc(II–4,4′-bipyridyl (2/1 and its isostructural cadmium(II analogue

    Directory of Open Access Journals (Sweden)

    Yee Seng Tan

    2017-11-01

    Full Text Available The title structures, [M(C6H12NOS22(C10H8N2]·0.5C10H8N2, for M = Zn, (I, and Cd, (II, feature terminally bound 4,4′-bipyridyl ligands and non-coordinating 4,4′-bipyridyl molecules, with the latter disposed about a centre of inversion. The coordination geometry about the metal atom is defined by two non-symmetrically chelating dithiocarbamate ligands and a pyridyl N atom. The NS4 donor sets are distorted but, approximate to trigonal bipyramidal in each case. In the crystal, hydroxy-O—H...O(hydroxy and hydroxy-O—H...N(pyridyl hydrogen bonds between the zinc-containing molecules lead to a supramolecular layer parallel to (100. The three-dimensional architecture arises as the layers are linked via methine-C—H...S, pyridyl-C—H...O(hydroxy and π–π [inter-centroid distance between coordinated pyridyl rings = 3.6246 (18 Å] interactions. Channels along the c-axis direction are occupied by the non-coordinating 4,4′-bipyridine molecules, which are held in place by C—H...π(chelate ring contacts.

  18. A tetrakis(amido)phosphonium cation containing 2-pyridyl ( Py ...

    Indian Academy of Sciences (India)

    less basic reagents in these reactions did not lead to any deprotonation which .... the crystal of 1·NO3 which unequivocally supports its existence in the .... by the pyridyl amino segments may have played a vital role in neutralizing the internal ...

  19. Methylation of ribonucleic acid by the carcinogens dimethyl sulphate, N-methyl-N-nitrosourea and N-methyl-N′-nitro-N-nitrosoguanidine. Comparisons of chemical analyses at the nucleoside and base levels

    Science.gov (United States)

    Lawley, P. D.; Shah, S. A.

    1972-01-01

    1. The following methods for hydrolysis of methyl-14C-labelled RNA, and for chromatographic isolation and determination of the products, were investigated: enzymic digestion to nucleosides at pH6 or 8; alkaline hydrolysis and conversion into nucleosides; hydrolysis by acid to pyrimidine nucleotides and purine bases, or completely to bases; chromatography on Dowex 50 (NH4+ form) at pH6 or 8.9, or on Dowex 50 (H+ form), or on Sephadex G-10. 2. The suitability of the various methods for determination of methylation products was assessed. The principal product, 7-methylguanosine, was unstable under the conditions used for determinations of nucleosides. 3- and 7-Methyladenine and 3- and 7-methylguanine are best determined as bases; 1-methyladenine and 3-methylcytosine can be isolated as either nucleosides or bases; O6-methylguanine is unstable under the acid hydrolysis conditions used and can be determined as the nucleoside; 3-methyluracil was detected, but may be derived from methylation of the ionized form of uracil. 3. Differences between the patterns of methylation of RNA and homopolyribonucleotides by the N-methyl-N-nitroso compounds and dimethyl sulphate were found: the nitroso compounds were able to methylate O-6 of guanine, were relatively more reactive at N-7 of adenine and probably at N-3 of guanine, but less reactive at N-1 of adenine, N-3 of cytosine and probably at N-3 of uridine. They probably reacted more with the ribose–phosphate chain, but no products from this were identified. 4. The possible influences of these differences on biological action of the methylating agents is discussed. Nitroso compounds may differ principally in their ability to induce miscoding in the Watson–Crick sense by reaction at O-6 of guanine. Both types of agent may induce miscoding to a lesser extent through methylation at N-3 of guanine; both can methylate N atoms, presumably preventing Watson–Crick hydrogen-bonding. N-Methyl-N-nitrosourea can degrade RNA, possibly

  20. Inhibition of protein synthesis by N-methyl-N-nitrosourea in vivo

    Science.gov (United States)

    Kleihues, P.; Magee, P. N.

    1973-01-01

    1. The intraperitoneal injection of N-methyl-N-nitrosourea (100mg/kg) caused a partial inhibition of protein synthesis in several organs of the rat, the maximum effect occurring after 2–3h. 2. In the liver the inhibition of protein synthesis was paralleled by a marked disaggregation of polyribosomes and an increase in ribosome monomers and ribosomal subunits. No significant breakdown of polyribosomes was found in adult rat brains although N-methyl-N-nitrosourea inhibited cerebral and hepatic protein synthesis to a similar extent. In weanling rats N-methyl-N-nitrosourea caused a shift in the cerebral polyribosome profile similar to but less marked than that in rat liver. 3. Reaction of polyribosomal RNA with N-[14C]methyl-N-nitrosourea in vitro did not lead to a disaggregation of polyribosomes although the amounts of 7-methylguanine produced were up to twenty times higher than those found after administration of sublethal doses in vivo. 4. It was concluded that changes in the polyribosome profile induced by N-methyl-N-nitrosourea may reflect the mechanism of inhibition of protein synthesis rather than being a direct consequence of the methylation of polyribosomal mRNA. PMID:4774397

  1. N-heterocyclic carbene copper(I) catalysed N-methylation of amines using CO2

    KAUST Repository

    Santoro, Orlando

    2015-09-30

    The N-methylation of amines using CO2 and PhSiH3 as source of CH3 was efficiently performed using a N-heterocyclic carbene copper(I) complex. The methodology was found compatible with aromatic and aliphatic primary and secondary amines. Synthetic and computational studies have been carried out to support the proposed reaction mechanism for this transformation.

  2. N-heterocyclic carbene copper(I) catalysed N-methylation of amines using CO2

    KAUST Repository

    Santoro, Orlando; Lazreg, Faï ma; Minenkov, Yury; Cavallo, Luigi; Cazin, Catherine S. J.

    2015-01-01

    The N-methylation of amines using CO2 and PhSiH3 as source of CH3 was efficiently performed using a N-heterocyclic carbene copper(I) complex. The methodology was found compatible with aromatic and aliphatic primary and secondary amines. Synthetic and computational studies have been carried out to support the proposed reaction mechanism for this transformation.

  3. THE EFFECTS OF N-2-HYDROXYETHYL-N-METHYL-P-TOLUIDINE ON METHYL METHACRYLATE RADICAL POLYMERIZATION AND ACRYLONITRILE PHOTOINDUCED POLYMERIZATION

    Institute of Scientific and Technical Information of China (English)

    QIU Kunyuan; ZHANG Zhanghua; FENG Xinde

    1992-01-01

    The effects of N-2-hydroxyethyl-N-methyl-p-toluidine (HMT) on MMA polymerization using organic peroxide as an initiator and on AN photoinduced polymerization have been investigated respectively. The kinetics of polymerization and the overall activation energy of polymerization were determined. Based on kinetics study and the end group analysis of the polymer obtained by UV spectrum method, the initiation mechanism is proposed.

  4. Reduction of 2-chloro-N-phenylpropanamide and 2-methyl-N-phenylaziridine with lithium aluminium hydride

    DEFF Research Database (Denmark)

    Vilhelmsen, Mie Højer; Østergaard, Lars Frøsig; Nielsen, Mogens Brøndsted

    2008-01-01

    in the reduction and can be isolated from reactions with less LiAlH4. Reduction of 2-methyl-N-phenylaziridine itself proceeds non-regioselectively to provide a mixture of propyl- and isopropylanilines. Formation of the amines by reduction of the aziridine is much slower than formation by reduction of the 2......-chloropropanamide, which indicates that Lewis acid catalysis (by aluminium chlorohydrides) facilitates the reduction of the aziridine. In addition, Lewis acid catalysis increases the relative yield of the propylamine product. The reduction of 2-chloro-N-phenylpropanamide furnishes 2-phenylamino-1-propanol as a by...

  5. Theoretical and Experimental Investigation of Pyridyl thiourea Derivatives As Ionophores For Cu(II) Ion Detection

    International Nuclear Information System (INIS)

    Wan Mohd Khairul; Mohd Faizuddin Abu Hasan; Adibah Izzati Daud; Adibah Izzati Daud; Hafiza Mohamed Zuki; Ku Halim Ku Bulat; Maisara Abdul Kadir

    2016-01-01

    Copper (II) ion chemical sensors based on pyridine-thiourea derivatives; N-pyridyl-N ' -(biphenyl-4-carbonyl)thiourea (L1), and N-pyridyl-N ' -(3,5-dimethy oxybenzoyl)thiourea (L2) were synthesised, characterised, and studied as ionophores in the form of thin-films PVC membranes. The ionophores exhibited good responses towards copper (II) ion over the concentration range of 2 x 10 -4 to 10 x 10 -4 M with a limit of detection 1.34 x 10 -5 to 1.48 x 10 -5 M. The proposed sensors L1 and L2 revealed good performance in term of reproducibility and regeneration of the ionophores with low relative standard deviation (RSD) values 4.17 % and 2.74 % respectively. Besides, quantum chemical calculation performed using Gaussian 09 program indicated the oxygen (O) atom from carbonyl moiety (C=O) was the most favourite reactive site and mainly responsible for ionophore Cu(II) interaction. The obtained data revealed pyridine-thiourea derivatives offered great potential as ionophore for the detection of Cu (II) ion. (author)

  6. Crystal structure of bis[2,5-bis(pyridin-2-yl-1,3,4-thiadiazole-κ2N2,N3]bis(thiocyanato-κScopper(II

    Directory of Open Access Journals (Sweden)

    Abdelhakim Laachir

    2016-08-01

    Full Text Available The mononuclear title complex, [Cu(SCN2(C12H8N4S2], was obtained by the reaction of 2,5-bis(pyridin-2-yl-1,3,4-thiadiazole and potassium thiocyanate with copper(II chloride dihydrate. The copper cation lies on an inversion centre and displays an elongated octahedral coordination geometry. The equatorial positions are occupied by the N atoms of two 2,5-bis(pyridin-2-yl-1,3,4-thiadiazole ligands, whereas the axial positions are occupied by the S atoms of two thiocyanate anions. The thiadiazole and the pyridyl rings linked to the metal are approximately coplanar, with a maximum deviation from the mean plane of 0.190 (2 Å. The cohesion of the crystal structure is ensured by weak C—H...N hydrogen bonds and π–π interactions between parallel pyridyl rings of neighbouring molecules [centroid-to-centroid distance = 3.663 (2 Å], leading to a three-dimensional network.

  7. [6-chloro-3-pyridylmethyl-3H]neonicotinoids as high-affinity radioligands for the nicotinic acetylcholine receptor: preparation using NaB3H4 and LiB3H4

    International Nuclear Information System (INIS)

    Latli, Bachir; Casida, J.E.

    1996-01-01

    NaB 3 H 4 and LiB 3 H 4 at 78% and 97% isotopic enrichments, respectively, were used in the synthesis of 3 H-labeled 1-(6-chloro-3-pyridyl)-methyl-2-nitromethyleneimidazolidine (CH-IMI) and N'-[(6-chloro-3-pyridyl)methyl]-n''-cyano-n'-methylacetamidine (acetamiprid) (two very potent insecticides) and of 1-(6-chloro-3-pyridyl)methyl-2-iminoimidazolidine (desnitro-IMI) (a metabolite of the commercial insecticides imidacloprid). 6-Chloronicotinoyl chloride was treated with either NaB 3 H 4 in methanol or LiB 3 H 4 in tetrahydrofuran and the resulting alcohol transformed to 2-chloro-5-chloromethylpyridine, which was then coupled to N-cyano-N'-methylacetamidine to give [ 3 H] acetamiprid (45 Ci/mmol). 2-Chloro-5-chloro[ 3 H]methylpyridine was also reacted with ethylenediamine and the product was either refluxed in absolute ethanol with 1,1-bis(methylthio)-2-nitro-ethylene to provide [ 3 H]CH-IMI or reacted in toluene with a solution of cyanogen bromide to produce [ 3 H] desnitro-IMI (each 55 Ci/mmol. (author)

  8. Iron(II) complexes of new hexadentate 1,1,1-tris-(iminomethyl)ethane podands, and their 7-methyl-1,3,5-triazaadamantane rearrangement products.

    Science.gov (United States)

    Diener, Sara A; Santoro, Amedeo; Kilner, Colin A; Loughrey, Jonathan J; Halcrow, Malcolm A

    2012-04-07

    New iron(II) podand complexes have been prepared, by condensation of 2-(aminomethyl)-2-methyl-1,3-diaminopropane with 3 equiv of a heterocyclic aldehyde in the presence of hydrated Fe[BF(4)](2) or Fe[ClO(4)](2) as templates. The 2-(aminomethyl)-2-methyl-1,3-diaminopropane is prepared in situ by deprotonation of its trihydrochloride salt. The chloride must be removed from these reactions by precipitation with silver, to avoid the formation of the alternative 2,4,6-trisubstituted-7-methyl-1,3,5-triazaadamantane condensation products, or their FeCl(2) adducts. The crystal structures of two 2,4,6-tri(pyridyl)-7-methyl-1,3,5-triazaadamantane-containing species are presented, and contain two different geometric isomers of this tricyclic ring with three equatorial, or two equatorial and one axial, pyridyl substituents. Both structures feature strong C-HX (X = Cl or F) hydrogen bonding from the aminal C-H groups in the triazaadamantane ring. Five iron(II) podand complexes were successfully obtained, all of which contain low-spin iron centres.

  9. N-[11C]methyl-3,4-methylenedioxyamphetamine (Ecstasy) and 2-methyl-N-[11C]methyl-4,5-methylenedioxyamphetamine. Synthesis and biodistribution studies

    International Nuclear Information System (INIS)

    Patt, M.; Machulla, H.J.; Guendisch, D.; Kovar, K.A.; Wuellner, U.; Blocher, A.

    1999-01-01

    In order to evaluate the neurobiological mechanism causing the psychogenic effects of methylenedioxy-derivatives of amphetamine, the carbon-11 labeled analogues of 3,4-methylenedioxymethamphetamine (MDMA), 2 and 2,N-dimethyl-4,5-methylenedioxyamphetamine (MADAM-6) 4 were prepared for application in in-vivo PET studies by methylation of 3,4-methylenedioxyamphetamine (MDA) 1 and 2-methyl-4,5-methylenedioxyamphetamine 3 with [ 11 C]CH 3 I. The radiochemical yield was determined in dependence on time, temperature and amount of precursor. The best conditions for a fast labeling reaction with carbon-11 on a preparative scale were found to be a reaction time of 10 min using 1 mg of the corresponding dimethyl-precursors 1 or 3, thus obtaining radiochemical yields of 60% (based on produced [ 11 C]CH 3 I). Biodistribution studies were performed in rats, a high brain to blood ratio of 7.5 was observed for [ 11 C]MDMA in contrast to a ratio of 3.7 for [ 11 C]MADAM-6. (author)

  10. A Bis-Triazacyclononane Tris-Pyridyl N9 -Azacryptand "Beer Can" Receptor for Complexation of Alkali Metal and Lead(II) Cations.

    Science.gov (United States)

    Brown, Asha; Bunchuay, Thanthapatra; Crane, Christopher G; White, Nicholas G; Thompson, Amber L; Beer, Paul D

    2018-04-18

    A new bis-triazacyclononane tris-pyridyl N 9 -azacryptand ligand is prepared via a convenient one-pot [2+3] condensation reaction between triazacyclononane and 2,6-bis(bromomethyl) pyridine in the presence of M 2 CO 3 (M=Li, Na, K). The proton, lithium, sodium, potassium and lead(II) complexes of the ligand are characterised in the solid state. Preliminary solution-phase competition experiments indicate that the cryptand ligand preferentially binds lead(II) in the presence of sodium, calcium, potassium and zinc cations in methanol solution. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. 40 CFR 721.1000 - Benzenamine, 3-chloro-2,6-dinitro-N,N-dipropyl-4-(tri-fluoro-methyl)-.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Benzenamine, 3-chloro-2,6-dinitro-N,N-dipropyl-4-(tri-fluoro-methyl)-. 721.1000 Section 721.1000 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.1000 Benzenamine, 3-chloro-2,6-dinitro-N,N...

  12. N,N'-(Hexane-1,6-diylbis(4-methyl-N-(oxiran-2-ylmethylbenzenesulfonamide: Synthesis via cyclodextrin mediated N-alkylation in aqueous solution and further Prilezhaev epoxidation

    Directory of Open Access Journals (Sweden)

    Julian Fischer

    2013-12-01

    Full Text Available N-alkylation of N,N'-(hexane-1,6-diylbis(4-methylbenzenesulfonamide with allyl bromide and subsequent Prilezhaev reaction with m-chloroperbenzoic acid to give N,N'-(hexane-1,6-diylbis(4-methyl-N-(oxiran-2-ylmethylbenzenesulfonamide is described. This twofold alkylation was performed in aqueous solution, whereby α-, and randomly methylated β-cyclodextrin were used as adequate phase transfer catalysts and the cyclodextrin–guest complexes were characterized by 1H NMR and 2D NMR ROESY spectroscopy. Finally, the curing properties of the diepoxide with lysine-based α-amino-ε-caprolactam were analyzed by rheological measurements.

  13. One-pot and one-step novel N-methylation of 2,6-diaminopyridine

    Directory of Open Access Journals (Sweden)

    Mehdi Nabati

    2014-07-01

    Full Text Available 2,6-Diaminopyridine is extensively used as a pharmaceutical intermediate and a hair dye coupler. It is soluble in protic solvents. Primary and secondary amines are N-methylated by various me-thods such as direct alkylation of amines with Hofmann mechanism, but in many of these me-thods due to over-alkylations, we earn a mixture of amino products. Consequently, they aren't selective in the case of secondary amines preparation. Also, the synthesis of secondary amines is a problematic field in organic chemistry. In this research, 2,6-diaminopyridine N-methylated-selictivity was done from reaction with sodium azide and orthoformic ester in low time with good yields.

  14. Structure and spectroscopic properties of N,S-coordinating 2-methyl-sulfanyl-N-[(1H-pyrrol-2-yl)methyl-idene]aniline methanol monosolvate.

    Science.gov (United States)

    Richards, D Douglas; Ang, M Trisha C; McDonald, Robert; Bierenstiel, Matthias

    2015-10-01

    The reaction of pyrrole-2-carboxaldehyde and 2-(methyl-sulfan-yl)aniline in refluxing methanol gave an olive-green residue in which yellow crystals of the title compound, C12H12N2S·CH3OH, were grown from slow evaporation of methanol at 263 K. In the crystal, hydrogen-bonding inter-actions link the aniline mol-ecule and a nearby methanol solvent mol-ecule. These units are linked by a pair of weak C-H⋯Omethanol interactions, forming inversion dimers consisting of two main molecules and two solvent molecules.

  15. Novel metal(II) coordination polymers based on N,N'-bis-(4-pyridyl)phthalamide as supercapacitor electrode materials in an aqueous electrolyte.

    Science.gov (United States)

    Gong, Yun; Li, Jian; Jiang, Peng-Gang; Li, Qing-Fang; Lin, Jian-Hua

    2013-02-07

    Based on the redox-active L (N,N'-bis-(4-pyridyl)phthalamide) ligand, two porous MOFs formulated as Zn(6)(BPC)(6)(L)(3)·9DMF (H(2)BPC = 4,4'-biphenyldicarboxylic acid) (1) and Cd(2)(TDC)(2)(L)(2)·4H(2)O (H(2)TDC = 2,5-thiophenedicarboxylic acid) (2) were synthesized and structurally characterized by single-crystal X-ray diffractions. Complex 1 features a uninodal 5-connected 3-fold interpenetrated 3D framework with {4(6).6(4)}-bnn hexagonal BN topology. Complex 2 displays a uninodal 6-connected 2-fold interpenetrated 3D framework with {4(12).6(3)}-pcu topology. When complexes 1 and 2 are used as supercapacitor electrode materials, they can provide a large voltage window as high as 2.6 V in an aqueous electrolyte, and their specific capacitances are much more than the value for the bare carbon glassy electrode. It is observed that the more the current density, the less the specific capacitance for the two kinds of supercapacitor electrode materials. The two complexes show different thermal stabilities, UV absorption and photoluminescence properties.

  16. 2-(2-Pyridyl) Benzimidazole Analogs and their beta-Glucuronidase Inhibitory Activity

    International Nuclear Information System (INIS)

    Kamil, A.; Noureen, S.

    2015-01-01

    Synthesis of 2-(2-Pyridyl) benzimidazole analogs 1-11 have been carried out and evaluated for in vitro beta-glucuronidase inhibitory potential. The compounds 4 (IC/sub 50/ = 4.06 ± 0.34 meuM), 5 (IC/sub 50/ = 09.63 ± 0.81 meuM), 1 (IC/sub 50/ = 19.66 ± 0.44 meuM), 7 (IC/sub 50/ = 24.75 ± 0.25 meuM), 6 (IC/sub 50/ = 26.30 ± 1.37 meuM), and 3 (IC/sub 50/ = 32.11 ± 0.89 meuM), showed beta-glucuronidase inhibitory activity superior to the standard D-saccharic acid 1,4-lactone, with (IC/sub 50/ = 48.4 ± 1.25 meuM). Based on structure-activity relationship, we discover a new class of potent beta-glucuronidase inhibitors. (author)

  17. [6-chloro-3-pyridylmethyl-{sup 3}H]neonicotinoids as high-affinity radioligands for the nicotinic acetylcholine receptor: preparation using NaB{sup 3}H{sub 4} and LiB{sup 3}H{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Latli, Bachir; Casida, J.E. [California Univ., Berkeley, CA (United States). Dept. of Environmental Science Policy and Management; Chit Than; Morimoto, Hiromi; Williams, P.G. [Lawrence Berkeley National Lab., CA (United States)

    1996-11-01

    NaB{sup 3}H{sub 4} and LiB{sup 3}H{sub 4} at 78% and 97% isotopic enrichments, respectively, were used in the synthesis of {sup 3}H-labeled 1-(6-chloro-3-pyridyl)-methyl-2-nitromethyleneimidazolidine (CH-IMI) and N`-[(6-chloro-3-pyridyl)methyl]-n``-cyano-n`-methylacetamidine (acetamiprid) (two very potent insecticides) and of 1-(6-chloro-3-pyridyl)methyl-2-iminoimidazolidine (desnitro-IMI) (a metabolite of the commercial insecticides imidacloprid). 6-Chloronicotinoyl chloride was treated with either NaB{sup 3}H{sub 4} in methanol or LiB{sup 3}H{sub 4} in tetrahydrofuran and the resulting alcohol transformed to 2-chloro-5-chloromethylpyridine, which was then coupled to N-cyano-N`-methylacetamidine to give [{sup 3}H] acetamiprid (45 Ci/mmol). 2-Chloro-5-chloro[{sup 3}H]methylpyridine was also reacted with ethylenediamine and the product was either refluxed in absolute ethanol with 1,1-bis(methylthio)-2-nitro-ethylene to provide [{sup 3}H]CH-IMI or reacted in toluene with a solution of cyanogen bromide to produce [{sup 3}H] desnitro-IMI (each 55 Ci/mmol). (author).

  18. Diaquabis[5-(2-pyridyltetrazolato-κ2N1,N5]iron(II

    Directory of Open Access Journals (Sweden)

    Min Hu

    2009-04-01

    Full Text Available The title complex, [Fe(C6H4N52(H2O2], was synthesized by the reaction of ferrous sulfate with 5-(2-pyridyl-2H-tetrazole (HL. The FeII atom, located on a crystallographic center of inversion, is coordinated by four N-atom donors from two planar trans-related deprotonated L ligands and two O atoms from two axial water molecules in a distorted octahedral geometry. The FeII mononuclear units are further connected by intermolecular O—H...N and C—H...O hydrogen-bonding interactions, forming a three-dimensional framework.

  19. Compound list: N-methyl-N-nitrosourea [Open TG-GATEs

    Lifescience Database Archive (English)

    Full Text Available N-methyl-N-nitrosourea MNU 00164 ftp://ftp.biosciencedbc.jp/archive/open-tggates/LA...TEST/Human/in_vitro/N-methyl-N-nitrosourea.Human.in_vitro.Liver.zip ftp://ftp.biosciencedbc.jp/archive/open-...tggates/LATEST/Rat/in_vivo/Liver/Single/N-methyl-N-nitrosourea.Rat.in_vivo.Liver.Single.zip ...

  20. The piroxicam complex of copper(II), trans-[Cu(Pir)2(THF)2], and its interaction with DNA

    Science.gov (United States)

    Hadadzadeh, Hassan; Salimi, Mona; Weil, Matthias; Jannesari, Zahra; Darabi, Farivash; Abdi, Khatereh; Khalaji, Aliakbar Dehno; Sardari, Soroush; Ahangari, Reza

    2012-08-01

    The mononuclear Cu(II) complex, trans-[Cu(Pir)2(THF)2], where Pir is 4-hydroxy-2-methyl-N-2-pyridyl-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide (piroxicam), has been prepared and characterized by elemental analysis, spectroscopic methods (UV-Vis, IR, and 1H NMR) and single crystal X-ray structure analysis. The molecular structure of the centrosymmetric complex is made up of two monoanionic bidentate Pir ligands coordinated to the Cu(II) atom through the pyridyl N atom and the carbonyl O atom of the amide group in equatorial positions. The elongated rhombic octahedral (ERO) coordination of the CuNONOO2″ chromophore is completed by the O atoms of two THF molecules in axial positions. A strong intramolecular hydrogen bond between the amide N-H function and the enolate O atom confirms the ZZZ conformation of piroxicam. In addition, CD spectroscopy and gel electrophoresis assays have been used to investigate the interaction of the complex with DNA. The results revealed that the binding of the complex with DNA led to DNA backbone distortion.

  1. Rotationally inelastic scattering of methyl radicals with Ar and N{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Tkáč, Ondřej; Orr-Ewing, Andrew J., E-mail: a.orr-ewing@bristol.ac.uk [School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS (United Kingdom); Ma, Qianli; Dagdigian, Paul J., E-mail: pjdagdigian@jhu.edu [Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218-2685 (United States); Stei, Martin [Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck (Austria)

    2015-01-07

    The rotationally inelastic scattering of methyl radical with Ar and N{sub 2} is examined at collision energies of 330 ± 25 cm{sup −1} and 425 ± 50 cm{sup −1}, respectively. Differential cross sections (DCSs) were measured for different final n′ rotational levels (up to n′ = 5) of the methyl radicals, averaged over k′ sub-levels, using a crossed molecular beam machine with velocity map imaging. For Ar as a collision partner, we present a newly constructed ab initio potential energy surface and quantum mechanical scattering calculations of state-resolved DCSs. These computed DCSs agree well with the measurements. The DCSs for both Ar and N{sub 2} collision partners are strongly forward peaked for all spectroscopic lines measured. For scattering angles below 60°, the theoretical CD{sub 3}–Ar DCSs show diffraction oscillations that become less pronounced as n′ increases, but these oscillations are not resolved experimentally. Comparisons are drawn with our recently reported DCSs for scattering of methyl radicals with He atoms.

  2. Rare earth metal bis(silylamide) complexes bearing pyridyl-functionalized indenyl ligand: synthesis, structure and performance in the living polymerization of L-lactide and rac-lactide.

    Science.gov (United States)

    Wang, Yibin; Lei, Yinlin; Chi, Shuhui; Luo, Yunjie

    2013-02-07

    Amine elimination of rare earth tris(silylamide) complexes Ln[N(SiHMe(2))(2)](3)(THF)(2) (Ln = La, Sm, Er, Lu) with 1 equiv. of the pyridyl-functionalized indenyl ligand C(9)H(7)CMe(2)CH(2)C(5)H(4)N-α afforded a series of neutral mono-indenyl-ligated rare earth metal bis(silylamide) complexes (C(9)H(6)CMe(2)CH(2)C(5)H(4)N-α)Ln[N(SiHMe(2))(2)](2) (Ln = La (1), Sm (2), Er (3), Lu (4)) in 83-87% isolated yields. Reaction of La[N(SiHMe(2))(2)](3)(THF)(2) with 2 equivalents of C(9)H(7)CMe(2)CH(2)C(5)H(4)N-α provided the neutral bis(indenyl) lanthanum mono(silylamide) complex (C(9)H(6)CMe(2)CH(2)C(5)H(4)N-α)(2)LaN(SiHMe(2))(2) (5). These complexes were characterized by elemental analysis, FT-IR and NMR (except for 3 for the strong paramagnetic property of the central metal). X-ray single crystal structural diffraction showed that 1-4 are isostructural and the central metals are four-coordinated by one indenyl ring, one nitrogen atom from the pendant pyridyl group, and two amide groups to form a distorted tetrahedral geometry; while the central metal in 5 is five-coordinated by two indenyl rings, two nitrogen atoms from the pendant pyridyl groups, and one amide group to adopt a distorted pyramidal geometry, if the indenyl ring is regarded as occupying an independent vertex. The monoanionic pyridyl-functionalized indenyl ligand is bonded to the central metal in η(5)/κ(1) constrained geometry configuration (CGC) mode. 1-4 are highly active for the ring-opening polymerization of L-lactide and rac-lactide. In the presence of 2 equivalents of benzyl alcohol, 1 shows high activity toward L-lactide and rac-lactide in a living fashion.

  3. Diiodido[methyl 2-(quinolin-8-yloxyacetate-κN]mercury(II

    Directory of Open Access Journals (Sweden)

    Yu-Hong Wang

    2012-08-01

    Full Text Available In the title mononuclear complex, [HgI2(C12H11NO3], the HgII ion has a distorted trigonal–planar coordination sphere defined by two I− anions and the N atom of a methyl 2-(quinolin-8-yloxyacetate ligand. In the crystal, face-to-face π–π stacking interactions, with a centroid–centroid distance of 3.563 (9 Å, are observed.

  4. Synthesis of high specific activity tritium labelled 1S,2S-(-)-trans-2-isothiocyanato-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)benzene acetamide, a specific irreversible ligand for kappa opioid receptors

    Energy Technology Data Exchange (ETDEWEB)

    Costa, B.R. de; Thurkauf, A.; Rothman, R.R. (National Inst. of Mental Health, Bethesda, MD (USA)); Jacobson, A.E.; Rice, K.C. (National Inst. of Digestive Diabetes, and Kidney Diseases, Bethesda, MD (USA))

    1990-11-01

    Optically pure tritium labeled 1S,2S-(-)-trans-2-isothiocyanato-N-methyl-N-(2-(1-pyrrolidinyl)cyclohexyl )benzeneacetamide, an affinity ligand specific for the kappa opioid receptor was synthesized from optically pure 1S,2S-(-)-trans-2-amino-N-methyl-N-(2-(1-pyrrolidinyl)cyclohexyl)benzeneacetamide via the sequence of dibromination (57%) followed by catalytic tritiation of the dibromide. The resulting tritium labelled aniline (14% yield, specific activity 31.2 Ci/mmol) was transformed to the title compound in 13.3% yield and 99+% radiochemical purity by treatment with thiophosgene. (author).

  5. Pentamethylcyclopentadienyl-rhodium and iridium complexes containing (N^N and N^O) bound chloroquine analogue ligands: synthesis, characterization and antimalarial properties.

    Science.gov (United States)

    Ekengard, Erik; Kumar, Kamlesh; Fogeron, Thibault; de Kock, Carmen; Smith, Peter J; Haukka, Matti; Monari, Magda; Nordlander, Ebbe

    2016-03-07

    The synthesis and characterization of twenty new pentamethylcyclopentadienyl-rhodium and iridium complexes containing N^N and N^O-chelating chloroquine analogue ligands are described. The in vitro antimalarial activity of the new ligands as well as the complexes was evaluated against the chloroquine sensitive (CQS) NF54 and the chloroquine resistant (CQR) Dd2 strains of Plasmodium falciparum. The antimalarial activity was found to be good to moderate; although all complexes are less active than artesunate, some of the ligands and complexes showed better activity than chloroquine (CQ). In particular, rhodium complexes were found to be considerably more active than iridium complexes against the CQS NF54 strain. Salicylaldimine Schiff base ligands having electron-withdrawing groups (F, Cl, Br, I and NO2) in para position of the salicyl moiety and their rhodium complexes showed good antiplasmodial activity against both the CQS-NF54 and the CQR-Dd2 strains. The crystal structures of (η(5)-pentamethylcyclopentadienyl){N(1)-(7-chloroquinolin-4-yl)-N(2)-(pyridin-2-ylmethyl)ethane-1,2-diamine)} chlororhodium(III) chloride and (η(5)-pentamethylcyclopentadienyl){(4-chloro-2-(((2-((7-chloroquinolin-4-yl)amino)ethyl)imino)methyl)phenolate)}chlororhodium(III) chloride are reported. The crystallization of the amino-pyridyl complex (η(5)-pentamethylcyclopentadienyl){(N(1)-(7-chloroquinolin-4-yl)-N(2)-(pyridin-2-ylmethyl)ethane-1,2-diamine)}chloroiridium(III) chloride in acetone resulted in the formation of the imino-pyridyl derivative (η(5)-pentamethylcyclopentadienyl){(N1-(7-chloroquinolin-4-yl)-N2-(pyridin-2-ylmethylene)ethane-1,2-diamine)}chloroiridium(III) chloride, the crystal structure of which is also reported.

  6. STUDIES ON ORGANIC PEROXIDE / N ,N-DI (2-α-METHYL-ACRYLOYLOXY PROPYL) -PARA-TOLUIDINE BINARY SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    QIU Kunyuan; FU Jie; GUO Xinqiu; FENG Xinde

    1990-01-01

    The polymerization of methyl methacrylate ( MMA )initiated by organic peroxide and polymerizable aromatic tertiary amine such as N,N-di (2-α-methylacryloyloxy propyl )-p- toluidine (MP)2PT binary system has been studied . It was found that the ( MP )2PT promotes MMA polymerization, and the kinetics of MMA polymerization fits the radical polymerization rate equation . Based on the ESR studies and the end-group analysis the initiation mechanism is proposed.

  7. 3-Methyl-4-(3-methylphenyl-5-(2-pyridyl-4H-1,2,4-triazole

    Directory of Open Access Journals (Sweden)

    Dun-Ru Zhu

    2009-05-01

    Full Text Available In the molecule of the title compound, C15H14N4, the triazole ring is oriented at dihedral angles of 30.8 (2 and 67.4 (2° with respect to the pyridine and benzene rings, respectively. The crystal structure is stabilized by C—H...N hydrogen-bonding interactions, forming chains of molecules along [overline{1}01].

  8. INTERLABORATORY STUDY OF A THERMOSPRAY-LIQUID CHROMATOGRAPHIC/MASS SPECTROMETRIC METHOD FOR SELECTED N-METHYL CARBAMATES, N-METHYL CARBAMOYLOXIMES, AND SUBSTITUTED UREA PESTICIDES

    Science.gov (United States)

    A thermospray-liquid chromatographic/mass spectrometric (TS-LC/MS) method was evaluated in an interlaboratory study for determining 3 N-methyl carbamates (bendiocarb, carbaryl, and carbofuran), 3-N-methyl carbamoyloximes (aldicarb, methomyl, and oxamyl), 2 substituted urea pestic...

  9. Expanded [CCTG]n repetitions are not associated with abnormal methylation at the CNBP locus in myotonic dystrophy type 2 (DM2) patients.

    Science.gov (United States)

    Santoro, Massimo; Fontana, Luana; Maiorca, Francesca; Centofanti, Federica; Massa, Roberto; Silvestri, Gabriella; Novelli, Giuseppe; Botta, Annalisa

    2018-03-01

    Myotonic Dystrophy type 2 (DM2) is a multisystemic disorder associated with an expanded [CCTG]n repeat in intron 1 of the CNBP gene. Epigenetic modifications have been reported in many repeat expansion disorders, including myotonic dystrophy type 1 (DM1), either as a mechanism to explain somatic repeat instability or transcriptional alterations in disease genes. The purpose of our work was to determine the effect of DM2 mutation on the methylation status of CpG islands localized in the 5' promoter region and in the 3' end of the [CCTG]n expansion of the CNBP gene. By bisulfite pyrosequencing, we characterized the methylation profile of two different CpG islands within these regions, either in whole blood and skeletal muscle tissues of DM2 patients (n=72 and n=7, respectively) and controls (n=50 and n=7, respectively). Moreover, we compared the relative mRNA transcript levels of CNBP gene in leukocytes and in skeletal muscle tissues from controls and DM2 patients. We found that CpG sites located in the promoter region showed hypomethylation, whereas CpG sites at 3' end of the CCTG array are hypermethylated. Statistical analyses did not demonstrate any significant differences in the methylation profile between DM2 patients and controls in both tissues analyzed. According to the methylation analysis, CNBP gene expression levels are not significantly altered in DM2 patients. These results show that [CCTG]n repeat expansion, differently from the DM1 mutation, does not influence the methylation status of the CNBP gene and suggest that other molecular mechanisms are involved in the pathogenesis of DM2. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Thiocyanate cadmium(II) complexes of 2,4,6-tri(2-pyridyl)-1,3,5-triazine – Synthesis, structure and luminescence properties

    International Nuclear Information System (INIS)

    Nawrot, I.; Machura, B.; Kruszynski, R.

    2014-01-01

    Two new thiocyanate cadmium(II) complexes of 2,4,6-tri(2-pyridyl)-1,3,5-triazine were synthesized and characterized. The resulted complexes [Cd(SCN)(NO 3 )(tptz)(H 2 O)] (1) and [Cd(SCN) 2 (tptz)(MeOH)] (2) were studied by IR, UV–vis spectroscopy and single crystal X-ray analysis. The luminescent properties of 1 and 2 were studied in solution and solid state and compared with the free ligand. To get detailed insight into the electronic structure and spectroscopic properties of [Cd(SCN)(NO 3 )(tptz)(H 2 O)] and [Cd(SCN) 2 (tptz)(MeOH)], the density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were performed. - Highlights: • Two novel thiocyanate cadmium(II) compounds of 2,4,6-tri(2-pyridyl)-1,3,5-triazine were synthesized. • The compounds were identified by IR, UV–vis spectroscopy and X-ray analysis. • The fluorescence properties of the complexes were examined and compared with the free ligand. • The electronic spectra were investigated at the TD-DFT level employing B3LYP/LANL2DZ

  11. New Synthesis, Structure and Analgesic Properties of Methyl 1-R-4-Methyl-2,2-Dioxo-1H-2λ6,1-Benzothiazine-3-Carboxylates

    Directory of Open Access Journals (Sweden)

    Liliana Azotla-Cruz

    2017-01-01

    Full Text Available According to the principles of the methodology of bioisosteric replacements a series of methyl 1-R-4-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylates has been obtained as potential analgesics. In addition, a fundamentally new strategy for the synthesis of compounds of this chemical class involving the introduction of N-alkyl substituent at the final stage in 2,1-benzothiazine nucleus already formed has been proposed. Using nuclear magnetic resonance (NMR spectroscopy, mass spectrometry and X-ray diffraction analysis it has been proven that in the DMSO/K2CO3 system the reaction of methyl 4-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylate and alkyl halides leads to formation of N-substituted derivatives with good yields regardless of the structure of the alkylating agent. The peculiarities of NMR (1Н and 13С spectra of the compounds synthesized, their mass spectrometric behavior and the spatial structure are discussed. In N-benzyl derivative the ability to form a monosolvate with methanol has been found. According to the results of the pharmacological testing conducted on the model of the thermal tail-flick it has been determined that replacement of 4-ОН-group in methyl 1-R-4-hydroxy-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylates for the methyl group is actually bioisosteric since all methyl 1-R-4-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylates synthesized demonstrated a statistically significant analgesic effect. The majority of the substances can inhibit the thermal pain response much more effective than piroxicam in the same dose. Under the same conditions as an analgesic the N-methyl-substituted analog exceeds not only piroxicam, but more active meloxicam as well. Therefore, it deserves in-depth biological studies on other experimental models.

  12. Selectively catalytic activity of metal–organic frameworks depending on the N-position within the pyridine ring of their building blocks

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Haitao, E-mail: xuhaitao@ecust.edu.cn [School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237 (China); Gou, Yongxia; Ye, Jing; Xu, Zhen-liang [School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237 (China); Wang, Zixuan [School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237 (China)

    2016-05-15

    Iron metal–organic frameworks (MOFs) [Fe(L){sub 2}(SCN){sub 2}]{sub ∝} (L1: 4-bpdh=2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene for 1Fe; and L2: 3-bpdh=2,5-bis(3-pyridyl)-3,4-diaza-2,4-hexadiene for 2Fe) were assembled in a MeOH–H{sub 2}O solvent system. 1Fe exhibits a two-dimensional extended-grid network, whereas 2Fe exhibits a stair-like double-chain; the N-position within the pyridine ring of the complexes was observed to regulate the MOF structure as layers or chains. Furthermore, selectively catalytic activity was observed for the layered MOF but not the chain-structured MOF; micro/nanoparticles of the layered MOF were therefore investigated for new potential applications of micro/nano MOFs. - Graphical abstract: Iron metal–organic frameworks (MOFs) [Fe(L){sub 2}(SCN){sub 2}]{sub ∝} (L1: 4-bpdh=2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene for 1Fe; and L2: 3-bpdh=2,5-bis(3-pyridyl)-3,4-diaza-2,4-hexadiene for 2Fe) were assembled in a MeOH–H{sub 2}O solvent system. The N-position within the pyridine ring of the complexes was observed to regulate the MOF structure as layers or chains. Selectively catalytic activity was observed for the layered MOF but not the chain-structured MOF. - Highlights: • Synthesis and structure of metal–organic framework [Fe(L){sub 2}(SCN){sub 2}]{sub ∝}. • Selectively catalytic activity depending on the N-position within the pyridine ring. • The degradation and conversion of methyl orange.

  13. Selectively catalytic activity of metal–organic frameworks depending on the N-position within the pyridine ring of their building blocks

    International Nuclear Information System (INIS)

    Xu, Haitao; Gou, Yongxia; Ye, Jing; Xu, Zhen-liang; Wang, Zixuan

    2016-01-01

    Iron metal–organic frameworks (MOFs) [Fe(L) 2 (SCN) 2 ] ∝ (L1: 4-bpdh=2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene for 1Fe; and L2: 3-bpdh=2,5-bis(3-pyridyl)-3,4-diaza-2,4-hexadiene for 2Fe) were assembled in a MeOH–H 2 O solvent system. 1Fe exhibits a two-dimensional extended-grid network, whereas 2Fe exhibits a stair-like double-chain; the N-position within the pyridine ring of the complexes was observed to regulate the MOF structure as layers or chains. Furthermore, selectively catalytic activity was observed for the layered MOF but not the chain-structured MOF; micro/nanoparticles of the layered MOF were therefore investigated for new potential applications of micro/nano MOFs. - Graphical abstract: Iron metal–organic frameworks (MOFs) [Fe(L) 2 (SCN) 2 ] ∝ (L1: 4-bpdh=2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene for 1Fe; and L2: 3-bpdh=2,5-bis(3-pyridyl)-3,4-diaza-2,4-hexadiene for 2Fe) were assembled in a MeOH–H 2 O solvent system. The N-position within the pyridine ring of the complexes was observed to regulate the MOF structure as layers or chains. Selectively catalytic activity was observed for the layered MOF but not the chain-structured MOF. - Highlights: • Synthesis and structure of metal–organic framework [Fe(L) 2 (SCN) 2 ] ∝ . • Selectively catalytic activity depending on the N-position within the pyridine ring. • The degradation and conversion of methyl orange.

  14. Synthesis of (2-pyridyl)-Acetyl Chitosan and Its Antioxidant Activity

    International Nuclear Information System (INIS)

    Li, Rongchun

    2011-01-01

    In this paper, chloracetyl chitosan (CACTS) was prepared at first. In the molecules of CACTS, there are active chlorine groups, which can take part in other reactions. Thus, number of chitosan derivatives will be obtained after chlorine is substituted. Choosing pyridine as the active group, a novel water-soluble chitosan derivative, (2-pyridyl)-acetyl chitosan (PACTS) was obtained and its antioxidant activity against hydroxyl radicals and superoxide radicals was assessed. The results indicated that PACTS had better antioxidant activity than that of chitosan, carboxymethyl chitosan (CMCTS), hydroxypropyl chitosan (HPCTS), and Vitamin C. And the IC 50 values against hydroxyl radicals and superoxide radicals were 0.31 mg/mL and 0.21 mg/mL, respectively

  15. SPE-GC/FTD determination of N-methyl-2-pyrrolidone and its metabolites in urine.

    Science.gov (United States)

    Kubota, Ryuichi; Endo, Yoko; Takeuchi, Akito; Inoue, Yoshinori; Ogata, Hiroko; Ogawa, Masanori; Nakagawa, Tomoo; Onda, Nobuhiko; Endo, Ginji

    2007-07-01

    An analytical method using a combination of solid-phase extraction (SPE) and gas chromatography with a flame thermionic detector (GC/FTD) was developed for determination of N-methyl-2-pyrrolidone (NMP), N-methylsuccinimide (MSI), and 2-hydroxy-N-methylsuccinimide (2-HMSI) in human urine. The SPE cartridge of poly(divinylbenzene/hydroxymethacrylate) used was directly loaded with urine sample, followed by elution with methyl isobutyl ketone (MIBK) and subsequent centrifugation, and the supernatant was injected into the capillary GC using a DB1701. This method allowed efficient separation of NMP, MSI, and 2-HMSI, which were nearly free of interference by other GC peaks arising from urine. Recoveries of NMP, MSI, and 2-HMSI from the SPE cartridge were about 98, 101, and 67%, respectively, with limits of detection of 0.04, 0.02, and 0.06 mg/L, respectively, which met the regulatory requirements. The present method was used for assay in biological monitoring of workers exposed to NMP in their occupational environment.

  16. Structure and thermal property of N,N-diethyl-N-methyl-N-2-methoxyethyl ammonium tetrafluoroborate-H2O mixtures

    International Nuclear Information System (INIS)

    Imai, Yusuke; Abe, Hiroshi; Goto, Takefumi; Yoshimura, Yukihiro; Michishita, Yosuke; Matsumoto, Hitoshi

    2008-01-01

    By in situ observations using simultaneous X-ray diffraction and differential scanning calorimetry method, complicated phase transitions were observed in N,N-diethyl-N-methyl-N-2-methoxyethyl ammonium tetrafluoroborate, [DEME][BF 4 ] and H 2 O mixtures. In pure [DEME][BF 4 ], two different crystal structures were determined below crystallization temperature, T c . Two kinds of crystals correspond to two stages of melting upon heating. T c decreases with increasing in the H 2 O content of [DEME][BF 4 ]-H 2 O mixture. Around 6.7 mol% H 2 O, an amorphous solid, however, was formed without crystallization on cooling. Glass transition temperature, T g , of the amorphous phase depends on cooling rate of the mixture. On heating, the amorphous solid transformed to a crystal accompanied by an exothermal peak. This unusual cold crystallization is induced by H 2 O molecules. Two different dynamic components were observed in a Raman spectrum of the amorphous phase, where the lower Raman band is crystal-like and the higher one is liquid-like. At higher H 2 O concentration, coexistence of the amorphous solid and crystal was realized below T c , and the cold crystallization also occurred. In spite of a variety of phase transitions, the crystal structure of [DEME][BF 4 ]-H 2 O mixtures is the same one as pure [DEME][BF 4

  17. Theoretical study on electronic structures and optical properties of blue phosphorescent Iridium(III) complexes with C{sup ∧}N and N{sup ∧}N ligands

    Energy Technology Data Exchange (ETDEWEB)

    Shang, Xiaohong [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); College of Chemistry and Life Science, Changchun University of Technology, Changchun 130024 (China); Liu, Yuqi; Qu, Xiaochun [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Wu, Zhijian, E-mail: zjwu@ciac.jl.cn [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2013-11-15

    We report a quantum-chemical study on the electronic structures and optical properties of two series of heteroleptic iridium(III) complexes [(dfb-pz){sub 2}Ir(N{sup ∧}N+sub)], [dfb-pz=2,4-difluorobenzyl-N-pyrazole, sub indicates substituent group, N{sup ∧}N+sub=tphppz=4-tert-butyl-2-(5-phenyl-[1,2,4]triazol-3-yl)-pyridine (1a), tmppz=4-tert-butyl-2-(5-methyl-[1,2,4]triazol-3-yl)-pyridine (1b), fphppz=4-fluoro-phenyl-5-(2-pyridyl)pyrazole (1c), and fmphppz=4-trifluoromehtyl-phenyl-5-(2-pyridyl)pyrazole (1d)]; with [(C{sup ∧}N+sub){sub 2}Ir(fppz)], [C{sup ∧}N=b-pz=benzyl-N-pyrazole, fppz=3-trifluoromethyl-5-(2-pyridyl)pyrazole, C{sup ∧}N+sub=dfb-pz=2,4-difluorobenzyl-N-pyrazole (2a), tfmfb-pz=2-trifluoromethyl-5-fluorobenzyl-N-pyrazole (2b), phb-pz=3-phenyl-benzyl-N-pyrazole (2c), and dfphb-pz=3-phenyl-2,4-difluorobenzyl-N-pyrazole (2d)]. The calculated results shed light on the reasons of the remarkably manipulated excited-state and electroluminescent properties through substitution effect. The phenyl ring on main ligands can enhance the π-conjugation of the main ligands moiety and increase the metal-ligand bond strength for 2c and 2d, then enhancing the transition strength. From 1c, 1d, 2c, and 2d, it can also be seen that substituents on the terminal phenyl ring have a slight effect on the excited energy because the distance between the substituents and the ancillary (or main) ligand is interrupted by the phenyl moiety. The calculated absorption and luminescence properties of the four complexes 1a, 1b, 2a, and 2b are compared with the available experimental data and a good agreement is obtained. Furthermore, the assumed complex 1c, 2c, and 2d possess better charge transfer abilities and more balanced charge transfer rates. The designed complexes 2c and 2d are potential candidates for blue phosphorescent materials. -- Highlights: • Two series of electroluminescent iridium(III) complexes have been studied. • The charge transfer properties are affected

  18. Synthesis and Molecular Structures of Two [1,4-bis(3-pyridyl-2,3-diazo-1,3-butadiene]-dichloro-Zn(II Coordination Polymers

    Directory of Open Access Journals (Sweden)

    Hsin-Ta Wang

    2006-08-01

    Full Text Available Two novel coordination polymers with 3D metal-organic frameworks (MOFs have been synthesized by reacting 1,4-bis(3-pyridyl-2,3-diazo-1,3-butadiene (L with zinc dichloride. Both compounds have the same repeating unit consisting of a distorted tetrahedral Zn(II center coordinated by two chlorides and two pyridyl nitrogen atoms of two bridging bismonodentate L ligands, however, different structural conformations have been found, one forming a helical chain and the other producing a square-wave chain. The intermolecular C−H···Cl hydrogen bonds in 1 and 2 play important roles in the formation of three-dimensional coordination polymers. Compound 1 crystallized in an orthorhombic space group Pna21 with a = 7.9652(3, b = 21.4716(7, c = 8.2491(3Å, V = 1410.81(9 Å 3 and Z = 4. Compound 2 crystallized in a monoclinic space group P21/n with a = 9.1752(3, b = 14.5976(4, c = 10.3666(3 Å , β = 98.231(2°, V = 1374.16(7 Å 3 and Z = 4.

  19. Hexaaquabis[3,5-bis(hydroxyimino-1-methyl-2,4,6-trioxocyclohexanido-κ2N3,O4]barium tetrahydrate

    Directory of Open Access Journals (Sweden)

    Nguyen Dinh Do

    2013-11-01

    Full Text Available In the title compound, [Ba(C7H5N2O52(H2O6]·4H2O, the Ba2+ cation lies on a twofold rotation axis and is ten-coordinated by two 3,5-bis(hydroxyimino-1-methyl-2,4,6-trioxocyclohexanide oxo O atoms [Ba—O = 2.8715 (17 Å], two hydroxyimino N atoms [Ba—N = 3.036 (2 Å], and six water molecules [Ba—O = 2.847 (2, 2.848 (2, and 2.880 (2 Å]. The 3,5-bis(hydroxyimino-1-methyl-2,4,6-trioxocyclohexanide monoanions act in a bidentate chelating manner, coordinating through an N atom of the non-deprotonated hydroxyimino group and an O atom of the neighboring oxo group. Two lattice water molecules are located in the cavities of the framework and are involved in hydrogen bonding to O atoms of one of the coordinating water molecules and the O atom of a keto group of the ligand. As a result, a three-dimensional network is formed.

  20. Solid state photodimerization in an organic salt of 1,2-bis(4-pyridyl ...

    Indian Academy of Sciences (India)

    Abdul Malik P Peedikakkal

    compound 1 undergoes photodimerization reaction in solid state to produce stereo-specific rctt-tetrakis(4- pyridyl)cyclobutane .... of isomers was calculated based on the integrated intensity of 1H NMR signals .... A combinatorial math- ematical ...

  1. Fabrication of a PVC membrane samarium(III) sensor based on N,N′,N″-tris(4-pyridyl)trimesic amide as a selectophore

    International Nuclear Information System (INIS)

    Zamani, Hassan Ali; Naghavi-Reyabbi, Fatemeh; Faridbod, Farnoush; Mohammadhosseini, Majid; Ganjali, Mohammad Reza; Tadjarodi, Azadeh; Rad, Maryam

    2013-01-01

    A new ion-selective electrode for Sm 3+ ion is described based on the incorporation of N,N′,N″-tris(4-pyridyl)trimesic amide (TPTA) in a poly(vinylchloride) (PVC) matrix. The membrane sensor comprises nitrobenzene (NB) as a plasticizer, and oleic acid (OA) as an anionic additive. The sensor with the optimized composition shows a Nernstian potential response of 19.8 ± 0.5 mV decade −1 over a wide concentration range of 1.0 × 10 −2 and 1 × 10 −6 mol L −1 , with a lower detection limit of 4.7 × 10 −7 mol L −1 and satisfactor applicable pH range of 3.6–9.2. Having a short response time of less than 10 s and a very good selectivity towards the Sm 3+ over a wide variety of interfering cations (e.g. alkali, alkaline earth, transition and heavy metal ions) the sensor seemed to be a promising analytical tool for determination of the Sm 3+ . Hence, it was used as an indicator electrode in the potentiometric titration of samarium ion with EDTA. It was also applied to the direct samarium recovery in binary mixtures. - Highlights: ► A new Sm 3+ -PVC membrane sensor is introduced for determination of Sm 3+ ions in the solutions. ► N,N′,N″-tris(4-pyridyl)trimesic amide was used as a suitable selectophore for samarium sensor. ► Detection limit of the sensor is 4.7 × 10 −7 mol L −1 with a short response time of less than 10 s.

  2. Amide-based inhibitors of p38alpha MAP kinase. Part 2: design, synthesis and SAR of potent N-pyrimidyl amides.

    Science.gov (United States)

    Tester, Richland; Tan, Xuefei; Luedtke, Gregory R; Nashashibi, Imad; Schinzel, Kurt; Liang, Weiling; Jung, Joon; Dugar, Sundeep; Liclican, Albert; Tabora, Jocelyn; Levy, Daniel E; Do, Steven

    2010-04-15

    Optimization of a tri-substituted N-pyridyl amide led to the discovery of a new class of potent N-pyrimidyl amide based p38alpha MAP kinase inhibitors. Initial SAR studies led to the identification of 5-dihydrofuran as an optimal hydrophobic group. Additional side chain modifications resulted in the introduction of hydrogen bond interactions. Through extensive SAR studies, analogs bearing free amino groups and alternatives to the parent (S)-alpha-methyl benzyl moiety were identified. These compounds exhibited improved cellular activities and maintained balance between p38alpha and CYP3A4 inhibition. Copyright 2010 Elsevier Ltd. All rights reserved.

  3. EPR study of gamma-irradiated N-methyl-L-alanine, DL-2-methyl glutamic acid hemihydrate and Di-leucine hydrochloride in solid state

    Science.gov (United States)

    Sütçü, Kerem; Osmanoğlu, Y. Emre

    2017-12-01

    In this study, it was aimed to investigate ɣ-irradiated powders of N-methyl-L-alanine (NMLA), DL-2-methyl glutamic acid hemihydrate (DL2MGAH), and Di-leucine hydrochloride (DLHCl) at room temperature by electron paramagnetic resonance spectroscopy. After the γ-irradiation the samples indicated the existence of the CH3ĊNHCH3COOH, HOOCCH3NH2CĊHCH2COOH·1/2H2O and (CH3)2ĊCH2CH NHCOOHCOCH (NH2HCl) CH2CH (CH3)2 radicals, respectively. The spectral parameters of the radicals were determined. The results were compared with the earlier studies and discussed accordingly.

  4. Synthesis and Molecular Structures of Two [1,4-bis(3-pyridyl)-2,3-diazo-1,3-butadiene]-dichloro-Zn(II) Coordination Polymers

    OpenAIRE

    Lee, Gene-Hsiang; Wang, Hsin-Ta

    2006-01-01

    Two novel coordination polymers with 3D metal-organic frameworks (MOFs) have been synthesized by reacting 1,4-bis(3-pyridyl)-2,3-diazo-1,3-butadiene (L) with zinc dichloride. Both compounds have the same repeating unit consisting of a distorted tetrahedral Zn(II) center coordinated by two chlorides and two pyridyl nitrogen atoms of two bridging bismonodentate L ligands, however, different structural conformations have been found, one forming a helical chain and the other producing a square-wa...

  5. (E-2-Methyl-6-{[(5-methylpyridin-2-ylimino]methyl}phenol

    Directory of Open Access Journals (Sweden)

    Md. Azharul Arafath

    2017-01-01

    Full Text Available In the title compound, C14H14N2O, the dihedral angle between the aromatic rings is 5.54 (9°. The conformation is reinforced by an intramolecular O—H...N hydrogen bond, which closes an S(6 ring. The pyridine N atom and methyl group lie to opposite sides of the molecule. In the crystal, the molecules are linked into a zigzag chain propagating in [0-11] by weak C—H...O hydrogen bonds.

  6. Synthesis of N-methyl and N-11C-methyl spiperone by phase transfer catalysis in anhydrous solvent

    International Nuclear Information System (INIS)

    Omokawa, Hiroyoshi; Tanaka, Akira; Iio, Mayumi; Nishihara, Yoshiaki; Inoue, Osamu; Yamazaki, Toshio.

    1985-01-01

    Spiperone, a butyrophenone neuroleptic drug, has been used in binding studies of dopamine receptors. Langstrom et al. developed N- 11 C-methyl spiperone, and, in cooperate with Wagner et al., made it possible to visualize the distribution of dopamine receptors in the human brain in vivo. In this paper, we independently developed another synthetic method of N- 11 C-methyl spiperone using the phase transfer catalyst in an anhydrous solvent. Separation of the product is feasible only by passing the reactant solution through a Millipore filter and injecting it onto high pressure liquid chromatography (HPLC). The time required for the synthesis and purification of N- 11 C-methyl spiperone from 11 C-methyl iodide and spiperone was 20 min. Radiochemical yield exceeded 35 % against 11 C-methyl iodide without correcting decay of the radioactivity. (author)

  7. 4-Methyl-N-(2-methylbenzoylbenzenesulfonamide

    Directory of Open Access Journals (Sweden)

    B. Thimme Gowda

    2010-06-01

    Full Text Available In the title compound, C15H15NO3S, the conformation of the N—H bond in the C—SO2—NH—C(O segment is anti to the C=O bond. Further, the conformation of the C=O bond is syn to the ortho-methyl group in the benzoyl ring. The dihedral angle between the sulfonyl benzene ring and the —SO2—NH—C—O segment is 87.1 (1° and that between the sulfonyl and the benzoyl benzene rings is 58.2 (1°. In the crystal structure, molecules are linked by pairs of N—H...O(S hydrogen bonds, forming inversion dimers.

  8. Mercury coordination polymers with flexible ethane-1,2-diyl-bis-(pyridyl-3-carboxylate): Synthesis, structures, thermal and luminescent properties

    Energy Technology Data Exchange (ETDEWEB)

    Vallejos, Javier [Departamento de Química, Universidad Católica del Norte, Av. Angamos 0610, Antofagasta (Chile); Brito, Iván, E-mail: ivanbritob@yahoo.com [Departamento de Quimica, Universidad de Antofagasta, Av. Angamos 601, Antofagasta (Chile); Cárdenas, Alejandro [Departamento de Física, Universidad de Antofagasta, Av. Angamos 601, Antofagasta (Chile); Llanos, Jaime [Departamento de Química, Universidad Católica del Norte, Av. Angamos 0610, Antofagasta (Chile); Bolte, Michael [Institut für Anorganische Chemie der Goethe—Universität Frankfurt, Max-von-Laue-Strasse 7, D-60438 Frankfurt am Main (Germany); López-Rodríguez, Matías [Instituto de Bio-Orgánica “Antonio González”, Universidad de La Laguna, Astrofísico Francisco Sánchez N° 2, La Laguna, Tenerife (Spain)

    2015-03-15

    The reaction of the flexible ligand, ethane-1,2-diyl-bis-(pyridyl-3-carboxylate), (L) with HgI{sub 2} and HgBr{sub 2} salts under the same experimental conditions leads to the formation of two coordination polymers with different motifs: ([Hg(L)(Br{sub 2})]){sub n}(1) and ([Hg(L)(I{sub 2})]){sub n}(2). In both compounds, the ligand, (L) acts in a μ2-N:N′-bidentate fashion to link HgBr{sub 2} and HgI{sub 2} units to form a linear and helical chain motif, along [1 0 0] for (1) and [0 0 1] for (2). The ethylene moiety of (L) has gauche and trans conformation in compounds (1) and (2), respectively. The flexible conformation of L produces differences in the optical and crystal properties of the two compounds. - Graphical abstract: This work demonstrates how the HgX{sub 2} units are coordinates by bi-dentate ligand forming polymeric coordination complexes by self-assembly of both chemical units.- Highlights: • News 1-D d{sup 10} transition metal coordination polymers. • The photoluminescent properties have been measured. • The thermal properties have been measured.

  9. Technetium(V)-nitrido complexes of dithiocarbazic acid derivatives. Reactivity of [Tc≡N]2+ core towards Schiff bases derived from S-methyl dithiocarbazate. Crystal structures of [S-methyl 3-(2-hydroxyphenyl-methylene) dithiocarbazato]intrido(triphenylphosphine)technetium(V) and bis(S-methyl 3-isopropylidenedithiocarbazato)nitridotechnetium(V)

    International Nuclear Information System (INIS)

    Marchi, A.; Duatti, A.; Rossi, R.; Magon, L.; Bertolasi, V.; Ferretti, V.; Gilli, G.; Pasqualini, R.

    1988-01-01

    As a potential alternative approach to lipophilic square-pyramidal technetium complexes, we investigate here the synthesis of new Tcsup(V) complexes, containing the [Tc''ident to''N] 2+ core, with bi- and tri-dentate Schiff bases derived from S-methyl dithiocarbazate, NH 2 NHC(=S)SCH 3 . Square-pyramidal complexes having an apical Tcsup(V) ≡ N group, with bis(quinoline-8-thiolato), [TcN(C 9 H 6 NS) 2 ], and bis(diethyldithiocarbamate), [TcN(S 2 CNEt 2 ) 2 ], have been reported. In this paper, we report the synthesis and characterization of a series of technetium(V)-nitrido complexes with the ligands illustrated, obtained by reduction of the technetium(VI) complex [TcNCl 4 ] - or by ligand substitution of the Tcsup(V) complex [TcNCl 2 (PPh 3 ) 2 ]. We discuss also the crystal structures of the complexes [TcNL 1 (PPh 3 )] [H 2 L 1 = S-methyl 3-(2-hydroxy-phenylmethylene)dithiocarbazate] and [TcN(L 12 ) 2 ] (HL 12 S-methyl 3-isopropylidenedithiocarbazate. (author)

  10. 2-Bromo-2-methyl-N-p-tolylpropanamide

    Directory of Open Access Journals (Sweden)

    Rodolfo Moreno-Fuquen

    2011-06-01

    Full Text Available In the title molecule, C11H14BrNO, there is twist between the mean plane of the amide group and the benzene ring [C(=O—N—C...;C torsion angle = −31.2 (5°]. In the crystal, intermolecular N—H...O and weak C—H...O hydrogen bonds link molecules into chains along [100]. The methyl group H atoms are disordered over two sets of sites with equal occupancy.

  11. Trichlorido[(meth­yl{2-[meth­yl(2-pyridyl­meth­yl)amino]eth­yl}amino)acetonitrile]iron(III) methanol hemisolvate

    Science.gov (United States)

    Nielsen, Anne; McKenzie, Christine J.; Bond, Andrew D.

    2009-01-01

    The title compound, [FeCl3(C12H18N4)]·0.5CH3OH, contains an FeIII ion in a distorted octa­hedral coordination environment. The neutral N,N′,N′′-tridentate ligand adopts a fac coordination mode, and chloride ligands lie trans to each of the three coordinated N atoms. In the crystal, the complexes form columns extending parallel to the approximate local threefold axes of the FeN3Cl3 octa­hedra, and the columns are arranged so that the uncoordinated nitrile groups align in an anti­parallel manner and the pyridyl rings form offset face-to-face arrangements [inter­planar separations = 2.95 (1) and 3.11 (1) Å; centroid–centroid distances = 5.31 (1) and 4.92 (1) Å]. The methanol solvent mol­ecule is disordered about a twofold rotation axis. PMID:21578169

  12. Polymer complexes.. XXXX. Supramolecular assembly on coordination models of mixed-valence-ligand poly[1-acrylamido-2-(2-pyridyl)ethane] complexes

    Science.gov (United States)

    El-Sonbati, A. Z.; El-Bindary, A. A.; Diab, M. A.

    2003-02-01

    The build-up of polymer metallic supramolecules based on homopolymer (1-acrylamido-2-(2-pyridyl)ethane (AEPH)) and ruthenium, rhodium, palladium as well as platinum complexes has been pursued with great interest. The homopolymer shows three types of coordination behaviour. In the mixed valence paramagnetic trinuclear polymer complexes [( 11)+( 12)] in the paper and in mononuclear polymer complexes ( 1)-( 5) it acts as a neutral bidentate ligand coordinating through the N-pyridine and NH-imino atoms, while in the mixed ligand diamagnetic poly-chelates, which are obtained from the reaction of AEPH with PdX 2 and KPtCl 4 in the presence of N-heterocyclic base consisting of polymer complexes ( 9)+( 10), and in monouclear compounds ( 6)-( 8), it behaves as a monobasic bidentate ligand coordinating through the same donor atoms. In mononuclear compounds ( 13)+( 14) it acts as a monobasic and neutral bidentate ligand coordinating only through the same donor atoms. Monomeric distorted octahedral or trimeric chlorine-bridged, approximately octahedral structures are proposed for these polymer complexes. The poly-chelates are of 1:1, 1:2 and 3:2 (metal-homopolymer) stoichiometry and exhibit six coordination. The values of ligand field parameters were calculated. The homopolymer and their polymer complexes have been characterized physicochemically.

  13. Methyl 4-[N-(5-bromopyrimidin-2-ylcarbamoyl]benzoate

    Directory of Open Access Journals (Sweden)

    Hui-Ling Hu

    2012-08-01

    Full Text Available In the title compound, C13H10BrN3O3, the pyrimidine and benzene rings are twisted with an interplanar angle of 58.4 (1°. The secondary amide group adopts a cis conformation with an H—N—C—O torsion angle of 14.8 (1°. In the crystal, molecules are connected into inversion dimers via pairs of N—H...N hydrogen bonds, generating an R22(8 motif. The dimers are further connected through a C—Br...O interaction [3.136 (1 Å and 169.31 (1°] into a chain along [110]. Weak C—H...N hydrogen bonds between the methyl benzoate groups and pyrimidine rings are also observed in the crystal structure.

  14. Determination of trace amounts of nickel(II) with α-(2-Benzimidazolyl)-α',α''-(N-5-nitro-2-pyridyl hydrazone) toluene in the presence of triton X-100 by fluorescence method

    International Nuclear Information System (INIS)

    Park, Chan Il; Kim, Hyun Soo; Cha, Ki Won

    2000-01-01

    A method is described for the fluorimetric determination of nicke, based on the formation of Ni(II)-α-(2-Benzimidazolyl)-α',α''-(N-5-nitro-2-pyridyl hydrazone)-toluene complex in the presence of a non-ionic surfactant. The complex has practically no fluorescence in the absence of surfactant, but the addition of Triton X-100 makes possible the fluorimetric determination of low concentrations of Ni(II) as it enhances the fluorescence intensity of the complex by up to about 5-fold. This method is very sensitive and selective for the direct determination of nickel ion. The optimum conditions are a Triton X-100 concentration of 2.0 mL (5.0%, v/v) and pH 9.0 ± 0.2 (ammonium chloride-ammonia buffer). The fluorescence is measured at 337 nm of emission wavelength under 300 nm of excitation wavelength. The fluorescence intensity is a linear function of the concentration of Ni(II) in the range 5-70 ng/mL, and the detection limit is 2.0 ng/mL. The proposed method has been successfully applied to the determination of trace amounts of Ni(II) in food and human hair samples

  15. Spectral characteristics of 2-(4'-amino-3-pyridyl)benzimidazole: Effects of solvent and acid or base concentration

    International Nuclear Information System (INIS)

    Dogra, Sneh K.

    2006-01-01

    Spectral characteristics of 2-(4'-amino-3-pyridyl)benzimidazole (4-A3PyBI) have been studied in different solvents, as well as at different acid or base concentrations using absorption, fluorescence excitation and fluorescence spectroscopy. Excited singlet state (S 1 ) lifetimes for each species were measured using nanosecond time-dependent spectrofluorimeter. AM1 semi-empirical and density functional theoretical (DFT) calculations were performed on each species for the spectral assignment. From the above results it is concluded that 4-A3PyBI exists only in the amine form. First protonation occurs at pyridine=N- atom and second protonation at the benzimidazole (BI)=N- atom. When dication (DC) species is excited, two emission bands are observed, having the same fluorescence excitation spectra, suggesting the same ground state (S ) precursor. Short wavelength (SW) emission band is assigned to the π-π* transition and long wavelength (LW) emission to the charge transfer transition. First deprotonation in S state occurs from >N-H moiety, whereas in S 1 state it is from -NH 2 group. Monoanion (MA) so formed in S 1 state is non-fluorescent. Dianion (DA) is formed by further deprotonating >N-H moiety in S 1 state and it is fluorescent. pK a values were determined and discussed

  16. Identification of AICP as a GluN2C-Selective N-Methyl-d-Aspartate Receptor Superagonist at the GluN1 Glycine Site

    DEFF Research Database (Denmark)

    Jessen, Maja; Frederiksen, Kristen; Yi, Feng

    2017-01-01

    N-methyl-d-aspartate (NMDA)-type ionotropic glutamate receptors mediate excitatory neurotransmission in the central nervous system and are critically involved in brain function. NMDA receptors are also implicated in psychiatric and neurological disorders and have received considerable attention....../2A-D), in which DCS is a superagonist at GluN2C-containing receptors compared with glycine and a partial agonist at GluN2B-containing receptors. Here, we identify (R)-2-amino-3-(4-(2-ethylphenyl)-1H-indole-2-carboxamido)propanoic acid (AICP) as a glycine site agonist with unique GluN2-dependent...

  17. Synthesis of methyl-2 O-tolyl-3 quinazolone-4 {sup 14}C-2; Synthese de la methyl-2 O-tolyl-3 quinazolone-4 {sup 14}C-2

    Energy Technology Data Exchange (ETDEWEB)

    Herbert, M; Pichat, L [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    Description of the preparation of methyl-2 O-tolyl-3 quinazolone-4 {sup 14}C-2 (abbreviated to M.T.Q.), using N-acetyl {sup 14}C-1 anthranilic acid. The overall yield reaches 72 per cent with respect to acetyl chloride {sup 14}C-1. By applying the same method to acetyl chloride {sup 14}C-2, M.T.Q. labelled on the methyl group could be obtained. (author) [French] Description de la preparation de la methyl-2 O-tolyl-3 quinazolone-4 {sup 14}C-2 (abregee en M.T.Q.) par l'intermediaire de l'acide N-acetyl {sup 14}C-1 anthranilique. Le rendement global atteint 72 pour cent par rapport au chlorure d'acetyle {sup 14}C-1. La meme methode appliquee au chlorure d'acetyle {sup 14}C-2 permettrait d'obtenir la M.T.Q. marquee sur le groupement methyle. (auteur)

  18. New coordination polymers from 1D chain, 2D layer to 3D framework constructed from 1,2-phenylenediacetic acid and 1,3-bis(4-pyridyl)propane flexible ligands

    Science.gov (United States)

    Xin, Ling-Yun; Liu, Guang-Zhen; Wang, Li-Ya

    2011-06-01

    The hydrothermal reactions of Cd, Zn, or Cu(II) acetate salts with H 2PHDA and BPP flexible ligands afford three new coordination polymers, including [Cd(PHDA)(BPP)(H 2O)] n(1), [Zn(PHDA)(BPP)] n(2), and [Cu 2(PHDA) 2(BPP)] n(3) (H 2PHDA=1,2-phenylenediacetic acid, BPP=1,3-bis(4-pyridyl)propane). The single-crystal X-ray diffractions reveal that all three complexes feature various metal carboxylate subunits extended further by the BPP ligands to form a diverse range of structures, displaying a remarked structural sensitivity to metal(II) cation. Complex 1 containing PHDA-bridged binuclear cadmium generates 1D double-stranded chain, complex 2 results in 2D→2D interpenetrated (4,4) grids, and complex 3 displays a 3D self-penetrated framework with 4 86 68 rob topology. In addition, fluorescent analyses show that both 1 and 2 exhibit intense blue-violet photoluminescence in the solid state.

  19. Propofol effectively inhibits lithium-pilocarpine- induced status epilepticus in rats via downregulation of N-methyl-D-aspartate receptor 2B subunit expression

    Science.gov (United States)

    Wang, Henglin; Wang, Zhuoqiang; Mi, Weidong; Zhao, Cong; Liu, Yanqin; Wang, Yongan; Sun, Haipeng

    2012-01-01

    Status epilepticus was induced via intraperitoneal injection of lithium-pilocarpine. The inhibitory effects of propofol on status epilepticus in rats were judged based on observation of behavior, electroencephalography and 24-hour survival rate. Propofol (12.5–100 mg/kg) improved status epilepticus in a dose-dependent manner, and significantly reduced the number of deaths within 24 hours of lithium-pilocarpine injection. Western blot results showed that, 24 hours after induction of status epilepticus, the levels of N-methyl-D-aspartate receptor 2A and 2B subunits were significantly increased in rat cerebral cortex and hippocampus. Propofol at 50 mg/kg significantly suppressed the increase in N-methyl-D-aspartate receptor 2B subunit levels, but not the increase in N-methyl-D-aspartate receptor 2A subunit levels. The results suggest that propofol can effectively inhibit status epilepticus induced by lithium-pilocarpine. This effect may be associated with downregulation of N-methyl-D-aspartate receptor 2B subunit expression after seizures. PMID:25737709

  20. Precursors and formation of pyrithione and other pyridyl-containing sulfur compounds in drumstick onion, Allium stipitatum

    Czech Academy of Sciences Publication Activity Database

    Kubec, R.; Krejčová, P.; Šimek, Petr; Václavík, L.; Hajšlová, J.; Schraml, Jan

    2011-01-01

    Roč. 59, č. 10 (2011), s. 5763-5770 ISSN 0021-8561 R&D Projects: GA AV ČR IAA400720706 Grant - others:Grant Agency of South Bohemia(CZ) GAJU 067/2010/Z; Grant Agency of South Bohemia(CZ) GAJU 028/2010/P Institutional research plan: CEZ:AV0Z50070508; CEZ:AV0Z40720504 Keywords : Allium stipitatum * S-(2-pyridyl)cysteine N-oxide * marasmin Subject RIV: CE - Biochemistry Impact factor: 2.823, year: 2011

  1. Application of chitosan and its N-heterocyclic derivatives for preconcentration of noble metal ions and their determination using atomic absorption spectrometry.

    Science.gov (United States)

    Azarova, Yu A; Pestov, A V; Ustinov, A Yu; Bratskaya, S Yu

    2015-12-10

    Chitosan and its N-heterocyclic derivatives N-2-(2-pyridyl)ethylchitosan (2-PEC), N-2-(4-pyridyl) ethylchitosan (4-PEC), and N-(5-methyl-4-imidazolyl) methylchitosan (IMC) have been applied in group preconcentration of gold, platinum, and palladium for subsequent determination by atomic absorption spectroscopy (AAS) in solutions with high background concentrations of iron and sodium ions. It has been shown that the sorption mechanism, which was elucidated by XPS, significantly influences the sorption capacity of materials, the efficiency of metal ions elution after preconcentration, and, as a result, the accuracy of metal determination by AAS. We have shown that native chitosan was not suitable for preconcentration of Au(III), if the elution step was used as a part of the analysis scheme. The group preconcentration of Au(III), Pd(II), and Pt(IV) with subsequent quantitative elution using 0.1M HCl/1M thiourea solution was possible only on IMC and 4-PEC. Application of IMC for analysis of the national standard quartz ore sample proved that gold could be accurately determined after preconcentration/elution with the recovery above 80%. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Methyl 2-Benzamido-2-(1H-benzimidazol-1-ylmethoxyacetate

    Directory of Open Access Journals (Sweden)

    Alami Anouar

    2012-09-01

    Full Text Available The heterocyclic carboxylic α-aminoester methyl 2-benzamido-2-(1H-benzimidazol-1-ylmethoxyacetate is obtained by O-alkylation of methyl α-azido glycinate N-benzoylated with 1H-benzimidazol-1-ylmethanol.

  3. Methylation profiling identified novel differentially methylated markers including OPCML and FLRT2 in prostate cancer.

    Science.gov (United States)

    Wu, Yu; Davison, Jerry; Qu, Xiaoyu; Morrissey, Colm; Storer, Barry; Brown, Lisha; Vessella, Robert; Nelson, Peter; Fang, Min

    2016-04-02

    To develop new methods to distinguish indolent from aggressive prostate cancers (PCa), we utilized comprehensive high-throughput array-based relative methylation (CHARM) assay to identify differentially methylated regions (DMRs) throughout the genome, including both CpG island (CGI) and non-CGI regions in PCa patients based on Gleason grade. Initially, 26 samples, including 8 each of low [Gleason score (GS) 6] and high (GS ≥7) grade PCa samples and 10 matched normal prostate tissues, were analyzed as a discovery cohort. We identified 3,567 DMRs between normal and cancer tissues, and 913 DMRs distinguishing low from high-grade cancers. Most of these DMRs were located at CGI shores. The top 5 candidate DMRs from the low vs. high Gleason comparison, including OPCML, ELAVL2, EXT1, IRX5, and FLRT2, were validated by pyrosequencing using the discovery cohort. OPCML and FLRT2 were further validated in an independent cohort consisting of 20 low-Gleason and 33 high-Gleason tissues. We then compared patients with biochemical recurrence (n=70) vs. those without (n=86) in a third cohort, and they showed no difference in methylation at these DMR loci. When GS 3+4 cases and GS 4+3 cases were compared, OPCML-DMR methylation showed a trend of lower methylation in the recurrence group (n=30) than in the no-recurrence (n=52) group. We conclude that whole-genome methylation profiling with CHARM revealed distinct patterns of differential DNA methylation between normal prostate and PCa tissues, as well as between different risk groups of PCa as defined by Gleason scores. A panel of selected DMRs may serve as novel surrogate biomarkers for Gleason score in PCa.

  4. Extraction of U(VI) with unsymmetrical N-methyl-N-octyl alkylamides in toluene

    International Nuclear Information System (INIS)

    Sun Guoxin; Li Yexin; Zhang Zhenwei; Cui Yu; Shandong University, Jinan; Sun Sixiu

    2005-01-01

    Extraction of U(VI) with three new unsymmetrical monoamides, N-methyl-N-octyloctylamide (MOOA), N-methyl-N-octyldecanamide (MODA), and N-methyl-N-octyldodecanamide (MODOA), from nitric acid solution employing toluene as diluent is discussed. The effects of nitric acid, sodium nitrate and extractant concentrations and also the temperature on the distribution ratio have been investigated. The extracted species were studied by IR spectrometry. (author)

  5. Cd(II) and Zn(II) Complexes Containing N,N'-Bidentate N-(Pyridin-2-ylmethylene)cyclopentanamine: Synthesis, Characterisation and Methyl Methacrylate Polymerisation

    Energy Technology Data Exchange (ETDEWEB)

    Song, Yu Jin; Lee, Ha Jun; Lee, Hyo Sun [Kyungpook National University, Daeju (Korea, Republic of)

    2014-09-15

    The reaction between [CdBr{sub 2}·4H{sub 2}O] and anhydrous [ZnCl{sub 2}] with N,N'-bidentate N-(pyridin-2-ylmethylene)- cyclopentanamine (impy) in ethanol yields dimeric [(impy)Cd(μ-Br)Br]2 and monomeric [(impy)ZnCl{sub 2}] complexes, respectively. The X-ray crystal structure of Cd(II) and Zn(II) complexes revealed that the cadmium atom in [(impy)Cd(μ-Br)Br]2 and zinc in [(impy)ZnCl{sub 2}] formed a distorted trigonal–bipyramidal and tetrahedral geometry, respectively. Both complexes showed moderate catalytic activity for the polymerisation of methyl methacrylate (MMA) in the presence of modified methylaluminoxane (MMAO), with polymethylmethacrylate (PMMA) syndiotacticity of about 0.70.

  6. N-methyl-D-aspartic acid receptor agonists

    DEFF Research Database (Denmark)

    Madsen, U; Frydenvang, Karla Andrea; Ebert, B

    1996-01-01

    (R,S)-2-Amino-2-(3-hydroxy-5-methyl-4-isoxazolyl)acetic acid [(R,S)-AMAA, 4] is a potent and selective agonist at the N-methyl-D-aspartic acid (NMDA) subtype of excitatory amino acid receptors. Using the Ugi "four-component condensation" method, the two diastereomers (2R)- and (2S)-2-[3-(benzyloxy......) showed peak affinity for [3H]AMPA receptor sites (IC50 = 72 +/- 13 microM) and was shown to be a more potent inhibitor of [3H]CPP binding (IC50 = 3.7 +/- 1.5 microM) than (S)-AMAA (9) (IC50 = 61 +/- 6.4 microM). Neither enantiomer of AMAA affected [3H]kainic acid receptor binding significantly...

  7. Synthesis and crystal structure of a homoleptic diruthenium complex containing tetra-2-pyridyl-1,4-pyrazine (tppz)

    Energy Technology Data Exchange (ETDEWEB)

    Graf, Marion; Mayer, Peter; Boettcher, Hans-Christian [Muenchen Univ. (Germany). Dept. Chemie

    2017-07-01

    Treatment of hydrated ruthenium(III) chloride with tetra-2-pyridyl-1,4-pyrazine (tppz) in refluxing ethoxyethanol afforded the homoleptic dinuclear complex [(tppz)Ru(μ-tppz)Ru(tppz)]{sup 4+} (1) besides small amounts of the species [Ru(tppz){sub 2}]{sup 2+}. The title complex 1 was obtained as purple crystals and characterized as its hexafluoridophosphate salt by NMR spectroscopy, mass spectrometry and microanalyses. The molecular structure of 1(PF{sub 6}){sub 4} has been established by X-ray crystallography.

  8. Poly[(6-carboxypicolinato-κ3O2,N,O6(μ3-pyridine-2,6-dicarboxylato-κ5O2,N,O6:O2′:O6′dysprosium(III

    Directory of Open Access Journals (Sweden)

    Xu Li

    2009-11-01

    Full Text Available In the title complex, [Dy(C7H3NO4(C7H4NO4]n, one of the ligands is fully deprotonated while the second has lost only one H atom. Each DyIII ion is coordinated by six O atoms and two N atoms from two pyridine-2,6-dicarboxylate and two 6-carboxypicolinate ligands, displaying a bicapped trigonal-prismatic geometry. The average Dy—O bond distance is 2.40 Å, some 0.1Å longer than the corresponding Ho—O distance in the isotypic holmium complex. Adjacent DyIII ions are linked by the pyridine-2,6-dicarboxylate ligands, forming a layer in (100. These layers are further connected by π–π stacking interactions between neighboring pyridyl rings [centroid–centroid distance = 3.827 (3 Å] and C—H...O hydrogen-bonding interactions, assembling a three-dimensional supramolecular network. Within each layer, there are other π–π stacking interactions between neighboring pyridyl rings [centroid–centroid distance = 3.501 (2 Å] and O—H...O and C—H...O hydrogen-bonding interactions, which further stabilize the structure.

  9. Di-μ-iodido-bis(iodido{methyl 4-[(pyridin-2-ylmethylideneamino]benzoate-κ2N,N′}cadmium

    Directory of Open Access Journals (Sweden)

    Tushar S. Basu Baul

    2013-11-01

    Full Text Available The complete binuclear molecule of the title compound, [Cd2I4(C14H12N2O22], is generated by the application of a centre of inversion. The Cd—I bond lengths of the central core are close and uniformly longer than the exocyclic Cd—I bond. The coordination sphere of the CdII atom is completed by two N atoms of a chelating methyl 4-[(pyridin-2-ylmethylideneamino]benzoate ligand, and is based on a square pyramid with the terminal I atom in the apical position. The three-dimensional crystal packing is stabilized by C—H...O and C—H...π interactions, each involving the pyridine ring.

  10. Iron halide mediated atom transfer radical polymerization of methyl methacrylate with N-Alkyl-2-pyridylmethanimine as the ligand

    NARCIS (Netherlands)

    Zhang, H.; Schubert, U.S.

    2004-01-01

    The controlled atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) catalyzed by iron halide/N-(n-hexyl)-2-pyridylmethanimine (NHPMI) is described. The ethyl 2-bromoisobutyrate (EBIB)-initiated ATRP with [MMA]0/[EBIB]0/[iron halide]0/[NHPMI]0 = 150/1/1/2 was better controlled in

  11. Volumetric and acoustical properties of aqueous mixtures of N-methyl-2-hydroxyethylammonium butyrate and N-methyl-2-hydroxyethylammonium pentanoate at T = (298.15 to 333.15) K

    International Nuclear Information System (INIS)

    Li, Yang; Figueiredo, Eduardo J.P.; Santos, Mário J.; Santos, Jaime B.; Talavera-Prieto, Nieves M.C.; Carvalho, Pedro J.; Ferreira, Abel G.M.; Mattedi, Silvana

    2016-01-01

    Highlights: • Density and speed of sound for aqueous mixtures of m2HEAB and m2HEAP were measured. • Apparent molar volumes and apparent molar isentropic compressibilities were calculated. • Excess properties were correlated using Redlich–Kister and rational functions. • The molar compressibility the aqueous mixtures was calculated from the Wadás model. • Appreciable interactions between water and ionic liquid were found. - Abstract: The speed of sound in the protic ionic liquids (PILs) N-methyl-2-hydroxyethylammonium butyrate (m2HEAB) and N-methyl-2-hydroxyethylammonium pentanoate (m2HEAP) was measured at atmospheric pressure, and over the range of temperatures T = (293.15 to 343.15) K. The speed of sound and density of aqueous mixtures of the ionic liquid were also determined throughout the entire concentration range, within the (298.15 to 333.15) K temperature range and at atmospheric pressure. The excess molar volume, excess isentropic compressibility, excess speed of sound, apparent molar volume and apparent molar isentropic compressibility were calculated from the experimental density and speed of sound values. Furthermore, all the properties were correlated with selected analytical functions. The apparent molar volume of aqueous PILs was analysed by Pitzer–Simonson theory. The speed of sound of the PILs was predicted with the Wu et al. model and the molar compressibility of the same PILs and their aqueous mixtures were calculated from Wadás model. The results demonstrate that the molar compressibility calculated from Wadás model is almost a linear function of mole fraction and can be considered as temperature independent for a fixed mole fraction over the whole composition range. The results were analysed and discussed from the structural changes point of view in aqueous medium.

  12. (2,2′-Bipyridine-κ2N,N′iodido(piperidine-1-carbodithioato-κ2S,S′copper(II

    Directory of Open Access Journals (Sweden)

    Le-Qing Fan

    2009-01-01

    Full Text Available In the title compound, [Cu(C6H10NS2I(C10H8N2], the CuII ion is coordinated by one iodide ion, two N atoms of the bipyridine ligand and two S atoms from the piperidinecarbodithioate ligand in a distorted square-pyramidal environment. π–π stacking interactions, with centroid–centroid distances of 3.643 (4 Å, between pyridyl rings of the bipyridyl ligands of neighbouring molecules lead to chains propagating parallel to the a axis.

  13. SYNTHESIS AND CHARACTERIZATION OF NEW THERMALLY STABLE POLYAMIDES BASED ON 2,5-PYRIDINE DICARBOXYLIC ACID AND AROMATIC DIAMINES

    OpenAIRE

    FAGHIHI, KHALIL

    2009-01-01

    Six new thermally stable polyamides 3a-f were synthesized through the polycondensation reaction of 2,5-pyridine dicarboxylic acid 1 with six different derivatives of aromatic diamines 2a-f in amedium consisting of N-methyl-2-pyrrolidone, triphenyl phosphite, calcium chloride and pyridine. The polycondensation reaction produced a series of novel polyamides containing pyridyl moieties in the main chain in high yield with inherent viscosities between 0.50-0.82 dL/g. The resulting polymers were f...

  14. Synthesis of Poly(N-vinyl-2-pyrrolidone-co-methyl methacrylate by Maghnite-H+ a Non-toxic Catalyst

    Directory of Open Access Journals (Sweden)

    Mohamed Benadda

    2014-10-01

    Full Text Available In the present work poly (N-vinyl-2-pyrrolidone-co-methyl methacrylate copolymers were prepared successfully and cleanly by a one step process via cationic copolymerization of N-vinyl-2-pyrrolidone (NVP with methyl methacrylate (MMA, in heterogeneous phase using “Maghnite-H+” (Mag-H+ as catalyst in bulk, Maghnite is a montmorillonite sheet silicate clay exchanged with protons to produce Maghnite-H+. Temperature is varied between 20 and 80 °C. The effects of reaction temperature, amount of Mag-H+ on the yield and the intrinsic viscosity (η were investigated. A typical reaction product of poly (NVP-co- MMA was analyzed by infra red spectroscopy (FTIR and 1H-NMR, 13C-NMR spectroscopy as well as by viscosimetry. © 2014 BCREC UNDIP. All rights reservedReceived: 24th November 2013; Revised: 30th June 2014; Accepted: 8th July 2014How to Cite: Benadda, M., Ferrahi, M.I., Belbachir, M. (2014. Synthesis of Poly(N-vinyl-2-pyrrolidone-co-methyl methacrylate by Maghnite-H+ a Non-toxic Catalyst. Bulletin of Chemical Reaction Engineering & Catalysis, 9 (3: 201-206. (doi: 10.9767/bcrec.9.3.5743.201-206Permalink/DOI: http://dx.doi.org/10.9767/bcrec.9.3.5743.201-206

  15. An irresolute linker: separation, and structural and spectroscopic characterization of the two linkage isomers of a Ru(ii)-(2-(2'-pyridyl)pyrimidine-4-carboxylic acid) complex.

    Science.gov (United States)

    Iengo, E; Demitri, N; Balducci, G; Alessio, E

    2014-08-28

    For the first time the two linkage isomers of a Ru(ii) complex with 2-(2'-pyridyl)pyrimidine-4-carboxylic acid (cppH) - that form in comparable amounts - have been fully characterized individually. The X-ray structure of each isomer is related to its NMR spectrum in solution.

  16. Synthesis of [methyl-[sup 14]C]-N-methylputrescine

    Energy Technology Data Exchange (ETDEWEB)

    Secor, H.V.; Izac, R.R.; Hassam, S.B.; Frisch, A.F. (Philip Morris Research Center, Richmond, VA (United States))

    1994-05-01

    [Methyl-[sup 14]C]-N-methylputrescine was prepared from [[sup 14]C]methylamine hydrochloride in five steps. Reaction of benzaldehyde and [[sup 14]C]methylamine (10 mCi) followed by catalytic hydrogenation yielded [methyl-[sup 14]C]-N-methylbenzylamine. The key step in this process is the alkylation of [methyl-[sup 14]C]-N-methylbenzylamine in aqueous medium with 4-bromobutyronitrile. The radiochemical purity of the final product after two successive catalytic hydrogenations was in excess of 97%. The radiochemical yields in two successive runs were 26 and 38%, based on starting [[sup 14]C]methylamine, with specific activities of 22 and 23 mCi/mmol, respectively. This sequence provides a convenient and efficient regioselective radiosynthesis of [methyl-[sup 14]C]-N-methylputrescine. (author).

  17. Blockade of N-methyl-D-aspartate induced convulsions by 1-aminocyclopropanecarboxylates

    International Nuclear Information System (INIS)

    Skolnick, P.; Marvizon, J.C.G.; Jackson, B.W.; Monn, J.A.; Rice, K.C.; Lewin, A.H.

    1989-01-01

    1-Aminocyclopropanecarboxylic acid is a potent and selective ligand for the glycine modulatory site on the N-methyl-D-aspartate receptor complex. This compound blocks the convulsions and deaths produced by N-methyl-D-aspartate in a dose dependent fashion. In contrast, 1-aminocyclopropanecarboxylic acid does not protect mice against convulsions induced by pentylenetetrazole, strychnine, bicuculline, or maximal electroshock, and does not impair motor performance on either a rotarod or horizontal wire at doses of up to 2 g/kg. The methyl- and ethyl- esters of 1-aminocyclopropanecarboxylic acid are 5- and 2.3-fold more potent, respectively, than the parent compound in blocking the convulsant and lethal effects of N-methyl-D-aspartate. However, these esters are several orders of magnitude less potent than 1-aminocyclopropanecarboxylic acid as inhibitors of strychnine-insensitive [ 3 H]glycine binding, indicating that conversion to the parent compound may be required to elicit an anticonvulsant action

  18. 11C-labelling of the analgesic Tramadol and its major metabolites by selective O- and N-methylation

    International Nuclear Information System (INIS)

    Gail, R.; Coenen, H.H.; Hamacher, K.; Stoecklin, G.

    1992-01-01

    For in vivo pharmacokinetic studies with PET, the analgesic Tramadol(1-(3-methoxyphenyl)-2-dimethylaminomethyl-cyclohexan-1-ol) and its major O- and N-desmethylated metabolites M1 and M2 were labelled with carbon-11. Starting with the corresponding desmethyl precursors, [O-methyl- 11 C]Tramadol and racemic[N-methyl- 11 C]Tramadol were prepared by methylation with n.c.a. [ 11 C]methyl iodide in DMSO with radiochemical yields of 85 and 90%, respectively. Specific n.c.a. N-methylation of bis-desmethyl-Tramadol (M5) was achieved with 90% radiochemical yield. However, a selective O-methylation of M5 was not possible even with an excess of NaOH, and only 70% of [O-methyl- 11 C]M2 was obtained. Quaternization of Tramadol or M1 was >15 times slower than O-methylation, and was only observed in the presence of added CH 3 I carrier. (author)

  19. Structure-activity relationship analysis of cytotoxic cyanoguanidines: selection of CHS 828 as candidate drug

    Directory of Open Access Journals (Sweden)

    Gullbo Joachim

    2009-06-01

    Full Text Available Abstract Background N-(6-(4-chlorophenoxyhexyl-N'-cyano-N''-4-pyridyl guanidine (CHS 828 is the first candidate drug from a novel group of anti-tumour agents – the pyridyl cyanoguanidines, shown to be potent compounds interfering with cellular metabolism (inhibition of nicotinamide phosphoribosyl transferase and NF-κB signalling. Substituted cyanoguanidines are also found in anti-hypertensive agents such as the potassium channel opener pinacidil (N-cyano-N'-(4-pyridyl-N''-(1,2,2-trimethylpropylguanidine and histamine-II receptor antagonists (e.g. cimetidine, N-cyano-N'-methyl-N''-[2-[[(5-methylimidazol-4-yl]methyl]thio]ethylguanidine. In animal studies, CHS 828 has shown very promising activity, and phase I and II studies resulted in further development of a with a water soluble prodrug. Findings To study the structural requirements for cyanoguanidine cytotoxicity a set of 19 analogues were synthesized. The cytotoxic effects were then studied in ten cell lines selected for different origins and mechanisms of resistance, using the fluorometric microculture cytotoxicity assay (FMCA. The compounds showed varying cytotoxic activity even though the dose-response curves for some analogues were very shallow. Pinacidil and cimetidine were found to be non-toxic in all ten cell lines. Starting with cyanoguanidine as the crucial core it was shown that 4-pyridyl substitution was more efficient than was 3-pyridyl substitution. The 4-pyridyl cyanoguanidine moiety should be linked by an alkyl chain, optimally a hexyl, heptyl or octyl chain, to a bulky end group. The exact composition of this end group did not seem to be of crucial importance; when the end group was a mono-substituted phenyl ring it was shown that the preferred position was 4-substitution, followed by 3- and, finally, 2-substitution as the least active. Whether the substituent was a chloro, nitro or methoxy substituent seemed to be of minor importance. Finally, the activity patterns in the

  20. 2,2′-(Diselane-1,2-diyldinicotinamide N,N′-dimethylformamide disolvate

    Directory of Open Access Journals (Sweden)

    Aixia Feng

    2010-05-01

    Full Text Available The asymmetric unit of the title compound, C12H10N4O2Se2·2C3H7NO, contains two solvent molecules and two half molecules of the dinicotinamide, each of which sits on a center of symmetry passing through the middle of the Se—Se bond. In each molecule, the two pyridyl groups and diseleno group are approximately coplanar (r.m.s. deviations from planarity for all non-H atoms = 0.011 and 0.008 Å in the two molecules. Intermolecular N—H...O hydrogen bonds stablilize the crystal packing.

  1. NMR and computer modelling conformational study of N-benzyl, N-n-propyl (2-methyl-3-nitrophenyl)acetamide

    International Nuclear Information System (INIS)

    Nicolle, E.; Benoit-Guyod, M.; Namil, A.; Cussac, M.; Leclerc, G.; Maldivi, P.

    1995-01-01

    The conformation of N-benzyl-N-n-propyl (2-methyl-3-nitrophenyl) acetamide 1 in dimethyl sulfoxide (DMSO-d 6 ) or chloroform (CDCL 3 ) solution was studied using 1 H and 13 CNMR analysis. In solution, 1 existed as two distinct Z and E isomers, which could not be separated at laboratory temperature. Both conformations were in equivalent proportions in chloroform whereas in a polar solvent (DMSO), the conformation Z was more usual with the aromatic rings in a transposition. Major and minor rotation isomers were assigned form the '1H and 13 C NMR chemical shifts determined at 293 K. Separate treatment of signals displayed by two different methylene groups gave comparable activation parameters (ΔG ∼ 16 kcal/mol). Conformational analysis and measurement of the rotational barrier between the E and Z conformers by molecular modeling (Sybyl program) were performed. (authors). 14 refs., 8 figs

  2. Protective effects of folic acid on DNA damage and DNA methylation levels induced by N-methyl- N'-nitro- N-nitrosoguanidine in Kazakh esophageal epithelial cells.

    Science.gov (United States)

    Chen, Y; Feng, H; Chen, D; Abuduwaili, K; Li, X; Zhang, H

    2018-01-01

    The protective effects of folic acid on DNA damage and DNA methylation induced by N-methyl- N'-nitro- N-nitrosoguanidine (MNNG) in Kazakh esophageal epithelial cells were investigated using a 3 × 3 factorial design trial. The cells were cultured in vitro and exposed to media containing different concentrations of folic acid and MNNG, after which growth indices were detected. DNA damage levels were measured using comet assays, and genome-wide DNA methylation levels (MLs) were measured using high-performance liquid chromatography. The DNA methylation of methylenetetrahydrofolate reductase (MTHFR) and folate receptor- α (FR α) genes was detected by bisulfite sequencing polymerase chain reaction (PCR). The results showed significant increases in tail DNA concentration, tail length, and Olive tail moment ( p methylation frequencies of MTHFR and FR α genes. In particular, significant differences were observed in the promoter regions of both genes ( p methylation in Kazakh esophageal epithelial cells upon MNNG exposure. Thus, sufficient folic acid levels could play a protective role against the damage induced by this compound.

  3. Determination of 5-hydroxy-N-methyl-2-pyrrolidone and 2-hydroxy-N-methylsuccinimide in human plasma and urine using liquid chromatography-electrospray tandem mass spectrometry.

    Science.gov (United States)

    Carnerup, M A; Akesson, B; Jönsson, B A

    2001-09-15

    A method for simultaneous determination of 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP) and 2-hydroxy-N-methylsuccinimide (2-HMSI) was developed. These compounds are metabolites from N-methyl-2-pyrrolidone (NMP), a powerful and widely used organic solvent. 5-HNMP and 2-HMSI were purified from plasma and urine by solid-phase extraction using Isolute ENV+ columns, and analysed by liquid chromatography coupled to a mass spectrometer fitted with an atmospheric pressure turbo ion spray ionisation interface in the positive ion mode. The method was validated for plasma and urine concentrations from 0.12 to 25 microg/ml. The recoveries for 5-HNMP and 2-HMSI in plasma were 99 and 98%, respectively, and in urine 111 and 106%, respectively. For 5-HNMP and 2-HMSI, the within-day precision in plasma was 1-4 and 3-6%, respectively, and in urine 2-12 and 3-10%, respectively. The corresponding data for the between-day precision was 5 and 3-6%, respectively, and 4-6 and 7-8%, respectively. The detection limit for 5-HNMP was 4 ng/ml in plasma and 120 ng/ml in urine. For 2-HMSI, it was 5 ng/ml in plasma and 85 ng/ml in urine. The method is applicable for analysis of plasma and urine samples from workers exposed to NMP.

  4. A new prearranged tripodant ligand ¤N,N',N''¤-trimethyl-¤N,N',N''¤tris(3-pyridyl)-1,3,5-benzene tricarboxamide is easily obtained via the ¤N¤-methyl amide effect

    DEFF Research Database (Denmark)

    Jørgensen, M.; Krebs, Frederik C

    2001-01-01

    The N-methyl amide cis generating effect has been utilised to create a new prearranged tripodant ligand in two synthetic steps from benzene-1,3,5-tricarbuxylic acid. Crystals of rhc ligand itself and of complexes with metal sails such as silver(I) triflate, copper(I) and copper(II) chloride...

  5. Candida Rugosa Lipase-catalyzed Kinetic Resolution of 3-(Isobutyryloxy)methyl 4-[2-(Difluoromethoxy)phenyl]-2-methyl-5,5-dioxo-1,4-dihydrobenzothieno[3,2-b]pyridine-3-carboxylate

    NARCIS (Netherlands)

    Sobolev, A.; Zhalubovskis, R.; Franssen, M.C.R.; Vigante, B.; Chekavichus, B.; Duburs, G.; Groot, de Æ.

    2004-01-01

    The lipase-catalyzed kinetic resolution of 3-(isobutyryloxy)methyl 4-[2-(difluoromethoxy)phenyl]-2-methyl-5,5-dioxo-1,4-dihydrobenzothieno[3,2-b]pyridine-3-carboxylate has been performed. The most enantioselective reaction (E = 28) was transesterification with n-butanol in water-saturated toluene at

  6. Studies on coordination chemistry and bioactivity of metal complexes of a bidentate NN schiff base, (2-pyridyl-methylene)(phenyl) hydrazine, produced from the condensation of pyridine-2-carboxaldehyde with phenylhydrazine

    International Nuclear Information System (INIS)

    Tarafder, M.T.H.; Zakaria, C.M.; Idrus, Razmi Mohd; Crouse, Karen A.; Ali, A.M.; Yamin, B.M.; Fun, H.-K.

    2003-07-01

    A bidentate Schiff base, (2-pyridyl-methylene)(phenyl) hydrazine, with NN donor sequence, was isolated from the condensation of pyridine-2-carboxaldehyde with phenylhydrazine in ethanol. Metal complexes of this ligand with Ni(II), Zn(It), and Cu(n) ions were synthesized and characterized by a variety of physico-chemical techniques. The structure of the Schiff base was solved by X-ray diffraction studies, which indicated that it was monoclinic with a space group of C2/c. The complexes were all four coordinated. The compounds were tested against four pathogenic bacteria and fungi. The nickel complex, [Ni(NN) 2 Cl 2 ], in particular, was found to be active against all the fungi tested. The complexes were however inactive against leukemic cell lines (CEM-SS). (author)

  7. Short communication. N-(2-chloro-4-pyridyl)-N-phenylurea (4-CPPU) enhances in vitro direct shoot organogenesis of Citrus aurantium L. epicotyl segments compared to other commonly used cytokinins

    Energy Technology Data Exchange (ETDEWEB)

    Roussos, P. A.; Dimitriou, G.; Voloudakis, A. E.

    2011-07-01

    The effect of three concentrations of five different cytokinins, i.e. 6-benzylamino purine, 2-isopentyl adenine, kinetin (Kin), thidiazuron and N-(2-chloro-4-pyridyl)-N-phenylurea (4-CPPU), was evaluated on the in vitro direct shoot organogenesis of epicotyl explants of sour orange (Citrus aurantium L.). The basal medium used was that of Murashige and Tucker and epicotyl explants were incubated in medium supplemented with the prementioned cytokinins for 45 days. The addition of Kin and 4-CPPU in the medium enhanced the direct shoot organogenesis of sour orange epicotyl segments. The concentration of each of these two cytokinins which gave the best results, was combined with indole-3-acetic acid (IAA) or {alpha}-naphthalene acetic acid ({alpha}-NAA) at concentrations ranging from 0.01 mg L{sup -}1 to 0.2 mg L{sup -}1. The inclusion of IAA at 0.2 mg L{sup -}1 in the medium with 4-CPPU at 0.05 mg L{sup -}1 resulted in 100% successful direct shoot organogenesis, while the combination of Kin at 0.25 mg L{sup -}1 with IAA or {alpha}-NAA each at 0.01 mg L{sup -}1 presented equally high organogenesis percentages (91.7%). The incubation of the produced shoots, in medium supplemented with either indole-3-butyric acid or {alpha}-NAA resulted in high rooting percentages (up to 90%) and the rooted explants were successfully acclimatized under mist (85%). Although 4-CPPU has been used in in vitro culture of various species, this is the first report on its use in the direct shoot organogenesis of citrus species and could be of great value in citrus genetic transformation protocols using epicotyl segments, since this cytokinin resulted in the absolute organogenesis percentage. (Author) 20 refs.

  8. Cadmium inhibits repair of UV-, methyl methanesulfonate- and N-methyl-N-nitrosourea-induced DNA damage in Chinese hamster ovary cells

    International Nuclear Information System (INIS)

    Fatur, Tanja; Lah, Tamara T.; Filipic, Metka

    2003-01-01

    The co-genotoxic effects of cadmium are well recognized and it is assumed that most of these effects are due to the inhibition of DNA repair. We used the comet assay to analyze the effect of low, non-toxic concentrations of CdCl 2 on DNA damage and repair-induced in Chinese hamster ovary (CHO) cells by UV-radiation, by methyl methanesulfonate (MMS) and by N-methyl-N-nitrosourea (MNU). The UV-induced DNA lesions revealed by the comet assay are single-strand breaks which are the intermediates formed during nucleotide excision repair (NER). In cells exposed to UV-irradiation alone the formation of DNA strand breaks was rapid, followed by a fast rejoining phase during the first 60 min after irradiation. In UV-irradiated cells pre-exposed to CdCl 2 , the formation of DNA strand breaks was significantly slower, indicating that cadmium inhibited DNA damage recognition and/or excision. Methyl methanesulfonate and N-methyl-N-nitrosourea directly alkylate nitrogen and oxygen atoms of DNA bases. The lesions revealed by the comet assay are mainly breaks at apurinic/apyrimidinic (AP) sites and breaks formed as intermediates during base excision repair (BER). In MMS treated cells the initial level of DNA strand breaks did not change during the first hour of recovery; thereafter repair was detected. In cells pre-exposed to CdCl 2 the MMS-induced DNA strand breaks accumulated during the first 2 h of recovery, indicating that AP sites and/or DNA strand breaks were formed but that further steps of BER were blocked. In MNU treated cells the maximal level of DNA strand breaks was detected immediately after the treatment and the breaks were repaired rapidly. In CdCl 2 pre-treated cells the formation of MNU-induced DNA single-strand breaks was not affected, while the repair was slower, indicating inhibition of polymerization and/or the ligation step of BER. Cadmium thus affects the repair of UV-, MMS- and MNU-induced DNA damage, providing further evidence, that inhibition of DNA repair

  9. UV–vis spectroscopic study of room temperature ionic liquid–water mixtures: N,N-diethyl-N-methyl-N-(2-methoxyethyl) ammonium tetrafluoroborate

    International Nuclear Information System (INIS)

    Aono, Masami; Imai, Yusuke; Abe, Hiroshi; Matsumoto, Hitoshi; Yoshimura, Yukihiro

    2012-01-01

    Highlights: ► Number of absorption peaks in [DEME][BF 4 ]-H 2 O depends on H 2 O concentrations. ► At 90–96 mol% H 2 O, low optical transmittance shows on UV-visible region. ► Relatively soft glass appears only 90–96 mol% region by slow cooling. - Abstract: N,N-diethyl-N-methyl-N-(2-methoxyethyl) ammonium tetrafluoroborate, [DEME][BF 4 ], and H 2 O mixtures were investigated in optical properties by UV–visible spectroscopy. The concentration region of H 2 O in the mixtures was 0–100 mol%. At room temperature, the mixtures of H 2 O exhibit absorption peaks at around 280 nm and 750 nm, which depend on H 2 O concentrations. At 90–95 mol% H 2 O, the optical transmittance decreased over the whole region of UV–visible light. In X-ray diffraction, correlation over the medium-range such as network-forming materials develops at 90–95 mol%. Also, in quenched glass, low glass transition temperature appeared at these H 2 O concentrations. The specific glass is induced by different molecular aggregation in liquid. Therefore, an optical anomaly is connected with the specific water network over the medium-range order.

  10. Multi-signalling cation sensing behaviour of a bis(pyridin-2-yl methyl)aniline based hetarylazo dye

    International Nuclear Information System (INIS)

    Kaur, Paramjit; Sareen, Divya; Kaur, Mandeep; Singh, Kamaljit

    2013-01-01

    Graphical abstract: The chromogenic and electrochemical behaviour of bis(pyridine-2-yl methyl)aniline based hetarylazo dye gets perturbed in the presence of cations, most effective being Cu 2+ . The conversion of ICT to ICT/MLCT is witnessed by TD-DFT calculations. -- Highlights: •Cation sensing of hetarylazo dye based upon visual, absorption and electrochemical changes is described. •Sensing mechanism is based upon perturbation in intramolecular charge-transfer upon interaction with cations. •Sensing protocol is supported by 1 H NMR studies as well as theoretical calculations. •Hetarylazo dye acts as a multichannel sensor. •Response of the dye towards various cations has also been explored in acidic pH window. -- Abstract: We investigated the cation sensing behaviour of a bis(pyridin-2-yl methyl)aniline appended hetarylazo dye via chromogenic and electrochemical transduction channels. The binding pocket constituting both the pyridyl as well as aniline nitrogen atoms acts as recognition site for the cations and consequent perturbation in the intramolecular charge-transfer prevailing in the dye results in the chromogenic response manifested in the form of hypsochromic shift in the intramolecular charge-transfer band and the attendant naked-eye color changes. The dye exhibits significant changes in its electrochemical behaviour in the presence of cations. The experimental results are also rationalized by time-dependent density functional theory (TD-DFT) calculations

  11. Poly[mu2-(N-hydroxypyridine-2-carboxamidine)-mu2-nitrato-silver(I)].

    Science.gov (United States)

    Cui, Ai-Li; Han, Peng; Yang, Hui-Juan; Wang, Ru-Ji; Kou, Hui-Zhong

    2007-12-01

    In the title complex, [Ag(NO3)(C6H7N3O)]n or [Ag(NO3)(pyaoxH2)] (pyaoxH2 is N-hydroxypyridine-2-carboxamidine), the Ag+ ion is bridged by the pyaoxH2 ligands and nitrate anions, giving rise to a two-dimensional molecular structure. Each pyaoxH2 ligand coordinates to two Ag+ ions using its pyridyl and carboxamidine N atoms, and the OH and the NH2 groups are uncoordinated. Each nitrate anion uses two O atoms to coordinate to two Ag+ ions. The Ag...Ag separation via the pyaoxH2 bridge is 2.869 (1) A, markedly shorter than that of 6.452 (1) A via the nitrate bridge. The two-dimensional structure is fishscale-like, and can be described as pyaoxH2-bridged Ag2 nodes that are further linked by nitrate anions. Hydrogen bonding between the amidine groups and the nitrate O atoms connects adjacent layers into a three-dimensional network.

  12. Diaquabis[N,N′-(ethane-1,2-diylbis(isonicotinamide-κN]bis(hydrogen phthalato-κOnickel(II hexahydrate

    Directory of Open Access Journals (Sweden)

    Torél Beard

    2016-07-01

    Full Text Available In the title solvated coordination complex, [Ni(C8H5O42(C14H14N4O22(H2O2]·6H2O, the NiII cation is octahedrally coordinated by trans carboxylate O-atom donors from two crystallographically distinct monodentate hydrogen phthalate (Hpht− ligands, two trans aqua ligands, and trans pyridyl N-atom donors from two crystallographically distinct N,N′-(ethane-1,2-diylbis(isonicotinamide (ebin ligands. Extensive O—H...O and O—H...N hydrogen-bonding patterns involving the water molecules of crystallization anchor neighboring coordination complexes into a three-dimensional network.

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

    Science.gov (United States)

    Eng, Julien; Daniel, Chantal

    2015-10-29

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

  14. N-acetyltransferase-dependent activation of 2-hydroxyamino-1-methyl-6-phenylimidazo[4,5-b]pyridine: formation of 2-amino-1-methyl-6-(5-hydroxy)phenylimidazo [4,5-b]pyridine, a possible biomarker for the reactive dose of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine

    DEFF Research Database (Denmark)

    Frandsen, Henrik Lauritz; Alexander, J.

    2000-01-01

    2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is a mutagenic and carcinogenic heterocyclic amine formed during ordinary cooking. PhIP is metabolically activated to the ultimate mutagenic metabolite by CYP P450-mediated N-hydroxylation followed by phase II esterification, Incubation of N...

  15. Cocrystals of 6-methyl-2-thiouracil: presence of the acceptor-donor-acceptor/donor-acceptor-donor synthon.

    Science.gov (United States)

    Hützler, Wilhelm Maximilian; Egert, Ernst

    2015-03-01

    The results of seven cocrystallization experiments of the antithyroid drug 6-methyl-2-thiouracil (MTU), C(5)H(6)N(2)OS, with 2,4-diaminopyrimidine, 2,4,6-triaminopyrimidine and 6-amino-3H-isocytosine (viz. 2,6-diamino-3H-pyrimidin-4-one) are reported. MTU features an ADA (A = acceptor and D = donor) hydrogen-bonding site, while the three coformers show complementary DAD hydrogen-bonding sites and therefore should be capable of forming an ADA/DAD N-H...O/N-H...N/N-H...S synthon with MTU. The experiments yielded one cocrystal and six cocrystal solvates, namely 6-methyl-2-thiouracil-2,4-diaminopyrimidine-1-methylpyrrolidin-2-one (1/1/2), C(5)H(6)N(2)OS·C(4)H(6)N(4)·2C(5)H(9)NO, (I), 6-methyl-2-thiouracil-2,4-diaminopyrimidine (1/1), C(5)H(6)N(2)OS·C(4)H(6)N(4), (II), 6-methyl-2-thiouracil-2,4-diaminopyrimidine-N,N-dimethylacetamide (2/1/2), 2C(5)H(6)N(2)OS·C(4)H(6)N(4)·2C(4)H(9)NO, (III), 6-methyl-2-thiouracil-2,4-diaminopyrimidine-N,N-dimethylformamide (2/1/2), C(5)H(6)N(2)OS·0.5C(4)H(6)N(4)·C(3)H(7)NO, (IV), 2,4,6-triaminopyrimidinium 6-methyl-2-thiouracilate-6-methyl-2-thiouracil-N,N-dimethylformamide (1/1/2), C(4)H(8)N(5)(+)·C(5)H(5)N(2)OS(-)·C(5)H(6)N(2)OS·2C(3)H(7)NO, (V), 6-methyl-2-thiouracil-6-amino-3H-isocytosine-N,N-dimethylformamide (1/1/1), C(5)H(6)N(2)OS·C(4)H(6)N(4)O·C(3)H(7)NO, (VI), and 6-methyl-2-thiouracil-6-amino-3H-isocytosine-dimethyl sulfoxide (1/1/1), C(5)H(6)N(2)OS·C(4)H(6)N(4)O·C(2)H(6)OS, (VII). Whereas in cocrystal (I) an R(2)(2)(8) interaction similar to the Watson-Crick adenine/uracil base pair is formed and a two-dimensional hydrogen-bonding network is observed, the cocrystals (II)-(VII) contain the triply hydrogen-bonded ADA/DAD N-H...O/N-H...N/N-H...S synthon and show a one-dimensional hydrogen-bonding network. Although 2,4-diaminopyrimidine possesses only one DAD hydrogen-bonding site, it is, due to orientational disorder, triply connected to two MTU molecules in (III) and (IV).

  16. Four thiophene-pyridyl-amide-based Zn{sup II}/Cd{sup II} coordination polymers: Assembly, structures, photocatalytic properties and fluorescent recognition for Fe{sup 3+}

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiu-Li; Wu, Xiao-Mei; Liu, Guo-Cheng; Li, Qiao-Min; Lin, Hong-Yan; Wang, Xiang

    2017-05-15

    By tuning metal ions and combining with different dicarboxylates, four new semi-rigid thiophene-bis-pyridyl-bis-amide-based coordination polymers, namely, [Zn(3-bptpa)(1,3-BDC)]·DMA·2H{sub 2}O (1), [Zn(3-bptpa)(5-MIP)] (2), [Cd(3-bptpa)(1,3-BDC)]·2H{sub 2}O (3) and [Cd(3-bptpa)(5-MIP)]·4H{sub 2}O (4) (3-bptpa=N,N′-bis(pyridine-3-yl)thiophene-2,5-dicarboxamide, 1,3-H{sub 2}BDC=1,3-benzenedicarboxylic acid, 5-H{sub 2}MIP=5-methylisophthalic acid, DMA=N,N-dimethylacetamide), were solvothermally/hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction analyses, IR spectra, UV–vis diffuse-reflectance spectra (DRS), powder X-ray diffraction (PXRD) and thermal gravimetric analyses (TG). The structural analysis reveals that Zn-complexes 1 and 2 are similar 2D networks. While Cd-complexes 3 and 4 exhibit similar 2-fold interpenetrating 3D α-Po frameworks with the (4{sup 12}·6{sup 3}) topology. The photocatalytic properties for the degradation of methylene blue (MB) under ultraviolet light irradiation of the title complexes have been investigated in detail. Furthermore, the luminescent sensing behaviors for metal cations of 1–4 have been studied, the results indicate that 3 is an excellent fluorescent probe, with high sensitivity, selectivity, and simple regeneration, for environmentally relevant Fe{sup 3+} ions. - Graphical abstract: Four Zn{sup II}/Cd{sup II} coordination polymers with a thiophene-pyridyl-amide ligand have been prepared. The photocatalytic activities and fluorescent sensing properties for metal ions of the title complexes have been investigated. - Highlights: • Four coordination polymers with thiophene-pyridyl-amide ligands have been obtained. • The central metal ions play an important role in the formation of the frameworks. • The photoluminescent sensing and the photocatalytic properties have been investigated.

  17. 4-Methyl-N-(1-methyl-1H-indazol-5-yl)benzene­sulfonamide

    Science.gov (United States)

    Chicha, Hakima; Oulemda, Bassou; Rakib, El Mostapha; Saadi, Mohamed; El Ammari, Lahcen

    2013-01-01

    In the title compound, C15H15N3O2S, the fused ring system is close to planar, the largest deviation from the mean plane being 0.030 (2) Å, and makes a dihedral angle of 48.84 (9)° with the benzene ring belonging to the methyl­benzene­sulfonamide moiety. In the crystal, mol­ecules are ­connected through N—H⋯N hydrogen bonds and weak C—H⋯O contacts, forming a two-dimensional network parallel to (001). PMID:24427093

  18. An ion-current mutant of Paramecium tetraurelia with defects in the primary structure and post-translational N-methylation of calmodulin

    International Nuclear Information System (INIS)

    Wallen-Friedman, M.A.

    1988-01-01

    My work on pantophobiac A 2 (pntA 2 ), a behavioral mutant of Paramecium tetraurelia, suggest that the Ca ++ -binding protein calmodulin (CaM), and post-translation N-methylation of CaM, are important for Ca ++ -related ion-current function. Calmodulin from wild-type Paramecium has two sites of lysine-N-methylation. Both of these sites are almost fully methylated in vivo; thus wild-type calmodulin is a poor substrate for N-methylation in vitro. In contrast, pntA/ 2 CaM can be heavily N-methylated in vitro, suggesting that the mutant calmodulin is under-methylated in vivo. Amino-acid composition analysis showed that CaM lysine 115 is undermethylated in pntA 2 . Once pntA 2 CaM is N-methylated, the [methyl- 3 H] group does not turn over in either wild-type or pntA 2 cytoplasmic fractions. The methylating enzymes in pntA 2 high-speed supernatant fractions are active, but may be less robust than those of the wild type, suggesting a possible control of these enzymes by CaM

  19. Binding of [3H]MSX-2 (3-(3-hydroxypropyl)-7-methyl-8-(m-methoxystyryl)-1-propargylxanthine) to rat striatal membranes--a new, selective antagonist radioligand for A(2A) adenosine receptors.

    Science.gov (United States)

    Müller, C E; Maurinsh, J; Sauer, R

    2000-01-01

    The present study describes the preparation and binding properties of a new, potent, and selective A(2A) adenosine receptor (AR) antagonist radioligand, [3H]3-(3-hydroxypropyl)-7-methyl-8-(m-methoxystyryl)-1-propargy lxanth ine ([3H]MSX-2). [3H]MSX-2 binding to rat striatal membranes was saturable and reversible. Saturation experiments showed that [3H]MSX-2 labeled a single class of binding sites with high affinity (K(d)=8.0 nM) and limited capacity (B(max)=1.16 fmol.mg(-1) of protein). The presence of 100 microM GTP, or 10 mM magnesium chloride, respectively, had no effect on [3H]MSX-2 binding. AR agonists competed with the binding of 1 nM [3H]MSX-2 with the following order of potency: 5'-N-ethylcarboxamidoadenosine (NECA)>2-[4-(carboxyethyl)phenylethylamino]-5'-N-ethylcarboxami doaden osine (CGS-21680)>2-chloroadenosine (2-CADO)>N(6)-cyclopentyladenosine (CPA). AR antagonists showed the following order of potency: 8-(m-bromostyryl)-3, 7-dimethyl-1-propargylxanthine (BS-DMPX)>1, 3-dipropyl-8-cyclopentylxanthine (DPCPX)>(R)-5, 6-dimethyl-7-(1-phenylethyl)-2-(4-pyridyl)-7H-pyrrolo[2, 3-d]pyrimidine-4-amine (SH-128)>3,7-dimethyl-1-propargylxanthine (DMPX)>caffeine. The K(i) values for antagonists were in accordance with data from binding studies with the agonist radioligand [3H]CGS21680, while agonist affinities were 3-7-fold lower. [3H]MSX-2 is a highly selective A(2A) AR antagonist radioligand exhibiting a selectivity of at least two orders of magnitude versus all other AR subtypes. The new radioligand shows high specific radioactivity (85 Ci/mmol, 3150 GBq/mmol) and acceptable nonspecific binding at rat striatal membranes of 20-30%, at 1 nM.

  20. PRMT1-mediated arginine methylation controls ATXN2L localization

    Energy Technology Data Exchange (ETDEWEB)

    Kaehler, Christian; Guenther, Anika; Uhlich, Anja; Krobitsch, Sylvia, E-mail: krobitsc@molgen.mpg.de

    2015-05-15

    Arginine methylation is a posttranslational modification that is of importance in diverse cellular processes. Recent proteomic mass spectrometry studies reported arginine methylation of ataxin-2-like (ATXN2L), the paralog of ataxin-2, a protein that is implicated in the neurodegenerative disorder spinocerebellar ataxia type 2. Here, we investigated the methylation state of ATXN2L and its significance for ATXN2L localization. We first confirmed that ATXN2L is asymmetrically dimethylated in vivo, and observed that the nuclear localization of ATXN2L is altered under methylation inhibition. We further discovered that ATXN2L associates with the protein arginine-N-methyltransferase 1 (PRMT1). Finally, we showed that neither mutation of the arginine–glycine-rich motifs of ATXN2L nor methylation inhibition alters ATXN2L localization to stress granules, suggesting that methylation of ATXN2L is probably not mandatory. - Highlights: • ATXN2L is asymmetrically dimethylated in vivo. • ATXN2L interacts with PRMT1 under normal and stress conditions. • PRMT1-mediated dimethylation of ATXN2L controls its nuclear localization. • ATXN2L localization to stress granules appears independent of its methylation state.

  1. Manganese(I-Based CORMs with 5-Substituted 3-(2-PyridylPyrazole Ligands

    Directory of Open Access Journals (Sweden)

    Ralf Mede

    2017-01-01

    Full Text Available The reaction of [(OC5MnBr] with substituted 3-(2-pyridylpyrazoles 2-PyPzRH (1a-l in methanol or diethyl ether yields the yellow to orange manganese(I complexes [(OC3Mn(Br(2-PyPzRH] (2a-l, the substituents R being phenyl (a, 1-naphthyl (b, 2-anthracenyl (c, 1-pyrenyl (d, 4-bromophenyl (e, 3-bromophenyl (f, duryl (g, 2-pyridyl (h, 2-furanyl (i, 2-thienyl (j, ferrocenyl (k, and 1-adamantyl (l. The carbonyl ligands are arranged facially, leading to three chemically different CO ligands due to different trans-positioned Lewis donors. The diversity of the substituent R demonstrates that this photoCORM backbone can easily be varied with a negligible influence on the central (OC3MnBr fragment, because the structural parameters and the spectroscopic data of this unit are very similar for all these derivatives. Even the ferrocenyl complex 2k shows a redox potential for the ferrocenyl subunit which is identical to the value of the free 5-ferrocenyl-3-(2-pyridylpyrazole (1k. The ease of variation of the starting 5-substituted 3-(2-pyridylpyrazoles offers a modular system to attach diverse substituents at the periphery of the photoCORM complex.

  2. Calorimetric determination of enthalpies for the proton ionization of N,N-bis[2-hydroxyethyl]-2-aminoethanesulfonic acid (BES) and N-tris[hydroxymethyl]methyl-2-aminoethanesulfonic acid (TES) in water-methanol mixtures

    International Nuclear Information System (INIS)

    Bulos, B.N.; Jumean, F.H.

    2004-01-01

    The enthalpies of proton ionization of the biochemical buffers N,N-bis[2-hydroxyethyl]-2-aminoethanesulfonic acid (BES) and N-tris[hydroxymethyl]methyl-2-aminoethanesulfonic acid (TES) were obtained in water-methanol mixtures in which the methanol mole fraction (X m ) varied in the range 0-0.36. For both buffers, ionization enthalpy for the first proton (ΔH 1 ) was small in all solvent media. However, upon addition of methanol, ΔH 2 increased steadily from 22.2 to a maximum of 27.2 kJ mol -1 for BES, whereas for TES it varied from 30.0 to 32.4, with a minimum of 28.6 kJ mol -1 at X m =0.123. It is noteworthy that this solvent composition lies within the region of maximum structure enhancement of water by methanol. The results were interpreted in terms of methanol-water interactions

  3. Propionyl-l-carnitine: Labelling in the N-methyl position with Carbon-11 and pharmacokinetic studies in rats

    International Nuclear Information System (INIS)

    Davenport, Raymond J.; Law, Marilyn P.; Pike, Victor W.; Osman, Safiye; Poole, Keith G.

    1995-01-01

    The prospective therapeutic, propionyl-l-carnitine, was labelled in the N-methyl position with the positron-emitter, carbon-11 (t (1(2)) = 20.4 min), with a view to studying its pharmacokinetics in humans using PET. Labelling was achieved by methylating nor-propionyl-l-carnitine hydrochloride with no-carrier-added [ 11 C]iodomethane (produced from cyclotron-produced [ 11 C]carbon dioxide) in ethanol in the presence of 1,2,2,6,6,-pentamethylpiperidine. HPLC of the reaction mixture on a strong cation exchange column provided high purity [N-methyl- 11 C]propionyl-l-carnitine in 62% radiochemical yield (decay-corrected from [ 11 C]iodomethane), ready for intravenous administration within 35 min from the end of radionuclide production. [N-methyl- 11 C]Propionyl-l-carnitine, given intravenously to rats, cleared rapidly from plasma. A slow uptake of radioactivity into myocardium and striated muscle was observed. In plasma, unchanged tracer represented 84% of the radioactivity at 2.5 min and 2.5% of the radioactivity at 60 min. In heart, unchanged tracer represented 18% of radioactivity at 2.5 min and 2.4% at 15 min. The remainder of radioactivity detected in plasma and heart was identified as [N-methyl- 11 C]l-carnitine and [N-methyl- 11 C]acetyl-l-carnitine

  4. Substituent effects on an inverse electron demand hetero Diels-Alder reaction in aqueous solution and organic solvents : Cycloaddition of substituted styrenes to di(2-pyridyl)-1,2,4,5-tetrazine

    NARCIS (Netherlands)

    Wijnen, Jan W.; Zavarise, Silvia; Engberts, Jan B.F.N.; Charton, Marvin

    1996-01-01

    The kinetics of the Diels-Alder reactions of di(2-pyridyl)-1,2,4,5-tetrazine (1) with substituted styrenes 2 was investigated in aqueous media and in organic solvents. The second-order rate constants ofthis reaction increase dramatically in water-rich media. A decrease in pH accelerates the aqueous

  5. Spectrophotometric analysis of vitamin E using Cu(I)-Bathocuproine or/and Fe(II)-2,4,6-tris-(2'-pyridyl)-s-triazine complexes

    International Nuclear Information System (INIS)

    Devi, I.; Memon, S. A.; Khuhawar, M.Y.

    2004-01-01

    Vitamin E (tocopherols and tocotrienols) antioxidants are determined by reducing Cu(II) to Cu(I) or Fe(III) to Fe(II) in presence of vitamin E and subsequent complexation of Cu(I) with bathocuproine and/or Fe(II) with 2,4,6-tris-(2'-pyridyl)-s-triazine (TPTZ). Both the reactions are monitored separately, Cu(I)-bathocuproine at 479 nm where as, Fe(II)-(TPTZ) at 595 nm spectrophotometrically. Linear calibration curves are achieved for both complexes between I to 5mu g ml-1 for vitamin E. The methods were applied for the determination of vitamin E in pharmaceutical preparations and edible oils. Vitamin E, from edible oils, was solvent extracted into n-hexane prior to saponification. Furthermore, a single lined flow was also examined. A larger excess of Cu(II) or Fe =(II) with different concentrations of vitamin E in buffer pH 4 was run on the line and constant amounts of reagent bathocuproine or TPTZ in each case was injected through the injector. The peak height shows a linear relationship for vitamin E between 0.5 to 2.5 mu g ml-1 for both complexes. (author)

  6. Rotational Spectrum and Conformational Analysis of N-methyl-2-aminoethanol: Insights into the Shape of Adrenergic Neurotransmitters

    Science.gov (United States)

    Calabrese, Camilla; Maris, Assimo; Evangelisti, Luca; Piras, Anna; Parravicini, Valentina; Melandri, Sonia

    2018-02-01

    Abstract We describe an experimental and quantum chemical study for the accurate determination of the conformational space of small molecular systems governed by intramolecular non-covalent interactions. The model systems investigated belong to the biological relevant aminoalcohol’s family, and include 2-aminophenylethanol, 2-methylaminophenylethanol, noradrenaline, adrenaline 2-aminoethanol and N-methyl-2-aminoethanol. For the latter molecule, the rotational spectrum in the 6-18 and 59.6-74.4 GHz ranges was recorded in the isolated conditions of a free jet expansion. Based on the analysis of the rotational spectra, two different conformational species and 11 isotopologues were observed and their spectroscopic constants, including 14N-nuclear hyperfine coupling constants and methyl internal rotation barriers, were determined. From the experimental data a structural determination was obtained, which was also used to benchmark accurate quantum chemical calculations on the whole conformational space. Atom in molecules and non-covalent interactions theories allowed the characterization of the position of the intramolecular non-covalent interactions and the energies involved, highlighting the subtle balance responsible of the stabilization of all the molecular systems.

  7. Matrix-isolation FTIR, theoretical structural analysis and reactivity of amino-saccharins: N-(1,1-dioxo-1,2-benzisothiazol-3-yl)- N-methyl amine and - N,N-dimethyl amine

    Science.gov (United States)

    Almeida, R.; Gómez-Zavaglia, A.; Kaczor, A.; Ismael, A.; Cristiano, M. L. S.; Fausto, R.

    2009-12-01

    In this work, two novel amino-substituted derivatives of saccharin, N-(1,1-dioxo-1,2-benzisothiazol-3-yl)- N-methyl amine (MBAD) and N-(1,1-dioxo-1,2-benzisothiazol-3-yl)- N, N-dimethyl amine (DMBAD), were synthesized and characterized, and their molecular structure and vibrational properties were investigated by matrix-isolation FTIR spectroscopy and theoretical calculations undertaken using different levels of approximation. The calculations predicted the existence of two conformers of MBAD. The lowest energy form was predicted to be considerably more stable than the second conformer (Δ E > ca. 20 kJ mol -1) and was the sole form contributing to the infrared spectrum of the compound isolated in solid xenon. Both conformers have planar amine moieties. In the case of DMBAD, only one doubly-degenerated-by-symmetry conformer exists, with the amine nitrogen atom considerably pyramidalized. The effect of the electron-withdrawing saccharyl ring on the C-N bond lengths is discussed. The different structural preferences around the amine nitrogen atom in the two molecules were explained in terms of repulsive interactions involving the additional methyl group of DMBAD. Observed structural features are correlated with the reactivity exhibited by the two compounds towards nucleophiles. The experimentally obtained spectra of the matrix-isolated monomers of MBAD and DMBAD were fully assigned by comparison with the corresponding calculated spectra.

  8. Direct determination of N-methyl-2-pyrrolidone metabolites in urine by HPLC-electrospray ionization-MS/MS using deuterium-labeled compounds as internal standard.

    Science.gov (United States)

    Suzuki, Yoshihiro; Endo, Yoko; Ogawa, Masanori; Yamamoto, Shinobu; Takeuchi, Akito; Nakagawa, Tomoo; Onda, Nobuhiko

    2009-11-01

    N-methyl-2-pyrrolidone (NMP) has been used in many industries and biological monitoring of NMP exposure is preferred to atmospheric monitoring in occupational health. We developed an analytical method that did not include solid phase extraction (SPE) but utilized deuterium-labeled compounds as internal standard for high-performance liquid chromatography-electrospray ionization-mass spectrometry using a C30 column. Urinary concentrations of NMP and its known metabolites 5-hydoxy-N-methyl-2-pyrrolidone (5-HNMP), N-methyl-succinimide (MSI), and 2-hydroxy-N-methylsuccinimide (2-HMSI) were determined in a single run. The method provided baseline separation of these compounds. Their limits of detection in 10-fold diluted urine were 0.0001, 0.006, 0.008, and 0.03 mg/L, respectively. Linear calibration covered a biological exposure index (BEI) for urinary concentration. The within-run and total precisions (CV, %) were 5.6% and 9.2% for NMP, 3.4% and 4.2% for 5-HNMP, 3.7% and 6.0% for MSI, and 6.5% and 6.9% for 2-HMSI. The method was evaluated using international external quality assessment samples, and urine samples from workers exposed to NMP in an occupational area.

  9. Oral Methylated N-Aryl Chitosan Derivatives for Inducing Immune ...

    African Journals Online (AJOL)

    TM-CM-CS) and methylated N-(4-pyridinylmethyl) chitosan (TM-Py-CS), with Eqiva degree (equivalent degree) were studied by in vitro absorption enhancement on the transepithelial electrical resistance (TEER) in Caco-2 cell monolayers as ...

  10. Calorimetric determination of enthalpies for the proton ionization of N,N-bis[2-hydroxyethyl]-2-aminoethanesulfonic acid (BES) and N-tris[hydroxymethyl]methyl-2-aminoethanesulfonic acid (TES) in water-methanol mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Bulos, B.N.; Jumean, F.H

    2004-02-19

    The enthalpies of proton ionization of the biochemical buffers N,N-bis[2-hydroxyethyl]-2-aminoethanesulfonic acid (BES) and N-tris[hydroxymethyl]methyl-2-aminoethanesulfonic acid (TES) were obtained in water-methanol mixtures in which the methanol mole fraction (X{sub m}) varied in the range 0-0.36. For both buffers, ionization enthalpy for the first proton ({delta}H{sub 1}) was small in all solvent media. However, upon addition of methanol, {delta}H{sub 2} increased steadily from 22.2 to a maximum of 27.2 kJ mol{sup -1} for BES, whereas for TES it varied from 30.0 to 32.4, with a minimum of 28.6 kJ mol{sup -1} at X{sub m}=0.123. It is noteworthy that this solvent composition lies within the region of maximum structure enhancement of water by methanol. The results were interpreted in terms of methanol-water interactions.

  11. Dermal absorption and urinary elimination of N-methyl-2-pyrrolidone.

    Science.gov (United States)

    Bader, Michael; Keener, Stephen A; Wrbitzky, Renate

    2005-09-01

    The dermal absorption of the solvent N-methyl-2-pyrrolidone (NMP) and its elimination in urine was investigated in an experimental study. Seven volunteers were exposed to 1045 mg of liquid NMP under occlusive conditions for 2 h. Urine was collected before, during and up to 72 h after the exposure and analysed for NMP by GC/MS after liquid-liquid extraction. Additionally, the remaining NMP in the pads was determined to estimate the total dermal uptake. The concentration of NMP in urine increased rapidly after beginning of the exposure up to 1 h after the exposure was completed. A peak concentration of 1,836+/-863 microg/l was observed, the half-life in urine was 3.2 h. About 0.5% of the absorbed dose was excreted metabolically unchanged. An average dermal absorption of 5.5 mg cm(-2) h(-1) was calculated. The results of this study show that the percutaneous absorption of NMP may contribute significantly to the overall uptake of the solvent, e.g. in the workplace. Therefore, a biological monitoring of NMP exposed workers is essential for occupational-medical surveillance.

  12. Post-synthetic modification of porphyrin-encapsulating metal-organic materials by cooperative addition of inorganic salts to enhance CO 2/CH 4 selectivity

    KAUST Repository

    Zhang, ZhenJie

    2012-08-21

    Keeping MOM: Reaction of biphenyl-3,4\\',5-tricarboxylate and Cd(NO 3) 2 in the presence of meso-tetra(N-methyl-4-pyridyl) porphine tetratosylate afforded porph@MOM-11, a microporous metal-organic material (MOM) that encapsulates cationic porphyrins and solvent in alternating open channels. Porph@MOM-11 has cation and anion binding sites that facilitate cooperative addition of inorganic salts (such as M +Cl -) in a stoichiometric fashion. © 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Post-synthetic modification of porphyrin-encapsulating metal-organic materials by cooperative addition of inorganic salts to enhance CO 2/CH 4 selectivity

    KAUST Repository

    Zhang, ZhenJie; Gao, Wenyang; Wojtas, Łukasz; Ma, Shengqian; Eddaoudi, Mohamed; Zaworotko, Michael J.

    2012-01-01

    Keeping MOM: Reaction of biphenyl-3,4',5-tricarboxylate and Cd(NO 3) 2 in the presence of meso-tetra(N-methyl-4-pyridyl) porphine tetratosylate afforded porph@MOM-11, a microporous metal-organic material (MOM) that encapsulates cationic porphyrins and solvent in alternating open channels. Porph@MOM-11 has cation and anion binding sites that facilitate cooperative addition of inorganic salts (such as M +Cl -) in a stoichiometric fashion. © 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Synthesis, NMR spectral and antimicrobial studies of some [N-methyl-3t-alkyl-2r,6c-diarylpiperidin-4-ylidine]-5‧-methylthiazolidine-4-ones

    Science.gov (United States)

    Prakash, S. M.; Pandiarajan, K.; Kumar, S.

    2013-06-01

    Four new [N-methyl-3t-alkyl-2r,6c-diaryl-4-ylidine]-5'-methylthiozolidin-4-ones 9-12 have been synthesized by the condensation of N-methyl-3t-alkyl-2r,6c-diarylpiperidin-4-one thiosemicarbazones with ethyl 2-bromopropionate. These compounds have been characterized using FT-IR, 1H NMR, 13C NMR spectral techniques. HOMOCOSY, HSQC and HMBC spectral study have been done for [N-methyl-3,3-dimethyl-2r,6c-bis(p-methoxyphenyl)piperidin-4-ylidine]-5'-methylthiazolidine-4-one (12). Two geometrical isomers are formed in this reaction. In all these compounds piperidin rings adopt chair conformation. The rotation of the aryl group at C-2 is rather slow in 10-12. Antimicrobial activities have also been studied for 9-12. These compounds are active against all the tested bacterial and fungal strains.

  15. Crystal structure of {2,2′-[N,N′-bis(pyridin-2-ylmethylcyclohexane-trans-1,2-diyldi(nitrilo]diacetato}cobalt(III hexafluoridophosphate

    Directory of Open Access Journals (Sweden)

    Craig C. McLauchlan

    2015-04-01

    Full Text Available The title compound [Co(C22H26N4O4]PF6, commonly known as [Co(bpcd]PF6, where bpcd2− is derived from the historical ligand name N,N′-bis(2-pyridylmethyl-trans-1,2-diaminocyclohexane-N,N′-diacetate, crystallized by slow evaporation of a saturated acetonitrile solution in air. The cation of the hexafluoridophosphate salt has the CoIII atom in a distorted octahedral coordination geometry provided by an N4O2 donor atom set. The acetate groups, which are oriented trans with respect to each other, exhibit monodentate coordination whereas the pyridyl N atoms are coordinating in a cis configuration. The geometry of the cation is compared to the geometries of other diamino diacetate complexes with CoIII.

  16. Extraction of pentylbenzene from high molar mass alkanes (C14 and C17) by N-methyl-2-pyrrolidone

    International Nuclear Information System (INIS)

    Fandary, Mohamed S.; Al-Jimaz, Adel S.; Al-Kandary, Jasem A.; Fahim, Mohamed A.

    2006-01-01

    Equilibrium tie line data have been determined for the two ternary liquid systems: {tetradecane, or heptadecane + pentylbenzene + N-methyl-2-pyrrolidone (NMP)} over a temperature range of (298 to 328) K. The two systems studied exhibit type I liquid + liquid phase diagram. The effect of temperature and n-alkane chain length upon solubility, selectivity, and distribution coefficients were investigated experimentally

  17. Measuring urinary N-acetyl-S-(4-hydroxy-2-methyl-2-buten-1-yl)-L-cysteine (IPMA3) as a potential biomarker of isoprene exposure.

    Science.gov (United States)

    Alwis, K Udeni; Bailey, T Liz; Patel, Dhrusti; Wang, Liqun; Blount, Benjamin C

    2016-10-19

    Isoprene, the 2-methyl analog of 1,3-butadiene, is identified as a possible human carcinogen by the International Agency for Research on Cancer (IARC). Isoprene is ubiquitous in the environment with numerous natural and anthropogenic sources. Tobacco smoke is the main exogenous source of isoprene exposure in indoor environments. Among smoke constituents, isoprene is thought to contribute significantly to cancer risk; however, no selective urinary biomarkers of isoprene exposure have been identified for humans. In this manuscript, we measured the minor isoprene metabolite IPMA1 (mixture of N-acetyl-S-(1-[hydroxymethyl]-2-methyl-2-propen-1-yl)-L-cysteine and N-acetyl-S-(2-hydroxy-3-methyl-3-buten-1-yl)-L-cysteine), and we identified IPMA3 (N-acetyl-S-(4-hydroxy-2-methyl-2-buten-1-yl)-L-cysteine) as a major isoprene metabolite and novel isoprene exposure biomarker for humans. Urinary isoprene metabolites were measured using ultra high performance liquid chromatography coupled with electrospray ionization triple quad tandem mass spectrometry (UPLC/ESI-MSMS). The detection rates of IPMA1 and IPMA3 are <20% and 82%, respectively. The selectivity and abundance of IPMA3 make it a useful urinary biomarker of isoprene exposure. The limit of detection of IPMA3 in urine was 0.5 ng mL -1 . IPMA3 was stable under different storage temperatures and following ten freeze-thaw cycles. The average recovery of urine spiked with IPMA3 at three different levels was 99%. IPMA3 was measured in urine samples received from 75 anonymous subjects; the median (25th percentile, 75th percentile) IPMA3 level in smokers was 36.2 (18.2, 56.8) ng mL -1 and non-smokers 2.31 (2.31, 4.38) ng mL -1 . Application of this method to large population studies will help to characterize isoprene exposure and assess potential health impact. Published by Elsevier B.V.

  18. 2′-O Methylation of Internal Adenosine by Flavivirus NS5 Methyltransferase

    Science.gov (United States)

    Dong, Hongping; Chang, David C.; Hua, Maggie Ho Chia; Lim, Siew Pheng; Chionh, Yok Hian; Hia, Fabian; Lee, Yie Hou; Kukkaro, Petra; Lok, Shee-Mei; Dedon, Peter C.; Shi, Pei-Yong

    2012-01-01

    RNA modification plays an important role in modulating host-pathogen interaction. Flavivirus NS5 protein encodes N-7 and 2′-O methyltransferase activities that are required for the formation of 5′ type I cap (m7GpppAm) of viral RNA genome. Here we reported, for the first time, that flavivirus NS5 has a novel internal RNA methylation activity. Recombinant NS5 proteins of West Nile virus and Dengue virus (serotype 4; DENV-4) specifically methylates polyA, but not polyG, polyC, or polyU, indicating that the methylation occurs at adenosine residue. RNAs with internal adenosines substituted with 2′-O-methyladenosines are not active substrates for internal methylation, whereas RNAs with adenosines substituted with N6-methyladenosines can be efficiently methylated, suggesting that the internal methylation occurs at the 2′-OH position of adenosine. Mass spectroscopic analysis further demonstrated that the internal methylation product is 2′-O-methyladenosine. Importantly, genomic RNA purified from DENV virion contains 2′-O-methyladenosine. The 2′-O methylation of internal adenosine does not require specific RNA sequence since recombinant methyltransferase of DENV-4 can efficiently methylate RNAs spanning different regions of viral genome, host ribosomal RNAs, and polyA. Structure-based mutagenesis results indicate that K61-D146-K181-E217 tetrad of DENV-4 methyltransferase forms the active site of internal methylation activity; in addition, distinct residues within the methyl donor (S-adenosyl-L-methionine) pocket, GTP pocket, and RNA-binding site are critical for the internal methylation activity. Functional analysis using flavivirus replicon and genome-length RNAs showed that internal methylation attenuated viral RNA translation and replication. Polymerase assay revealed that internal 2′-O-methyladenosine reduces the efficiency of RNA elongation. Collectively, our results demonstrate that flavivirus NS5 performs 2′-O methylation of internal adenosine of

  19. N-(2-Chlorophenyl-2-methylbenzamide

    Directory of Open Access Journals (Sweden)

    B. Thimme Gowda

    2008-08-01

    Full Text Available In the structure of the title compound (N2CP2MBA, C14H12ClNO, the conformations of the N—H and C=O bonds are trans to each other. Furthermore, the conformation of the N—H bond is syn to the ortho-chloro group in the aniline ring and the C=O bond is syn to the ortho-methyl substituent in the benzoyl ring, similar to what is observed in 2-chloro-N-(2-chlorophenylbenzamide and 2-methyl-N-phenylbenzamide. The amide group makes almost the same dihedral angles of 41.2 (14 and 42.2 (13° with the aniline and benzoyl rings, respectively, while the dihedral angle between the benzoyl and aniline rings is only 7.4 (3°. The molecules in N2CP2MBA are packed into chains through N—H...O hydrogen bonds.

  20. (Acetonitrile-κNchloridobis[2-(pyridin-2-ylphenyl-κ2C1,N]iridium(III

    Directory of Open Access Journals (Sweden)

    Florian Blasberg

    2011-12-01

    Full Text Available The IrIII atom of the title compound, [Ir(C11H8N2Cl(CH3CN], displays a distorted octahedral coordination. The pyridyl groups are in trans positions [N—Ir—N = 173.07 (10°], while the phenyl groups are trans with respect to the acetonitrile and chloride groups [C—Ir—N = 178.13 (11 and C—Ir—Cl = 176.22 (9°]. The pyridylphenyl groups only show a small deviation from planarity, with the dihedral angle between the planes of the two six-membered rings in each pyridylphenyl group being 5.6 (2 and 5.8 (1°. The crystal packing shows intermolecular C—H...Cl, C—H...π(acetonitrile and C—H...π(pyridylphenyl contacts.

  1. (R,S)-2-chlorophenoxyl pyrazolides as novel substrates for improving lipase-catalyzed hydrolytic resolution.

    Science.gov (United States)

    Kao, Min-fang; Lu, Pei-yu; Kao, Jou-yan; Wang, Pei-yun; Wu, An-chi; Tsai, Shau-Wei

    2012-01-01

    The best reaction condition of Candida antartica lipase B as biocatalyst, 3-(2-pyridyl)pyrazole as leaving azole, and water-saturated methyl t-butyl ether as reaction medium at 45°C were first selected for performing the hydrolytic resolution of (R,S)-2-(4-chlorophenoxyl) azolides (1-4). In comparison with the kinetic resolution of (R,S)-2-phenylpropionyl 3-(2-pyridyl)pyrazolide or (R,S)-α-methoxyphenylacetyl 3-(2-pyridyl)pyrazolide at the same reaction condition, excellent enantioselectivity with more than two order-of-magnitudes higher activity for each enantiomer was obtained. The resolution was then extended to other (R,S)-3-(2-pyridyl)pyrazolides (5-7) containing 2-chloro, 3-chloro, or 2,4-dichloro substituent, giving good (E > 48) to excellent (E > 100) enantioselectivity. The thermodynamic analysis for 1, 2, and 4-7 demonstrates profound effects of the acyl or leaving moiety on varying enthalpic and entropic contributions to the difference of Gibbs free energies. A thorough kinetic analysis further indicates that on the basis of 6, the excellent enantiomeric ratio for 4 and 7 is due to the higher reactivity of (S)-4 and lower reactivity of (R)-7, respectively. Copyright © 2011 Wiley-Liss, Inc.

  2. Low temperature and high pressure crystals of room temperature ionic liquid: N, N-diethyl-N-methyl-N-(2-methoxyethyl) ammonium tetrafluoroborate

    International Nuclear Information System (INIS)

    Abe, Hiroshi; Imai, Yusuke; Takekiyo, Takahiro; Yoshimura, Yukihiro; Hamaya, Nozomu

    2014-01-01

    Crystals of room temperature ionic liquid (RTIL) are obtained separately at low temperature or under high pressure. The RTIL is N, N-diethyl-N-methyl-N-(2-methoxyethyl) ammonium tetrafluoroborate, [DEME][BF 4 ]. At ambient pressure, low-temperature (LT) crystals appeared on slow cooling. By simultaneous X-ray diffraction and differential scanning calorimetry (DSC) measurements, metastable monoclinic and stable orthorhombic phases coexist in pure [DEME][BF 4 ]. Furthermore, the DSC thermal trace indicates that the metastable monoclinic phase was stabilized by adding water. In contrast, on compression process up to 7.6 GPa, crystallization is completely suppressed even upon slow compression. Direct observations using optical microscopy also support no crystal domain growth on compression process. High-pressure (HP) crystals at room temperature were seen only on decompression process, where two different kinds of crystals appeared subsequently. By crystal structure analysis, the LT crystal structures have no relation with the HP ones. Moreover, both metastable monoclinic phase at low temperature and higher pressure crystal has a folding molecular conformation and anti-parallel pairing of the [DEME] cation as the instability factors

  3. Crystal Structure of N,N-bis-(3-Carbomethoxy-5-methyl-pyrazol-1-ylmethylaniline

    Directory of Open Access Journals (Sweden)

    Taibi Ben-Hadda

    2002-09-01

    Full Text Available The tripodal ligand N,N-bis-(3-carbomethoxy-5-methylpyrazol-1-ylmethyl aniline (2 has been prepared by the condensation of aniline with two equivalents of N-hydroxymethyl[3-carbomethoxy-5-methyl]pyrazole. The molecule consists of two structurally analogous 3-carbomethoxy-5-methylpyrazol-1-ylmethyl moieties, which adopt a transoidal conformation via a central aniline ring, suggesting that this tripodal ligand is highly flexible and could accommodate many metals by coordination.

  4. Rotational Spectrum and Conformational Analysis of N-Methyl-2-Aminoethanol: Insights into the Shape of Adrenergic Neurotransmitters

    Directory of Open Access Journals (Sweden)

    Camilla Calabrese

    2018-02-01

    Full Text Available We describe an experimental and quantum chemical study for the accurate determination of the conformational space of small molecular systems governed by intramolecular non-covalent interactions. The model systems investigated belong to the biological relevant aminoalcohol's family, and include 2-amino-1-phenylethanol, 2-methylamino-1-phenylethanol, noradrenaline, adrenaline 2-aminoethanol, and N-methyl-2-aminoethanol. For the latter molecule, the rotational spectrum in the 6–18 and 59.6–74.4 GHz ranges was recorded in the isolated conditions of a free jet expansion. Based on the analysis of the rotational spectra, two different conformational species and 11 isotopologues were observed and their spectroscopic constants, including 14N-nuclear hyperfine coupling constants and methyl internal rotation barriers, were determined. From the experimental data a structural determination was performed, which was also used to benchmark accurate quantum chemical calculations on the whole conformational space. Atom in molecules and non-covalent interactions theories allowed the characterization of the position of the intramolecular non-covalent interactions and the energies involved, highlighting the subtle balance responsible of the stabilization of all the molecular systems.

  5. Aquachloridobis[5-(2-pyridyl-1H-tetrazolato-κN1]iron(III

    Directory of Open Access Journals (Sweden)

    Bo Wang

    2009-08-01

    Full Text Available The title compound, [Fe(C6H4N52Cl(H2O], was synthesized by hydrothermal reaction of FeCl3 with 2-(1H-tetrazol-5-ylpyridine. The iron(III metal centre exhibits a distorted octahedral coordination geometry provided by four N atoms from two bidentate organic ligands, one water O atom and one chloride anion. The pyridine and tetrazole rings are nearly coplanar [dihedral angles = 4.32 (15 and 5.04 (14°]. In the crystal structure, intermolecular O—H...N hydrogen bonds link the complex molecules into a two-dimensional network parallel to (100.

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

    Science.gov (United States)

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

    2017-07-01

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

  7. Solvent-Induced Change of Electronic Spectra and Magnetic Susceptibility of Co(II) Coordination Polymer with 2,4,6-Tris(4-pyridyl)-1,3,5-triazine.

    Science.gov (United States)

    Polunin, Ruslan A; Burkovskaya, Nataliya P; Satska, Juliya A; Kolotilov, Sergey V; Kiskin, Mikhail A; Aleksandrov, Grigory G; Cador, Olivier; Ouahab, Lahcène; Eremenko, Igor L; Pavlishchuk, Vitaly V

    2015-06-01

    One-dimensional coordination polymer [Co(Piv)2(4-ptz)(C2H5OH)2]n (compound 1, Piv(-) = pivalate, 4-ptz = 2,4,6-tris(4-pyridyl)-1,3,5-triazine) was synthesized by interaction of Co(II) pivalate with 4-ptz. Desolvation of 1 led to formation of [Co(Piv)2(4-ptz)]n (compound 2), which adsorbed N2 and H2 at 78 K as a typical microporous sorbent. In contrast, absorption of methanol and ethanol by 2 at 295 K led to structural transformation probably connected with coordination of these alcohols to Co(II). Formation of 2 from 1 was accompanied by change of color of sample from orange to brown and more than 2-fold decrease of molar magnetic susceptibility (χM) in the temperature range from 2 to 300 K. Resolvation of 2 by ethanol or water resulted in restoration of spectral characteristics and χM values almost to the level of that of 1. χMT versus T curves for 1 and samples, obtained by resolvation of 2 by H2O or C2H5OH, were fitted using a model for Co(II) complex with zero-field splitting of this ion.

  8. Effect of DNA sequence, ionic strength, and cationic DNA affinity binders on the methylation of DNA by N-methyl-N-nitrosourea

    International Nuclear Information System (INIS)

    Wurdeman, R.L.; Gold, B.

    1988-01-01

    DNA alkylation by N-alkyl-N-nitrosoureas is generally accepted to be responsible for their mutagenic, carcinogenic, and antineoplastic activities. The exact nature of the ultimate alkylating intermediate is still controversial, with a variety of species having been nominated. The sequence specificity for DNA alkylation by simple N-alkyl-N-nitrosoureas has not been reported, although such information is basic in understanding the specific point mutations induced by these compounds in oncogene targets. These two points are addressed by using N-methyl-N-nitrosourea methylation of a 576 base-pair 32 P-end-labeled DNA restriction fragment and high-resolution polyacrylamide sequencing gels. This method provides information on the formation of N 7 -methylguanine, by the generation of single-strand breaks upon exposure to piperidine

  9. Synthesis, crystal structure, and spectroscopic characterization of trans-bis[(mu-1,3-bis(4-pyridyl)propane)(mu-(3-thiopheneacetate-O))(3-thiopheneacetate-O)]dicopper(II), [[Cu2(O2CCH2C4H3S)4mu-(BPP)2

    Science.gov (United States)

    Marinho, Maria Vanda; Yoshida, Maria Irene; Guedes, Kassilio J; Krambrock, Klaus; Bortoluzzi, Adailton J; Hörner, Manfredo; Machado, Flávia C; Teles, Wagner M

    2004-02-23

    From the reaction between a dinuclear paddle-wheel carboxylate, namely [Cu2mu-(O2CCH2C4H3S)4] (1), and the flexible ligand 1,3-bis(4-pyridyl)propane (BPP) a neutral 2-D coordination polymer [[Cu2(O2CCH2C4H3S)4mu-(BPP)2

  10. Synthesis, Characterization and Gold Loading of Polystyrene-Poly(pyridyl methacrylate) Core-Shell Latex Systems

    NARCIS (Netherlands)

    Oláh, A.; Hempenius, Mark A.; Vancso, Gyula J.

    2004-01-01

    In this research, novel 3-(2-pyridyl)propyl methacrylate and 3-(3-pyridyloxy)propyl methacrylate monomers were synthesized and emulsion polymerized on colloidal polystyrene seeds, resulting in core–shell latex systems. The cores and the core–shell particles were characterized by static light

  11. 6-Methyl-1,2,4-benzenetriol, a new intermediate in penicillic acid biosynthesis in Penicillium cyclopium

    International Nuclear Information System (INIS)

    Sekiguchi, J.; Katayama, S.; Yamada, Y.

    1987-01-01

    Penicillic acid-negative mutants were obtained from a color mutant derived from Penicillium cyclopium NRRL 1888 through N-methyl-N'-nitro-N-nitrosoguanidine treatment. One mutant (SK2N6) accumulated 6-methyl-1,2,4-benzenetriol, which was not previously known to be a metabolite of P. cyclopium, in addition to orsellinic acid and orcinol. The radioactivity of [1- 14 C]acetic acid was rapidly incorporated into 6-methyl-1,2,4-benzenetriol in a culture of P. cyclopium SK2N6. Moreover, the radioactivity of [ 14 C]6-methyl-1,2,4-benzenetriol was efficiently incorporated into penicillic acid in a culture of P. cyclopium NRRL 1888. These data indicate that 6-methyl-1,2,4-benzenetriol is a precursor for penicillic acid biosynthesis. The results on the addition of 1,4-dihydroxy-6-methoxy-2-methylbenzene, 6-methoxy-2-methylbenzoquinone (1,4), and 1-O-methylorcinol to a culture of P. cyclopium SK2N6 indicated that only the former two compounds are converted to penicillic acid. Thus, a new portion of the penicillic acid biosynthetic pathway is proposed

  12. Extraction and spectrophotometric determination of vanadium(V) with N-hydroxy-N-m-tolyl-N'-(2-methyl-5-chloro)-phenyl-p-toluamidine hydrochloride in presence of salicylic, anthranilic and phthalic acids

    Energy Technology Data Exchange (ETDEWEB)

    Patel, K S; Deb, K K; Mishra, R [Ravishankar Univ., Raipur (India). Dept. of Chemistry

    1981-02-01

    The present work deals with the solvent extraction and simultaneous spectrophotometric determination of microgram quantities of vanadium(V) as mixed ligand complex with N-hydroxy-N-m-tolyl-N'-(2-methyl-5-chloro)-phenyl-p-toluamidine hydrochloride (HTMCPTH) and six carboxylic acids viz. salicylic, acetylsalicylic (aspirin), sulfosalicylic, anthranilic, N-phenyl-anthranilic and phthalic. The method presented here is simple, rapid, sensitive and reasonably selective.

  13. Extraction and spectrophotometric determination of vanadium(V) with N-hydroxy-N-m-tolyl-N'-(2-methyl-5-chloro)-phenyl-p-toluamidine hydrochloride in presence of salicylic, anthranilic and phthalic acids

    International Nuclear Information System (INIS)

    Patel, K.S.; Deb, K.K.; Mishra, R.

    1981-01-01

    The present work deals with the solvent extraction and simultaneous spectrophotometric determination of microgram quantities of vanadium(V) as mixed ligand complex with N-hydroxy-N-m-tolyl-N'-(2-methyl-5-chloro)-phenyl-p-toluamidine hydrochloride (HTMCPTH) and six carboxylic acids viz. salicylic, acetylsalicylic (aspirin), sulfosalicylic, anthranilic, N-phenyl-anthranilic and phthalic. The method presented here is simple, rapid, sensitive and reasonably selective. (author)

  14. Quantification of 5-methyl-2'-deoxycytidine in the DNA.

    Science.gov (United States)

    Giel-Pietraszuk, Małgorzata; Insińska-Rak, Małgorzata; Golczak, Anna; Sikorski, Marek; Barciszewska, Mirosława; Barciszewski, Jan

    2015-01-01

    Methylation at position 5 of cytosine (Cyt) at the CpG sequences leading to formation of 5-methyl-cytosine (m(5)Cyt) is an important element of epigenetic regulation of gene expression. Modification of the normal methylation pattern, unique to each organism, leads to the development of pathological processes and diseases, including cancer. Therefore, quantification of the DNA methylation and analysis of changes in the methylation pattern is very important from a practical point of view and can be used for diagnostic purposes, as well as monitoring of the treatment progress. In this paper we present a new method for quantification of 5-methyl-2'deoxycytidine (m(5)C) in the DNA. The technique is based on conversion of m(5)C into fluorescent 3,N(4)-etheno-5-methyl-2'deoxycytidine (εm(5)C) and its identification by reversed-phase high-performance liquid chromatography (RP-HPLC). The assay was used to evaluate m(5)C concentration in DNA of calf thymus and peripheral blood of cows bred under different conditions. This approach can be applied for measuring of 5-methylcytosine in cellular DNA from different cells and tissues.

  15. Bis(O-n-butyl dithio­carbonato-κ2 S,S′)bis­(pyridine-κN)manganese(II)

    Science.gov (United States)

    Alam, Naveed; Ehsan, Muhammad Ali; Zeller, Matthias; Mazhar, Muhammad; Arifin, Zainudin

    2011-01-01

    The structure of the title manganese complex, [Mn(C5H9OS2)2(C5H5N)2] or [Mn(S2CO-n-Bu)2(C5H5N)2], consists of discrete monomeric entities with Mn2+ ions located on centres of inversion. The metal atom is coordinated by a six-coordinate trans-N2S4 donor set with the pyridyl N atoms located in the apical positions. The observed slight deviations from octa­hedral geometry are caused by the bite angle of the bidentate κ2-S2CO-n-Bu ligands [69.48 (1)°]. The O(CH2)3(CH3) chains of the O-n-butyl dithio­carbonate units are disordered over two sets of sites with an occupancy ratio of 0.589 (2):0.411 (2). PMID:22090847

  16. Facile syntheses of isotope-labeled chiral octahydroindole-2-carboxylic acid and its N-methyl analog

    International Nuclear Information System (INIS)

    Yinsheng Zhang

    2012-01-01

    We have synthesized deuterium and carbon-14 labeled enantiomerically pure octahydroindole-2-carboxylic acid (PD0140417), N-methyl octahydroindole-2-carboxylic acid (PD0348183) and their racemic analogs (PD0108405 and PD0338055). [ring-U- 14 C]PD0140417 was prepared from [ring-U- 14 C]benzoic acid in a seven-step synthesis in 6.2% overall radiochemical yield. [ 14 C]PD0348183 was prepared from [ 14 C]BaCO 3 in a five-step synthesis in 16% radiochemical yield. Additionally, [D]PD0108405 and [D]PD0338055 were synthesized by direct platinum-catalyzed hydrogenation with deuterium gas. (author)

  17. Synthesis, spectral and thermal studies of pyridyl adducts of Zn(II) and Cd(II) dithiocarbamates, and their use as single source precursors for ZnS and CdS nanoparticles

    OpenAIRE

    Onwudiwe, Damian C.; Strydom, Christien A.; Jordaan, Anine; Oluwafemi, Oluwatobi S.; Hosten, Eric

    2014-01-01

    The synthesis, spectroscopic characterisation, and thermal studies of pyridyl adducts of Zn(II) and Cd(II) complexes of N-ethyl-N-phenyl dithiocarbamate, represented as [ZnL2py] and [CdL2py2], are reported. Single-crystal X-ray structural analysis of the Zn compound showed that it is five-coordinate with four sulphurs from dithiocarbamate and one nitrogen from pyridine in a distorted square pyramidal geometry. The thermogravimetric studies indicate that the zinc and cadmium compou...

  18. Density, refraction index and vapor–liquid equilibria of N-methyl-2-hydroxyethylammonium butyrate plus (methyl acetate or ethyl acetate or propyl acetate) at several temperatures

    International Nuclear Information System (INIS)

    Alvarez, V.H.; Mattedi, S.; Aznar, M.

    2013-01-01

    Highlights: ► Densities, refraction indices and VLE were measured for ester + m-2-HEAB mixtures. ► V E , apparent molar volumes and thermal expansion coefficients were calculated. ► Peng–Robinson EoS + Wong–Sandler mixing rule + COSMO-SAC predicted the data. -- Abstract: This paper reports the densities, refraction indices, and vapor liquid equilibria for binary systems ester + N-methyl-2-hydroxyethylammonium butyrate (m-2-HEAB): methyl acetate (1) + m-2-HEAB (2), ethyl acetate (1) + m-2-HEAB and propyl acetate (1) + m-2-HEAB (2). The excess molar volumes, deviations in the refraction index, apparent molar volumes, and thermal expansion coefficients for the binary systems were fitted to polynomial equations. The Peng–Robinson equation of state, coupled with the Wong–Sandler mixing rule, is used to describe the experimental data. Since the predictive activity coefficient model COSMO-SAC is used in the Wong–Sandler mixing rule, the resulting thermodynamic model is a completely predictive one. The prediction results for the density and for the vapor–liquid equilibria have a deviation lower than 1.0% and 1.1%, respectively

  19. Theoretical study of the regioselectivity of the interaction of 3-methyl-4-pyrimidone and 1-methyl-2-pyrimidone with Lewis acids.

    Science.gov (United States)

    Kasende, Okuma Emile; Muya, Jules Tshishimbi; Broeckaert, Lies; Maes, Guido; Geerlings, Paul

    2012-08-23

    A density functional theory (DFT) study is performed to determine the stability of the complexes formed between either the N or O site of 3-methyl-4-pyrimidone and 1-methyl-2-pyrimidone molecules and different ligands. The studied ligands are boron and alkali Lewis acids, namely, B(CH(3))(3), HB(CH(3))(2), H(2)B(CH(3)), BH(3), H(2)BF, HBF(2), BF(3), Li(+), Na(+), and K(+). The acids are divided into two groups according to their hardness. The reactivity predictions, according to the molecular electrostatic potential (MEP) map and the natural bond orbital (NBO) analysis, are in agreement with the calculated relative stabilities. Our findings reveal a strong regioselectivity with borane and its derivatives preferring the nitrogen site in both pyrimidone isomers, while a preference for oxygen is observed for the alkali acids in the 3-methyl-4-pyrimidone molecule. The complexation of 1-methyl-2-pyrimidone with these hard alkali acids does not show any discrimination between the two sites due to the presence of a continuous delocalized density region between the nitrogen and the oxygen atoms. The preference of boron Lewis acids toward the N site is due to the stronger B-N bond as compared to the B-O bond. The influence of fluorine or methyl substitution on the boron atom is discussed through natural orbital analysis (NBO) concentrating on the overlap of the boron empty p-orbital with the F lone pairs and methyl hyperconjugation, respectively. The electrophilicity of the boron acids gives a good overall picture of the interaction capabilities with the Lewis base.

  20. Technetium-99m labeling of N-[N-(3-diphenylphosphino propionyl)glycyl]cysteine (PN2S-OH) and its methyl ester derivative (PN2S-OMe)

    International Nuclear Information System (INIS)

    Visentin, Roberta; Giron, Maria Cecilia; Bello, Michele; Mazzi, Ulderico

    2004-01-01

    N-[N-(3-diphenylphosphinopropionyl)glycyl]cysteine and its methyl ester derivative were labeled with 99m Tc at neutral pH, leading to a single species in high yield (>95%) in 30 min. RP-HPLC comparison with the analogue Re V -oxo complexes identified the labeled compounds as the anti isomers of pentacoordinated 99m TcO[PN 2 S]-OH and 99m TcO[PN 2 S]-OMe complexes. The compounds are stable from pH 7 to pH 9 when 99m TcO[PN 2 S]-OH interconverts to related syn isomer, while 99m TcO[PN 2 S]-OMe undergoes both saponification and interconversion. They exhibit high stability in human plasma and in vivo (mice), and a biodistribution characterized by hepatobiliary excretion

  1. Study of the role of β-adrenoceptors in the mechanisms of hemodynamic action and radioprotective activity of 2-methyl-5-vinylpyridine copolymer with 2-methyl-5-vinylpyridinium-N-oxide

    International Nuclear Information System (INIS)

    Korovkina, Eh.P.; Mikhajlov, P.P.; Tsorin, I.B.

    2000-01-01

    The effect of the new water soluble copolymer 2-methyl-5-vinylpyridine with 2-methyl-5-vinylpyridinium-N-oxide on the arterial pressure in dogs and cats is studied; the possibility of modifying the polymer hemodynamical activity under the impact of the β-propranolol blocking is investigated; the effect of the latter one on the copolymer in dogs is evaluated. The therapeutic antiradiation efficiency of the copolymer was judged by the irradiated dogs survival during 45 days. The dogs were subjected to the 137 Cs γ-radiation impact with the dose rate of 153 cGy in the 330 cGy. It is shown that the copolymer causes depression reaction in the anesthetized dogs and cats characteristic for the β-adrenomimetics This effect is leveled by the nonselective β-adrenoblocking - propranolol. The preliminary introduction of propranolol in dogs decreased the therapeutic antiradiation-efficiency of the given copolymer from 68.4 up to 8.3 % [ru

  2. Experimental and computational approaches of a novel methyl (2E)-2-{[N-(2-formylphenyl)(4-methylbenzene)sulfonamido]methyl}-3-(4-chlorophenyl)prop-2-enoate: A potential antimicrobial agent and an inhibition of penicillin-binding protein

    Science.gov (United States)

    Murugavel, S.; Vetri velan, V.; Kannan, Damodharan; Bakthadoss, Manickam

    2016-07-01

    The title compound methyl(2E)-2-{[N-(2-formylphenyl) (4-methylbenzene)sulfonamido]methyl}-3-(4-chlorophenyl) prop-2-enoate (MFMSC) has been synthesized and single crystals were grown by slow evaporation solution growth technique at room temperature. Structural and vibrational spectroscopic studies were carried out by using single crystal X-ray diffraction, FT-IR and NMR spectral analysis together with DFT method using GAUSSIAN'03 software. The detailed interpretation of the vibrational spectra has been carried out by VEDA program. NBO analysis, Mulliken charge analysis, HOMO-LUMO, MEP, Global chemical reactivity descriptors and thermodynamic properties have been analyzed. The hyperpolarisability calculation reveals the present material has a reasonably good propensity for nonlinear optical activity. The obtained antimicrobial activity results indicate that the compound shows good to moderate activity against all tested bacterial and fungal pathogens. A computational study was also carried out to predict the drug-likeness and ADMET properties of the title compound. Due to the different potential biological activity of the title compound, molecular docking study is also reported and the compound might exhibit inhibitory activity against penicillin-binding protein PBP-2X.

  3. Substituent effects on the photolysis of methyl 2-carboxylate substituted aliphatic 2 H-azirines

    Science.gov (United States)

    Gómez-Zavaglia, Andrea; Kaczor, Agnieszka; Cardoso, Ana L.; Pinho e Melo, Teresa M. V. D.; Fausto, Rui

    2007-05-01

    In this study, the UV induced photochemical reactions of two 2 H-azirines - methyl 2-chloro-3-methyl-2 H-azirine-2-carboxylate (MCMAC) and methyl 3-methyl-2 H-azirine-2-carboxylate (MMAC) - isolated in argon matrices are compared. For both compounds, irradiation with λ > 235 nm led to observation of two primary photoprocesses: (a) C sbnd C bond cleavage, with production of nitrile ylides (P1-type products), and (b) C sbnd N bond cleavage, with production of methylated ketene imines (P2-type products). However, subsequent photoprocesses were found to be different in the two cases. In MCMAC, both primary photoproducts were shown to undergo further reactions: P1-type products decarboxylate, giving [(1-chloroethylidene)imino]ethanide, which bears a C dbnd N +dbnd C - group (P3-type product); P2-type products decarbonylate, yielding a substituted ylidene methanamine (P4-type product). In MMAC, only P2-type primary photoproducts appeared to react, undergoing decarbonylation or decarboxylation (both reactions leading to P4-type products), whereas P1-type products were found to be non-reactive. The non-observation of any secondary photoproduct resulting from photolysis of P1-MMAC revealed the higher photostability of this species when compared with the corresponding photoproduct obtained from MCMAC. The C sbnd N photochemical cleavage is an unusual process in aliphatic 2 H-azirines. In the studied compounds, its preference over the commonly observed C sbnd C azirine-ring bond photocleavage is attributed to the presence of electron withdrawing substituents (methylcarboxy group in both azirines and also the chlorine atom in MCMAC), which accelerates intersystem crossing towards the triplet state from where the cleavage of the C sbnd N bond takes place. The lack of the chlorine atom in MMAC may be partially compensated by the significantly higher stabilization of the P2-type photoproduct derived from this molecule ( ca. -52 kJ mol -1) relatively to the reactant, when

  4. Poly[dibromidobis[μ-1-(pyridin-4-ylmethyl-1H-1,2,4-triazole-κ2N:N′]cadmium

    Directory of Open Access Journals (Sweden)

    Xiu-Zhi Xu

    2011-02-01

    Full Text Available The title coordination polymer, [CdBr2(C8H8N42]n, arose from a layer-separated diffusion synthesis at room temperature. The title compound is isotypic with the I and Cl analogues. The Cd atom, located on an inversion center, is coordinated by two bromide ions and four N atoms (two from triazole rings and two from pyridyl rings in a distorted trans-CdBr2N4 octahedral arrangement. The bridging 1-(4-pyridylmethyl-1H-1,2,4-triazole ligands are twisted [dihedral angle between the triazole and pyridine rings = 72.56 (13°], affording a two-dimensional 44 sheet structure in the crystal.

  5. Quantification of four major metabolites of embryotoxic N-methyl- and N-ethyl-2-pyrrolidone in human urine by cooled-injection gas chromatography and isotope dilution mass spectrometry.

    Science.gov (United States)

    Schindler, Birgit K; Koslitz, Stephan; Meier, Swetlana; Belov, Vladimir N; Koch, Holger M; Weiss, Tobias; Brüning, Thomas; Käfferlein, Heiko U

    2012-04-17

    N-Methyl- and N-ethyl-2-pyrollidone (NMP and NEP) are frequently used industrial solvents and were shown to be embryotoxic in animal experiments. We developed a sensitive, specific, and robust analytical method based on cooled-injection (CIS) gas chromatography and isotope dilution mass spectrometry to analyze 5-hydroxy-N-ethyl-2-pyrrolidone (5-HNEP) and 2-hydroxy-N-ethylsuccinimide (2-HESI), two newly identified presumed metabolites of NEP, and their corresponding methyl counterparts (5-HNMP, 2-HMSI) in human urine. The urine was spiked with deuterium-labeled analogues of these metabolites. The analytes were separated from urinary matrix by solid-phase extraction and silylated prior to quantification. Validation of this method was carried out by using both, spiked pooled urine samples and urine samples from 56 individuals of the general population with no known occupational exposure to NMP and NEP. Interday and intraday imprecision was better than 8% for all metabolites, while the limits of detection were between 5 and 20 μg/L depending on the analyte. The high sensitivity of the method enables us to quantify NMP and NEP metabolites at current environmental exposures by human biomonitoring.

  6. A convenient method to synthesize N-[3H]methyl-N-nitrosocarbamate transfer reagents

    International Nuclear Information System (INIS)

    Mehta, P.; Gold, B.; Konakahara, T.

    1992-01-01

    Activated N-alkyl-N-nitrosocarbamates are useful acyl transfer reagents that are employed in the synthesis of N-alkyl-N-nitrosoureas and related N-nitroso compounds. The nitrosourea products are of chemical and biological interest because they provide access to the in situ generation of highly reactive carbonium type intermediates, which, depending on their structure, can be powerful carcinogens or antineoplastic agents. The availability of radiolabeled nitrosoureas greatly facilitates studies on their chemical and biological activities. Generally, the synthesis of activated nitrosocarbamates requires condensation of radiolabeled alkylisocyanates with the appropriate alcohol. Because radiolabeled alkylisocyanates are not commercially available and/or troublesome to synthesize, we have developed an easy and economical method for preparing N-[ 3 H]methyl-N-nitrosocarbamates suitable for use as transfer reagents utilizing 1,2,2,2-tetrachloroethyl chloroformate and [ 3 H]methylamine hydrochloride as starting materials. (author)

  7. Two complexes of Pt(IV) and Au(III) with 2,2'-dipyridylamine and 2,2'-dipyridylaminide ligands.

    Science.gov (United States)

    Chernyshev, Alexander N; Kukushkin, Vadim Yu; Haukka, Matti

    2014-12-01

    Two noble metal complexes involving ancillary chloride ligands and chelating 2,2'-bipyridylamine (Hdpa) or its deprotonated derivative (dpa), namely [bis(pyridin-2-yl-κN)amine]tetrachloridoplatinum(IV), [PtCl4(C10H9N3)], and [bis(pyridin-2-yl-κN)aminido]dichloridogold(III), [AuCl2(C10H8N3)], are presented and structurally characterized. The metal atom in the former has a slightly distorted octahedral coordination environment, formed by four chloride ligands and two pyridyl N atoms of Hdpa, while the metal atom in the latter has a slightly distorted square-planar coordination environment, formed by two chloride ligands and two pyridyl N atoms of dpa. The difference in conjugation between the pyridine rings in normal and deprotonated 2,2'-dipyridylamine is discussed on the basis of the structural features of these complexes. The influence of weak interactions on the supramolecular structures of the complexes, providing one-dimensional chains of [PtCl4(C10H9N3)] and dimers of [AuCl2(C10H8N3)], are discussed.

  8. Field-Induced Single-Ion Magnet Behaviour in Two New Cobalt(II Coordination Polymers with 2,4,6-Tris(4-pyridyl-1,3,5-triazine

    Directory of Open Access Journals (Sweden)

    Dong Shao

    2017-12-01

    Full Text Available We herein reported the syntheses, crystal structures, and magnetic properties of a two-dimensional coordination polymer {[CoII(TPT2/3(H2O4][CH3COO]2·(H2O4}n (1 and a chain compound {[CoII(TPT2(CHOO2(H2O2]}n (2 based on the 2,4,6-Tris(4-pyridyl-1,3,5-triazine (TPT ligand. Structure analyses showed that complex 1 had a cationic hexagonal framework structure, while 2 was a neutral zig-zag chain structure with different distorted octahedral coordination environments. Magnetic measurements revealed that both complexes exhibit large easy-plane magnetic anisotropy with the zero-field splitting parameter D = 47.7 and 62.1 cm−1 for 1 and 2, respectively. This magnetic anisotropy leads to the field-induced slow magnetic relaxation behaviour. However, their magnetic dynamics are quite different; while complex 1 experienced a dominating thermally activated Orbach relaxation at the whole measured temperature region, 2 exhibited multiple relaxation pathways involving direct, Raman, and quantum tunneling (QTM processes at low temperatures and Orbach relaxation at high temperatures. The present complexes enlarge the family of framework-based single-ion magnets (SIMs and highlight the significance of the structural dimensionality to the final magnetic properties.

  9. Drosophila mutations at the mei-9 and mus(2)201 loci which block excision of thymine dimers also block induction of unscheluded DNA synthesis by methyl methanesulfonate, ethyl methanesulfonate, N-methyl-N-nitrosourea, UV light and X-rays

    International Nuclear Information System (INIS)

    Dusenbery, R.L.; McCormick, S.C.; Smith, P.D.

    1983-01-01

    The mei-9 and mus(2)201 mutants of Drosophila melanogaster were identified as mutagen-sensitive mutants on the basis of larval hypersensitivity to methyl methanesulfonate and characterized as excision repair-deficient on the basis of a greatly reduced capacity to excise thymine dimers from cellular DNA. The high degree of larval cytotoxicity observed with a variety of other chemical and physical agents indicated that these mutants may be unable to excise other important classes of DNA adducts. We have measured the ability of the single mutants and the double mutant combination mei-9;mus(2)201 to perform the resynthesis step in excision repair by means of an autoradiographic analysis of unscheduled DNA synthesis (UDS) induced in a mixed population of primary cells in culture. The 3 strains exhibit no detectable UDS activity in response to applied doses of 1.5-6.0 mM methyl methanesulfonate, 1.0-4.5 nM N-methyl-N-nitrosourea or 10-40 J/m 2 254-nm UV light, dose ranges in which control cells exhibit a strong dose-dependent UDS response. The mei-9 and mei-9;mus(2)201 mutants also have no detectable UDS response to X-ray doses of 300-1.800 rad, whereas the mus(2)201 mutant exhibits a reduced, but dose-dependent, response over this range. These data correlate well with the degree of larval hypersensitivity of the strains and suggest that mutations at both loci block the excision repair of a wide variety of DNA damage prior to the resynthesis step. (orig.)

  10. N-Methyl Inversion and Accurate Equilibrium Structures in Alkaloids: Pseudopelletierine.

    Science.gov (United States)

    Vallejo-López, Montserrat; Écija, Patricia; Vogt, Natalja; Demaison, Jean; Lesarri, Alberto; Basterretxea, Francisco J; Cocinero, Emilio J

    2017-11-21

    A rotational spectroscopy investigation has resolved the conformational equilibrium and structural properties of the alkaloid pseudopelletierine. Two different conformers, which originate from inversion of the N-methyl group from an axial to an equatorial position, have been unambiguously identified in the gas phase, and nine independent isotopologues have been recorded by Fourier-transform microwave spectroscopy in a jet expansion. Both conformers share a chair-chair configuration of the two bridged six-membered rings. The conformational equilibrium is displaced towards the axial form, with a relative population in the supersonic jet of N axial /N equatorial ≈2/1. An accurate equilibrium structure has been determined by using the semiexperimental mixed-estimation method and alternatively computed by quantum-chemical methods up to the coupled-cluster level of theory. A comparison with the N-methyl inversion equilibria in related tropanes is also presented. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. File list: Oth.Lar.20.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Lar.20.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Larvae http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Lar.20.Adenine_N6-methylation.AllCell.bed ...

  12. File list: Oth.Adl.20.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Adl.20.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Adult http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Adl.20.Adenine_N6-methylation.AllCell.bed ...

  13. File list: Oth.Unc.10.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Unc.10.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Unclassified http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Unc.10.Adenine_N6-methylation.AllCell.bed ...

  14. File list: Oth.Unc.50.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Unc.50.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Unclassified http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Unc.50.Adenine_N6-methylation.AllCell.bed ...

  15. File list: Oth.Emb.50.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Emb.50.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Embryo http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Emb.50.Adenine_N6-methylation.AllCell.bed ...

  16. MethylMix 2.0: an R package for identifying DNA methylation genes.

    Science.gov (United States)

    Cedoz, Pierre-Louis; Prunello, Marcos; Brennan, Kevin; Gevaert, Olivier

    2018-04-14

    DNA methylation is an important mechanism regulating gene transcription, and its role in carcinogenesis has been extensively studied. Hyper and hypomethylation of genes is a major mechanism of gene expression deregulation in a wide range of diseases. At the same time, high-throughput DNA methylation assays have been developed generating vast amounts of genome wide DNA methylation measurements. We developed MethylMix, an algorithm implemented in R to identify disease specific hyper and hypomethylated genes. Here we present a new version of MethylMix that automates the construction of DNA-methylation and gene expression datasets from The Cancer Genome Atlas (TCGA). More precisely, MethylMix 2.0 incorporates two major updates: the automated downloading of DNA methylation and gene expression datasets from TCGA and the automated preprocessing of such datasets: value imputation, batch correction and CpG sites clustering within each gene. The resulting datasets can subsequently be analyzed with MethylMix to identify transcriptionally predictive methylation states. We show that the Differential Methylation Values created by MethylMix can be used for cancer subtyping. olivier.gevaert@stanford.edu. https://bioconductor.org/packages/release/bioc/manuals/MethylMix/man/MethylMix.pdf. MethylMix 2.0 was implemented as an R package and is available in bioconductor.

  17. Synthesis and characterization of 5,7-dimethyl-8-hydroxyquinoline and 2-(2-pyridyl)benzimidazole complexes of zinc(II) for optoelectronic application

    Science.gov (United States)

    Singh, Kapoor; Kumar, Amit; Srivastava, Ritu; Kadyan, Partap S.; Kamalasanan, Modeeparampil N.; Singh, Ishwar

    2011-11-01

    Bis(5,7-dimethyl-8-hydroxyquinolinato)zinc(II) (Me 2q) 2Zn and 5,7-dimethyl-8-hydroxyquinolinato(2-(2-pyridyl)benzimidazole) zinc(II) Me 2q(pbi)Zn have been synthesized and characterized by various techniques. These metal complexes have high thermal stability (>300 °C) and high glass transition temperatures (>150 °C). The vacuum deposited films of these materials show good film forming property and are suitable for opto-electronic applications. Multilayered organic electroluminescent (EL) devices have been fabricated having structure ITO/α-NPD/zinc complex/BCP/Alq 3/LiF/Al, which produce emission with chromaticity having Commission Internationale d'Eclairage (CIE) coordinates x = 0.506 and y = 0.484 for (Me 2q) 2Zn; x = 0.47 and y = 0.52 for (Me 2q)(pbi)Zn complex. The electroluminescence spectra show peak emission centered at 572 and 561 nm respectively for these materials.

  18. Reduced DNA repair in mouse satellite DNA after treatment with methylmethanesulfonate, and N-methyl-N-nitrosourea.

    Science.gov (United States)

    Bodell, W J; Banerjee, M R

    1976-01-01

    We have measured DNA repair in mouse satellite and main band DNA as resolved by Ag+-Cs2SO4 centrifugation in response to treatment with the alkylating agents, methyl methanesulfonate, and N-methyl-N-nitrosourea. We find that there is a statistically significant lower incorporation of 3H-Tdr into the satellite DNA as compared to the main band at varying periods after treatment with the alkylating agents. This suggests a reduced repair activity in the satellite DNA. We have measured the extent of binding of 14C-methyl methanesulfonate to the satellite, and main band DNA, and no difference in binding was observed, indicating that the reduced repair activity of satellite DNA is not due to a difference in binding of alkylating agents. We believe that the reduced incorporation of 3H-Tdr into satellite DNA may be due to its location in the condensed chromatin fraction. PMID:184436

  19. New coordination polymers from 1D chain, 2D layer to 3D framework constructed from 1,2-phenylenediacetic acid and 1,3-bis(4-pyridyl)propane flexible ligands

    International Nuclear Information System (INIS)

    Xin Lingyun; Liu Guangzhen; Wang Liya

    2011-01-01

    The hydrothermal reactions of Cd, Zn, or Cu(II) acetate salts with H 2 PHDA and BPP flexible ligands afford three new coordination polymers, including [Cd(PHDA)(BPP)(H 2 O)] n (1), [Zn(PHDA)(BPP)] n (2), and [Cu 2 (PHDA) 2 (BPP)] n (3) (H 2 PHDA=1,2-phenylenediacetic acid, BPP=1,3-bis(4-pyridyl)propane). The single-crystal X-ray diffractions reveal that all three complexes feature various metal carboxylate subunits extended further by the BPP ligands to form a diverse range of structures, displaying a remarked structural sensitivity to metal(II) cation. Complex 1 containing PHDA-bridged binuclear cadmium generates 1D double-stranded chain, complex 2 results in 2D→2D interpenetrated (4,4) grids, and complex 3 displays a 3D self-penetrated framework with 4 8 6 6 8 rob topology. In addition, fluorescent analyses show that both 1 and 2 exhibit intense blue-violet photoluminescence in the solid state. - Graphical Abstract: We show diverse supramolecular frameworks based on the same ligands (PHDA and BPP) and different metal acetate salts including 1D double-stranded chain, 2D → 2D twofold interpenetrated layer, and 3D self-penetration networks. Highlights: → Three metal(II = 2 /* ROMAN ) coordination polymers were synthesized using H 2 PHDA and BPP. → The diversity of structures show a remarked sensitivity to metal(II) center. → Complexes show the enhancement of fluorescence compared to that of free ligand.

  20. Nitrato-complexes of Y(III), La(III), Ce(III), Pr(III), Nd(III), Sm(III), Gd(III), Tb(III), Dy(III) and Ho(III) with 2-(2'-pyridyl) benzimidazole

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, A; Singh, M P; Singh, V K

    1982-05-01

    The nitrato-complexes, (Y(PyBzH)/sub 2/(NO/sub 3/)/sub 2/)NO/sub 3/.H/sub 2/O and Nd, Sm, Gd, Tb, Dy, Ho ; n=1-3, m=0-0.5 ; PyBzh=2-(2 -pyridyl)benzimidazole) are formed on interaction of the ligand with metal nitrates in ethanol. The electrical conductance values (116-129 ohm/sup -1/cm/sup 2/mol/sup -1/) suggest 1:1 electrolyte-nature of the complexes. Magnetic moment values of Ce(2.53 B.M.), Pr(3.62 B.M.), Nd(3.52 B.M.), Sm(1.70 B.M.), Gd(8.06 B.M.), Tb(9.44 B.M.), Dy(10.56 B.M.) and Ho(10.51 B.M.) in the complexes confirm the positive state of the metals. Infrared evidences are obtained for the existance of both coordinated (C/sub 2/v) and uncoordinated (D/sub 3/h) nitrate groups. Electronic absorption spectra of Pr(III)-, Nd(III)-, Sm(III)-, Tb(III)-, Dy(III)- and Ho(III)-complexes have been analysed in the light of LSJ terms.

  1. Nitrato-complexes of Y(III), La(III), Ce(III), Pr(III), Nd(III), Sm(III), Gd(III), Tb(III), Dy(III) and Ho(III) with 2-(2'-pyridyl) benzimidazole

    International Nuclear Information System (INIS)

    Mishra, A.; Singh, M.P.; Singh, V.K.

    1982-01-01

    The nitrato-complexes, [Y(PyBzH) 2 (NO 3 ) 2 ]NO 3 .H 2 O and Nd, Sm, Gd, Tb, Dy, Ho ; n=1-3, m=0-0.5 ; PyBzh=2-(2 -pyridyl)benzimidazole] are formed on interaction of the ligand with metal nitrates in ethanol. The electrical conductance values (116-129 ohm -1 cm 2 mol -1 ) suggest 1:1 electrolyte-nature of the complexes. Magnetic moment values of Ce(2.53 B.M.), Pr(3.62 B.M.), Nd(3.52 B.M.), Sm(1.70 B.M.), Gd(8.06 B.M.), Tb(9.44 B.M.), Dy(10.56 B.M.) and Ho(10.51 B.M.) in the complexes confirm the terpositive state of the metals. Infrared evidences are obtained for the existance of both coordinated (C 2 v) and uncoordinated (D 3 h) nitrate groups. Electronic absorption spectra of Pr(III)-, Nd(III)-, Sm(III)-, Tb(III)-, Dy(III)- and Ho(III)-complexes have been analysed in the light of LSJ terms. (author)

  2. File list: Oth.ALL.20.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.ALL.20.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n All cell types http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.ALL.20.Adenine_N6-methylation.AllCell.bed ...

  3. N-succinimidyl 4-methyl-3-(tri-n-butylstannyl)benzoate: synthesis and potential utility for the radioiodination of monoclonal antibodies

    International Nuclear Information System (INIS)

    Garg, P.K.; Garg, S.; Zalutsky, M.R.

    1993-01-01

    N-Succinimidyl 4-methyl-3-(tri-n-butylstannyl)benzoate (MATE) was synthesized in two steps from 4-methyl-3-iodobenzoic acid. Radioiododestannylation of MATE proceeded more slowly than N-succinimidyl 3-(tri-n-butylstannyl)benzoate (ATE), but for reaction periods of 10 min, identical yields were obtained. Paired-label biodistribution studies were performed in mice with an intact monoclonal antibody and an F(ab') 2 fragment labeled using MATE, ATE and Iodogen. Thyroid uptake with MATE was low, comparable to that seen with ATE, and considerably lower than that observed when the Iodogen method was used. With the F(ab') 2 fragment, kidney uptake using MATE was 8-fold higher than that observed when either the ATE or Iodogen methods were used. (Author)

  4. Bis(2-methyl-4-nitroanilinium tetrachloridomercurate(II

    Directory of Open Access Journals (Sweden)

    Andreas Lemmerer

    2008-12-01

    Full Text Available The title compound, (C7H9N2O22[HgCl4], self-assembles into cationic organic bilayers containing the 2-methyl-4-nitroanilinium cations, sandwiched between anionic inorganic layers built up by the distorted tetrahedral [HgCl4]2− groups. The organic sheets are interlinked through weak C—H...O hydrogen bonds, while they interact with the anionic part via strong charge-assisted N+—H...Cl—Hg hydrogen bonds. The [HgCl4]2− anions are bisected by a mirror plane passing through the metal and two of the chloride ions.

  5. Palladium-pyridyl catalytic films: a highly active and recyclable catalyst for hydrogenation of styrene under mild conditions.

    Science.gov (United States)

    Gao, Shuiying; Li, Weijin; Cao, Rong

    2015-03-01

    Palladium-pyridyl catalytic films, (PdCl2/bpy)n, were created by alternating immersions of a substrate in PdCl2 and bpy (bpy=4, 4'-bipyridyl) solutions. The as-prepared (PdCl2/bpy)10 catalyst demonstrated a remarkable catalytic activity toward hydrogenation of styrene under mild conditions and the turnover frequency (TOF) is as high as 6944h(-1). Pd(II) ions of (PdCl2/bpy)n films are in situ reduced to Pd nanoparticles (NPs) during the hydrogenation of styrene process, which results in the catalytic activity of the films. The results of X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) further demonstrate that Pd(II) ions of (PdCl2/bpy)n films were gradually converted to Pd(0) states. The catalytic activity is related to bilayer numbers and the activity increases with the number of bilayers below 10 bilayers. The solid substrates coated with (PdCl2/bpy)n multilayer catalysts were easily removed from the reaction mixture without separation filtration. Moreover, (PdCl2/bpy)n catalysts were reused for 10 consecutive reactions without loss of activity. The present (PdCl2/bpy)n heterogeneous catalysts have the advantages of easy separation and good recyclability. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Tetrakis(6-methyl-2,2′-bipyridine-1κ2N,N′;2κ2N,N′;3κ2N,N′;4κ2N,N′-tetra-μ-nitrato-1:2κ2O:O′;2:3κ3O:O′,O′′;2:3κ3O,O′:O′′;3:4κ2O:O′-tetranitrato-1κ4O,O′;4κ2O,O′-tetralead(II

    Directory of Open Access Journals (Sweden)

    Roya Ahmadi

    2009-10-01

    Full Text Available In the tetranuclear centrosymmetric title compound, [Pb4(NO38(C11H10N24], irregular PbN2O5 and PbN2O4 coordination polyhedra occur. The heptacoordinated lead(II ion is bonded to two bidentate and one monodentate nitrate ion and one bidentate 6-methyl-2,2′-bipyridine (mbpy ligand. The six-coordinate lead(II ion is bonded to one bidentate and two monodentate nitrate anions and one mbpy ligand. In the crystal, bridging nitrate anions lead to infinite chains propagating in [111]. A number of C—H...O hydrogen bonds may stabilize the structure.

  7. Dibromidobis(N,N,N′,N′-tetra­methyl­thio­urea-κS)cadmium(II)

    Science.gov (United States)

    Nawaz, Sidra; Sadaf, Sana; Fettouhi, Mohammed; Fazal, Atif; Ahmad, Saeed

    2010-01-01

    In the title compound, [CdBr2(C5H12N2S)2], the CdII atom lies on a twofold rotation axis. It exhibits a distorted tetra­hedral coordination environment defined by two S atoms of two tetra­methyl­thio­urea (tmtu) ligands and two bromide ions. The crystal structure is consolidated by C—H⋯N and C—H⋯S hydrogen bonds. PMID:21588180

  8. Applicability of new spin trap agent, 2-diphenylphosphinoyl-2-methyl-3,4-dihydro-2H-pyrrole N-oxide, in biological system

    International Nuclear Information System (INIS)

    Karakawa, Tomohiro; Sato, Keizo; Muramoto, Yosuke; Mitani, Yoshihiro; Kitamado, Masataka; Iwanaga, Tatsuya; Nabeshima, Tetsuji; Maruyama, Kumiko; Nakagawa, Kazuko; Ishida, Kazuhiko; Sasamoto, Kazumi

    2008-01-01

    Electron spin resonance using spin-trapping is a useful technique for detecting direct reactive oxygen species, such as superoxide (O 2 .- ). However, the widely used spin trap 2,2-dimethyl-3,4-dihydro-2H-pyrrole N-oxide (DMPO) has several fundamental limitations in terms of half-life and stability. Recently, the new spin trap 2-diphenylphosphinoyl-2-methyl-3,4-dihydro-2H-pyrrole N-oxide (DPhPMPO) was developed by us. We evaluated the biological applicability of DPhPMPO to analyze O 2 .- in both cell-free and cellular systems. DPhPMPO had a larger rate constant for O 2 .- and formed more stable spin adducts for O 2 .- than DMPO in the xanthine/xanthine oxidase (X/XO) system. In the phorbol myristate acetate-activated neutrophil system, the detection potential of DPhPMPO for O 2 .- was significantly higher than that of DMPO (k DMPO = 13.95 M -1 s -1 , k DPhPMPO = 42.4 M -1 s -1 ). These results indicated that DPhPMPO is a potentially good candidate for trapping O 2 .- in a biological system

  9. Facile Synthesis of CeO2-LaFeO3 Perovskite Composite and Its Application for 4-(Methylnitrosamino-1-(3-Pyridyl-1-Butanone (NNK Degradation

    Directory of Open Access Journals (Sweden)

    Kaixuan Wang

    2016-04-01

    Full Text Available A facile and environmentally friendly surface-ion adsorption method using CeCO3OH@C as template was demonstrated to synthesize CeO2-LaFeO3 perovskite composite material. The obtained composite was characterized by X-ray diffraction (XRD, fourier transform infrared spectra (FT-IR, field-emission scanning electron microscopy (FE-SEM, transmission electron microscopy (TEM, thermo-gravimetric analysis and differential scanning calorimetry (TG-DSC, N2 adsorption/desorption isotherms and X-ray photoelectron spectra (XPS measurements. The catalytic degradation of nitrosamine 4-(methylnitrosamino-1-(3-pyridyl-1-butanone (NNK was tested to evaluate catalytic activity of the CeO2-LaFeO3 composite. Much better activity was observed for the CeO2-LaFeO3 composite comparing with CeO2 and LaFeO3. These results suggested that perovskite composite materials are a promising candidate for the degradation of tobacco-specific nitrosamines (TSNAs.

  10. Ethyl 13-(4-chlorophenyl-11-methyl-6-oxo-5-phenyl-8-thia-3,4,5,10-tetraazatricyclo[7.4.0.02,7]trideca-1(9,2(7,3,10,12-pentaene-12-carboxylate

    Directory of Open Access Journals (Sweden)

    Elham A. Al-Taifi

    2016-05-01

    Full Text Available In the title molecule, C24H17ClN4O3S, the central tricyclic moiety is twisted slightly, as indicated by the dihedral angles of 4.86 (5 and 0.97 (6°, respectively, between the five-membered ring and the C3N3 and pyridyl rings. Additionally, the chlorobenzene ring makes a dihedral angle of 65.80 (5° with the pyridyl ring. Weak C—H...O, C—Cl...N [3.0239 (13 Å] and π–π stacking interactions [inter-centroid distance between thienyl rings = 3.6994 (8 Å, and between thienyl and pyridyl rings = 3.7074 (8 Å] contribute to the molecular packing. The ethyl group in the ester moiety is disordered over two sets of sites, with the major component having an occupancy of 0.567 (11.

  11. Insight into the theoretical and experimental studies of 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone N(4)-methyl-N(4)- phenylthiosemicarbazone - A potential NLO material

    Science.gov (United States)

    Sangeetha, K. G.; Aravindakshan, K. K.; Safna Hussan, K. P.

    2017-12-01

    The synthesis, geometrical parameters, spectroscopic studies, optimised molecular structure, vibrational analysis, Mullikan population analysis, MEP, NBO, frontier molecular orbitals and NLO effects of 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone N-(4)-methyl-N-(4)-phenylthiosemicarbazone, C25H23N5OS (L1) have been communicated in this paper. A combined experimental and theoretical approach was used to explore the structure and properties of the compound. For computational studies, Gaussian 09 program was used. Starting geometry of molecule was taken from X-ray refinement data and has been optimized by using DFT (B3LYP) method with the 6-31+G (d, p) basis sets. NBO analysis gave insight into the strongly delocalized structure, responsible for the nonlinearity and hence the stability of the molecule. Frontier molecular orbitals have been defined to forecast the global reactivity descriptors of L1. The computed first-order hyperpolarizability (β) of the compound is 2 times higher than that of urea and this account for its nonlinear optical property. Simultaneously, a molecular docking study of the compound was performed using GLIDE Program. For this, three biological enzymes, histone deacetylase, ribonucleotide reductase and DNA methyl transferase, were selected as receptor molecules.

  12. N-methylation of the heterogeneous nuclear ribonucleoproteins in HeLa cells

    International Nuclear Information System (INIS)

    Rieker, J.P.

    1984-01-01

    Several of the core proteins on the 40S heterogeneous nuclear ribonucleoprotein particles (hnRNP) from HeLa cells contain N/sup G/,N/sup G/-dimethyl-L-arginine (uDMA). 3-deazaadenosine (c 3 Ado), an inhibitor of and substrate for s-adenosyl-L-homocysteine hydrolase, has been used to study the methylation patterns of the individual polypeptides. Trimethyllysine and uDMA formation in total cellular protein were inhibited in the presence of the drug while other methylated basic amino acids were unaffected. This inhibition was reversed within 60 min after removal of the drug from the medium. Monolayer HeLa cultures were incubated with [methyl- 3 H]-L-methoinine for 12 hours in the presence of 50 uM c 3 Ado. Purified particles were obtained by centrifugation of nuclear extracts on sucrose density gradients. The core proteins were isolated by two-dimensional gel electrophoresis, acid hydrolyzed and analyzed for radioactivity incorporated into methionine and methylated basic amino acids. The ratio of radioactivity incorporated into uDMA relative to that into methionine for the two major particle proteins with molecular weights of 31,000 (A 1 ) and 43,000 (A 2 ) was about 2.0 and 0.2 in control cultures. In the presence of c 3 Ado, these ratios were depressed 60 to 80%. Results of pulse-chase experiments suggested that A 1 and A 2 are metabolically stable proteins (t/sub 0.5/ > 75 hr), whether or not the proteins were undermethylated. Monomethyl-L-arginine may be a precursor in the formation of u-DMA

  13. N-[5-Methyl-2-(2-nitrophenyl-4-oxo-1,3-thiazolidin-3-yl]pyridine-3-carboxamide monohydrate

    Directory of Open Access Journals (Sweden)

    Mehmet Akkurt

    2011-02-01

    Full Text Available In the title compound, C16H14N4O4S·H2O, the benzene and pyridine rings make a dihedral angle of 85.8 (1°. Both enantiomers of the chiral title compound are statistically disordered over the same position in the unit cell. The methyl and carbonyl group attached to the stereogenic center (C5 of the thiazolidine ring were therefore refined with common site-occupation factors of 0.531 (9 and 0.469 (9, respectively, for each stereoisomer. In the crystal, intermolecular N—H...O, O—H...O and O—H...N hydrogen bonds link the molecules, forming a three-dimensional supramolecular network. The crystal structure further shows π–π stacking interactions [centroid–centroid distance = 3.5063 (13 Å] between the pyridine rings.

  14. Synthesis of N-methyl-N-nitrosourea linked to a methidium chloride analogue and its reactions with 32P-end-labeled DNA

    International Nuclear Information System (INIS)

    Konakahara, T.; Wurdeman, R.L.; Gold, B.

    1988-01-01

    The synthesis and characterization of an N-methyl-N-nitrosourea (MNU) analogue that is covalently linked to methidium nucleus (9) is described. At 37/degrees/C in pH 8.0 buffer 9 hydrolyzes via pseudo-first-order kinetics, with a calculated t/sub 1/2/ = 77 min. By use of polyacrylamide sequencing gels the formation of piperidine-labile N 7 -methylguanine adducts from the reaction of 9 and MNU with 5'- 32 P-end-labeled DNA restriction fragments is reported. DNA methylation by 9 in 10 mM Tris buffer is enhanced with increasing ionic strength (50-200 mM NaCl), which contrasts to the inhibition of MNU-induced cleavage with increasing salt. In addition, 9 methylates all G sites equally, while MNU shows a clear preference for d(G)/sub n/ (n ≥ 3) runs and an asymmetrical methylation pattern within these G-rich regions. The results are discussed in terms of the delivery of the MNU moiety to the DNA target by a non-sequence-specific intercalation process and the subsequent hydrolytic generation of a nondiffusible alkylating intermediate

  15. Reinvestigation of the synthesis and evaluation of [N-methyl-11C]vorozole, a radiotracer targeting cytochrome P450 aromatase

    International Nuclear Information System (INIS)

    Kim, Sung Won; Biegon, Anat; Katsamanis, Zachary E.; Ehrlich, Carolin W.; Hooker, Jacob M.; Shea, Colleen; Muench, Lisa; Xu Youwen; King, Payton; Carter, Pauline; Alexoff, David L.; Fowler, Joanna S.

    2009-01-01

    Introduction: We reinvestigated the synthesis of [N-methyl- 11 C]vorozole, a radiotracer for aromatase, and discovered the presence of an N-methyl isomer which was not removed in the original purification method. Herein we report the preparation and positron emission tomography (PET) studies of pure [N-methyl- 11 C]vorozole. Methods: Norvorozole was alkylated with [ 11 C]methyl iodide as previously described and also with unlabeled methyl iodide. A high-performance liquid chromatography (HPLC) method was developed to separate the regioisomers. Nuclear magnetic resonance (NMR) spectroscopy ( 13 C and 2D-nuclear Overhauser effect spectroscopy NMR) was used to identify and assign structures to the N-methylated products. Pure [N-methyl- 11 C]vorozole and the contaminating isomer were compared by PET imaging in the baboon. Results: Methylation of norvorozole resulted in a mixture of isomers (1:1:1 ratio) based on new HPLC analysis using a pentafluorophenylpropyl bonded silica column, in which vorozole coeluted one of its isomers under the original HPLC conditions. Baseline separation of the three labeled isomers was achieved. The N-3 isomer was the contaminant of vorozole, thus correcting the original assignment of isomers. PET studies of pure [N-methyl- 11 C]vorozole with and without the contaminating N-3 isomer revealed that only [N-methyl- 11 C]vorozole binds to aromatase. [N-methyl- 11 C]Vorozole accumulated in all brain regions with highest accumulation in the aromatase-rich amygdala and preoptic area. Accumulation was blocked with vorozole and letrozole consistent with reports of some level of aromatase in many brain regions. Conclusions: The discovery of a contaminating labeled isomer and the development of a method for isolating pure [N-methyl- 11 C]vorozole combine to provide a new scientific tool for PET studies of the biology of aromatase and for drug research and development.

  16. Calorimetric investigations of hydrogen bonding in binary mixtures containing pyridine and its methyl-substituted derivatives. II. The dilute solutions of methanol and 2-methyl-2-propanol

    International Nuclear Information System (INIS)

    Marczak, Wojciech; Heintz, Andreas; Bucek, Monika

    2004-01-01

    Enthalpies of solution of methanol and 2-methyl-2-propanol (tert-butanol) in pyridine and its methyl derivatives were investigated in the range of mole fractions of alcohol x≤0.02 at temperature 298.15 K by a titration calorimeter. Dissolution of methanol is an exothermic process, with heat effects very close to those for water reported in part I of this study. The negative enthalpy of solution increases in the following order: pyridine < 3-methylpyridine < 4-methylpyridine < 2-methylpyridine < 2,6-dimethylpyridine < 2,4,6-trimethylpyridine. Positive enthalpies of solution of 2-methyl-2-propanol increase as follows: 2-methylpyridine < 2,4,6-trimethylpyridine < 4-methylpyridine < 2,6-dimethylpyridine < 3-methylpyridine < pyridine. The propensity of pyridine derivatives to hydrogen bonding is enhanced by the ortho effect. Methyl groups are probably too small to prevent the nitrogen atom in the pyridine ring from hydrogen bonding. However, spacious hydrocarbon group in 2-methyl-2-propanol molecule makes the bonding difficult for 2,6-dimethylpyridine and 2,4,6-trimethylpyridine, thus the number of O-H···N bonds is smaller than that in the solutions of methanol or water. The two latter seem to be very close to each other

  17. [(6-Methyl-2-pyridylmethyl(2-pyridylmethylamine][(2-pyridylmethylamine]copper(II bis(perchlorate

    Directory of Open Access Journals (Sweden)

    Ray J. Butcher

    2008-01-01

    Full Text Available The title compound, [Cu(C6H8N2(C13H15N3](ClO42, is a mixed ligand complex with the CuII atom coordinated by (6-methyl-2-pyridylmethyl(2-pyridylmethylamine, acting as a tridentate ligand, and 2-(2-aminomethylpyridine, as a bidentate ligand, leading to an N5 square-pyramidal geometry. The amine H atoms are involved in hydrogen bonding to the perchlorate O atoms and there are extensive but weak intermolecular C—H...O interactions in the crystal structure. The perchlorate ions are each disordered over two positions, with site occupancies of 0.601 (8:0.399 (8 and 0.659 (11:0.341 (11.

  18. (Tris{2-[(5-hy­droxy­pyridin-2-yl-κN)methyl­idene­imino-κN]eth­yl}amine)­zinc dinitrate

    Science.gov (United States)

    Seredyuk, Maksym; Znovjyak, Kateryna O.; Haukka, Matti; Pavlenko, Vadim A.; Bokach, Nadezhda A.

    2011-01-01

    In the complex cation of the title compound, [Zn(C24H27N7O3)](NO3)2, the tripodal tris­{[2-(5-hy­droxy­pyridin-2-yl)methyl­idene­imino]­eth­yl}amine ligand is coordin­ated to the Zn atom through the three pyridine and three imino N atoms. The coordination sphere of the Zn atom is based on an octahedron with a significant distortion towards trigonal prismatic, the twist angle being 45.58 (9)°. The crystal packing is formed by L and D anti­podes arranged in layers disposed parallel to the b axis. Strong O—H⋯O hydrogen bonding exists between the hy­droxy groups of the ligand and the nitrate anion. PMID:22199579

  19. Binuclear complexes of technetium. Evidence for bis(terdentate)bidentate coordination by the bridging ligand 2,3,5,6-tetrakis(2-pyridyl)pyrazine to technetium(V)

    International Nuclear Information System (INIS)

    Du Preez, J.G.H.; Gerber, T.I.A.; Gibson, M.L.; Geyser, R.

    1990-01-01

    The authors have used the potentially bis(terdentate) nitrogen aromatic heterocyclic ligand 2,3,5,6-tetrakis(2-pyridyl)pyrazine (tppz) to prepare mono- and bimetallic technetium(V) complexes bound to tppz. The stimulus for the development of the coordination chemistry of the man-made element technetium is provided by the use of complexes of this element as anatomical imaging agents in nuclear medicine. Although the chemistry of technetium(V) with nitrogen donor ligands is well understood, no complexes have been prepared using potentially terdentate neutral nitrogen donor ligands of this metal in the +5 oxidation state

  20. Weak maser emission of methyl formate toward Sagittarius B2(N) in the green bank telescope PRIMOS survey

    Energy Technology Data Exchange (ETDEWEB)

    Faure, A.; Wiesenfeld, L. [UJF-Grenoble 1/CNRS-INSU, Institut de Planétologie et d' Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble F-38041 (France); Remijan, A. J. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Szalewicz, K. [Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States)

    2014-03-10

    A non-LTE radiative transfer treatment of cis-methyl formate (HCOOCH{sub 3}) rotational lines is presented for the first time using a set of theoretical collisional rate coefficients. These coefficients have been computed in the temperature range 5-30 K by combining coupled-channel scattering calculations with a high accuracy potential energy surface for HCOOCH{sub 3}-He. The results are compared to observations toward the Sagittarius B2(N) molecular cloud using the publicly available PRIMOS survey from the Green Bank Telescope. A total of 49 low-lying transitions of methyl formate, with upper levels below 25 K, are identified. These lines are found to probe a presumably cold (∼30 K), moderately dense (∼10{sup 4} cm{sup –3}), and extended region surrounding Sgr B2(N). The derived column density of ∼4 × 10{sup 14} cm{sup –2} is only a factor of ∼10 larger than the column density of the trans conformer in the same source. Provided that the two conformers have the same spatial distribution, this result suggests that strongly non-equilibrium processes must be involved in their synthesis. Finally, our calculations show that all detected emission lines with a frequency below 30 GHz are (collisionally pumped) weak masers amplifying the continuum of Sgr B2(N). This result demonstrates the importance and generality of non-LTE effects in the rotational spectra of complex organic molecules at centimeter wavelengths.

  1. A convenient method to synthesize N-[[sup 3]H]methyl-N-nitrosocarbamate transfer reagents

    Energy Technology Data Exchange (ETDEWEB)

    Mehta, P.; Gold, B. (Nebraska Univ., Omaha, NE (United States). Eppley Inst. for Research in Cancer); Konakahara, T. (Science Univiversity of Tokyo, Noda, Chiba (Japan). Faculty of Science and Technology)

    1992-11-01

    Activated N-alkyl-N-nitrosocarbamates are useful acyl transfer reagents that are employed in the synthesis of N-alkyl-N-nitrosoureas and related N-nitroso compounds. The nitrosourea products are of chemical and biological interest because they provide access to the in situ generation of highly reactive carbonium type intermediates, which, depending on their structure, can be powerful carcinogens or antineoplastic agents. The availability of radiolabeled nitrosoureas greatly facilitates studies on their chemical and biological activities. Generally, the synthesis of activated nitrosocarbamates requires condensation of radiolabeled alkylisocyanates with the appropriate alcohol. Because radiolabeled alkylisocyanates are not commercially available and/or troublesome to synthesize, we have developed an easy and economical method for preparing N-[[sup 3]H]methyl-N-nitrosocarbamates suitable for use as transfer reagents utilizing 1,2,2,2-tetrachloroethyl chloroformate and [[sup 3]H]methylamine hydrochloride as starting materials. (author).

  2. Determination of methyl-, 2-hydroxyethyl- and 2-cyanoethylmercapturic acids as biomarkers of exposure to alkylating agents in cigarette smoke.

    Science.gov (United States)

    Scherer, Gerhard; Urban, Michael; Hagedorn, Heinz-Werner; Serafin, Richard; Feng, Shixia; Kapur, Sunil; Muhammad, Raheema; Jin, Yan; Sarkar, Mohamadi; Roethig, Hans-Juergen

    2010-10-01

    Alkylating agents occur in the environment and are formed endogenously. Tobacco smoke contains a variety of alkylating agents or precursors including, among others, N-nitrosodimethylamine (NDMA), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), acrylonitrile and ethylene oxide. We developed and validated a method for the simultaneous determination of methylmercapturic acid (MMA, biomarker for methylating agents such as NDMA and NNK), 2-hydroxyethylmercapturic acid (HEMA, biomarker for ethylene oxide) and 2-cyanoethylmercapturic acid (CEMA, biomarker for acrylonitrile) in human urine using deuterated internal standards of each compound. The method involves liquid/liquid extraction of the urine sample, solid phase extraction on anion exchange cartridges, derivatization with pentafluorobenzyl bromide (PFBBr), liquid/liquid extraction of the reaction mixture and LC-MS/MS analysis with positive electrospray ionization. The method was linear in the ranges of 5.00-600, 1.00-50.0 and 1.50-900 ng/ml for MMA, HEMA and CEMA, respectively. The method was applied to two clinical studies in adult smokers of conventional cigarettes who either continued smoking conventional cigarettes, were switched to test cigarettes consisting of either an electrically heated cigarette smoking system (EHCSS) or having a highly activated carbon granule filter that were shown to have reduced exposure to specific smoke constituents, or stopped smoking. Urinary excretion of MMA was found to be unaffected by switching to the test cigarettes or stop smoking. Urinary HEMA excretion decreased by 46 to 54% after switching to test cigarettes and by approximately 74% when stopping smoking. Urinary CEMA excretion decreased by 74-77% when switching to test cigarettes and by approximately 90% when stopping smoking. This validated method for urinary alkylmercapturic acids is suitable to distinguish differences in exposure not only between smokers and nonsmokers but also between smoking of conventional and

  3. Extraction of pentylbenzene from high molar mass alkanes (C{sub 14} and C{sub 17}) by N-methyl-2-pyrrolidone

    Energy Technology Data Exchange (ETDEWEB)

    Fandary, Mohamed S. [Chemical Engineering Department, College of Technological Studies, P.O. Box 3242, Salmyiah 22033 (Kuwait)]. E-mail: mfandary@yahoo.com; Al-Jimaz, Adel S. [Chemical Engineering Department, College of Technological Studies, P.O. Box 3242, Salmyiah 22033 (Kuwait); Al-Kandary, Jasem A. [Chemical Engineering Department, College of Technological Studies, P.O. Box 3242, Salmyiah 22033 (Kuwait); Fahim, Mohamed A. [Chemical Engineering Department, University of Kuwait, P.O. Box 5969, Safat 13060 (Kuwait)

    2006-04-15

    Equilibrium tie line data have been determined for the two ternary liquid systems: {l_brace}tetradecane, or heptadecane + pentylbenzene + N-methyl-2-pyrrolidone (NMP){r_brace} over a temperature range of (298 to 328) K. The two systems studied exhibit type I liquid + liquid phase diagram. The effect of temperature and n-alkane chain length upon solubility, selectivity, and distribution coefficients were investigated experimentally.

  4. Nicotine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone induce cyclooxygenase-2 activity in human gastric cancer cells: Involvement of nicotinic acetylcholine receptor (nAChR) and β-adrenergic receptor signaling pathways

    International Nuclear Information System (INIS)

    Shin, Vivian Yvonne; Jin, H.C.; Ng, Enders K.O.; Yu Jun; Leung, W.K.; Cho, C.H.; Sung, J.J.Y.

    2008-01-01

    Induction of cyclooxygenase-2 (COX-2) associates with cigarette smoke exposure in many malignancies. Nicotine and its derivative, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), are the two important components in cigarette smoke that contributes to cancer development. However, the molecular mechanism(s) by which nicotine or NNK promotes gastric carcinogenesis remains largely unknown. We found that nicotine and NNK significantly enhanced cell proliferation in AGS cells that expressed both alpha7 nicotinic acetylcholine receptor (α7 nAChR) and β-adrenergic receptors. Treatment of cells with α-bungarotoxin (α-BTX, α7nAChR antagonist) or propranolol (β-adrenergic receptor antagonist) blocked NNK-induced COX-2/PGE 2 and cell proliferation, while nicotine-mediated cell growth and COX-2/PGE 2 induction can only be suppressed by propranolol, but not α-BTX. Moreover, in contrast to the dependence of growth promoting effect of nicotine on Erk activation, inhibitor of p38 mitogen-activated protein kinase (MAPK) repressed NNK-induced COX-2 upregulation and resulted in suppression of cell growth. In addition, nicotine and NNK mediated COX-2 induction via different receptors to modulate several G1/S transition regulatory proteins and promote gastric cancer cell growth. Selective COX-2 inhibitor (SC-236) caused G1 arrest and abrogated nicotine/NNK-induced cell proliferation. Aberrant expression of cyclin D1 and other G1 regulatory proteins are reversed by blockade of COX-2. These results pointed to the importance of adrenergic and nicotinic receptors in gastric tumor growth through MAPK/COX-2 activation, which may perhaps provide a chemoprevention strategy for cigarette smoke-related gastric carcinogenesis

  5. 40 CFR 721.2275 - N,N,N′,N′-Tetrakis(oxi-ranyl- methyl)-1,3-cyclohexane di-meth-anamine.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false N,N,Nâ²,Nâ²-Tetrakis(oxi-ranyl- methyl... Significant New Uses for Specific Chemical Substances § 721.2275 N,N,N′,N′-Tetrakis(oxi-ranyl- methyl)-1,3... chemical substance identified as N,N,N′,N′-tetrakis(oxiranylmethyl)-1,3-cyclohexanedimethanamine (P-84-7...

  6. Ruthenium(II)-catalyzed direct addition of indole/pyrrole C2-H bonds to alkynes.

    Science.gov (United States)

    Liang, Libo; Fu, Shaomin; Lin, Dongen; Zhang, Xiao-Qi; Deng, Yuanfu; Jiang, Huanfeng; Zeng, Wei

    2014-10-17

    A ruthenium-catalyzed C2-hydroindolation of alkynes has been achieved. This protocol provides a rapid and concise access to kinds of 2-alkenyl-substituted N-(2-pyridyl)indoles in which the pyridyl moiety can be easily removed to afford free (N-H) indoles under mild conditions. Various arenes and alkynes, including electron-deficient and electron-rich internal alkynes and terminal alkynes, allow for this transformation.

  7. Di-μ-chlorido-bis{chlorido[(R/(S-1,5-diphenyl-3-(2-pyridyl-κN-2-pyrazoline-κN2]zinc(II}

    Directory of Open Access Journals (Sweden)

    Miquel Barceló-Oliver

    2010-08-01

    Full Text Available In the centrosymmetric binuclear title compound, [Zn2Cl4(C20H17N32], the coordination geometry of the ZnII ion can be described as a distorted ZnN2Cl3 trigonal bipyramid (τ = 0.89, arising from the N,N′-bidentate ligand, a terminal chloride ion and two bridging chloride ions. The N atoms occupy one axial and one equatorial site and the terminal chloride ion occupies an equatorial site. The dihedral angle between the pyridine and pyrazole rings is 12.8 (2°. In the crystal, aromatic π–π stacking [centroid–centroid separations = 3.812 (3 and 3.848 (3 Å] and C—H...Cl and C—H...π interactions help to establish the packing.

  8. Crystal structures and luminescence properties of two Cd(II) complexes based on 2-(1H-imidazol-1methyl)-6-methyl-1H-benzimidazole

    International Nuclear Information System (INIS)

    Zhang, Yuhong; Meng, Xiangru; Wen, Yu; Li, Peng; Ma, Lin; Zhang, Qiuju

    2015-01-01

    Two new complexes, {[Cd(immb)I 2 ].DMF} n (1) and {[Cd 3 (immb)(btc) 2 ]. H 2 O} n (2) (immb = 2-(1H-imidazol- 1-methyl)-6-methyl-1H-benzimidazole, btc = 1,2,3-benzenetricarboxylate, DMF = dimethyl formamide), have been synthesized and characterized. Single crystal X-ray diffraction shows that 1 exhibits a chain structure constructed by immb ligands bridging Cd(II) ions. In 2, Cd(II) ions are linked by immb ligands with bridging mode and btc3- anions with the μ 22 :η 1 bonding pattern leading to a 2D structure. Luminescent properties have been investigated in the solid state at room temperature.

  9. Morita-Baylis-Hillman Route to Dimethyl 2,3-Dihydrobenzo[b]oxepine-2,4- dicarboxylates and Methyl 2-(2-Carbomethoxybenzo[b]furan-3-yl)propanoates from Salicylaldehydes

    International Nuclear Information System (INIS)

    Ahn, Sang Hyun; Jang, Seung Soon; Kim, Young Keun; Lee, Kee Jung

    2012-01-01

    A new synthetic method for dimethyl 2,3-dihydrobenzo[b]oxepine-2,4-dicarboxylates and methyl 2-(2- carbomethoxybenzo[b]furan-3-yl)propanoates by an intramolecular conjugate displacement reaction or an S N 2 reaction of acetates of Morita-Baylis-Hillman adducts of methyl (2-formylphenoxy)acetates has been described

  10. Synthesis, Spectral and Antimicrobial Studies of Some N(2)-Substituted Tetrahydroindazoles

    International Nuclear Information System (INIS)

    Amirthaganesan, Shanmugasundaram; Aridoss, Gopalakrishnan; Park, Keun Soo; Lim, Kwon Taek; Jeong, Yeon Tae

    2010-01-01

    A series of N(2)-benzothiazolyl substituted tetrahydroindazoles has been synthesized via cyclic β keto esters. Optimum reaction condition was found as acidic toluene and effect of higher acidity towards substituted hydrazines in situ was described. Synthesized compounds have been achieved as single isomer and characterized by using 1D and 2D NMR spectral reports. Antimicrobial screening was carried out for the synthesized compounds along with a series of N(2)-pyridyl tetrahydroindazoles. 1 The results of the in vitro antimicrobial screening studies revealed that compounds 13, 16 against Staphylococcus aureus, 11 against Escherichia coli, 10-12, 16 against Pseudomonas aeruginosa and 12 against Klebsiella pneumoniae recorded almost two-fold better activity compared to the standard drug used

  11. Luminescently tagged 2,2'-bipyridine complex of FeII: synthesis and photophysical studies of 4-[N-(2-anthryl)carbamoyl]-4'-methyl-2,2'-bipyridine.

    Science.gov (United States)

    Zigler, David F; Elvington, Mark C; Heinecke, Julie; Brewer, Karen J

    2006-08-21

    The anthracene lumiphore was linked to the chelating ligand 2,2'-bipyridine, forming 4-[N-(2-anthryl)carbamoyl]-4'-methyl-2,2'-bipyridine (bpyAnth). Coupling through an amide linkage provides some electronic isolation of the anthracene lumiphore. Electrochemistry suggested little change of the anthracene oxidation whether free (1.35 V) linked to 2,2'-bipyridine as bpyAnth (1.30 V) or appended to Fe(II) (1.29 V). The bpyAnth ligand retained the structured luminescence characteristic of anthracene at 375, 400, 419, and 441 nm. This anthracene emission persists even when bpyAnth is complexed to an Fe(II) center. The complex [Fe(bpyAnth)3]2+ is emissive, in marked contrast to typical polyazine iron(II) complexes. This bpyAnth ligand serves as a luminescently tagged analogue of 2,2'-bipyridine, useful for coordination to a variety of metals.

  12. Synthesis, crystal structure, antibacterial activity and theoretical studies on a novel mononuclear cobalt(II) complex based on 2,4,6-tris(2-pyridyl)-1,3,5-triazine ligand

    Science.gov (United States)

    Maghami, Mahboobeh; Farzaneh, Faezeh; Simpson, Jim; Ghiasi, Mina; Azarkish, Mohammad

    2015-08-01

    A cobalt complex was prepared from CoCl2·6H2O and 2,4,6-tris(2-pyridyl)-1,3,5-triazine (tptz) in methanol and designated as [Co(tptz)(CH3OH)Cl2]·CH3OH·0.5H2O (1). It was characterized by several techniques including TGA analysis and FT-IR, UV-Vis and 1H NMR spectral studies. The crystal structure of 1 was determined by single-crystal X-ray diffraction. The Co(II) metal center in 1 is six coordinated with a distorted octahedral geometry. The tptz ligand is tridentate and coordinates to the cobalt through coplanar nitrogen atoms from the triazine and two pyridyl rings. Two chloride anions and a methanol molecule complete the inner coordination sphere of the metal ion. The optimized geometrical parameters obtained by DFT calculation are in good agreement with single XRD data. The in vitro antibacterial activity of various tptz complexes of Co(II), Ni(II), Cu(II), Mn(II) and Rh(III) were evaluated against Gram-positive (Bacillus subtilis, Staphylococcus aureus and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. Whereas all complexes exhibited good activity in comparison to standard antibacterial drugs, the inhibitory effects of complexes were found to be more than that of the parent ligand. Overall, the obtained results strongly suggest that the cobalt(II) complex is a suitable candidate for counteracting antibiotic resistant microorganisms.

  13. Theoretical study on the electronic structures and phosphorescent properties of a series of iridium(III) complexes with the different positional N-substitution in the pyridyl moiety

    Energy Technology Data Exchange (ETDEWEB)

    Han, Deming; Hao, Fengqi [School of Life Science and Technology, Changchun University of Science and Technology, Changchun 130022 (China); Tian, Jian [Clean Energy Technology Laboratory, Changchun University of Science and Technology, Changchun 130022 (China); Pang, Chunying; Li, Jingmei [School of Life Science and Technology, Changchun University of Science and Technology, Changchun 130022 (China); Zhao, Lihui, E-mail: zhaolihui@yahoo.com [School of Life Science and Technology, Changchun University of Science and Technology, Changchun 130022 (China); Zhang, Gang [State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130023 (China)

    2015-03-15

    The geometry structures, electronic structures, absorption and phosphorescent properties of a series of iridium(III) complexes with the different N-substitution cyclometalating ligand and the same benzyldiphenylphosphine auxiliary ligand have been theoretically investigated by using the density functional theory method. The lowest energy absorption wavelengths are located at 378 nm for A, 430 nm for B, 411 nm for C, 436 nm for D, and 394 nm for E. The introduction of N atom substitution at 1-, 2-, 3-, and 4-positions on the pyridyl moiety of complex A leads to an obvious redshifted absorption. The lowest energy emissions for complexes A–E are localized at 450, 409, 438, 483, and 429 nm, respectively, simulated in CH{sub 2}Cl{sub 2} medium at M052X level. Ionization potential and electron affinity have been calculated to evaluate the injection abilities of holes and electrons into these complexes. For complex C, the calculated results showed that it can possibly possess the larger radiative decay rate (k{sub r}) value than those of other four complexes. It is anticipated that the theoretical studies can provide valuable information for designing new phosphorescent metal complexes of organic light-emitting diodes. - Highlights: • Five Ir(III) complexes have been theoretically investigated. • The effect of N-substitution cyclometalating ligand has been studied. • The complex C possibly possesses the largest radiative decay rate value.

  14. Synthesis and characteristics in tumor-bearing mice of N-[11C]methyl-1-deoxynojirimycin and N-[11C]methyl-1-deoxymannojirimycin

    International Nuclear Information System (INIS)

    Ishiwata, Kiichi; Sasaki, Toru; Ishii, Shin-ichi; Senda, Michio; Seki, Hiroyuki; Kitasato Univ.; Nozaki, Tadashi

    1993-01-01

    N-[ 11 C]Methyl-1-deoxynojirimycin ([ 11 C]MDNM) and N-[ 11 C]methyl-1-deoxymannojirimycin ([ 11 C]MDMM) were prepared by 11 C-methylation of 1-deoxynojirimycin (DNM) and 1-deoxymannojirimycin (DMM), which are specific inhibitors of glucosidase and mannosidase, respectively. In mice bearing Ehrich ascitic tumor, the highest uptake of the [ 11 C]MDNM was observed in the kidney, followed by the liver and small intestine, while the tumour uptake was moderate. By MDNM loading, saturable uptake was observed in these tissues. In homogenates of the kidney and tumor tissues, a considerable amount of radioactivity was detected in a high-molecular weight fraction. These results demonstrate that the [ 11 C]MDNM has a potential for imaging the glucosidase activity by positron emission tomography. On the other hand, [ 11 C]MDMM showed lower uptake than [ 11 C]MDNM in the kidney, liver and small intestine and no effect of carrier DMM, suggesting that the [ 11 C]MDMM would not reflect mannosidase activity. (Author)

  15. Synthesis of 1-Methyl-3-oxo-7-oxabicyclo[2.2.1]hept-5-ene-2-carboxylic Acid Methyl Ester

    Directory of Open Access Journals (Sweden)

    Gil Valdo José da Silva

    2005-11-01

    Full Text Available A simple and efficient method for the preparation of 1-methyl-3-oxo-7- oxabicyclo[2.2.1]hept-5-en-2-carboxylic acid methyl ester (1 is described. The first step is a highly regioselective Diels-Alder reaction between 2-methylfuran and methyl-3-bromo- propiolate. A remarkably difficult ketal hydrolysis reaction was effected by treatment with HCl, a simple reagent that was shown to be more efficient, in this case, than commonly used more elaborate methods.

  16. Morita-Baylis-Hillman Route to Dimethyl 2,3-Dihydrobenzo[b]oxepine-2,4- dicarboxylates and Methyl 2-(2-Carbomethoxybenzo[b]furan-3-yl)propanoates from Salicylaldehydes

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Sang Hyun; Jang, Seung Soon; Kim, Young Keun; Lee, Kee Jung [Hanyang University, Seoul (Korea, Republic of)

    2012-01-15

    A new synthetic method for dimethyl 2,3-dihydrobenzo[b]oxepine-2,4-dicarboxylates and methyl 2-(2- carbomethoxybenzo[b]furan-3-yl)propanoates by an intramolecular conjugate displacement reaction or an S{sub N}2 reaction of acetates of Morita-Baylis-Hillman adducts of methyl (2-formylphenoxy)acetates has been described.

  17. Reinvestigation of the synthesis and evaluation of [N-methyl-{sup 11}C]vorozole, a radiotracer targeting cytochrome P450 aromatase

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Won [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States)], E-mail: swkim@bnl.gov; Biegon, Anat; Katsamanis, Zachary E. [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Ehrlich, Carolin W. [Johannes-Gutenberg Universitaet Mainz, Institut fuer Organische Chemie, Duesbergweg 10-14, Mainz (Germany); Hooker, Jacob M.; Shea, Colleen [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Muench, Lisa [National Institute on Alcoholism and Alcohol Abuse, Bethesda, MD (United States); Xu Youwen; King, Payton; Carter, Pauline; Alexoff, David L. [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Fowler, Joanna S. [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Department of Psychiatry, Mount Sinai School of Medicine, New York, NY (United States); Department of Chemistry, State University of New York at Stony Brook, Stony Brook, NY (United States)

    2009-04-15

    Introduction: We reinvestigated the synthesis of [N-methyl-{sup 11}C]vorozole, a radiotracer for aromatase, and discovered the presence of an N-methyl isomer which was not removed in the original purification method. Herein we report the preparation and positron emission tomography (PET) studies of pure [N-methyl-{sup 11}C]vorozole. Methods: Norvorozole was alkylated with [{sup 11}C]methyl iodide as previously described and also with unlabeled methyl iodide. A high-performance liquid chromatography (HPLC) method was developed to separate the regioisomers. Nuclear magnetic resonance (NMR) spectroscopy ({sup 13}C and 2D-nuclear Overhauser effect spectroscopy NMR) was used to identify and assign structures to the N-methylated products. Pure [N-methyl-{sup 11}C]vorozole and the contaminating isomer were compared by PET imaging in the baboon. Results: Methylation of norvorozole resulted in a mixture of isomers (1:1:1 ratio) based on new HPLC analysis using a pentafluorophenylpropyl bonded silica column, in which vorozole coeluted one of its isomers under the original HPLC conditions. Baseline separation of the three labeled isomers was achieved. The N-3 isomer was the contaminant of vorozole, thus correcting the original assignment of isomers. PET studies of pure [N-methyl-{sup 11}C]vorozole with and without the contaminating N-3 isomer revealed that only [N-methyl-{sup 11}C]vorozole binds to aromatase. [N-methyl-{sup 11}C]Vorozole accumulated in all brain regions with highest accumulation in the aromatase-rich amygdala and preoptic area. Accumulation was blocked with vorozole and letrozole consistent with reports of some level of aromatase in many brain regions. Conclusions: The discovery of a contaminating labeled isomer and the development of a method for isolating pure [N-methyl-{sup 11}C]vorozole combine to provide a new scientific tool for PET studies of the biology of aromatase and for drug research and development.

  18. Small Interfering RNA Specific for N-Methyl-D-Aspartate Receptor 2B Offers Neuroprotection to Dopamine Neurons through Activation of MAP Kinase

    Directory of Open Access Journals (Sweden)

    Olivia T.W. Ng

    2012-02-01

    Full Text Available In the present study, N-methyl-D-aspartate receptor 2B (NR2B-specific siRNA was applied in parkinsonian models. Our previous results showed that reduction in expression of N-methyl-D-aspartate receptor 1 (NR1, the key subunit of N-methyl-D-aspartate receptors, by antisense oligos amelio-rated the motor symptoms in the 6-hydroxydopamine (6-OHDA-lesioned rat, an animal model of Parkinson's disease (PD [Lai et al.: Neurochem Int 2004;45:11-22]. To further the investigation on the efficacy of gene silencing, small interference RNA (siRNA specific for the NR2B subunit was designed and administered in the striatum of 6-OHDA-lesioned rats. The present results show that administration of NR2B-specific siRNA decreased the number of apomorphine-induced rotations in the lesioned rats and that there was a significant reduction in NR2B proteins levels after NR2B-specific siRNA administration. Furthermore, attenuation of the loss of dopaminergic neurons was found in both the striatal and substantia nigra regions of the 6-OHDA-lesioned rats that had been continuously infused with siRNA for 7 days. In addition, a significant upregulation of p-p44/42 MAPK (ERK1/2; Thr202/Tyr204 and p-CREB (Ser133 in striatal neurons was found. These results suggest that application of the gene silencing targeting NR2B could be a potential treatment of PD, and they also revealed the possibility of NR2B-specific siRNA being involved in the prosurvival pathway.

  19. Rhodium-catalyzed NH insertion of pyridyl carbenes derived from pyridotriazoles: a general and efficient approach to 2-picolylamines and imidazo[1,5-a]pyridines.

    Science.gov (United States)

    Shi, Yi; Gulevich, Anton V; Gevorgyan, Vladimir

    2014-12-15

    A general and efficient NH insertion reaction of rhodium pyridyl carbenes derived from pyridotriazoles was developed. Various NH-containing compounds, including amides, anilines, enamines, and aliphatic amines, smoothly underwent the NH insertion reaction to afford 2-picolylamine derivatives. The developed transformation was further utilized in a facile one-pot synthesis of imidazo[1,5-a]pyridines. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Facile N-oxygenation of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine by the flavin-containing monooxygenase. A convenient synthesis of tritiated [methyl-3H]-4-phenyl-2,3-dihydropyridinium species

    International Nuclear Information System (INIS)

    Cashman, J.R.

    1988-01-01

    A rapid, efficient procedure useful for the radiosynthesis of [Me- 3 H]-MPDP+ ([methyl- 3 H]-4-phenyl-2,3-dihydropyridinium species) is described. Hog liver microsomes or the highly purified flavin-containing monooxygenase from hog liver quantitatively biotransforms [Me- 3 H]-MPTP to its corresponding radiolabeled N-oxide. For the small-scale synthesis required for radiolabeling procedures, this enzymatic process is superior to H 2 O 2 -mediated N-oxygenation of MPTP. In the presence of 0.5 mM NADPH, 4.5 mM n-octylamine, and 2 microCi [Me- 3 H]-MPTP, the only product detected in extracts from incubations performed with hog liver microsomes or purified hog liver flavin-containing monooxygenase is [Me- 3 H]-MPTP N-oxide. [Me- 3 H]-MPTP N-oxide is almost completely converted to [Me- 3 H]-MPDP+ by the action of trifluoroacetic anhydride. This procedure has the advantage of using a commercially available tritiated starting material, efficient transformations, and easily accomplished purification to afford a rapid synthesis of [Me- 3 H]-MPDP+

  1. Pediatric Opsoclonus-Myoclonus-Ataxia Syndrome Associated With Anti-N-methyl-D-aspartate Receptor Encephalitis.

    Science.gov (United States)

    Player, Brittany; Harmelink, Matthew; Bordini, Brett; Weisgerber, Michael; Girolami, Michael; Croix, Michael

    2015-11-01

    The full clinical spectrum of anti-N-methyl-D-aspartate receptor encephalitis is unknown in the pediatric population. We describe a previously healthy 4-year-old girl presenting with opsoclonus-myoclonus together with ataxia who had NR1-specific, anti-N-methyl-D-aspartate receptor antibodies in the cerebral spinal fluid. The presence of NR1-specific, anti-N-methyl-D-aspartate receptor antibodies in the setting of opsoclonus-myoclonus and ataxia syndrome may represent an expansion of the clinical presentations of anti-N-methyl-D-aspartate receptor encephalitis. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Analysis of the expression level and methylation of tumor protein p53, phosphatase and tensin homolog and mutS homolog 2 in N-methyl-N-nitrosourea-induced thymic lymphoma in C57BL/6 mice.

    Science.gov (United States)

    Huo, Xueyun; Li, Zhenkun; Zhang, Shuangyue; Li, Changlong; Guo, Meng; Lu, Jing; Lv, Jianyi; Du, Xiaoyan; Chen, Zhenwen

    2017-10-01

    Tumorigenesis is often caused by somatic mutation or epigenetic changes in genes that regulate aspects of cell death, proliferation and survival. Although the functions of multiple tumor suppressor genes have been well studied in isolation, how these genes cooperate during the progression of a single tumor remains unclear in numerous cases. The present study used N-methyl-N-nitrosourea (MNU), one of the most potent mutagenic nitrosourea compounds, to induce thymic lymphoma in C57BL/6J mice. Subsequently, the protein expression levels of phosphatase and tensin homolog (PTEN), transformation protein 53 and mutS homolog 2 (MSH2) were evaluated concomitantly in the thymus, liver, kidney and spleen of MNU-treated mice by western blotting. To determine whether changes in expression level were due to aberrant epigenetic regulation, the present study further examined the methylation status of each gene by MassARRAY analysis. During the tumorigenesis process of an MNU-induced single thymic lymphoma, the expression level of PTEN was revealed to be reduced in thymic lymphoma samples but not in normal or non-tumor thymus tissue samples. Furthermore, a marked reduction of P53 expression levels were demonstrated in thymic lymphomas and spleens with a metastatic tumor. Conversely, MSH2 upregulation was identified only in liver, kidney, and spleen samples that were infiltrated by thymic lymphoma cells. Furthermore, the present study revealed that a number of 5'-C-phosphate-G-3' sites located in the promoter of aberrantly expressed genes had significantly altered methylation statuses. These results improve the understanding of the course of mutagen-induced cancer, and highlight that epigenetic regulation may serve an important function in cancer.

  3. STUDIES ON THE INITIATION MECHANISM OF ORGANIC PEROXIDE AND N-METHACRYLOYLOXYETHYL-N-METHYL ANILINE IN METHYL METHACRYLATE POLYMERIZATION

    Institute of Scientific and Technical Information of China (English)

    QIU Kunyuan; GUO Dajie; GUO Xinqiu; FENG Xinde

    1990-01-01

    The initiation mechanism of methyl methacrylate (MMA) polymerization by organic peroxide and polymerizable aromatic tertiary amine such as N-methacryloyloxyethyl-N-methyi aniline (MEMA) binary system has been studied. The kinetics of polymerization of MMA and the ESR spectra of organic peroxide/MEMA system were determined. Based on the ESR study and the end-group analysis by UV spectra of the polymer formed, the initiation mechanism is proposed.

  4. Dopamine transporter binding in rat striatum: a comparison of [O-methyl-{sup 11}C]{beta}-CFT and [N-methyl-{sup 11}C]{beta}-CFT

    Energy Technology Data Exchange (ETDEWEB)

    Yoder, Karmen K.; Hutchins, Gary D.; Mock, Bruce H.; Fei, Xiangshu; Winkle, Wendy L. [Department of Radiology, Indiana University School of Medicine, L3-208, Indianapolis, IN 46202 (United States); Gitter, Bruce D.; Territo, Paul R. [Lilly Center for Anatomical and Molecular Imaging, Integrative Biology Division, Lilly Research Laboratories, Greenfield, IN 46140 (United States); Zheng Qihuang [Department of Radiology, Indiana University School of Medicine, L3-208, Indianapolis, IN 46202 (United States)], E-mail: qzheng@iupui.edu

    2009-01-15

    Introduction: Positron emission tomography scanning with radiolabeled phenyltropane cocaine analogs is important for quantifying the in vivo density of monoamine transporters, including the dopamine transporter (DAT). [{sup 11}C]{beta}-CFT is useful for studying DAT as a marker of dopaminergic innervation in animal models of psychiatric and neurological disorders. [{sup 11}C]{beta}-CFT is commonly labeled at the N-methyl position. However, labeling of [{sup 11}C]{beta}-CFT at the O-methyl position is a simpler procedure and results in a shorter synthesis time [desirable in small-animal studies, where specific activity (SA) is crucial]. In this study, we sought to validate that the O-methylated form of [{sup 11}C]{beta}-CFT provides equivalent quantitative results to that of the more commonly reported N-methyl form. Methods: Four female Sprague-Dawley rats were scanned twice on the IndyPET II small-animal scanner, once with [N-methyl-{sup 11}C]{beta}-CFT and once with [O-methyl-{sup 11}C]{beta}-CFT. DAT binding potentials (BP{identical_to}B'{sub avail}/K{sub d}) were estimated for right and left striata with a nonlinear least-squares algorithm, using a reference region (cerebellum) as the input function. Results: [N-Methyl-{sup 11}C]{beta}-CFT and [O-methyl-{sup 11}C]{beta}-CFT were synthesized with 40-50% radiochemical yields (HPLC purification). Radiochemical purity was >99%. SA at end of bombardment was 258{+-}30 GBq/{mu}mol. Average BP values for right and left striata with [N-methyl-{sup 11}C]{beta}-CFT were 1.16{+-}0.08 and 1.23{+-}0.14, respectively. BP values for [O-methyl-{sup 11}C]{beta}-CFT were 1.18{+-}0.08 (right) and 1.22{+-}0.16 (left). Paired t tests demonstrated that labeling position did not affect striatal DAT BP. Conclusions: These results suggest that [O-methyl-{sup 11}C]{beta}-CFT is quantitatively equivalent to [N-methyl-{sup 11}C]{beta}-CFT in the rat striatum.

  5. ac impedance, X-ray photoelectron spectroscopy and density functional theory studies of 3,5-bis(n-pyridyl)-1,2,4-oxadiazoles as efficient corrosion inhibitors for carbon steel surface in hydrochloric acid solution

    Energy Technology Data Exchange (ETDEWEB)

    Outirite, Moha; Lagrenee, Michel; Lebrini, Mounim [Unite de Catalyse et de Chimie du Solide, UMR-CNRS 8181, ENSCL, B.P. 90108, F-59652 Villeneuve d' Ascq Cedex (France); Traisnel, Michel; Jama, Charafeddine [Laboratoire des Procedes d' Elaboration des Revetements Fonctionnels, PERF UMR-CNRS 8008, ENSCL, B.P. 90108, F-59652 Villeneuve d' Ascq Cedex (France); Vezin, Herve [Laboratoire de Chimie Organique et Macromoleculaire, UMR-CNRS 8009, USTL Bat C4, F-59655 Villeneuve d' Ascq Cedex (France); Bentiss, Fouad, E-mail: fbentiss@enscl.f [Laboratoire de Chimie de Coordination et d' Analytique, Faculte des Sciences, Universite Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco)

    2010-02-01

    The corrosion inhibition properties of a new class of oxadiazole derivatives, namely 3,5-bis(n-pyridyl)-1,2,4-oxadiazoles (n-DPOX) for C38 carbon steel corrosion in 1 M HCl medium were analysed by electrochemical impedance spectroscopy (EIS). An adequate structural model of the interface was used and the values of the corresponding parameters were calculated and discussed. The experimental results showed that these compounds are excellent inhibitors for the C38 steel corrosion in acid solution and that the protection efficiency increased with increasing the inhibitors concentration. Electrochemical impedance data demonstrate that the addition of the n-DPOX derivatives in the corrosive solution decreases the charge capacitance and simultaneously increases the function of the charge/discharge of the interface, facilitating the formation of an adsorbed layer over the steel surface. Adsorption of these inhibitors on the steel surface obeys to the Langmuir adsorption isotherm. X-ray photoelectron spectroscopy (XPS) and the thermodynamic data of adsorption showed that inhibition of steel corrosion in normal hydrochloric solution by n-DPOX is due to the formation of a chemisorbed film on the steel surface. Quantum chemical calculations using the Density Functional Theory (DFT) and the Quantitative Structure Activity Relationship (QSAR) approach were performed on n-DPOX derivatives to determine the relationship between molecular structure and their inhibition efficiencies. The results of the quantum chemical calculations and experimental inhibition efficiency were subjected to correlation analysis and indicate that their inhibition effect is closely related to E{sub HOMO}, E{sub LUMO}, and dipole moment (mu).

  6. N-{4-[4-(4-Fluorophenyl-1-(2-methoxyethyl-2-methylsulfanyl-1H-imidazol-5-yl]-2-pyridyl}-2-methyl-3-phenylpropionamide

    Directory of Open Access Journals (Sweden)

    Stefan Laufer

    2009-12-01

    Full Text Available In the crystal structure of the title compound, C28H29FN4O2S, the imidazole ring makes dihedral angles of 11.85 (7, 73.33 (7 and 22.83 (8° with the 4-fluorophenyl, pyridine and phenyl rings, respectively. The 4-fluorophenyl ring makes dihedral angles of 77.91 (7 and 26.93 (8° with the pyridine and phenyl rings, respectively. The phenyl and pyridine rings are nearly perpendicular, making a dihedral angle of 86.47 (9°. The crystal packing shows an intermolecular N—H...O hydrogen-bonding interaction between the N—H and carbonyl groups of the amide functions.

  7. Poly[4,4'-(propane-1,3-diyl)dipyridinium bis{tetraaquabis(μ2-5-carboxybenzene-1,2,4-tricarboxylato)bis[μ2-1,3-bis(4-pyridyl)propane]dicobalt(II)} pentahydrate].

    Science.gov (United States)

    Atria, Ana María; Corsini, Gino; Garland, Maria Teresa; Baggio, Ricardo

    2011-11-01

    The title polymeric compound, {(C(13)H(16)N(2))[Co(C(10)H(3)O(8))(C(13)H(14)N(2))(H(2)O)(2)](2)·5H(2)O}(n), is an ionic structure comprising an anionic two-dimensional mesh characterized by a {[Co(Hbtc)(bpp)(H(2)O)(2)](-)}(2) motif [Hbtc is 5-carboxybenzene-1,2,4-tricarboxylate and bpp is 1,3-bis(4-pyridyl)propane], with interspersed 4,4'-(propane-1,3-diyl)dipyridinium cations, denoted (H(2)bpp)(2+), and water molecules providing the charge balance and structure stabilization. The reticular mesh consists of two independent types of [Co(H(2)O)(2)](2+) cationic nodes (lying on inversion centres), interconnected in the [101] direction by two independent sets of neutral bridging bpp ligands, both types of ligands being split by non-equivalent twofold axes. One set is formed by genuinely symmetric moieties, while those in the second set are only symmetric by disorder in the central propane bridge. These chains contain only one type of Co(II) centre and one type of bpp ligand; the metal cations therein are laterally bridged by Hbtc anions, thus forming transverse chains of alternating types of Co(II) cations. The elemental motif of the resulting grid is a highly distorted parallelogram, with metal-metal distances of 13.5242 (14) Å in the bpp direction and 9.105 (2) Å in the Hbtc direction, and a large internal angle of 138.42 (18)°. These two-dimensional structures have a profusion of hydrogen-bonding interactions with each other, either directly (with the aqua molecules as donors and the Hbtc anions as acceptors) or mediated by the unbound (H(2)bpp)(2+) cations and water molecules of hydration. These interactions generate a very complex hydrogen-bonding scheme involving all of the available N-H and O-H groups and which links these two-dimensional grids into a three-dimensional network.

  8. The involvement of poly(ADP-ribose) polymerase in the degradation of NAD caused by γ-radiation and N-methyl-N-nitrosourea

    International Nuclear Information System (INIS)

    Skidmore, C.J.; Davies, M.I.; Goodwin, P.M.; Halldorsson, H.; Lewis, P.J.; Shall, S.; Zia'ee, A.

    1979-01-01

    Both N-methyl-N-nitrosourea and γ-radiation lower cellular NAD in mouse leukaemia cells (L1210) in a dose-dependent way. The minimum NAD level is reached 2 h after a brief exposure to N-methyl-N-nitrosourea, but within 15 min of γ-irradiation. The cells remain metabolically active; they are able to recover their control NAD levels and are impermeable to trypan blue. Several inhibitors of poly(ADP-ribose) polymerase inhibit the drop in cellular NAD caused by these two agents: 2 mM 5-methylnicotinamide, 1 mM theophylline or 1 mM theobromine inhibit the effect of N-methyl-N-nitrosourea on cellular NAD level; 200 μM thymidine, 500 μM 5-methylnicotinaminde, 500 μM thephylline and 500 μM theobromine prevent the lowering of cellular NAD by γ-irradiation. The extent to which the drop in cellular NAD is inhibited is dependent on both the concentration of cytotoxic agent and of polymerase inhibitor. Caffeine will inhibit the drop in NAD but only at 10 mM, while nicotonic acid is ineffictive even at this dose. The activity of poly(ADP-ribose) polymerase is permeabilized cells immediately after γ-radiation increases with dose up to 12 krad, giving a maximal 3.4-fold stimulation of the enzyme activity, whereas the degradation of NAD under conditions optimal for NAD glycohydrolase does not change. The activity of the polymerase shows a close temporal correlation with the NAD drop following both γ-radiation and N-methyl-N-nitrosourea. The enzyme activity is maximal when the NAD content. (orig./AJ) 891 AJ/orig.- 892 HIS [de

  9. The methylcobalt(III) complex of a tetrapodal pentadentate amine ligand, 2,6-bis(1′,3′-diamino-2′-methyl-prop-2′-yl)pyridine

    DEFF Research Database (Denmark)

    Grohmann, Andreas; Heinemann, Frank W; Kofod, Pauli

    1999-01-01

    The pentaamine methylcobalt(III) compound [Co(pyN4)(CH3)](NO3)2 (pyN4=2,6-bis(1′,3′-diamino-2′-methyl-prop-2′-yl)pyridine) has been synthesised from [Co(NH3)5(CH3)](NO3)2 and pyN4 by ligand exchange, and characterised by IR, 1H, 13C and 59Co NMR spectroscopy as well as elemental analysis. The str......The pentaamine methylcobalt(III) compound [Co(pyN4)(CH3)](NO3)2 (pyN4=2,6-bis(1′,3′-diamino-2′-methyl-prop-2′-yl)pyridine) has been synthesised from [Co(NH3)5(CH3)](NO3)2 and pyN4 by ligand exchange, and characterised by IR, 1H, 13C and 59Co NMR spectroscopy as well as elemental analysis...... nitrogen atom, while the four equivalent primary amino groups take the equatorial positions. The other axial position, trans to the pyridine ring, is occupied by the methyl group. The Co–Npy bond length of 2.018(2) Å is significantly elongated compared with other cobalt(III) complexes of the pyN4 ligand...

  10. Radiosynthesis and radiopharmacological evaluation of [N-methyl-11C]Org 34850 as a glucocorticoid receptor (GR)-binding radiotracer

    International Nuclear Information System (INIS)

    Wuest, Frank; Kniess, Torsten; Henry, Brian; Peeters, Bernardus W.M.M.; Wiegerinck, Peter H.G.; Pietzsch, Jens; Bergmann, Ralf

    2009-01-01

    The radiosynthesis of [N-methyl- 11 C]Org 34850 as a potential brain glucocorticoid receptor (GR)-binding radiotracer is described. The radiosynthesis was accomplished via N-methylation of the corresponding desmethyl precursor with [ 11 C]methyl triflate in a remotely controlled synthesis module to give the desired compound in a radiochemical yield of 23±5% (decay-corrected, based upon [ 11 C]CO 2 ) at a specific activity of 47±12 GBq/μmol (n=15) at the end-of-synthesis (EOS). The radiochemical purity after semi-preparative HPLC purification exceeded 95%. The total synthesis time was 35-40 min after end-of-bombardment (EOB). The radiotracer is rapidly metabolized in rat plasma leading to the formation of two more hydrophilic metabolites as the major metabolites. Radiopharmacological evaluation involving biodistribution and small animal PET imaging in normal Wistar rats showed that the compound [N-methyl- 11 C]Org 34850 is not able to sufficiently penetrate the blood-brain barrier. Therefore, compound [N-methyl- 11 C]Org 34850 seems not to be a suitable PET radiotracer for imaging rat brain GRs. However, involvement of Pgp or species differences requires further clarification to establish whether the radiotracer [N-methyl- 11 C]Org 34850 may still represent a suitable candidate for imaging GRs in humans

  11. Radiosynthesis and radiopharmacological evaluation of [N-methyl-11C]Org 34850 as a glucocorticoid receptor (GR)-binding radiotracer.

    Science.gov (United States)

    Wuest, Frank; Kniess, Torsten; Henry, Brian; Peeters, Bernardus W M M; Wiegerinck, Peter H G; Pietzsch, Jens; Bergmann, Ralf

    2009-02-01

    The radiosynthesis of [N-methyl-(11)C]Org 34850 as a potential brain glucocorticoid receptor (GR)-binding radiotracer is described. The radiosynthesis was accomplished via N-methylation of the corresponding desmethyl precursor with [(11)C]methyl triflate in a remotely controlled synthesis module to give the desired compound in a radiochemical yield of 23+/-5% (decay-corrected, based upon [(11)C]CO(2)) at a specific activity of 47+/-12 GBq/micromol (n=15) at the end-of-synthesis (EOS). The radiochemical purity after semi-preparative HPLC purification exceeded 95%. The total synthesis time was 35-40 min after end-of-bombardment (EOB). The radiotracer is rapidly metabolized in rat plasma leading to the formation of two more hydrophilic metabolites as the major metabolites. Radiopharmacological evaluation involving biodistribution and small animal PET imaging in normal Wistar rats showed that the compound [N-methyl-(11)C]Org 34850 is not able to sufficiently penetrate the blood-brain barrier. Therefore, compound [N-methyl-(11)C]Org 34850 seems not to be a suitable PET radiotracer for imaging rat brain GRs. However, involvement of Pgp or species differences requires further clarification to establish whether the radiotracer [N-methyl-(11)C]Org 34850 may still represent a suitable candidate for imaging GRs in humans.

  12. Antimutagenic and anticarcinogenic effects of betel leaf extract against the tobacco-specific nitrosamine 4-(N-nitrosomethylamino)-1-(3-pyridyl)-1-butanone (NNK).

    Science.gov (United States)

    Bhide, S V; Padma, P R; Amonkar, A J

    1991-01-01

    Earlier studies showed that betel leaf inhibits the mutagenic action of standard mutagens like benzo[a]pyrene and dimethylbenz[a]anthracene. Since tobacco-specific nitrosamines are the major carcinogens present in unburnt forms of tobacco, we studied the effect of an extract of betel leaf on the mutagenic and carcinogenic actions of one of the most potent, 4-(N-nitrosomethylamino)-1-(3-pyridyl)-1-butanone (NNK). Betel-leaf extract and hydroxychavicol suppressed the mutagenicity of NNK in both the Ames and the micronucleus test. In studies in mice, betel-leaf extract reduced the tumorigenic effects of NNK by 25%. Concurrent treatment with the extract also inhibited the decreases in levels of vitamin A in liver and plasma induced by NNK. Betel leaf thus has protective effects against the mutagenic, carcinogenic and adverse metabolic effects of NNK in mice.

  13. A fast response cadmium-selective polymeric membrane electrode based on N,N'-(4-methyl-1,2-phenylene)diquinoline-2-carboxamide as a new neutral carrier.

    Science.gov (United States)

    Rezaei, B; Meghdadi, S; Zarandi, R Fazel

    2008-05-01

    A new polyvinylchloride membrane sensor for Cd(2+) ions based on N,N'-(4-methyl-1,2-phenylene)diquinoline-2-carboxamide (Mebqb) as a new and excellent neutral ionophore has been prepared. The sensor shows a Nernestian response for cadmium ions over a wide concentration range (1.0 x 10(-6) to 1.0 x 10(-1) M) with the determination coefficient of 0.9964 and slope of 29.9 +/- 0.5 mV decade(-1). The limit of detection is 8 x 10(-7) M. It has a fast response time of 3-8s and can be used for at least 8 weeks without any divergence in potential. The electrode can be used in the pH range from 4.0 to 9.0. The proposed sensor shows a very good discriminating ability towards Cd(2+) ion in comparison to some alkali, alkaline earth, transition and heavy metal ions. It was successfully applied for the direct determination of Cd(2+) in standard and real sample solutions.

  14. A fast response cadmium-selective polymeric membrane electrode based on N,N'-(4-methyl-1,2-phenylene)diquinoline-2-carboxamide as a new neutral carrier

    International Nuclear Information System (INIS)

    Rezaei, B.; Meghdadi, S.; Zarandi, R. Fazel

    2008-01-01

    A new polyvinylchloride membrane sensor for Cd 2+ ions based on N,N'-(4-methyl-1,2-phenylene)diquinoline-2-carboxamide (Mebqb) as a new and excellent neutral ionophore has been prepared. The sensor shows a Nernestian response for cadmium ions over a wide concentration range (1.0 x 10 -6 to 1.0 x 10 -1 M) with the determination coefficient of 0.9964 and slope of 29.9 ± 0.5 mV decade -1 . The limit of detection is 8 x 10 -7 M. It has a fast response time of 3-8 s and can be used for at least 8 weeks without any divergence in potential. The electrode can be used in the pH range from 4.0 to 9.0. The proposed sensor shows a very good discriminating ability towards Cd 2+ ion in comparison to some alkali, alkaline earth, transition and heavy metal ions. It was successfully applied for the direct determination of Cd 2+ in standard and real sample solutions

  15. Synthesis, in vitro validation and in vivo pharmacokinetics of [{sup 125}I]N-[2-(4-iodophenyl)ethyl]-N-methyl-2-(1-piperidinyl) ethylamine: A high-affinity ligand for imaging sigma receptor positive tumors

    Energy Technology Data Exchange (ETDEWEB)

    John, Christy S; Gulden, Mary E; Vilner, Bertold J; Bowen, Wayne D

    1996-08-01

    N-[2-(4-iodophenyl)ethyl]-N-methyl-2-(1-piperidinyl)ethylamine, IPEMP, and the corresponding bromo derivative, BrPEMP, have been synthesized and characterized. Both BrPEMP and IPEMP were evaluated for sigma-1 and sigma-2 subtype receptor affinities and found to possess very high affinities for both receptor subtypes. The precursor for radioiodination n-tributylstannylphenylethylpiperidinylethylamine was prepared from its bromo derivative by palladium-catalyzed stannylation reaction. Radioiodinated 4-[{sup 125}I]PEMP was readily prepared in high yields and high specific activity by oxidative iododestannylation reaction using chloramine-T as oxidizing agent. Sites labeled by 4-[{sup 125}I]PEMP in guinea pig brain membranes showed high affinity for BD1008, haloperidol, and (+)-pentazocine (Ki = 5.06 {+-} 0.40, 32.6 {+-} 2.75, and 48.1 {+-} 8.60 nM, respectively), which is consistent with sigma receptor pharmacology. Competition binding studies of 4-[{sup 125}I]PEMP in melanoma (A375) and MCF-7 breast cancer cells showed a high affinity, dose-dependent inhibition of binding with known sigma ligand N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(1-pyrrolidinyl) ethylamine, BD1008 (Ki = 5, 11 nM, respectively), supporting the labeling of sigma sites in these cells. Haloperidol, however showed a weaker (Ki 100-200 nM) affinity for the sites labeled by 4-[{sup 125}I]PEMP in these cells. Biodistribution studies of 4-[{sup 125}I]PEMP in rats showed a fast clearance of this radiopharmaceutical from blood, liver, lung, and other organs. A co-injection of 4-IPEMP with 4-[{sup 125}I]PEMP resulted in 37%, 69%, and 35% decrease in activity in liver, kidney, and brain (organs possessing sigma receptors), respectively at 1-h postinjection. These results suggest that 4-[{sup 125}I]PEMP is a promising radiopharmaceutical for pursuing further studies in animal models with tumors.

  16. From polyethylene waxes to HDPE using an α,α'-bis(arylimino)-2,3:5,6-bis(pentamethylene)pyridyl-chromium(iii) chloride pre-catalyst in ethylene polymerisation.

    Science.gov (United States)

    Huang, Chuanbing; Du, Shizhen; Solan, Gregory A; Sun, Yang; Sun, Wen-Hua

    2017-05-30

    Five examples of α,α'-bis(arylimino)-2,3:5,6-bis(pentamethylene)pyridyl-chromium(iii) chlorides (aryl = 2,6-Me 2 Ph Cr1, 2,6-Et 2 Ph Cr2, 2,6-i-Pr 2 Ph Cr3, 2,4,6-Me 3 Ph Cr4, 2,6-Et 2 -4-MePh Cr5) have been synthesized by the one-pot template reaction of α,α'-dioxo-2,3:5,6-bis(pentamethylene)pyridine, CrCl 3 ·6H 2 O and the corresponding aniline. The molecular structures of Cr1 and Cr4 reveal distorted octahedral geometries with the N,N,N-ligand adopting a mer-configuration. On activation with an aluminium alkyl co-catalyst, Cr1-Cr5 exhibited high catalytic activities in ethylene polymerization and showed outstanding thermal stability operating effectively at 80 °C with activities up to 1.49 × 10 7 g of PE (mol of Cr) -1 h -1 . Significantly, the nature of the co-catalyst employed had a dramatic effect on the molecular weight of the polymeric material obtained. For example, using diethylaluminium chloride (Et 2 AlCl) in combination with Cr4 gave high density/high molecular weight polyethylene with broad molecular weight distributions (30.9-39.3). By contrast, using modified methylaluminoxane (MMAO), strictly linear polyethylene waxes of lower molecular weight and narrow molecular weight distribution (1.6-2.0) were obtained with vinyl end-groups.

  17. Thermal Properties of Methyl Ester-Containing Poly(2-oxazolines

    Directory of Open Access Journals (Sweden)

    Petra J. M. Bouten

    2015-10-01

    Full Text Available This paper describes the synthesis and thermal properties in solution and bulk of poly(2-alkyl-oxazolines (PAOx containing a methyl ester side chain. Homopolymers of 2-methoxycarbonylethyl-2-oxazoline (MestOx and 2-methoxycarbonylpropyl-2-oxazoline (C3MestOx, as well as copolymers with 2-ethyl-2-oxazoline (EtOx and 2-n-propyl-2-oxazoline (nPropOx, with systematic variations in composition were prepared. The investigation of the solution properties of these polymers revealed that the cloud point temperatures (TCPs could be tuned in between 24 °C and 108 °C by variation of the PAOx composition. To the best of our knowledge, the TCPs of PMestOx and PC3MestOx are reported for the first time and they closely resemble the TCPs of PEtOx and PnPropOx, respectively, indicating similar hydrophilicity of the methyl ester and alkyl side chains. Furthermore, the thermal transitions and thermal stability of these polymers were investigated by DSC and TGA measurements, respectively, revealing amorphous polymers with glass transition temperatures between -1 °C and 54 °C that are thermally stable up to >300 °C.

  18. Crystal structure of bis-[N-(2-hy-droxy-eth-yl)-N-methyl-dithio-carbamato-κ2S,S'](pyridine)-zinc(II) pyridine monosolvate and its N-ethyl analogue.

    Science.gov (United States)

    Poplaukhin, Pavel; Tiekink, Edward R T

    2017-07-01

    The common structural feature of the title compounds, [Zn(C 4 H 8 NOS 2 ) 2 (C 5 H 5 N)]·C 5 H 5 N (I) and [Zn(C 5 H 10 NOS 2 ) 2 (C 5 H 5 N)]·C 5 H 5 N (II), which differ by having di-thio-carbamate N-bound methyl (I) and ethyl (II) groups, is the coordination of each Zn II atom by two non-symmetrically chelating di-thio-carbamate ligands and by a pyridine ligand; in each case, the non-coordinating pyridine mol-ecule is connected to the Zn-containing mol-ecule via a (hy-droxy)O-H⋯N(pyridine) hydrogen bond. The resulting NS 4 coordination geometry is closer to a square-pyramid than a trigonal bipyramid in the case of (I), but almost inter-mediate between the two extremes in (II). The mol-ecular packing features (hy-droxy)O-H⋯O(hy-droxy) hydrogen bonds, leading to supra-molecular chains with a zigzag arrangement along [10-1] (I) or a helical arrangement along [010] (II). In (I), π-π [inter-centroid distances = 3.4738 (10) and 3.4848 (10) Å] between coordinating and non-coordinating pyridine mol-ecules lead to stacks comprising alternating rings along the a axis. In (II), weaker π-π contacts occur between centrosymmetrically related pairs of coordinating pyridine mol-ecules [inter-centroid separation = 3.9815 (14) Å]. Further inter-actions, including C-H⋯π(chelate) inter-actions in (I), lead to a three-dimensional architecture in each case.

  19. N-[5-Methyl-2-(2-nitro-phen-yl)-4-oxo-1,3-thia-zolidin-3-yl]pyridine-3-carboxamide monohydrate.

    Science.gov (United States)

    Akkurt, Mehmet; Celik, Ismail; Demir, Hale; Ozkırımlı, Sumru; Büyükgüngör, Orhan

    2011-01-08

    In the title compound, C(16)H(14)N(4)O(4)S·H(2)O, the benzene and pyridine rings make a dihedral angle of 85.8 (1)°. Both enanti-omers of the chiral title compound are statistically disordered over the same position in the unit cell. The methyl and carbonyl group attached to the stereogenic center (C(5) of the thia-zolidine ring) were therefore refined with common site-occupation factors of 0.531 (9) and 0.469 (9), respectively, for each stereoisomer. In the crystal, inter-molecular N-H⋯O, O-H⋯O and O-H⋯N hydrogen bonds link the mol-ecules, forming a three-dimensional supra-molecular network. The crystal structure further shows π-π stacking inter-actions [centroid-centroid distance = 3.5063 (13) Å] between the pyridine rings.

  20. Semi-automated preparation of a 11C-labelled antibiotic - [N-methyl-11C]erythromycin A lactobionate

    International Nuclear Information System (INIS)

    Pike, V.W.; Palmer, A.J.; Horlock, P.L.; Liss, R.H.

    1984-01-01

    A fast semi-automated method is described for labelling the antibiotic, erythromycin A (1), with the short-lived positron-emitting radionuclide, 11 C(tsub(1/2)=20.4 min), in order to permit the non-invasive study of its tissue uptake in vivo. Labelling was achieved by the fast reductive methylation of N-demethylerythromycin A (2) with [ 11 C]formaldehyde, itself prepared from cyclotron-produced [ 11 C]-carbon dioxide. Rapid chemical and radiochemical purification of the [N-methyl- 11 C]erythromycin A (3) were achieved by HPLC and verified by TLC with autoradiography. The purified material was formulated for human i.v. injection as a sterile apyrogenic solution of the lactobionate salt. The preparation takes 42 min from the end of radionuclide production and from [ 11 C]carbon dioxide produces [N-methyl- 11 C]erythromycin A lactobionate in 4-12% radiochemical yield, corrected for radioactive decay. (author)

  1. Supramolecular structures in N-isonicotinoyl arylaldehydehydrazones: multiple hydrogen-bonding modes in series of geometric isomers.

    Science.gov (United States)

    Wardell, Solange M S V; de Souza, Marcus V N; Wardell, James L; Low, John N; Glidewell, Christopher

    2007-12-01

    Sixteen N-isonicotinoyl arylaldehydehydrazones, NC(5)H(4)CONHN=CHC(6)H(4)R, have been studied and the structures of 14 of them have been determined, including the unsubstituted parent compound with R = H, and the complete sets of 2-, 3- and 4-substituted geometric isomers for R = F, Br and OMe, and two of the three isomers for R = Cl and OEt. The 2-chloro and 3-chloro derivatives are isostructural with the corresponding bromo isomers, and all compounds contain trans amide groups apart from the isostructural pair where R = 2-Cl and 2-Br, which contain cis amide groups. The structures exhibit a wide range of direction-specific intermolecular interactions, including eight types of hydrogen bonds, N-H...N, N-H...O, O-H...O, O-H...N, C-H...N, C-H...O, C-H...pi(arene) and C-H...pi(pyridyl), as well as pi...pi stacking interactions. The structures exhibit a very broad range of combinations of these interactions: the resulting hydrogen-bonded supramolecular structures range from one-dimensional when R = 2-F, 2-OMe or 2-OEt, via two-dimensional when R = 4-F, 3-Cl, 3-Br, 4-OMe or 3-OEt, to three-dimensional when R = H, 3-F, 2-Cl, 2-Br, 4-Br or 3-OMe. Minor changes in either the identity of the substituent or its location can lead to substantial changes in the pattern of supramolecular aggregation, posing significant problems of predictability. The new structures are compared with the recently published structures of the isomeric series having R = NO(2), with several monosubstituted analogues containing 2-pyridyl or 3-pyridyl units rather than 4-pyridyl, and with a number of examples having two or three substituents in the aryl ring: some 30 structures in all are discussed.

  2. Synthesis and preclinical evaluation of carbon-11 labelled N-((5-(4-fluoro-2-[11C]methoxyphenyl)pyridin-3-yl)methyl)cyclopentanamine as a PET tracer for NR2B subunit-containing NMDA receptors

    International Nuclear Information System (INIS)

    Christiaans, Johannes A.M.; Klein, Pieter J.; Metaxas, Athanasios; Kooijman, Esther J.M.; Schuit, Robert C.; Leysen, Josée E.; Lammertsma, Adriaan A.; Berckel, Bart N.M. van; Windhorst, Albert D.

    2014-01-01

    Introduction: The N-methyl-D-Aspartate (NMDA) receptor plays an important role in learning and memory. Overactivation is thought to play an important role in neurodegenerative disorders such as Alzheimer's disease. Currently, it is not possible to assess N-methyl-D-aspartate receptor (NMDAr) bio-availability in vivo. The purpose of this study was to develop a positron emission tomography (PET) ligand for the NR2B binding site of the NMDA receptor. Methods: N-((5-(4-fluoro-2-methoxyphenyl)pyridin-3-yl)methyl)cyclopentanamine was radiolabelled with carbon-11 in the phenyl moiety. Biodistribution and blocking studies were carried out in anaesthetized mice and in non-anaesthetized rats. Results: N-((5-(4-fluoro-2-[ 11 C]methoxyphenyl)pyridin-3-yl)methyl)cyclopentanamine was prepared in 49 ± 3% (decay-corrected) yield, affording 4.1 ± 0.3 GBq of formulated product at the end of synthesis with a radiochemical purity of > 99% and with a specific activity of 78 ± 10 GBq/μmol. Conclusion: A new NR2B PET ligand was developed in high yield. [ 11 C]4 readily enters the brain and binds to the NR2B subunit-containing NMDAr in the rodent brain. High sigma-1 receptor binding may, however, limit its future application as a PET probe for imaging the NR2B subunit-containing NMDAr. Anaesthesia has an effect on NMDAr function and therefore can complicate interpretation of preclinical in vivo results. In addition, effects of endogenous compounds cannot be excluded. Despite these potential limitations, further studies are warranted to investigate the values of [ 11 C]4 as an NR2B PET ligand

  3. Supramolecular packing and polymorph screening of N-isonicotinoyl arylketone hydrazones with phenol and amino modifications

    Science.gov (United States)

    Hean, Duane; Michael, Joseph P.; Lemmerer, Andreas

    2018-04-01

    Thirteen structural variants based on the (E)-N‧-(1-arylethylidene)pyridohydrazide template were prepared, investigated and screened for possible polymorphic behaviour. Four variants showed from Differential Scanning Calorimetry Scans thermal events indicative of new solid-state phases. The thirteen variants included substituents R = sbnd OH or sbnd NH2 placed at ortho, meta and para positions on the phenyl ring; and shifting the pyridyl nitrogen between positions 4-, 3- and 2-. The crystal structures of twelve of the compounds were determined to explore their supramolecular structures. The outcomes of these modifications demonstrated that the pyridyl nitrogen at the 2- position is 'locked' by forming a hydrogen bond with the amide hydrogen; while placing the pyridyl nitrogen at positions 3- and 4- offers a greater opportunity for hydrogen bonding with neighbouring molecules. Such interactions include Osbnd H⋯N, Nsbnd H⋯N, Osbnd H⋯O, Nsbnd H⋯O, Nsbnd H⋯π, π⋯π stacking, as well as other weaker interactions such as Csbnd H⋯N, Csbnd H⋯O, Csbnd H⋯N(pyridyl). When OH or NH2 donors are placed in the ortho position, an intramolecular hydrogen bond is formed between the acceptor hydrazone nitrogen and the respective donor. The meta- and para-positioned donors form an unpredictable array of supramolecular structures by forming hydrogen-bonded chains with the pyridyl nitrogen and carbonyl acceptors respectively. In addition to the intramolecular and chain hydrogen bond formation demonstrated throughout the crystal structures under investigation, larger order hydrogen-bonded rings were also observed in some of the supramolecular aggregations. The extent of the hydrogen-bonded ring formations range from two to six molecular participants depending on the specific crystal structure.

  4. Polymethylated [Fe(η6-arene)2]2+ dications: methyl-group rearrangements and application of the EINS mechanism.

    Science.gov (United States)

    Štíbr, Bohumil; Bakardjiev, Mario; Hájková, Zuzana; Holub, Josef; Padělková, Zdenka; Růžička, Aleš; Kennedy, John D

    2011-06-14

    Reactions between the methylated arenes ArMe(n) [where ArMe(n) = C(6)Me(n)H((6-n)), and n = 1-6] and FeCl(2) in heptane at 90 °C in the presence of anhydrous AlCl(3) give, for the arenes with n = 1-5, extensive isomerisations and disproportionations involving the methyl groups on the arene rings, and the formation of mixtures of [Fe(ArMe(n))(2)](2+) dications that defy separation into pure species. GC-MS studies of AlCl(3)/mesitylene and AlCl(3)/durene reactions in the absence of FeCl(2) (90 °C, 2 h) allow quantitative assessments of the rearrangements, and the EINS mechanism (electrophile-induced nucleophilic substitution) is applied to rationalise the phenomena. By contrast, ArMe(n) / FeCl(2) /AlCl(3) reactions in heptane for 24-36 h at room-temperature proceed with no rearrangements, allowing the synthesis of the complete series of pure [Fe(ArMen)](2+) cations in yields of 48-71%. The pure compounds are characterised by (1)H NMR spectroscopy and electrospray-ionization mass-spectrometry (ESI-MS), and the structures of [Fe(m-xylene)(2)][PF(6)](2) and [Fe(durene)(2)][PF(6)](2) are established by single-crystal X-ray diffraction analyses.

  5. Crystal structure of dichlorido{2-methyl-2-[(pyridin-2-ylmethylamino]propan-1-ol-κ3N,N′,O}copper(II from synchrotron data

    Directory of Open Access Journals (Sweden)

    Jong Won Shin

    2016-10-01

    Full Text Available The title compound, [CuCl2(C10H16N2O], has been synthesized and characterized by synchrotron single-crystal X-ray diffraction and FT–IR spectroscopy. The 2-methyl-2-[(pyridin-2-ylmethylamino]propan-1-ol (mpmapOH ligand, including pyridine, amine and hydroxy groups, was synthesized by the reaction of 2-amino-2-methylpropan-1-ol with pyridine-2-carbaldehyde and was characterized by NMR spectroscopy. In its CuII complex, the metal ion has a distorted square-pyramidal coordination geometry with two N and one O atom of the mpmapOH ligand and one chloride anion in the equatorial plane, and the second chloride in an axial position. The bond lengths involving the CuII ion range from 1.9881 (10 to 2.0409 (9 for the Cu—N and Cu—O bonds, and from 2.2448 (5 to 2.5014 (6 Å for the equatorial and axial Cu—Cl bonds, respectively. Intermolecular hydrogen bonds (N—H...Cl and O—H...Cl and face-to-face π–π interactions stabilize the molecular structure and give rise to a two-dimensional supramolecular structure extending parallel to (101.

  6. Neutral coordination polymers based on a metal-mono(dithiolene) complex: synthesis, crystal structure and supramolecular chemistry of [Zn(dmit)(4,4'-bpy)]n, [Zn(dmit)(4,4'-bpe)]n and [Zn(dmit)(bix)]n (4,4'-bpy = 4,4'-bipyridine, 4,4'-bpe = trans-1,2-bis(4-pyridyl)ethene, bix = 1,4-bis(imidazole-1-ylmethyl)-benzene.

    Science.gov (United States)

    Madhu, Vedichi; Das, Samar K

    2011-12-28

    This article describes a unique synthetic route that enables a neutral mono(dithiolene)metal unit, {Zn(dmit)}, to link with three different organic molecules, resulting in the isolation of a new class of neutral coordination polymers. The species {Zn(dmit)} coordinates with 4,4'-bipyridine (4,4'-bpy), trans-1,2-bis(4-pyridyl)ethene (4,4'-bpe) and 1,4-bis(imidazole-1-ylmethyl)-benzene (bix) as linkers giving rise to the formation of coordination polymers [Zn(dmit)(4,4'-bpy)](n) (1), [Zn(dmit)(4,4'-bpe)](n) (2) and [Zn(dmit)(bix)](n) (3) respectively. Compounds 1-3 were characterized by elemental analyses, IR, diffuse reflectance and single crystal X-ray diffraction studies. Compounds 1 and 3 crystallize in the monoclinic space group P2(1)/n, whereby compound 2 crystallizes in triclinic space group P1[combining macron]. In the present study, we chose three linkers 4,4'-bpy, 4,4'-bpe and bix (see , respectively, for their structural drawings), that differ in terms of their molecular dimensions. The crystal structures of compounds 1-3 are described here in terms of their supramolecular diversities that include π-π interactions, not only among aromatic stacking (compounds 1 and 3), but also between an aromatic ring and an ethylenic double bond (compound 2). The electronic absorption spectroscopy of compounds 1-3 support these intermolecular π-π interactions. This journal is © The Royal Society of Chemistry 2011

  7. Determination and modeling of binary and ternary solid-liquid phase equilibrium for the systems formed by 1,8-dinitronaphthalene and 1,5-dinitronaphthalene and N-methyl-2-pyrrolidone

    International Nuclear Information System (INIS)

    Xie, Yong; Du, Cunbin; Cong, Yang; Wang, Jian; Han, Shuo; Zhao, Hongkun

    2016-01-01

    Highlights: • SLE formed by 1,5 and/or 1,8-dinitronaphthalene and NMP was determined. • The binary and ternary phase diagrams were constructed. • The phase diagrams were correlated and calculated using thermodynamic models. - Abstract: The solubility of 1,8-dinitronaphthalene and 1,5-dinitronaphthalene in N-methyl-2-pyrrolidone at (293.15–343.15) K and the mutual solubility of the ternary 1,5-dinitronaphthalene + 1,8-dinitronaphthalene + N-methyl-2-pyrrolidone mixture at (313.15, 328.15 and 343.15) K were determined experimentally using the isothermal saturation method under atmospheric pressure (101.2 kPa). The solubility of 1,8-dinitronaphthalene in N-methyl-2-pyrrolidone is larger than that of 1,5-dinitronaphthalene. Three isothermal ternary phase diagrams were built according to the measured mutual solubility data. In each ternary phase diagram, there were one co-saturated point, two boundary curves, and three crystalline regions. Two pure solids (pure 1,8-dinitronaphthalene and pure 1,5-dinitronaphthalene) were formed in the ternary system at a given temperature, which were identified by Schreinemaker’s method of wet residue and powder X-ray diffraction (PXRD) pattern. The crystallization region of 1,8-dinitronaphthalene was smaller than that of 1,5-dinitronaphthalene at each temperature. The modified Apelblat equation, λh equation, NRTL model and Wilson model were used to correlate the solubility of 1,8-dinitronaphthalene and 1,5-dinitronaphthalene in N-methyl-2-pyrrolidone; and the NRTL and Wilson models were employed to correlate and calculate the mutual solubility for the ternary 1,5-dinitronaphthalene + 1,8-dinitronaphthalene + N-methyl-2-pyrrolidone system. The largest value of root-mean-square deviation (RMSD) was 20.34 × 10 −4 for the binary systems; and 7.38 × 10 −3 for ternary system. The calculated results via these models are all acceptable for the binary and ternary solid-liquid phase equilibrium.

  8. Studies on the interactions of 5-R-3-(2-pyridyl)-1,2,4-triazines with arynes: inverse demand aza-Diels-Alder reaction versus aryne-mediated domino process.

    Science.gov (United States)

    Kopchuk, Dmitry S; Nikonov, Igor L; Khasanov, Albert F; Giri, Kousik; Santra, Sougata; Kovalev, Igor S; Nosova, Emiliya V; Gundala, Sravya; Venkatapuram, Padmavathi; Zyryanov, Grigory V; Majee, Adinath; Chupakhin, Oleg N

    2018-05-02

    The interactions between substituted 5-R-3-(pyridyl-2)-1,2,4-triazines with in situ generated substituted aryne intermediates have been studied. The reaction afforded either inverse demand (ID) aza-Diels-Alder products or 1,2,4-triazine ring rearrangement (domino) products as major ones depending on the nature of both the substituents at the C5 position of the 1,2,4-triazine core or in the aryne moiety. The structures of the key products were confirmed based on X-ray data. Based on the density functional theoretical (DFT) studies of the Diels-Alder transition state geometries, the influence of the nature of arynes on the direction of the 1,2,4-triazine transformation has been proposed.

  9. 2-Aminobenzoic acid–4,4′-bipyridine (2/1

    Directory of Open Access Journals (Sweden)

    Hadi D. Arman

    2013-09-01

    Full Text Available The asymmetric unit of title co-crystal, C10H8N2·2C7H7NO2, comprises a centrosymmetric 4,4′-bipyridine molecule, and a 2-aminobenzoic acid molecule in a general position. The latter is effectively planar [C—C—C—O torsion angle = 5.0 (3°] owing to an intramolecular N—H...O(carbonyl hydrogen bond. Three-molecule aggregates are formed via O—H...N(pyridyl hydrogen bonds and these are connected into supramolecular layers in the bc plane by N—H...O(carbonyl hydrogen bonds and π–π interactions between pyridyl and benzene rings [inter-centroid distance = 3.634 (2 Å]. Layers are connected along the a axis by weak π–π interactions between benzene rings [3.964 (2 Å].

  10. Tetra-2,3-pyrazinoporphyrazines with externally appended pyridine rings. 15. Effects of the pyridyl substituents and fused exocyclic rings on the UV-visible spectroscopic properties of Mg(II)-porphyrazines: a combined experimental and DFT/TDDFT study.

    Science.gov (United States)

    Donzello, Maria Pia; De Mori, Giorgia; Viola, Elisa; Ercolani, Claudio; Ricciardi, Giampaolo; Rosa, Angela

    2014-08-04

    Two new Mg(II) porphyrazine macrocycles, the octakis(2-pyridyl)porphyrazinato-magnesium(II), [Py8PzMg(H2O)], and the tetrakis-[6,7-di(2-pyridyl)quinoxalino]porphyrazinato-magnesium(II), [Py8QxPzMg(H2O)], were prepared by Mg-template macrocyclization processes, and their general physicochemical properties were examined. The previously reported porphyrazine analog, the tetrakis-2,3-[5,6-di(2-pyridyl)-pyrazino]porphyrazinato-magnesium(II), [Py8PyzPzMg(H2O)], has been also considered in the present work. The UV-visible solution spectra in nonaqueous solvents of this triad of externally octapyridinated Mg(II) complexes exhibit the usual profile observed for phthalocyanine and porphyrazine macrocycles, with intense absorptions in the Soret (300-450 nm) and Q band (600-800 nm) regions. It is observed that the Q band maximum sensibly shifts toward the red with peak values at 635 → 658 → 759 nm along the series [Py8PzMg(H2O)], [Py8PyzPzMg(H2O)], and [Py8QxPzMg(H2O)], as the extension of the macrocycle π-system increases. TDDFT calculations of the electronic absorption spectra were performed for the related water-free model compounds [Py8PzMg], [Py8PyzPzMg], and [Py8QxPzMg] to provide an interpretation of the UV-visible spectral changes occurring upon introduction of the pyrazine and quinoxaline rings at the periphery of the Pz macrocycle. To discriminate the electronic effects of the fused exocyclic rings from those of the appended 2-pyridyl rings, the UV-visible spectra of [PzMg] and [PyzPzMg] were also theoretically investigated. The theoretical results prove to agree very well with the experimental data, providing an accurate description of the UV-visible spectra. The observed spectral changes are interpreted on the basis of the electronic structure changes occurring along the series.

  11. Synthesis, Characterization and Application of A Novel Carbon Bridged Half-metallocene Chromium Catalyst for Methyl Methacrylate Polymerization

    Institute of Scientific and Technical Information of China (English)

    CHENG Zhengzai; GONG Kai; WANG Yang; ZHOU Xue; ZHANG Weixing; LI Yin; SUN Junquan; LI Wenbing

    2014-01-01

    A new carbon bridged cyclopentadienyl chromium complex of the type [(C5H4)C(CH3)2 CH2(C5H4N)]CrCl2 was prepared by treatment of CrCl3•(THF)3 in THF solution with the lithium salt of ligand containing cyclopentadienyl and pyridyl groups. The chromium complex was characterized by 1H NMR and elemental analysis(EA), and the crystal structure was determined by X-ray diffraction analysis. Activated by Al(i-Bu)3, the chromium complex displayed a very high activity for methyl methacrylate (MMA) polymerization. After 24 hours,more than 95.5%MMA was converted to polymethyl methacrylate (PMMA) with a viscosity average molecular weight (Wη) of 416000 g•mol-1 at 60℃for MMA/Al(i-Bu)3/chromium catalyst molar ratio of up to 2000:20:1. Effects of temperature, molar ratios of MMA/catalyst and catalyst/cocatalyst on the polymerization have been studied. The high conversion of MMA and high molecular weight of PMMA with narrow molecular weight distribution is caused by the unique stable active site formed by the new chromium complex and aluminum cocatalyst.

  12. Control of box C/D snoRNP assembly by N6-methylation of adenine.

    Science.gov (United States)

    Huang, Lin; Ashraf, Saira; Wang, Jia; Lilley, David Mj

    2017-09-01

    N 6 -methyladenine is the most widespread mRNA modification. A subset of human box C/D snoRNA species have target GAC sequences that lead to formation of N 6 -methyladenine at a key trans Hoogsteen-sugar A·G base pair, of which half are methylated in vivo The GAC target is conserved only in those that are methylated. Methylation prevents binding of the 15.5-kDa protein and the induced folding of the RNA Thus, the assembly of the box C/D snoRNP could in principle be regulated by RNA methylation at its critical first stage. Crystallography reveals that N 6 -methylation of adenine prevents the formation of trans Hoogsteen-sugar A·G base pairs, explaining why the box C/D RNA cannot adopt its kinked conformation. More generally, our data indicate that sheared A·G base pairs (but not Watson-Crick base pairs) are more susceptible to disruption by N 6 mA methylation and are therefore possible regulatory sites. The human signal recognition particle RNA and many related Alu retrotransposon RNA species are also methylated at N6 of an adenine that forms a sheared base pair with guanine and mediates a key tertiary interaction. © 2017 The Authors. Published under the terms of the CC BY 4.0 license.

  13. Unsymmetrical dizinc complexes as models for the active sites of phosphohydrolases.

    Science.gov (United States)

    Jarenmark, Martin; Csapó, Edit; Singh, Jyoti; Wöckel, Simone; Farkas, Etelka; Meyer, Franc; Haukka, Matti; Nordlander, Ebbe

    2010-09-21

    The unsymmetrical dinucleating ligand 2-(N-isopropyl-N-((2-pyridyl)methyl)aminomethyl)-6-(N-(carboxylmethyl)-N-((2-pyridyl)methyl)aminomethyl)-4-methylphenol (IPCPMP or L) has been synthesized to model the active site environment of dinuclear metallohydrolases. It has been isolated as the hexafluorophosphate salt H(4)IPCPMP(PF(6))(2) x 2 H(2)O (H(4)L), which has been structurally characterized, and has been used to form two different Zn(II) complexes, [{Zn(2)(IPCPMP)(OAc)}(2)][PF(6)](2) (2) and [{Zn(2)(IPCPMP)(Piv)}(2)][PF(6)](2) (3) (OAc = acetate; Piv = pivalate). The crystal structures of and show that they consist of tetranuclear complexes with very similar structures. Infrared spectroscopy and mass spectrometry indicate that the tetranuclear complexes dissociate into dinuclear complexes in solution. Potentiometric studies of the Zn(II):IPCPMP system in aqueous solution reveal that a mononuclear complex is surprisingly stable at low pH, even at a 2:1 Zn(II):L ratio, but a dinuclear complex dominates at high pH and transforms into a dihydroxido complex by a cooperative deprotonation of two, probably terminally coordinated, water molecules. A kinetic investigation indicates that one of these hydroxides is the active nucleophile in the hydrolysis of bis(2,4-dinitrophenyl)phosphate (BDNPP) enhanced by complex 2, and mechanistic proposals are presented for this reaction as well as the previously reported transesterification of 2-hydroxypropyl p-nitrophenyl phosphate (HPNP) promoted by Zn(II) complexes of IPCPMP.

  14. Antimutagenic components in Glycyrrhiza against N-methyl-N-nitrosourea in the Ames assay.

    Science.gov (United States)

    Inami, Keiko; Mine, Yusuke; Kojo, Yukiko; Tanaka, Satomi; Ishikawa, Satoko; Mochizuki, Masataka

    2017-03-01

    Antimutagenesis against N-nitroso compounds contribute to prevention of human cancer. We have found that Glycyrrhiza aspera ethanolic extract exhibits antimutagenic activity against N-methyl-N-nitrosourea (MNU) using the Ames assay with Salmonella typhimurium TA1535. In the present study, eight purified components from Glycyrrhiza, namely glabridin, glycyrrhetinic acid, glycyrrhizin, licochalcone A, licoricesaponin H2, licoricesaponin G2, liquiritigenin and liquiritin were evaluated for their antimutagenicity against MNU in the Ames assay with S. typhimurium TA1535. Glycyrrhetinic acid, glycyrrhizin, licoricesaponin G2, licoricesaponin H2 and liquiritin did not show the antimutagenicity against MNU in S. typhimurium TA1535. Glabridin, licochalcone A and liquiritigenin reduced revertant colonies derived from MNU in S. typhimurium TA1535 without showing cytotoxic effects, indicating that these compounds possess antimutagenic activity against MNU. The inhibitory activity of glabridin and licochalcone A was more effective than that of liquiritigenin. Thus, Glycyrrhiza contains antimutagenic components against DNA alkylating, direct-acting carcinogens.

  15. Differential SLC1A2 Promoter Methylation in Bipolar Disorder With or Without Addiction

    Directory of Open Access Journals (Sweden)

    Yun-Fang Jia

    2017-07-01

    Full Text Available While downregulation of excitatory amino acid transporter 2 (EAAT2, the main transporter removing glutamate from the synapse, has been recognized in bipolar disorder (BD, the underlying mechanisms of downregulation have not been elucidated. BD is influenced by environmental factors, which may, via epigenetic modulation of gene expression, differentially affect illness presentation. This study thus focused on epigenetic DNA methylation regulation of SLC1A2, encoding for EAAT2, in BD with variable environmental influences of addiction. High resolution melting PCR (HRM-PCR and thymine–adenine (TA cloning with sequence analysis were conducted to examine methylation of the promoter region of the SLC1A2. DNA was isolated from blood samples drawn from BD patients (N = 150 with or without addiction to alcohol, nicotine, or food, defined as binge eating, and matched controls (N = 32. In comparison to controls, the SLC1A2 promoter region was hypermethylated in BD without addiction but was hypomethylated in BD with addiction. After adjusting for age and sex, the association of methylation levels with nicotine addiction (p = 0.0009 and binge eating (p = 0.0002 remained significant. Consistent with HRM-PCR, direct sequencing revealed increased methylation in CpG site 6 in BD, but decreased methylation in three CpG sites (6, 48, 156 in BD with alcohol and nicotine addictions. These results suggest that individual point methylation within the SLC1A2 promoter region may be modified by exogenous addiction and may have a potential for developing clinically valuable epigenetic biomarkers for BD diagnosis and monitoring.

  16. catena-Poly[[aquabis[N-(pyridin-3-ylisonicotinamide-κN1]copper(II]-μ-fumarato-κ2O1:O4

    Directory of Open Access Journals (Sweden)

    Sultan H. Qiblawi

    2012-12-01

    Full Text Available In the title compound, [Cu(C4H2O4(C11H9N3O2(H2O]n, CuII ions on crystallographic twofold rotation axes are coordinated in a square pyramidal environment by two trans O atoms belonging to two monodentate fumarate anions, two trans isonicotinamide pyridyl N-donor atoms from monodentate, pendant 3-pyridylisonicotinamide (3-pina ligands, and one apical aqua ligand, also sited on the crystallographic twofold rotation axis. The exobidentate fumarate ligands form [Cu(fumarate(3-pina2(H2O]n coordination polymer chains that are arranged parallel to [001]. In the crystal, these polymeric chains are anchored into supramolecular layers parallel to (100 by O—H...O hydrogen bonds between aqua ligands and unligating fumarate O atoms, and N—H...O(=C hydrogen bonds between 3-pina ligands. In turn, the layers aggregate by weak C—H...N and C—H...O hydrogen bonds, affording a three-dimensional network.

  17. Chichibabin-type direct alkylation of pyridyl alcohols with alkyl lithium reagents.

    Science.gov (United States)

    Jeffrey, Jenna L; Sarpong, Richmond

    2012-11-02

    Direct C(6) alkylation of pyridyl alcohols can be achieved following an initial deprotonation of the hydroxy group. This transformation, which is believed to occur by a Chichibabin-type alkylation, avoids lateral deprotonation prior to pyridine ring alkylation and gives increased regioselectivity for C(6) over C(4) alkylation.

  18. A fast response cadmium-selective polymeric membrane electrode based on N,N'-(4-methyl-1,2-phenylene)diquinoline-2-carboxamide as a new neutral carrier

    Energy Technology Data Exchange (ETDEWEB)

    Rezaei, B. [Department of Chemistry, Isfahan University of Technology, Isfahan 84156-84111 (Iran, Islamic Republic of)], E-mail: rezaei@cc.iut.ac.ir; Meghdadi, S.; Zarandi, R. Fazel [Department of Chemistry, Isfahan University of Technology, Isfahan 84156-84111 (Iran, Islamic Republic of)

    2008-05-01

    A new polyvinylchloride membrane sensor for Cd{sup 2+} ions based on N,N'-(4-methyl-1,2-phenylene)diquinoline-2-carboxamide (Mebqb) as a new and excellent neutral ionophore has been prepared. The sensor shows a Nernestian response for cadmium ions over a wide concentration range (1.0 x 10{sup -6} to 1.0 x 10{sup -1} M) with the determination coefficient of 0.9964 and slope of 29.9 {+-} 0.5 mV decade{sup -1}. The limit of detection is 8 x 10{sup -7} M. It has a fast response time of 3-8 s and can be used for at least 8 weeks without any divergence in potential. The electrode can be used in the pH range from 4.0 to 9.0. The proposed sensor shows a very good discriminating ability towards Cd{sup 2+} ion in comparison to some alkali, alkaline earth, transition and heavy metal ions. It was successfully applied for the direct determination of Cd{sup 2+}in standard and real sample solutions.

  19. Synthesis and biochemical evaluation of tritium-labeled 1-methyl-N-(8-methyl-8-azabicyclo[3.2.1]oct-3-yl)-1H-indazole-3-carboxa mide, a useful radioligand for 5HT3 receptors

    International Nuclear Information System (INIS)

    Robertson, D.W.; Bloomquist, W.; Cohen, M.L.; Reid, L.R.; Schenck, K.; Wong, D.T.

    1990-01-01

    The advent of potent, highly selective 5HT3 receptor antagonists has stimulated considerable interest in 5HT3 receptor mediated physiology and pharmacology. To permit detailed biochemical studies regarding interaction of the indazole class of serotonin (5HT) antagonists with 5HT3 receptors in multiple tissues, we synthesized 1-methyl-N-(8-methyl-8-azabicyclo[3.2.1]oct-3-yl)-1H-indazole- 3-carboxamide (LY278584, compound 9) in high specific activity, tritium-labeled form. This radioligand was selected as a synthetic target because of its potency as a 5HT3-receptor antagonist, its selectivity for this receptor viz a viz other 5HT-receptor subtypes, and the ability to readily incorporate three tritia via the indazole N-CH3 substituent. Alkylation of N-(8-methyl-8-azabicyclo[3.2.1]oct-3-yl)-1H-indazole-3-carboxamide (8) with sodium hydride and tritium-labeled iodomethane, followed by HPLC purification, resulted in [3H]-9 with a radiochemical purity of 99% and a specific activity of 80.5 Ci/mmol. This radioligand bound with high affinity to a single class of saturable recognition sites in membranes isolated from cerebral cortex of rat brain. The Kd was 0.69 nM and the Bmax was 16.9 fmol/mg of protein. The specific binding was excellent, and accounted for 83-93% of total binding at concentrations of 2 nM or less. The potencies of known 5HT3-receptor antagonists as inhibitors of [3H]-9 binding correlated well with their pharmacological receptor affinities as antagonists of 5HT-induced decreases in heart rate and contraction of guinea pig ileum, suggesting the central recognition site for this radioligand may be extremely similar to or identical with peripheral 5HT3 receptors

  20. Synthesis and characterization of n-alkylamino derivatives of vitamin K3: Molecular structure of 2-propylamino-3-methyl-1,4-naphthoquinone and antibacterial activities

    Science.gov (United States)

    Chadar, Dattatray; Camilles, Maria; Patil, Rishikesh; Khan, Ayesha; Weyhermüller, Thomas; Salunke-Gawali, Sunita

    2015-04-01

    We would like to introduce eight analogues of n-alkylamino derivatives of vitamin K3 (2-methyl-1,4-naphthoquinone) viz, 2-(n-alkylamino)-3-methyl-1,4-naphthoquinone (where n-alkyl is methyl; LM-1, ethyl; LM-2, propyl; LM-3, butyl; LM-4, pentyl; LM-5, hexyl; LM-6, heptyl; LM-7, octyl; LM-8). All the above analogues have been successfully synthesized from vitamin K3 and characterized using different analytical techniques. Furthermore, in order to understand the mechanistic aspects of formation of LM-1 to LM-8 compounds, we could propose the mechanism. The FT-IR analysis of LM-1 to LM-8 indicate the presence of characteristic band of Nsbnd H group ∼3287-3364 cm-1, the variation was attributed to extensive intramolecular hydrogen bonding interaction. The molecular structure of LM-3 compound has been confirmed by single crystal X-ray diffraction analysis. LM-3 compound crystallises in triclinic space group P1. There were four independent molecules in asymmetric unit cell and their molecular interactions observed via Nsbnd H⋯O, Csbnd H⋯O and π-π stacking of quinonoid rings. Pharmacological potential of all compounds has been evaluated in terms of their antibacterial activities against Pseudomonas aeruginosa and Staphylococcus aureus. All the compounds were active against both the strains while LM-2 was found to be more effective with a minimum inhibition concentration of 0.3125 μg/mL and 0.156 μg/mL respectively.

  1. Fatty acid methyl ester from Neurospora intermedia N-1 isolated from Indonesian red peanut cake (oncom merah).

    Science.gov (United States)

    Priatni, S; Hartati, S; Dewi, P; Kardono, L B S; Singgih, M; Gusdinar, T

    2010-08-01

    The objective of this study was to identify the Fatty Acid Methyl Ester (FAME) from Neurospora intermedia N-1 that isolated from Indonesian red peanut cake (oncom). FAME profiles have been used as biochemical characters to study many different groups of organisms, such as bacteria and yeasts. FAME from N. intermedia N-1 was obtained by some stages of extraction the orange spores and fractination using a chromatotron. The pure compound (1) was characterized by 500 mHz NMR (1H and 13C), FTIR and LC-MS. Summarized data's of 1H and 13C NMR spectra of compound 1 contained 19 Carbon, 34 Hydrogen and 2 Oxygen (C19H34O2). The position of the double bonds at carbon number 8 and 12 were indicated in the HMBC spectrum (2D-NMR). LC-MS spectrum indicates molecular weight of the compound 1 as 294 which is visible by the presence of protonated molecular ion [M+H] at m/z 295. Methyl esters of long chain fatty acids was presented by a 3 band pattern of IR spectrum with bands near 1249, 1199 and 1172 cm(-1). We suggested that the structure of the pure compound 1 is methyl octadeca-8,12-dienoate. The presence methyl octadeca-8,12-dienoate in N. intermedia is the first report.

  2. Aberrant TET1 Methylation Closely Associated with CpG Island Methylator Phenotype in Colorectal Cancer.

    Science.gov (United States)

    Ichimura, Norihisa; Shinjo, Keiko; An, Byonggu; Shimizu, Yasuhiro; Yamao, Kenji; Ohka, Fumiharu; Katsushima, Keisuke; Hatanaka, Akira; Tojo, Masayuki; Yamamoto, Eiichiro; Suzuki, Hiromu; Ueda, Minoru; Kondo, Yutaka

    2015-08-01

    Inactivation of methylcytosine dioxygenase, ten-eleven translocation (TET) is known to be associated with aberrant DNA methylation in cancers. Tumors with a CpG island methylator phenotype (CIMP), a distinct subgroup with extensive DNA methylation, show characteristic features in the case of colorectal cancer. The relationship between TET inactivation and CIMP in colorectal cancers is not well understood. The expression level of TET family genes was compared between CIMP-positive (CIMP-P) and CIMP-negative (CIMP-N) colorectal cancers. Furthermore, DNA methylation profiling, including assessment of the TET1 gene, was assessed in colorectal cancers, as well as colon polyps. The TET1 was silenced by DNA methylation in a subset of colorectal cancers as well as cell lines, expression of which was reactivated by demethylating agent. TET1 methylation was more frequent in CIMP-P (23/55, 42%) than CIMP-N (2/113, 2%, P CIMP-P, 16/40, 40%; CIMP-N, 2/24, 8%; P = 0.002), suggesting that TET1 methylation is an early event in CIMP tumorigenesis. TET1 methylation was significantly associated with BRAF mutation but not with hMLH1 methylation in the CIMP-P colorectal cancers. Colorectal cancers with TET1 methylation have a significantly greater number of DNA methylated genes and less pathological metastasis compared to those without TET1 methylation (P = 0.007 and 0.045, respectively). Our data suggest that TET1 methylation may contribute to the establishment of a unique pathway in respect to CIMP-mediated tumorigenesis, which may be incidental to hMLH1 methylation. In addition, our findings provide evidence that TET1 methylation may be a good biomarker for the prediction of metastasis in colorectal cancer. ©2015 American Association for Cancer Research.

  3. Synthesis and Physical and Chemical Properties of Hypergolic Chemicals such as N,N,N-Trimethylhydrazinium and 1-Ethyl-4-Methyl-1,2,4-Triazolium Salts

    Directory of Open Access Journals (Sweden)

    Young-Seok Kim

    2015-12-01

    Full Text Available Hypergolic chemicals N,N,N-trimethylhydrazinium iodide, [TMH]+[I]−, and 1-ethyl-4-methyl-1,2,4-triazolium iodide, [EMT]+[I]− were firstly synthesized by nucleophilic substitution (SN2. The successful synthesis of hypergolic chemicals [TMH]+[I]− and [EMT]+[I]− was confirmed by IR and 1H-NMR spectroscopy and, GC-mass spectrometry. Subsequently the hypergolic chemicals [TMH]+[X]− (X = CN−, N3−, NO3−, NO2−, ClO4−, AlCl4− were prepared via an ion exchange reaction from [TMH]+[I]− and [EMT]+[I]−, respectively. After that, a mixture of hypergolic chemicals was prepared by dissolving the synthesized hypergolic chemicals in 2-hydroxyethylhydrazine (HOCH2CH2NHNH2. The physical and chemical properties of the mixture such as decomposition temperature (Td, density (d, viscosity (η, and decomposition energy (ΔHd was then evaluated to determine suitability for use as liquid rocket fuels. The ignition delay (ID time of the mixture of hypergolic chemicals with [TMH]+[N3]− and [TMH]+[CN]− using H2O2 as an oxidizer was determined as 55.6 ms and 97.4 ms; respectively. The ID time of the mixture of hypergolic chemicals with [EMT]+[N3]−; [EMT]+[CN]−; [EMT]+[AlCl4]−; and [EMT]+[I]− using H2O2 as an oxidizer was also determined as 18.0 ms; 32.6 ms; 27.6 ms; and 7.96 ms; respectively. The synthesized mixture of hypergolic chemicals could thus be used as a rocket propellant liquid fuel.

  4. Interaction between N-methyl-N'-nitro-N-nitrosoguanidine and ultraviolet irradiation on Bacillus subtilis

    International Nuclear Information System (INIS)

    Lotareva, O.V.

    1990-01-01

    The mutagenic interaction between ultraviolet-irradiation and the alkylating agent N-methyl-N'-nitro-N-nitrosoguanidine was studied in a repaid-competent and excision-deficient strains of Bacillus subtilis. Pre-exposure to low doses of MNNG with following treatment by low and intermediate doses of UV-light increase the resistance of Bac. subtilis to UV-radiation (antagonistic effect). Probably pre-exposition with MNNG leads to induction of enzymes reparation, UV-damages being controlled with adaptive respons genes

  5. Thiol-thione tautomeric analysis, spectroscopic (FT-IR, Laser-Raman, NMR and UV-vis) properties and DFT computations of 5-(3-pyridyl)-4H-1,2,4-triazole-3-thiol molecule.

    Science.gov (United States)

    Gökce, Halil; Öztürk, Nuri; Ceylan, Ümit; Alpaslan, Yelda Bingöl; Alpaslan, Gökhan

    2016-06-15

    In this study, the 5-(3-pyridyl)-4H-1,2,4-triazole-3-thiol molecule (C7H6N4S) molecule has been characterized by using FT-IR, Laser-Raman, NMR and UV-vis spectroscopies. Quantum chemical calculations have been performed to investigate the molecular structure (thione-thiol tautomerism), vibrational wavenumbers, electronic transition absorption wavelengths in DMSO solvent and vacuum, proton and carbon-13 NMR chemical shifts and HOMOs-LUMOs energies at DFT/B3LYP/6-311++G(d,p) level for all five tautomers of the title molecule. The obtained results show that the calculated vibrational wavenumbers, NMR chemical shifts and UV-vis wavelengths are in a good agreement with experimental data. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Structure of Pigment Yellow 181 dimethylsulfoxide N-methyl-2-pyrrolidone (1:1:1) solvate from XRPD plus DFT-D

    DEFF Research Database (Denmark)

    van de Streek, Jacco

    2015-01-01

    With only a 2.6 Å resolution laboratory powder diffraction pattern of the phase of Pigment Yellow 181 (P.Y. 181) available, crystal-structure solution and Rietveld refinement proved challenging; especially when the crystal structure was shown to be a triclinic dimethylsulfoxide N-methyl-2...... of commercial interest, additional experiments were not economically feasible and additional dispersion-corrected density functional theory (DFT-D) calculations were employed to confirm the correctness of the crystal structure. After the correctness of the structure had been ascertained, the bond lengths...

  7. trans-Diaquabis[2,5-bis(pyridin-2-yl-1,3,4-thiadiazole]cobalt(II bis(tetrafluoridoborate

    Directory of Open Access Journals (Sweden)

    Fouad Bentiss

    2011-07-01

    Full Text Available The bidentate 1,3,4-thiadiazole ligand substituted by two 2-pyridyl rings (denoted L has been found to produce the new monomeric title complex, [Co(C12H8N4S2(H2O2](BF42. The thiadiazole and pyridyl rings surrounding the Co atom are almost coplanar [dihedral angle = 4.35 (7°]. The mean plane defined by these heterocyclic moieties makes a dihedral angle of 18.72 (6° with the non-coordinated pyridyl ring. The Co2+ cation, located at a crystallographic center of symmetry, is bonded to two ligands and two water molecules in a trans configuration in an octahedral environment. The tetrafluoridoborate ions can be regarded as free anions in the crystal lattice. Nevertheless, they are involved in an infinite two-dimensional network along the [010] and [101] directions of O—H...F hydrogen bonds.

  8. Distribution and elimination of the glycosidase inhibitors 1-deoxymannojirimycin and N-methyl-1-deoxynojirimycin in the rat in vivo.

    Science.gov (United States)

    Faber, E D; Oosting, R; Neefjes, J J; Ploegh, H L; Meijer, D K

    1992-11-01

    We studied the pharmacokinetics of two synthetic derivatives of 1-deoxynojirimycin in the rat after intravenous administration. The mannosidase IA/B inhibitor 1-deoxymannojirimycin and the glucosidase inhibitor N-methyl-1-deoxynojirimycin exhibited minimal plasma protein binding and showed a rapid biphasic plasma disappearance, with an initial t1/2 of 3.0 and 4.5 min, respectively, and a terminal t1/2 of 51 and 32 min, respectively. For both compounds renal excretion is the major route of elimination. After 120 min, 52% of the dose of 1-deoxymannojirimycin and 80% of the dose of N-methyl-1-deoxymannojirimycin was recovered unchanged from the urine, whereas only 4.9 and 0.2%, respectively, of the dose was excreted in bile. Urinary clearance of 1-deoxymannojirimycin was similar to the glomerular filtration rate. In contrast, urinary clearance of N-methyl-1-deoxynojirimycin was two to three times higher than the glomerular filtration rate, indicating active tubular secretion. Ligation of the renal vessels decreased the total-body clearance of 1-deoxymannojirimycin and N-methyl-1-deoxynojirimycin 18- and 24-fold, respectively. Neither alkalinization of the urine by infusion of bicarbonate solutions nor forced diuresis altered the renal excretion rate of these compounds, implying the absence of tubular reabsorption. At 120 min, the amounts of 1-deoxymannojirimycin in liver and kidney were 2.1 and 1.1% of the dose, respectively, while small intestine, stomach, and heart contained only 0.9, 0.6 and 0.1%. Less than 1% of the dose of N-methyl-1-deoxynojirimycin was found in the collected organs 2 hr after injection.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Anti-leucine rich glioma inactivated 1 protein and anti-N-methyl-D-aspartate receptor encephalitis show distinct patterns of brain glucose metabolism in 18F-fluoro-2-deoxy-d-glucose positron emission tomography.

    Science.gov (United States)

    Wegner, Florian; Wilke, Florian; Raab, Peter; Tayeb, Said Ben; Boeck, Anna-Lena; Haense, Cathleen; Trebst, Corinna; Voss, Elke; Schrader, Christoph; Logemann, Frank; Ahrens, Jörg; Leffler, Andreas; Rodriguez-Raecke, Rea; Dengler, Reinhard; Geworski, Lilli; Bengel, Frank M; Berding, Georg; Stangel, Martin; Nabavi, Elham

    2014-06-20

    Pathogenic autoantibodies targeting the recently identified leucine rich glioma inactivated 1 protein and the subunit 1 of the N-methyl-D-aspartate receptor induce autoimmune encephalitis. A comparison of brain metabolic patterns in 18F-fluoro-2-deoxy-d-glucose positron emission tomography of anti-leucine rich glioma inactivated 1 protein and anti-N-methyl-D-aspartate receptor encephalitis patients has not been performed yet and shall be helpful in differentiating these two most common forms of autoimmune encephalitis. The brain 18F-fluoro-2-deoxy-d-glucose uptake from whole-body positron emission tomography of six anti-N-methyl-D-aspartate receptor encephalitis patients and four patients with anti-leucine rich glioma inactivated 1 protein encephalitis admitted to Hannover Medical School between 2008 and 2012 was retrospectively analyzed and compared to matched controls. Group analysis of anti-N-methyl-D-aspartate encephalitis patients demonstrated regionally limited hypermetabolism in frontotemporal areas contrasting an extensive hypometabolism in parietal lobes, whereas the anti-leucine rich glioma inactivated 1 protein syndrome was characterized by hypermetabolism in cerebellar, basal ganglia, occipital and precentral areas and minor frontomesial hypometabolism. This retrospective 18F-fluoro-2-deoxy-d-glucose positron emission tomography study provides novel evidence for distinct brain metabolic patterns in patients with anti-leucine rich glioma inactivated 1 protein and anti-N-methyl-D-aspartate receptor encephalitis.

  10. 4-[2-(4-cyanophenyl)ethenyl]-N-methylpyridinium tetraphenylborate.

    Science.gov (United States)

    Jin, Dan; Zhang, De Chun

    2005-11-01

    In the title compound, C(15)H(13)N(2)(+).C(24)H(20)B(-), the pyridyl ring of the cation makes a dihedral angle of 1.6 degrees with the benzene ring. Each is rotated in the same direction with respect to the central -C-CH=CH-C- linkage, by 3.8 and 5.3 degrees, respectively. The anions have a slightly distorted tetrahedral geometry. Molecular packing analysis was carried out using the packing energy portioning scheme in the program OPEC. Around each anion in the crystal structure there are eight anions, which interact with the central anion through C-H...pi interactions. The cations are hydrogen bonded in a head-to-tail fashion, forming chains along [101].

  11. Investigation of Complexation of Linear Poly(N-vinyl-2-pyrrolidone with Poly(methacrylic acid-co-methyl methacrylate Gel

    Directory of Open Access Journals (Sweden)

    Guoqin Liu

    2011-01-01

    Full Text Available The contraction of poly(methacrylic acid-co-methyl methacrylate (P(MAA-co-MMA gel induced by complexation with linear poly(N-vinyl-2-pyrrolidone (PVP is quite different from that of poly(acrylic acid (PAA or poly(methacrylic acid (PMAA gel. It was found that the concentration of PVP has a strong effect on the complexation with P(MAA-co-MMA gel. When PVP was introduced into the P(MAA-co-MMA network, its dynamic mechanic properties vary greatly between complexed and uncomplexed networks. It had the following results: (1 the higher modulus ratio; (2 a slight contraction of gel.

  12. N-(pyridylmethyl)azinium salts: precursors of pyridyl-stabilized azinium N-ylides

    OpenAIRE

    Agejas Chicharro, Francisco Javier; Cuadro Palacios, Ana María; Pastor Maeso, Manuel; Vaquero López, Juan José; García Navío, José Luis; Álvarez-Builla Gómez, Julio

    1995-01-01

    A series of new N-(pyridylmethyl)azinium salts have been synthesized from 2, 4, 6-triphenylpyrylium tetrafluoroborate. Generation of azinium N-ylides in the presence of base, has been proved by reactions with electrophiles, such as carbon disulphide, phenyl isothiocyanate and with acetylene dipolarophiles. Ministerio de Educación y Ciencia

  13. Nano-level determination of copper with atomic absorption spectrometry after pre-concentration on N,N-(4-methyl-1,2-phenylene)diquinoline-2-carboxamide-naphthalene

    Energy Technology Data Exchange (ETDEWEB)

    Rezaei, Behzad, E-mail: rezaei@cc.iut.ac.ir [Department of Chemistry, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Sadeghi, Elham; Meghdadi, Soraia [Department of Chemistry, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)

    2009-09-15

    A novel, simple, sensitive and effective method has been developed for selective extraction and pre-concentration of copper on N,N-(4-methyl-1,2-phenylene)diquinoline-2-carboxamide-naphthalene. After pre-concentration, copper was eluted from sorbent with hydrochloric acid, and then flame atomic absorption spectrometry (FAAS) was used for its determination. The effect of pH, sample flow rate and the volume and concentration of eluent on the recovery of the analyte was investigated and the optimum conditions were established. A pre-concentration factor of 400, and an adsorption capacity of 6.9 mg g{sup -1} of the solid-phase sorbent or 82.8 mg g{sup -1} of ligand was achieved using the optimum conditions. The calibration graph was linear in the range of 1.0-4000 ng mL{sup -1} with the detection limit of 1.0 ng mL{sup -1}. A R.S.D. value of 2.4% was obtained by this method for 400 ng mL{sup -1} of Cu{sup 2+} solution. This procedure has been successfully applied to separate and determine the ultra trace levels of copper in the environmental samples, free from the interference of some diverse ions.

  14. N6-adenosine methylation in MiRNAs.

    Directory of Open Access Journals (Sweden)

    Tea Berulava

    Full Text Available Methylation of N6-adenosine (m6A has been observed in many different classes of RNA, but its prevalence in microRNAs (miRNAs has not yet been studied. Here we show that a knockdown of the m6A demethylase FTO affects the steady-state levels of several miRNAs. Moreover, RNA immunoprecipitation with an anti-m6A-antibody followed by RNA-seq revealed that a significant fraction of miRNAs contains m6A. By motif searches we have discovered consensus sequences discriminating between methylated and unmethylated miRNAs. The epigenetic modification of an epigenetic modifier as described here adds a new layer to the complexity of the posttranscriptional regulation of gene expression.

  15. The kinetic analysis of the N-methylation of 4-phenylpyridine by nicotinamide N-methyltransferase: Evidence for a novel mechanism of substrate inhibition.

    Science.gov (United States)

    van Haren, Matthijs J; Thomas, Martin G; Sartini, Davide; Barlow, David J; Ramsden, David B; Emanuelli, Monica; Klamt, Fábio; Martin, Nathaniel I; Parsons, Richard B

    2018-03-13

    The N-methylation of 4-phenylpyridine produces the neurotoxin 1-methyl-4-phenylpyridinium ion (MPP+). We investigated the kinetics of 4-phenylpyridine N-methylation by nicotinamide N-methyltransferase (NNMT) and its effect upon 4-phenylpyridine toxicity in vitro. Human recombinant NNMT possessed 4-phenylpyridine N-methyltransferase activity, with a specific activity of 1.7 ± 0.03 nmol MPP+ produced/h/mg NNMT. Although the K m for 4-phenylpyridine was similar to that reported for nicotinamide, its k cat of 9.3 × 10 -5  ± 2 × 10 -5  s -1 and specificity constant, k cat /K m , of 0.8 ± 0.8 s -1  M -1 were less than 0.15% of the respective values for nicotinamide, demonstrating that 4-phenylpyridine is a poor substrate for NNMT. At low (N-methylation was competitively inhibited by dimethylsulphoxide, with a K i of 34 ± 8 mM. At high (>2.5 mM) substrate concentration, enzyme activity followed substrate inhibition kinetics, with a K i of 4 ± 1 mM. In silico molecular docking suggested that 4-phenylpyridine binds to the active site of NNMT in two non-redundant poses, one a substrate binding mode and the other an inhibitory mode. Finally, the expression of NNMT in the SH-SY5Y cell-line had no effect cell death, viability, ATP content or mitochondrial membrane potential. These data demonstrate that 4-phenylpyridine N-methylation by NNMT is unlikely to serve as a source of MPP+. The possibility for competitive inhibition by dimethylsulphoxide should be considered in NNMT-based drug discovery studies. The potential for 4-phenylpyridine to bind to the active site in two binding orientations using the same active site residues is a novel mechanism of substrate inhibition. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Symmetric dimeric bisbenzimidazoles DBP(n reduce methylation of RARB and PTEN while significantly increase methylation of rRNA genes in MCF-7 cancer cells.

    Directory of Open Access Journals (Sweden)

    Svetlana V Kostyuk

    Full Text Available Hypermethylation is observed in the promoter regions of suppressor genes in the tumor cancer cells. Reactivation of these genes by demethylation of their promoters is a prospective strategy of the anticancer therapy. Previous experiments have shown that symmetric dimeric bisbenzimidazoles DBP(n are able to block DNA methyltransferase activities. It was also found that DBP(n produces a moderate effect on the activation of total gene expression in HeLa-TI population containing epigenetically repressed avian sarcoma genome.It is shown that DBP(n are able to penetrate the cellular membranes and accumulate in breast carcinoma cell MCF-7, mainly in the mitochondria and in the nucleus, excluding the nucleolus. The DBP(n are non-toxic to the cells and have a weak overall demethylation effect on genomic DNA. DBP(n demethylate the promoter regions of the tumor suppressor genes PTEN and RARB. DBP(n promotes expression of the genes RARB, PTEN, CDKN2A, RUNX3, Apaf-1 and APC "silent" in the MCF-7 because of the hypermethylation of their promoter regions. Simultaneously with the demethylation of the DNA in the nucleus a significant increase in the methylation level of rRNA genes in the nucleolus was detected. Increased rDNA methylation correlated with a reduction of the rRNA amount in the cells by 20-30%. It is assumed that during DNA methyltransferase activity inhibition by the DBP(n in the nucleus, the enzyme is sequestered in the nucleolus and provides additional methylation of the rDNA that are not shielded by DBP(n.It is concluded that DBP (n are able to accumulate in the nucleus (excluding the nucleolus area and in the mitochondria of cancer cells, reducing mitochondrial potential. The DBP (n induce the demethylation of a cancer cell's genome, including the demethylation of the promoters of tumor suppressor genes. DBP (n significantly increase the methylation of ribosomal RNA genes in the nucleoli. Therefore the further study of these compounds is needed

  17. Acrylonitrile-methyl Methacrylate Copolymer Films Containing Microencapsulated n-Octadecane

    Institute of Scientific and Technical Information of China (English)

    LI Jun; HAN Na; ZHANG Xing-xiang

    2006-01-01

    Acrylonitrile-methyl methacrylate copolymer was synthesized in aqueous solution by Redox. The copolymer was mixed with 10 - 40 wt% of microencapsulated n-octadecane (MicroPCMs) in water. Copolymer films containing MicroPCMs were cast at room temperature in N, N-Dimethylformamide solution. The copolymer of acrylonitrile-methyl methacrylate and the copolymer films containing MicroPCMs were characterized by using Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Thermogravimetric Analyzer (TG), X-ray Diffrac tion (XRD) and Scanning Electron Microscopy (SEM), etc.The microcapsules in the films are evenly distributed in the copolymer matrix. The heat-absorbing temperatures and heat-evolving temperatures of the films are almost the same as that of the MicroPCMs, respectively, and fluctuate in a slight range. In addition, the enthalpy efficiency of MicroPCMs rises with the contents of MicroPCMs increasing.The crystallinity of the film increases with the contents of MicroPCMs increasing.

  18. DHA-rich n-3 fatty acid supplementation decreases DNA methylation in blood leukocytes: the OmegAD study.

    Science.gov (United States)

    Karimi, Mohsen; Vedin, Inger; Freund Levi, Yvonne; Basun, Hans; Faxén Irving, Gerd; Eriksdotter, Maria; Wahlund, Lars-Olof; Schultzberg, Marianne; Hjorth, Erik; Cederholm, Tommy; Palmblad, Jan

    2017-10-01

    Background: Dietary fish oils, rich in long-chain n-3 (ω-3) fatty acids (FAs) [e.g., docosahexaenoic acid (DHA, 22:6n-3) and eicosapentaenoic acid (EPA, 20:5n-3)], modulate inflammatory reactions through various mechanisms, including gene expression, which is measured as messenger RNA concentration. However, the effects of long-term treatment of humans with DHA and EPA on various epigenetic factors-such as DNA methylation, which controls messenger RNA generation-are poorly described. Objective: We wanted to determine the effects of 6 mo of dietary supplementation with an n-3 FA preparation rich in DHA on global DNA methylation of peripheral blood leukocytes (PBLs) and the relation to plasma EPA and DHA concentrations in Alzheimer disease (AD) patients. Design: In the present study, DNA methylation in four 5'-cytosine-phosphate-guanine-3' (CpG) sites of long interspersed nuclear element-1 repetitive sequences was assessed in a group of 63 patients (30 given the n-3 FA preparation and 33 given placebo) as an estimation of the global DNA methylation in blood cells. Patients originated from the randomized, double-blind, placebo-controlled OmegAD study, in which 174 AD patients received either 1.7 g DHA and 0.6 g EPA (the n-3 FA group) or placebo daily for 6 mo. Results: At 6 mo, the n-3 FA group displayed marked increases in DHA and EPA plasma concentrations (2.6- and 3.5-fold), as well as decreased methylation in 2 out of 4 CpG sites ( P DHA concentration, and were not related to apolipoprotein E-4 allele frequency. Conclusion: Supplementation with n-3 FA for 6 mo was associated with global DNA hypomethylation in PBLs. Our data may be of importance in measuring various effects of marine oils, including gene expression, in patients with AD and in other patients taking n-3 FA supplements. This trial was registered at clinicaltrials.gov as NCT00211159. © 2017 American Society for Nutrition.

  19. Methanogenesis from acetate by Methanosarcina barkeri: Catalysis of acetate formation from methyl iodide, CO/sub 2/, and H/sub 2/ by the enzyme system involved

    Energy Technology Data Exchange (ETDEWEB)

    Laufer, K; Eikmanns, B; Frimmer, U; Thauer, R K

    1987-04-01

    Cell suspensions of Methanosarcina barkeri grown on acetate catalyze the formation of methane and CO/sub 2/ from acetate as well as an isotopic exchange between the carboxyl group of acetate and CO/sub 2/. Here we report that these cells also mediate the synthesis of acetate from methyl iodide, CO/sub 2/, and reducing equivalents (H/sub 2/ or CO), the methyl group of acetate being derived from methyl iodide and the carboxyl group from CO/sub 2/. Methyl chloride and methyltosylate but not methanol can substitute for methyl iodide in this reaction. Acetate formation from methyl iodide, CO/sub 2/, and reducing equivalents is coupled with the phosphorylation of ADP. Evidence is presented that methyl iodide is incorporated into the methyl group of acetate via a methyl corrinoid intermediate (deduced from inhibition experiments with propyl iodide) and that CO/sub 2/ is assimilated into the carboxyl group via a C/sub 1/ intermediate which does not exchange with free formate or free CO. The effects of protonophores, of the proton-translocating ATPase inhibitor N,N'-dicyclohexylcarbodiimide, and of arsenate on acetate formation are interpreted to indicate that the reduction of CO/sub 2/ to the oxidation level of the carboxyl group of acetate requires the presence of an electrochemical proton potential and that acetyl-CoA or acetyl-phosphate rather than free acetate is the immediate product of the condensation reaction. These results are dicsussed with respect to the mechanism of methanogenesis from acetate.

  20. Fluorinated benzamide neuroleptics--III. Development of (S)-N-[(1-allyl-2-pyrrolidinyl)methyl]-5-(3-[{sup 18}F]fluoropropyl)-2,3- dimethoxybenzamide as an improved dopamine D-2 receptor tracer

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, Jogeshwar; Zhiying, Yang; Das, Malay K; Brown, Terry

    1995-04-01

    We have prepared five new analogs (n-propyl, iso-propyl, allyl, n-butyl, and iso-butyl) of the dopamine D-2 receptor antagonist, FPMB which result from modifications of the ethyl group at the pyrrolidine nitrogen in FPMB. As expected, all new derivatives showed higher apparent lipophilicity (log k{sub w}), with iso-butyl being the most lipophilic (log k{sub w} = 2.52), followed by the allyl derivative (log k{sub w} = 2.43). The allyl group showed the largest increase in affinity (from 0.26 nM for the ethyl substituent to 0.03 nM for the allyl substituent, almost 10-fold), followed by the n-propyl substituent which showed approximately five-fold better affinity than did the ethyl substituent. Radiosynthesis of S-N-[(1-allyl-2-pyrrolidinyl)methyl]-5-(3-[{sup 18}F]fluoropropyl)-2,3-dimethoxybenzamide ([{sup 18}F]fallypride) was carried out by nucleophilic substitution reaction of (S)-N-[(1-allyl-2-pyrrolidinyl)methyl]-5-(3-tosyloxypropyl)-2,3- dimethoxybenzamide with no carrier added {sup 18}F{sup -}. [{sup 18}F]Fallypride was obtained in approximately 20-40% yields (EOS/EOB, decay corrected) in specific activities of 900-1700 Ci/mmol after reverse phase HPLC purification in 60 min from EOB. High striatal uptake (upto 2.5% injected dose/g) of [{sup 18}F]fallypride in rats was observed with striatal/cerebellar ratios of 17, 42, 63 and 122 at 30, 60, 90 and 120 min post-injection, respectively. PET experiments with [{sup 18}F]fallypride in a cebus monkey showed a brain uptake of 0.10% injected dose/cc. In rhesus monkeys [{sup 18}F]fallypride showed rapid specific uptake in the striata (0.04-0.06% injected dose/cc) with striata/cerebellum ratios of approx. 3.0 at 14 min, 5.0 at 35 min and 8 at 70 min post-injection. Specifically bound [{sup 18}F]fallypride was displaced with haloperidol (1 mg/kg) with a half-life of 18 min in the rhesus monkey.

  1. Investigation of Complexation of Linear Poly(N-vinyl-2-pyrrolidone) with Poly(methacrylic acid-co-methyl methacrylate) Gel

    OpenAIRE

    Liu, Guoqin; Yan, Guojin; Zou, Wenjun; Li, Zhengxin

    2011-01-01

    The contraction of poly(methacrylic acid-co-methyl methacrylate) (P(MAA-co-MMA)) gel induced by complexation with linear poly(N-vinyl-2-pyrrolidone) (PVP) is quite different from that of poly(acrylic acid) (PAA) or poly(methacrylic acid) (PMAA) gel. It was found that the concentration of PVP has a strong effect on the complexation with P(MAA-co-MMA) gel. When PVP was introduced into the P(MAA-co-MMA) network, its dynamic mechanic properties vary greatly between complexed and uncomplexed netwo...

  2. Mechanism for the reaction of 2-naphthol with N-methyl-N-phenyl-hydrazine suggested by the density functional theory investigations.

    Science.gov (United States)

    Gao, Jie Ying; Zhang, Cheng Hua; Luo, Mei Ming; Kim, Chan Kyung; Chu, Wei; Xue, Ying

    2012-01-15

    For the first time the computed mechanisms for the novel reaction of 2-naphthol with N-methyl-N-phenylhydrazine, leading to 1-amino-2-naphthol (Tang et al., J Am Chem Soc 2008, 130, 5840), have been investigated using the density functional theory. Four distinct possible pathways were evaluated: two amination mechanisms with the attack of NH(2) group respectively at the α-position C1 and β-position C3 atoms of 2-naphthol (pathways 1 and 2) as well as two rearrangement processes with displacement of the phenolic hydroxyl group followed by the benzidine-like rearrangement at the α-position C1 and β-position C3 atoms of 2-naphthol, respectively (pathways 3 and 4). Solvent effect has been tested based on the optimized geometries of the stationary points in solution at the B3LYP/PCM/6-31+G(d,p) level of theory with an averaged dielectric constant of binary solvent. Single-point energies of the optimized structures have been calculated using three hybrid density functionals, B3LYP, MPW3LYP, and B3PW91 with the 6-311++G(3df,2p) basis set. Our computed results clearly manifest that pathway 1 (α-amination) has the highest possibility to occur, with the Gibbs free energies being lower by 6 to 20 kcal/mol compared with the other three pathways, which leads to 1-amino-2-naphthol and N-methylaniline as products. It is in excellent agreement with the experimental observation. Copyright © 2011 Wiley Periodicals, Inc.

  3. cyclo-Tetrakis(μ-3-acetyl-4-methyl-1H-pyrazole-5-carboxylato-κ4N2,O3:N1,O5tetrakis[aquacopper(II] tetradecahydrate

    Directory of Open Access Journals (Sweden)

    Sergey Malinkin

    2011-09-01

    Full Text Available The title compound, [Cu4(C7H6N2O34(H2O4]·14H2O, a tetranuclear [2 × 2] grid-type complex with S4 symmetry, contains four CuII atoms which are bridged by four pyrazolecarboxylate ligand anions and are additionally bonded to a water molecule. Each CuII atom is coordinated by two O atoms of the carboxylate and acetyl groups, two pyrazole N atoms of doubly deprotonated 3-acetyl-4-methyl-1H-pyrazole-5-carboxylic acid and one O atom of a water molecule. The geometry at each CuII atom is distorted square-pyramidal, with the two N and two O atoms in the equatorial plane and O atoms in the axial positions. O—H...O hydrogen-bonding interactions additionally stabilize the structure. One of the uncoordinated water molecules shows half-occupancy.

  4. Preparation of N(1-ethyl-2-pyrrolidyl-methyl)2-methoxy-4-iodo-125I-5-ethyl sulfonyl benzamide: a radioligand for the radioimmunoassay of sulpiride-related compounds

    International Nuclear Information System (INIS)

    Cardoso, M.T.; Pradelles, P.

    1982-01-01

    The preparation of 125 I labelling with a higher specific radioactivity of N(1-ethyl-2-pyrrolidyl-methyl)2-methoxy-5-ethyl sulfonyl benzamide, a potent biological analogue for sulpiride is described. The incorporation of iodine in the molecule was achieved by the substitution of aromatic amino groups via the diazo compound. Binding and immunological parameters of iodinated and tritiated tracers were compared. (author)

  5. Thermodynamic properties of poly(phenylene-pyridyl) dendrons of the second and the third generations

    International Nuclear Information System (INIS)

    Smirnova, Natalia N.; Samosudova, Yanina S.; Markin, Alexey V.; Serkova, Elena S.; Kuchkina, Nina V.; Shifrina, Zinaida B.

    2017-01-01

    Highlights: • We report thermodynamic properties for poly(phenylene-pyridyl) dendrons of the second and the third generations. • The thermodynamic quantities of devitrification and fusion have been determined. • Thermodynamic functions for the temperature range from T → 0 to 520 K for different physical states were calculated. • The dependences of thermodynamic properties of the dendrons on their composition and structure have been obtained. - Abstract: The temperature dependence of the heat capacity of poly(phenylene-pyridyl) dendrons of the second and the third generations have been measured by the method of adiabatic vacuum and differential scanning calorimetry over the range from 6 K to (500–520) K in the present research. Phase transformations have been detected and their thermodynamic characteristics have been estimated and analysed in the above temperature range. The standard thermodynamic functions, namely, the heat capacity C p 0 (T), enthalpy H°(T) − H°(0), entropy S°(T) − S°(0) and potential Φ m °, for the range from T → 0 K to (500–520) K and the standard entropy of formation of the dendrons in different physical states at T = 298.15 K have been calculated based on the experimental results. The thermodynamic characteristics of the samples under study and investigated earlier, poly(phenylene-pyridyl) dendrons decorated with dodecyl groups of the same generations have been compared and discussed.

  6. Acute Toxicity Associated With the Recreational Use of the Novel Psychoactive Benzofuran N-methyl-5-(2 aminopropyl)benzofuran.

    Science.gov (United States)

    Hofer, Katharina E; Faber, Katrin; Müller, Daniel M; Hauffe, Till; Wenger, Urs; Kupferschmidt, Hugo; Rauber-Lüthy, Christine

    2017-01-01

    N-methyl-5-(2 aminopropyl)benzofuran (5-MAPB) is a novel psychoactive benzofuran, created by N-methylation of 5-(2-aminopropyl)benzofuran (5-APB), which shares structural features with methylenedioxymethamphetamine (MDMA). To our knowledge, no case of 5-MAPB-related toxicity has been published in the scientific literature. We report a case of oral 5-MAPB exposure confirmed by liquid chromatography-tandem mass spectrometry in a 24-year-old previously healthy white man. Observed symptoms and signs such as paleness, cold and clammy skin, hypertension, elevated high-sensitive troponin T level, tachycardia, ECG change, diaphoresis, mild hyperthermia, mydriasis, tremor, hyperreflexia, clonus, agitation, disorientation, hallucinations, convulsions, reduced level of consciousness, and creatine kinase level elevation (305 IU/L) were compatible with undesired effects related to 5-APB or MDMA exposure. Signs and symptoms resolved substantially within 14 hours with aggressive symptomatic treatment, including sedation with benzodiazepines, external cooling, analgesia and sedation with fentanyl-propofol, and treatment with urapidil, an α-receptor-blocking agent. 5-MAPB showed first-order elimination kinetics with a half-life of 6.5 hours, comparable to the half-life of MDMA. According to the chemical structure, this case report, and users' Web reports, 5-MAPB appears to have an acute toxicity profile similar to that of 5-APB and MDMA, with marked vasoconstrictor effect. Copyright © 2016 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.

  7. Mobility and molecular ions of dimethyl methyl phosphonate, methyl salicylate and acetone

    Science.gov (United States)

    Nowak, D. M.

    1983-06-01

    The mobilities of positive and negative reactant ions are reported for (H2O)nH(+); (H2O)2O2 and (H2O)2CO3(-) ion clusters. The formation of positive DMMP monomer and dimer is reported, and equilbria molecular reactions are reported. Acetone is reported as forming a dimer at 81 ppb with a reduced mobility (K sub o) of 1.82, Methyl salicylate is shown to form a protonated and hydrated positive monomer. Mixtures of DMMP and methyl salicylate with acetone showed a substantial change in DMMP ion clustering and little or no change in the methyl salicylate mobility spectra. Negative ions were not observed for DMMP, methyl salicylate, acetone and the mixtures under the conditions reported.

  8. Dynamics and disorder of methyl group in the different phases of 2,6-dimethyl pyrazine, 4-methyl pyridine and 4-methyl pyridine N-oxide; Dynamique et desordre du groupe methyle dans les differentes phases de la 2,6-dimethyl pyrazine, 4-methyl pyridine et 4-methyl pyridine N-oxyde

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser Morris, E

    1997-12-22

    The thermal and mechanical properties of organic compounds are well known to be strongly correlated with the orientational freedom of its molecules or its molecular groups such as NH{sub 3}, CH{sub 3}, CH{sub 4}... For this reason, the study of the rotational behaviour of methyl groups in the solid state as a function of temperature is of great interest. With decreasing temperature, the rotations change from classical hoping to processes where quantum mechanical rotations become important. By quantum mechanical rotations, we mean the low-temperature counterpart, for with tunneling is the dominant mode of motion. However, the interpretation of tunnelling lines is critical when it is not straightforward to relate them to specific vibrational modes and particularly so when the molecule contains crystallographically inequivalent groups. The aim of this work is to interpret such spectra (obtained from inelastic neutron scattering) from structural data. The lack of structural knowledge at low temperatures, makes therefore a limited interpretation of the spectra obtained from polycrystalline samples. In a first step it is essential to solve crystalline structure of compounds by single crystal X-rays and neutron diffraction. Indeed X-ray diffraction is necessary to locate the skeleton (C, N, O and localised H atoms). Moreover neutron diffraction is the unique tool to precise the position of H atoms of methyl groups. The exam of the nuclear density of these protons the Fourier maps allows us to evaluate the crystal potential experienced by this rotor. Inelastic neutron scattering allows on single crystals allows the complete characterizations of quantum excitations (author) 75 refs.

  9. In vitro evaluation of N-methyl amide tripeptidomimetics as substrates for the human intestinal di-/tri-peptide transporter hPEPT1

    DEFF Research Database (Denmark)

    Andersen, Rikke; Nielsen, Carsten Uhd; Begtrup, Mikael

    2006-01-01

    application of N-methyl amide bioisosteres as peptide bond replacements in tripeptides in order to decrease degradation by peptidases and yet retain affinity for and transport via hPEPT1. Seven structurally diverse N-methyl amide tripeptidomimetics were selected based on a principal component analysis...... of structural properties of 6859 N-methyl amide tripeptidomimetics. In vitro extracellular degradation of the selected tripeptidomimetics as well as affinity for and transepithelial transport via hPEPT1 were investigated in Caco-2 cells. Decreased apparent degradation was observed for all tripeptidomimetics...... to be substrates for hPEPT1 than tripeptidomimetics with charged side chains. The results of the present study indicate that the N-methyl amide peptide bond replacement approach for increasing bioavailability of tripeptidomimetic drug candidates is not generally applicable to all tripeptides. Nevertheless...

  10. Methylation of food commodities during fumigation with methyl bromide

    International Nuclear Information System (INIS)

    Starratt, A.N.; Bond, E.J.

    1990-01-01

    Sites of methylation in several commodities (wheat, oatmeal, peanuts, almonds, apples, oranges, maize, alfalfa and potatoes) during fumigation with 14 C-methyl bromide were studied. Differences were observed in levels of the major volatiles: methanol, dimethyl sulphide and methyl mercaptan, products of O- and S-methylation, resulting from treatment of the fumigated materials with 1N sodium hydroxide. In studies of maize and wheat, histidine was the amino acid which underwent the highest level of N-methylation. (author). 24 refs, 3 tabs

  11. Crystal structure of 2-methyl-1H-imidazol-3-ium hydrogen oxalate dihydrate

    Directory of Open Access Journals (Sweden)

    Mouhamadou Birame Diop

    2016-08-01

    Full Text Available Single crystals of the title molecular salt, C4H7N2+·HC2O4−·2H2O, were isolated from the reaction of 2-methyl-1H-imidazole and oxalic acid in a 1:1 molar ratio in water. In the crystal, the cations and anions are positioned alternately along an infinite [010] ribbon and linked together through bifurcated N—H...(O,O hydrogen bonds. The water molecules of crystallization link the chains into (10-1 bilayers, with the methyl groups of the cations organized in an isotactic manner.

  12. Atypical presentation of anti-N-methyl-D-aspartate receptor encephalitis: two case reports.

    Science.gov (United States)

    Maggio, Maria Cristina; Mastrangelo, Greta; Skabar, Aldo; Ventura, Alessandro; Carrozzi, Marco; Santangelo, Giuseppe; Vanadia, Francesca; Corsello, Giovanni; Cimaz, Rolando

    2017-08-16

    Anti-N-methyl-D-aspartate receptor encephalitis is a rare autoimmune disease characterized by severe neurological and psychiatric symptoms and a difficult diagnosis. The disease is often secondary to a neoplastic lesion, seldom diagnosed years later. Psychiatric symptoms are prevalent in adults; neurologic symptoms are more evident in children, who typically present primarily with neurological symptoms. To the best of our knowledge, the association with juvenile idiopathic arthritis has not been described. We report the cases of two caucasian girls with an atypical presentation. The first patient was an 8-year-old girl with normal psychomotor development. Over a 4-month period she developed behavioral problems, speech impairment, and deterioration in academic skills. Within 8 months from the onset of symptoms, choreic movements gradually appeared. Hematological, neuroradiological, and neurophysiological examinations were negative; however, her symptoms worsened and treatment with prednisone was started. Although her choreic movements improved within 1 month, her neuropsychological and behavioral symptoms continued. Anti-N-methyl-D-aspartate receptor antibodies in cerebrospinal fluid and in blood were detected. Therapy with intravenously administered immunoglobulins was administered, without improvement of symptoms. After 2 months of steroid treatment, she suddenly started to pronounce some words with a progressive improvement in language and behavior. The second patient was a 14-year-old girl with classic anti-N-methyl-D-aspartate receptor encephalitis, treated successfully with intravenously administered immunoglobulins and methylprednisolone, followed by orally administered prednisone, who developed chronic arthritis of the hip. The arthritis was confirmed by magnetic resonance imaging and associated to antinuclear antigen antibody positivity. One year after the encephalitis presentation, an ovarian cystic mass was identified as a teratoma. The surgical resection

  13. Tweaking agonist efficacy at N-methyl-D-aspartate receptors by site-directed mutagenesis

    DEFF Research Database (Denmark)

    Hansen, Kasper B; Clausen, Rasmus P; Bjerrum, Esben J

    2005-01-01

    The structural basis for partial agonism at N-methyl-D-aspartate (NMDA) receptors is currently unresolved. We have characterized several partial agonists at the NR1/NR2B receptor and investigated the mechanisms underlying their reduced efficacy by introducing mutations in the glutamate binding site...

  14. N-methyl-D-aspartate promotes the survival of cerebellar granule cells: pharmacological characterization

    DEFF Research Database (Denmark)

    Balázs, R; Hack, N; Jørgensen, Ole Steen

    1989-01-01

    The survival of cerebellar granule cells in culture is promoted by chronic exposure to N-methyl-D-aspartate (NMDA). The effect is due to the stimulation of 'conventional' NMDA receptor-ionophore complex: it is concentration dependent, voltage dependent and blocked by the selective antagonists D-2...

  15. Response of clonogenic cells of mice solid tumour NKLy/LL to N-methyl-N-nitrosourea

    International Nuclear Information System (INIS)

    Chan Tik Kan; Afanas'ev, G.G.; Pelevina, I.I.

    1979-01-01

    By cloning in vitro the cells of NKLy/LL solid tumour of mice it has been shown that the curve of clonogenic cell survival versus N-methyl-N-nitrosourea (MNU) dose in the 12.5-200.0 mg/kg interval is exponential and characterized by Dsub(o)=29.15 mg/kg dose value. Large size tumours (15.0-17.0 g) are characterized by higher death rate of clonogenic cells (survivor fraction approximately 0.5%) than in 1.0-7.0 g tumours (survivor fraction 2-4%). That is, evidently, related to higher sensitivity of the resting tumour cells to MNU

  16. Solid state luminescence of CuI and CuNCS complexes with phenanthrolines and a new tris (aminomethyl) phosphine derived from N-methyl-2-phenylethanamine

    International Nuclear Information System (INIS)

    Starosta, Radosław; Komarnicka, Urszula K.; Puchalska, Małgorzata

    2014-01-01

    A new tris (aminomethyl) phosphine derived from N-methyl-2-phenylethanamine P(CH 2 N(CH 3 )CH 2 CH 2 Ph) 3 (1) has been synthesized and characterized by the NMR spectra. Also, three new copper(I) iodide or isothiocyanate complexes with 1 1,10-phenanthroline (phen) and 2,9-dimethyl-1,10-phenanthroline (dmp) [CuI(phen)P(CH 2 N(CH 3 )CH 2 CH 2 Ph) 3 ] (1P) CuI(dmp)P(CH 2 N(CH 3 )CH 2 CH 2 Ph) 3 ] (1I) and [CuNCS(dmp)P(CH 2 N(CH 3 )CH 2 CH 2 Ph) 3 ] (1T), have been synthesized and characterized by elemental analysis as well as studied by NMR, UV–vis, IR and luminescence spectroscopies. An X-ray structure of 1P complex revealed that the geometry around Cu(I) center in this complex is distorted pseudo-tetrahedral. Investigated complexes exhibit orange, rather weak photoluminescence in the solid state. This relatively low intensity may be related to the high flattening deformations of the molecular geometries in the excited triplet states On the basis of TDDFT calculations we confirmed that the absorbance and luminescence bands of (MX,MPR 3 )LCT as well as of (MX)LCT types result mainly from the transitions from the copper–iodine (or isothiocyanate) bonds and a small admixture of copper–phosphine bonds to antibonding orbitals of phen or dmp diimines. -- Highlights: • A novel tris(aminomethyl)phosphine is obtained from N-methyl-2-phenylethanamine. • Three new CuI and CuNCS complexes with phen or dmp and a novel phosphine are presented. • The obtained complexes are luminescent in the solid state. • Main absorbance and luminescence bands are of (MX,MPR 3 )LCT as well as (MX)LCT types

  17. N-Chlorosuccinimide (NCS): A Novel Initiator for Atom Transfer Radical Polymerization of Methyl Methacrylate

    Institute of Scientific and Technical Information of China (English)

    WANG,Xia-Yan; CHANG,Li-Qun; ZHOU,Hong; ZHANG,Ke-Da

    2006-01-01

    Atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) was achieved, using N-chlorosuccinimide (NCS) as an initiator together with catalytic system CuCl/PMDETA (N,N,N',N',N"-pentamethyldiethyl-enetriamine), CuCl/MA5-DETA (N,N,N',N',N"-penta(methylacrylate)diethylenetriamine), and CuCl/bipy (bipy=2,2'-bipyridyl) respectively. The results indicated that the polymerization possessed typical controlled/living radical polymerization characteristics. The analysis for terminal group of obtained polymer by 1H NMR proved that NCS is an initiator for ATRP. In comparison with NBS, the polymerization rate was slower and the resulted polymer had narrower molecular weight distribution (MWD) when NCS was employed as the initiator.

  18. Alkylation of deoxyribonucleic acid by carcinogens dimethyl sulphate, ethyl methanesulphonate, N-ethyl-N-nitrosourea and N-methyl-N-nitrosourea. Relative reactivity of the phosphodiester site thymidylyl(3'-5')thymidine.

    Science.gov (United States)

    Swenson, D H; Lawley, P D

    1978-01-01

    1. The ethyl phosphotriester of thymidylyl(3'-5')thymidine, dTp(Et)dT, was identified as a product from reaction of DNA with N-ethyl-N-nitrosourea, by procedures parallel to those reported previously for the methyl homologue produced by N-methyl-N-nitrosourea. 2. Enzymic degradation to yield alkyl phosphotriesters from DNA alkylated by these carcinogens and by dimethyl sulphate and ethyl methanesulphonate was studied quantitatively, and the relative yields of the triesters dTp(Alk)dT were determined. The relative reactivity of the phosphodiester group dTpdT to each of the four carcinogens was thus obtained, and compared with that of DNA overall, or with that of the N-7 atom of guanine in DNA. Relative reactivity of the phosphodiester group was lowest towards dimethyl sulphate, the least electrophilic of the reagents used, and was highest towards N-ethyl-N-nitrosourea, the most electrophilic reagent. 3. The nature of the alkyl group transferred also influenced reactivity of the phosphodiester site, since this site was relatively more reactive towards ethylation than would be predicted simply from the known Swain-Scott s values of the alkylating agents. It was therefore suggested that the steric accessibility of the weakly nucleophilic phosphodiester group on the outside of the DNA macromolecule favours its reaction with ethylating, as opposed to methylating, reagents. 4. Taking a value of the Swain-Scott nucleophilicity (n) of 2.5 for an average DNA nucleotide unit [Walles & Ehrenberg (1969) Acta Chem. Scand. 23, 1080-1084], a value of n of about 1 for the phosphodiester group was deduced, and this value was found to be 2-3 units less than that for the N-7 atom of guanine in DNA. 5. The reactivity of DNA overall was markedly high towards the alkylnitrosoureas, despite their relatively low s values. This was ascribed to an electrostatic factor that favoured reaction of the negatively charged polymer with alkyldiazonium cation intermediates. PMID:208508

  19. A multicomponent CuAAC "click" approach to a library of hybrid polydentate 2-pyridyl-1,2,3-triazole ligands: new building blocks for the generation of metallosupramolecular architectures.

    Science.gov (United States)

    Crowley, James D; Bandeen, Pauline H

    2010-01-14

    A one pot, multicomponent CuAAC reaction has been exploited for the safe generation of alkyl, benzyl or aryl linked polydentate pyridyl-1,2,3-triazole ligands from their corresponding halides, sodium azide and alkynes in excellent yields. The ligands have been fully characterised by elemental analysis, HR-ESMS, IR, (1)H and (13)C NMR and in two cases the structures were confirmed by X-ray crystallography. Additionally, we have examined the Ag(I) coordination chemistry of these ligands and found, using HR-ESMS, (1)H NMR, and X-ray crystallography, that both discrete and polymeric metallosupramolecular architectures can be formed.

  20. Methyl 3-(Quinolin-2-ylindolizine-1-carboxylate

    Directory of Open Access Journals (Sweden)

    Roumaissa Belguedj

    2015-12-01

    Full Text Available A novel compound, methyl 3-(quinolin-2-ylindolizine-1-carboxylate (2 has been synthesized by cycloaddition reaction of 1-(quinolin-2-ylmethylpyridinium ylide (1 with methyl propiolate in presence of sodium hydride in THF. The structure of this compound was established by IR, 1H-NMR, 13C-NMR and MS data

  1. 2-Methyl-1H-benzimidazol-3-ium hydrogen phthalate

    Directory of Open Access Journals (Sweden)

    YuanQi Yu

    2011-10-01

    Full Text Available The asymmetric unit of the title compound, C8H9N2+·C8H5O4−, contains two independent ion pairs. In each 2-methyl-1H-benzimidazolium ion, an intramolecular O—H...O bond forms an S(7 graph-set motif. In the crystal, the components are linked by N—H...O hydrogen bonds, forming chains along [210]. Further stabilization is provided by weak C—H...O hydrogen bonds.

  2. 7-Isopropylidene-N2,N3,N5,N6-tetramethoxy-N2,N3,N5,N6-tetramethylbicyclo[2.2.1]hepta-2,5-diene-2,3,5,6-tetracarboxamide

    Directory of Open Access Journals (Sweden)

    Benjamin Sahlmann

    2014-04-01

    Full Text Available Although the molecular structure of the title compound, C22H32N4O8, displays a twofold symmetry of the molecule including the methoxy and methyl substituents, no crystallographic twofold symmetry is observed in the X-ray structure analysis. The carbonyl O atoms alternately point to different sides of the plane defined by the carbonyl C atoms. Two methoxy groups are oriented inside the molecules cavity. The H atoms of two methyl groups are disordered over two orientations and were refined using a split model.

  3. Role of N-methyl-2-pyrrolidone for preparation of Fe{sub 3}O{sub 4}@SiO{sub 2} controlled the shell thickness

    Energy Technology Data Exchange (ETDEWEB)

    Wee, Sung-Bok [Hanyang University, Division of Materials Science and Engineering (Korea, Republic of); Oh, Hyeon-Cheol [Korea Nano Plus, Inc. (Korea, Republic of); Kim, Tae-Gyun; An, Gye-Seok; Choi, Sung-Churl, E-mail: choi0505@hanyang.ac.kr [Hanyang University, Division of Materials Science and Engineering (Korea, Republic of)

    2017-04-15

    We developed a simple and novel approach for the synthesis of Fe{sub 3}O{sub 4}@SiO{sub 2} nanoparticles with controlled shell thickness, and studied the mechanism. The introduction of N-methyl-2-pyrrolidone (NMP) led to trapping of monomer nuclei in single shell and controlled the shell thickness. Fe{sub 3}O{sub 4}@SiO{sub 2} controlled the shell thickness, showing a high magnetization value (64.47 emu/g). Our results reveal the role and change in the chemical structure of NMP during the core-shell synthesis process. NMP decomposed to 4-aminobutanoic acid in alkaline condition and decreased the hydrolysis rate of the silica coating process.

  4. Cfr and RlmN contain a single [4Fe-4S] cluster, which directs two distinct reactivities for S-adenosylmethionine: methyl transfer by SN2 displacement and radical generation.

    Science.gov (United States)

    Grove, Tyler L; Radle, Matthew I; Krebs, Carsten; Booker, Squire J

    2011-12-14

    The radical SAM (RS) proteins RlmN and Cfr catalyze methylation of carbons 2 and 8, respectively, of adenosine 2503 in 23S rRNA. Both reactions are similar in scope, entailing the synthesis of a methyl group partially derived from S-adenosylmethionine (SAM) onto electrophilic sp(2)-hybridized carbon atoms via the intermediacy of a protein S-methylcysteinyl (mCys) residue. Both proteins contain five conserved Cys residues, each required for turnover. Three cysteines lie in a canonical RS CxxxCxxC motif and coordinate a [4Fe-4S]-cluster cofactor; the remaining two are at opposite ends of the polypeptide. Here we show that each protein contains only the one "radical SAM" [4Fe-4S] cluster and the two remaining conserved cysteines do not coordinate additional iron-containing species. In addition, we show that, while wild-type RlmN bears the C355 mCys residue in its as-isolated state, RlmN that is either engineered to lack the [4Fe-4S] cluster by substitution of the coordinating cysteines or isolated from Escherichia coli cultured under iron-limiting conditions does not bear a C355 mCys residue. Reconstitution of the [4Fe-4S] cluster on wild-type apo RlmN followed by addition of SAM results in rapid production of S-adenosylhomocysteine (SAH) and the mCys residue, while treatment of apo RlmN with SAM affords no observable reaction. These results indicate that in Cfr and RlmN, SAM bound to the unique iron of the [4Fe-4S] cluster displays two reactivities. It serves to methylate C355 of RlmN (C338 of Cfr), or to generate the 5'-deoxyadenosyl 5'-radical, required for substrate-dependent methyl synthase activity. © 2011 American Chemical Society

  5. Maternal intake of methyl-group donors affects DNA methylation of metabolic genes in infants.

    Science.gov (United States)

    Pauwels, Sara; Ghosh, Manosij; Duca, Radu Corneliu; Bekaert, Bram; Freson, Kathleen; Huybrechts, Inge; Langie, Sabine A S; Koppen, Gudrun; Devlieger, Roland; Godderis, Lode

    2017-01-01

    Maternal nutrition during pregnancy and infant nutrition in the early postnatal period (lactation) are critically involved in the development and health of the newborn infant. The Maternal Nutrition and Offspring's Epigenome (MANOE) study was set up to assess the effect of maternal methyl-group donor intake (choline, betaine, folate, methionine) on infant DNA methylation. Maternal intake of dietary methyl-group donors was assessed using a food-frequency questionnaire (FFQ). Before and during pregnancy, we evaluated maternal methyl-group donor intake through diet and supplementation (folic acid) in relation to gene-specific ( IGF2 DMR, DNMT1 , LEP , RXRA ) buccal epithelial cell DNA methylation in 6 months old infants ( n  = 114) via pyrosequencing. In the early postnatal period, we determined the effect of maternal choline intake during lactation (in mothers who breast-fed for at least 3 months) on gene-specific buccal DNA methylation ( n  = 65). Maternal dietary and supplemental intake of methyl-group donors (folate, betaine, folic acid), only in the periconception period, was associated with buccal cell DNA methylation in genes related to growth ( IGF2 DMR), metabolism ( RXRA ), and appetite control ( LEP ). A negative association was found between maternal folate and folic acid intake before pregnancy and infant LEP (slope = -1.233, 95% CI -2.342; -0.125, p  = 0.0298) and IGF2 DMR methylation (slope = -0.706, 95% CI -1.242; -0.107, p  = 0.0101), respectively. Positive associations were observed for maternal betaine (slope = 0.875, 95% CI 0.118; 1.633, p  = 0.0241) and folate (slope = 0.685, 95% CI 0.245; 1.125, p  = 0.0027) intake before pregnancy and RXRA methylation. Buccal DNMT1 methylation in the infant was negatively associated with maternal methyl-group donor intake in the first and second trimester of pregnancy and negatively in the third trimester. We found no clear association between maternal choline intake

  6. 8-Hydroxy-2-methylquinolinium tetrachlorido(pyridine-2-carboxylato-κ2N,Ostannate(IV

    Directory of Open Access Journals (Sweden)

    Ezzatollah Najafi

    2011-02-01

    Full Text Available In the reaction of pyridine-2-carboxylic acid and stannic chloride in the presence of 2-methyl-8-hydroxyquinoline, the 2-methyl-8-hydroxyquinoline is protonated, yielding the title salt, (C10H10NO[SnCl4(C6H4NO2]. The SnIV atom in the anion is N,O-chelated by a pyridine-2-carboxylate in a cis-SnNOCl4 octahedral geometry. The cation is linked to the anion by an O—H...O hydrogen bond.

  7. MECP2 promoter methylation and X chromosome inactivation in autism.

    Science.gov (United States)

    Nagarajan, Raman P; Patzel, Katherine A; Martin, Michelle; Yasui, Dag H; Swanberg, Susan E; Hertz-Picciotto, Irva; Hansen, Robin L; Van de Water, Judy; Pessah, Isaac N; Jiang, Ruby; Robinson, Wendy P; LaSalle, Janine M

    2008-06-01

    Epigenetic mechanisms have been proposed to play a role in the etiology of autism. This hypothesis is supported by the discovery of increased MECP2 promoter methylation associated with decreased MeCP2 protein expression in autism male brain. To further understand the influence of female X chromosome inactivation (XCI) and neighboring methylation patterns on aberrant MECP2 promoter methylation in autism, multiple methylation analyses were peformed on brain and blood samples from individuals with autism. Bisulfite sequencing analyses of a region 0.6 kb upstream of MECP2 in brain DNA samples revealed an abrupt transition from a highly methylated region in both sexes to a region unmethylated in males and subject to XCI in females. Chromatin immunoprecipitation analysis demonstrated that the CCTC-binding factor (CTCF) bound to this transition region in neuronal cells, consistent with a chromatin boundary at the methylation transition. Male autism brain DNA samples displayed a slight increase in methylation in this transition region, suggesting a possible aberrant spreading of methylation into the MECP2 promoter in autism males across this boundary element. In addition, autistic female brain DNA samples showed evidence for aberrant MECP2 promoter methylation as an increase in the number of bisulfite sequenced clones with undefined XCI status for MECP2 but not androgen receptor (AR). To further investigate the specificity of MECP2 methylation alterations in autism, blood DNA samples from females and mothers of males with autism were also examined for XCI skewing at AR, but no significant increase in XCI skewing was observed compared to controls. These results suggest that the aberrant MECP2 methylation in autism brain DNA samples is due to locus-specific rather than global X chromosome methylation changes.

  8. "Spider"-shaped porphyrins with conjugated pyridyl anchoring groups as efficient sensitizers for dye-sensitized solar cells.

    Science.gov (United States)

    Stangel, Christina; Bagaki, Anthi; Angaridis, Panagiotis A; Charalambidis, Georgios; Sharma, Ganesh D; Coutsolelos, Athanasios G

    2014-11-17

    Two novel "spider-shaped" porphyrins, meso-tetraaryl-substituted 1PV-Por and zinc-metalated 1PV-Zn-Por, bearing four oligo(p-phenylenevinylene) (oPPV) pyridyl groups with long dodecyloxy chains on the phenyl groups, have been synthesized. The presence of four pyridyl groups in both porphyrins, which allow them to act as anchoring groups upon coordination to various Lewis acid sites, the conjugated oPPV bridges, which offer the possibility of electronic communication between the porphyrin core and the pyridyl groups, and the dodecyloxy groups, which offer the advantage of high solubility in a variety of organic solvents of different polarities and could prevent porphyrin aggregation, renders porphyrins 1PV-Por and 1PV-Zn-Por very promising sensitizers for dye-sensitized solar cells (DSSCs). Photophysical measurements, together with electrochemistry experiments and density functional theory calculations, suggest that both porphyrins have frontier molecular orbital energy levels that favor electron injection and dye regeneration in DSSCs. Solar cells sensitized by 1PV-Por and 1PV-Zn-Por were fabricated, and it was found that they show power conversion efficiencies (PCEs) of 3.28 and 5.12%, respectively. Photovoltaic measurements (J-V curves) together with incident photon-to-electron conversion efficiency spectra of the two cells reveal that the higher PCE value of the DSSC based on 1PV-Zn-Por is ascribed to higher short-circuit current (Jsc), open-circuit voltage (Voc), and dye loading values. Emission spectra and electrochemistry experiments suggest a greater driving force for injection of the photogenerated electrons into the TiO2 conduction band for 1PV-Zn-Por rather than its free-base analogue. Furthermore, electrochemical impedance spectroscopy measurements prove that the utilization of 1PV-Zn-Por as a sensitizer offers a high charge recombination resistance and, therefore, leads to a longer electron lifetime.

  9. Synthesis of DL-adrenaline (methyl C{sup 14}) (1961); Synthese de la DL-adrenaline (methyle {sup 14}C) (1961)

    Energy Technology Data Exchange (ETDEWEB)

    Pichat, L; Audinot, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1961-07-01

    The sodium derivative of 5-3-4 dibenzyl oxyphenyl 2-oxazolidinone reacted with methyl iodide {sup 14}C, in stoichiometric quantity, gives rise to the corresponding N-methyl {sup 14}C derivative. The oxazolidinone ring is opened by concentrated hydrochloric acid and the benzyl groups removed by catalytic hydrogenolysis. Adrenaline methyl {sup 14}C is then purified on Dowex 50 X-12 exchange resin. Overall-yield is 45 per cent based upon methyl iodide {sup 14}C. (author) [French] Le derive sode de la (dibenzyloxy-3-4-phenyl)-5 oxazolidinone-2 traite par l'iodure de methyle {sup 14}C, en proportion stoechiometrique, fournit le derive N-methyle {sup 14}C correspondant. Apres ouverture du cycle oxazolidinone par HCL concentre et debenzylation par hydrogenation catalytique, on purifie l'adrenaline (methyle {sup 14}C) par chromatographie sur resine echangeuse Dowex 50 X-12. Le rendement est de 45 pour cent par rapport a l'iodure de methyle {sup 14}C. (auteurs)

  10. Synthesis of DL-adrenaline (methyl C{sup 14}) (1961); Synthese de la DL-adrenaline (methyle {sup 14}C) (1961)

    Energy Technology Data Exchange (ETDEWEB)

    Pichat, L.; Audinot, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1961-07-01

    The sodium derivative of 5-3-4 dibenzyl oxyphenyl 2-oxazolidinone reacted with methyl iodide {sup 14}C, in stoichiometric quantity, gives rise to the corresponding N-methyl {sup 14}C derivative. The oxazolidinone ring is opened by concentrated hydrochloric acid and the benzyl groups removed by catalytic hydrogenolysis. Adrenaline methyl {sup 14}C is then purified on Dowex 50 X-12 exchange resin. Overall-yield is 45 per cent based upon methyl iodide {sup 14}C. (author) [French] Le derive sode de la (dibenzyloxy-3-4-phenyl)-5 oxazolidinone-2 traite par l'iodure de methyle {sup 14}C, en proportion stoechiometrique, fournit le derive N-methyle {sup 14}C correspondant. Apres ouverture du cycle oxazolidinone par HCL concentre et debenzylation par hydrogenation catalytique, on purifie l'adrenaline (methyle {sup 14}C) par chromatographie sur resine echangeuse Dowex 50 X-12. Le rendement est de 45 pour cent par rapport a l'iodure de methyle {sup 14}C. (auteurs)

  11. Configurational and constitutional information storage: multiple dynamics in systems based on pyridyl and acyl hydrazones.

    Science.gov (United States)

    Chaur, Manuel N; Collado, Daniel; Lehn, Jean-Marie

    2011-01-03

    The C=N group of hydrazones can undergo E/Z isomerization both photochemically and thermally, allowing the generation of a closed process that can be tuned by either of these two physical stimuli. On the other hand, hydrazine-exchange reactions enable a constitutional change in a given hydrazone. The two classes of processes: 1) configurational (physically stimulated) and 2) constitutional (chemically stimulated) give access to short-term and long-term information storage, respectively. Such transformations are reported herein for two hydrazones (bis-pyridyl hydrazone and 2-pyridinecarboxaldehyde phenylhydrazone) that undergo a closed, chemically or physically driven process, and, in addition, can be locked or unlocked at will by metal-ion coordination or removal. These features also extend to acyl hydrazones derived from 2-pyridinecarboxaldehyde. Similarly to the terpydine-like hydrazones, such acyl hydrazones can undergo both constitutional and configurational changes, as well as metal-ion coordination. All these types of hydrazones represent dynamic systems capable of acting as multiple state molecular devices, in which the presence of coordination sites furthermore allows the metal ion-controlled locking and unlocking of the interconversion of the different states. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Synthesis of N-[methyl-11C]hydromorphone by using multivariate strategies for optimization of radiochemical yields

    International Nuclear Information System (INIS)

    Rimland, Annika; Bergson, Goeran; Obenius, Ulf; Sjoeberg, Stefan; Langstroem, Bengt

    1987-01-01

    The synthesis of N-[methyl- 11 C]hydromorphone has been performed by using [ 11 C]methyl iodide and desmethyl hydromorphone in a mixture of dimethylsulphoxide and dimethylformamide as solvent. Optimization of the radiochemical yield by varying the reaction conditions was performed by using multivariate strategies. The labelled hydromorphone was obtained in 72% radiochemical yield in the alkylation reaction with [ 11 C]-methyl iodide, counted from the end of the [ 11 C]methyl iodide synthesis. N-[Methyl- 11 C]hydromorphone was obtained as a ready injectable pharmaceutical solution with a total synthesis time of 40 min and in a 10% total radiochemical yield, with a radiochemical purity > 99.5%, according to HPLC analysis. (author)

  13. Whole Genome DNA Methylation Analysis of Obstructive Sleep Apnea: IL1R2, NPR2, AR, SP140 Methylation and Clinical Phenotype.

    Science.gov (United States)

    Chen, Yung-Che; Chen, Ting-Wen; Su, Mao-Chang; Chen, Chung-Jen; Chen, Kuang-Den; Liou, Chia-Wei; Tang, Petrus; Wang, Ting-Ya; Chang, Jen-Chieh; Wang, Chin-Chou; Lin, Hsin-Ching; Chin, Chien-Hung; Huang, Kuo-Tung; Lin, Meng-Chih; Hsiao, Chang-Chun

    2016-04-01

    We hypothesized that DNA methylation patterns may contribute to disease severity or the development of hypertension and excessive daytime sleepiness (EDS) in patients with obstructive sleep apnea (OSA). Illumina's (San Diego, CA, USA) DNA methylation 27-K assay was used to identify differentially methylated loci (DML). DNA methylation levels were validated by pyrosequencing. A discovery cohort of 15 patients with OSA and 6 healthy subjects, and a validation cohort of 72 patients with sleep disordered breathing (SDB). Microarray analysis identified 636 DMLs in patients with OSA versus healthy subjects, and 327 DMLs in patients with OSA and hypertension versus those without hypertension. In the validation cohort, no significant difference in DNA methylation levels of six selected genes was found between the primary snoring subjects and OSA patients (primary outcome). However, a secondary outcome analysis showed that interleukin-1 receptor 2 (IL1R2) promoter methylation (-114 cytosine followed by guanine dinucleotide sequence [CpG] site) was decreased and IL1R2 protein levels were increased in the patients with SDB with an oxygen desaturation index > 30. Androgen receptor (AR) promoter methylation (-531 CpG site) and AR protein levels were both increased in the patients with SDB with an oxygen desaturation index > 30. Natriuretic peptide receptor 2 (NPR2) promoter methylation (-608/-618 CpG sites) were decreased, whereas levels of both NPR2 and serum C type natriuretic peptide protein were increased in the SDB patients with EDS. Speckled protein 140 (SP140) promoter methylation (-194 CpG site) was increased, and SP140 protein levels were decreased in the patients with SDB and EDS. IL1R2 hypomethylation and AR hypermethylation may constitute an important determinant of disease severity, whereas NPR2 hypomethylation and SP140 hypermethylation may provide a biomarker for vulnerability to EDS in OSA. A commentary on this article appears in this issue on page 723. © 2016

  14. Bardoxolone Methyl Improves Kidney Function in Patients with Chronic Kidney Disease Stage 4 and Type 2 Diabetes: Post-Hoc Analyses from Bardoxolone Methyl Evaluation in Patients with Chronic Kidney Disease and Type 2 Diabetes Study

    Science.gov (United States)

    Chin, Melanie P.; Bakris, George L.; Block, Geoffrey A.; Chertow, Glenn M.; Goldsberry, Angie; Inker, Lesley A.; Heerspink, Hiddo J.L.; O'Grady, Megan; Pergola, Pablo E.; Wanner, Christoph; Warnock, David G.; Meyer, Colin J.

    2018-01-01

    Background Increases in measured inulin clearance, measured creatinine clearance, and estimated glomerular filtration rate (eGFR) have been observed with bardoxolone methyl in 7 studies enrolling approximately 2,600 patients with type 2 diabetes (T2D) and chronic kidney disease (CKD). The largest of these studies was Bardoxolone Methyl Evaluation in Patients with Chronic Kidney Disease and Type 2 Diabetes (BEACON), a multinational, randomized, double-blind, placebo-controlled phase 3 trial which enrolled patients with T2D and CKD stage 4. The BEACON trial was terminated after preliminary analyses showed that patients randomized to bardoxolone methyl experienced significantly higher rates of heart failure events. We performed post-hoc analyses to characterize changes in kidney function induced by bardoxolone methyl. Methods Patients in ­BEACON (n = 2,185) were randomized 1: 1 to receive once-daily bardoxolone methyl (20 mg) or placebo. We compared the effects of bardoxolone methyl and placebo on a post-hoc composite renal endpoint consisting of ≥30% decline from baseline in eGFR, eGFR <15 mL/min/1.73 m2, and end-stage renal disease (ESRD) events (provision of dialysis or kidney transplantation). Results Consistent with prior studies, patients randomized to bardoxolone methyl experienced mean increases in eGFR that were sustained through study week 48. Moreover, increases in eGFR from baseline were sustained 4 weeks after cessation of treatment. Patients randomized to bardoxolone methyl were significantly less likely to experience the composite renal endpoint (hazards ratio 0.48 [95% CI 0.36–0.64]; p < 0.0001). Conclusions Bardoxolone methyl preserves kidney function and may delay the onset of ESRD in patients with T2D and stage 4 CKD. PMID:29402767

  15. Top-Contact Pentacene-Based Organic Thin Film Transistor (OTFT) with N, N'-Bis(3-Methyl Phenyl)- N, N'-Diphenyl Benzidine (TPD)/Au Bilayer Source-Drain Electrode

    Science.gov (United States)

    Borthakur, Tribeni; Sarma, Ranjit

    2018-01-01

    A top-contact Pentacene-based organic thin film transistor (OTFT) with N, N'-Bis (3-methyl phenyl)- N, N'-diphenyl benzidine (TPD)/Au bilayer source-drain electrode is reported. The devices with TPD/Au bilayer source-drain (S-D) electrodes show better performance than the single layer S-D electrode OTFT devices. The field-effect mobility of 4.13 cm2 v-1 s-1, the on-off ratio of 1.86 × 107, the threshold voltage of -4 v and the subthreshold slope of .27 v/decade, respectively, are obtained from the device with a TPD/Au bilayer source-drain electrode.

  16. Thermodynamic study of 2-methyl-tetrahydrofuran with isomeric chlorobutanes

    International Nuclear Information System (INIS)

    Aldea, M. Eugenia; Martin, Santiago; Artigas, Hector; Lopez, Maria C.; Lafuente, Carlos

    2005-01-01

    Excess molar volumes, V E , isentropic compressibility deviations, Δκ S , and excess molar enthalpies, H E , for the binary mixtures 2-methyl-tetrahydrofuran with 1-chlorobutane, 2-chlorobutane, 2-methyl-1-chloropropane and 2-methyl-2-chloropropane have been determined at temperatures 298.15 and 313.15 K, excess molar enthalpies were only measured at 298.15 K. We have applied the Prigogine-Flory-Patterson (PFP) theory to these mixtures at 298.15 K

  17. tert-Butyl 2-methyl-2-(4-nitrobenzoylpropanoate

    Directory of Open Access Journals (Sweden)

    Chelsey M. Crosse

    2010-02-01

    Full Text Available The title compound, C15H19NO5, is bent with a dihedral angle of 61.8 (2° between the mean planes of the benzene ring and a group encompassing the ester functionality (O=C—O—C. The dihedral angle of 0.8 (2° between the mean planes of the nitro group and the benzene ring indicates near coplanarity. In the crystal, each molecule is linked to four adjacent molecules by weak C—H...O hydrogen-bonding interactions. Both benzene H atoms ortho to the ketone O atom form C—H...O hydrogen bonds with the keto O atoms of two neighboring molecules (of the keto and ester groups, respectively, and the two other interactions involve the H atoms from a methyl group of the dimethyl residue, displaying C—H...O interactions with the O atoms of the nitro groups. These four interactions for each molecule lead to the formation of two-dimensional sheets with a hydrophilic interior, held together by weak hydrogen-bonded interactions, and a hydrophobic exterior composed of protruding methyl groups which interstack with the methyl groups in adjacent sheets.

  18. Crystal and molecular structure studies of (Z)-N-methyl-C-4-substituted phenyl nitrones by XRD, DFT, FTIR and NMR methods

    Science.gov (United States)

    Lasri, Jamal; Eltayeb, Naser Eltaher; Haukka, Matti; Alghamdi, Yousef

    2017-01-01

    (Z)-N-methyl-C-4-substituted phenyl nitrones -O+N(Me)=C(H)R (Z-2a R = 4-ClC6H4, Z-2b R = 4-NO2C6H4, Z-2c R = 4-CH3OC6H4) were synthesized and characterized by elemental analyses, FTIR, 1H, 13C and DEPT-135 NMR spectroscopy and also by single crystal X-ray diffraction (in the case of Z-2a and Z-2b). The geometries of the nitrone molecules Z-2a, Z-2b and Z-2c and their E-isomers; (E)-N-methyl-C-4-chlorophenyl nitrone E-2a, (E)-N-methyl-C-4-nitrophenyl nitrone E-2b and (E)-N-methyl-C-4-methoxyphenyl nitrone E-2c were optimized using density functional theory (DFT) at the B3LYP/6-311++G(d,p) level of theory. The theoretical vibrational frequencies obtained by DFT calculations are in good agreement with the experimental values. The electronics structures were described in terms of the distribution of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO). Gauge independent atomic orbital (GIAO) method was used to calculate the NMR spectra, the correlation between the calculated and experimental chemical shifts is mostly in the range of 0.94-0.97 for 1H, whereas, the correlation for 13C is 0.99. Thermodynamics study showed that the Z-isomer is favoured than E-isomer with energy barrier of 7.1, 7.2 and 7.1 kcal/mol for Z-2a, Z-2b and Z-2c, respectively. The abundance of the most stable species Z-isomers is equal to 99.99% for all three compounds at 298 K in gas phase.

  19. Immobilization of tris(2 pyridyl methylamine in a PVC-Membrane Sensor and Characterization of the Membrane Properties

    Directory of Open Access Journals (Sweden)

    Rezayi Majid

    2012-05-01

    Full Text Available Abstract Background Due to the increasing industrial use of titanium compounds, its determination is the subject of considerable efforts. The ionophore or membrane active recognition is the most important component of any polymeric membrane sensor. The sensor’s response depends on the ionophore and bonding between the ionophore and the target ion. Ionophores with molecule-sized dimensions containing cavities or semi-cavities can surround the target ion. The bond between the ionophore and target ion gives different selectivity and sensitivity toward the other ions. Therefore, ionophores with different binding strengths can be used in the sensor. Results In the present work, poly (vinyl chloride (PVC based membrane incorporating tris (2 pyridyl methylamine (tpm as an ionophore has been prepared and explored as a titanium(III selective sensor. Conclusions The strengths of the ion–ionophore (Ti(OH2+-tpm interactions and the role of ionophore on membrane were tested by various techniques such as elemental analysis, UV–vis, Fourier transform infrared (FTIR spectroscopy, scanning electron microscopy (SEM, and powder X-ray diffraction (XRD. All data approved the successful incorporation of organic group via covalent bond.

  20. Synthesis, structural characterization, and thermal stability studies of heteroleptic cadmium(II) dithiocarbamate with different pyridyl groups

    Science.gov (United States)

    Onwudiwe, Damian C.; Hosten, Eric C.

    2018-01-01

    The synthesis, characterization and crystal structures of three chloroform solvated adducts of cadmium with mixed ligands of N-alkyl-N-phenyldithiocarbamate and pyridine, 2,2-bipyridine and 1, 10 phenanthroline represented as [CdL1L2 (py)2]·CHCl3(1), [CdL1L2bpy]•CHCl3(2), and [CdL1L2phen]•CHCl3(3) (LI = N-methyl-N-phenyldithiocarbamate, L2 = N-ethyl-N-phenyldithiocarbamate, py = pyridine, bpy = 2,2-bipyridine and phen = 1,10-phenanthroline) respectively are reported. Complex 1, which crystallized in the monoclinic space group P-1, is a centrosymmetric dimeric structure where each Cd center is bonded to two monodentate pyridine, a bidentate terminal dithiocarbamate, and another bidentate bridging dithiocarbamate to form a four-membered ring. Complex 2 crystallized in the monoclinic space group P21/c, with four discrete monomeric molecules in the asymmetric unit. The structure presents a cadmium atom coordinated by two sulphur atoms of a dithiocarbamate ligand and two nitrogen atoms of the 2,2‧-bipyridine to form a CdS4N2 fragment, thus giving the structure around the Cd atom a distorted trigonal prism geometry. Complex 3 contains two discrete monomeric molecules of (phenanthroline) (N, N-methyl phenyl-N, N-ethyl phenyl dithiocarbamato)cadmium (II) per unit cell, and the complex crystallized in the triclinic space group P-1. The structure showed that the Cd atom is bonded to two bidentate dithiocarbamate ligands and to one bidentate phenanthroline ligand in a distorted trigonal prism geometry. All the compounds resulted in CdS as residue upon thermal decomposition process conducted under inert atmosphere.

  1. Effects of combined action of γ-irradiation and sulfur dioxide or N-methyl-N'-nitro-N-nitrosoguanidin on bacteria and higher plants

    International Nuclear Information System (INIS)

    Kal'chenko, V.A.; Lotareva, O.V.; Spirin, D.A.; Karaban', R.T.; Mal'tseva, L.N.; Ignat'ev, A.A.

    1988-01-01

    Effect of combined action of of gamma-irradiation and sulfur dioxide or N-methyl-N-nitro-N-nitrosoguanidin on baceria (Bacillus subtilis) and higher plants (Hordeum vulgare L., Pinus sylvestris L.) have been studied. The number of barley germ root cells with chromosomal aberrations depends on the order of treatment with the studied agents. The coefficients of SO 2 and gamma-irradiation correlation fluctuate from 1,3 to 2,6 in the above experiments. In experiments with pine seedlings, these correlation coefficients were similar to additive ones. The data obtained suggest that the pattern of action of the agents is determined by the radiation sensitivity of objects and the order of action of the agents

  2. Solubility and solution thermodynamics of 2-methyl-6-nitroaniline in ten organic solvents at elevated temperatures

    International Nuclear Information System (INIS)

    Cong, Yang; Wang, Jian; Du, Cunbin; Han, Shuo; Zhao, Hongkun

    2016-01-01

    Highlights: • Solubility of 2-methyl-6-nitroaniline in ten solvents were determined. • The solubility were correlated with four thermodynamic models. • Standard dissolution enthalpy and excess enthalpy of the solutions were computed. - Abstract: Knowledge of solubility for 2-methyl-6-nitroaniline in different solvents is essential for its purification and further theoretical studies. In this paper, the solid-liquid equilibrium for 2-methyl-6-nitroaniline in ten pure organic solvents (methanol, ethanol, n-propanol, isopropanol, toluene, ethyl acetate, acetonitrile, acetone, cyclohexane and 1,4-dioxane) was established using the isothermal saturation method at temperatures T = (278.15–313.15) K under pressure of 101.2 kPa, and the solubility of 2-methyl-6-nitroaniline in these solvents were determined by a high-performance liquid chromatography (HPLC). In general, the mole fraction solubility followed the following order from high to low in different solvents: 1,4-dioxane (0.1799–0.3390) > acetone (0.1128–0.3010) > ethyl acetate (0.08414–0.2654) > acetonitrile (0.04179–0.2027) > toluene (0.02367–0.1104) > n-propanol (0.01080–0.04514) > ethanol (0.01020–0.04202) > isopropanol (0.008595–0.03763) > methanol (0.007391–0.03198) > cyclohexane (0.001027–0.005617). The modified Apelblat equation, λh equation, Wilson model and NRTL model were employed to correlate the measured solubility data of 2-methyl-6-nitroaniline in the selected solvents. Results indicated that the largest values of RAD and RMSD acquired by the four models were less than 0.76% and 9.13 × 10"−"4, respectively. The modified Apelblat equation provided better results than the other three models. Furthermore, the standard dissolution enthalpy and excess enthalpy of the solutions were computed from the solubility values. The standard dissolution enthalpies vary within the range from (14.88 to 45.57) kJ·mol"−"1 and are all positive, the dissolution process of 2-methyl-6

  3. Design, synthesis and pharmacological evaluation of some novel derivatives of 1-{[3-(furan-2-yl-5-phenyl-4,5-dihydro-1,2-oxazol-4-yl]methyl}-4-methyl piperazine

    Directory of Open Access Journals (Sweden)

    Jagdish Kumar

    2017-01-01

    Full Text Available A novel series of 1-{[3-(furan-2-yl-5-substituted phenyl-4,5-dihydro-1,2-oxazol-4-yl]methyl}-4-methyl piperazine, compounds 3a–l have been synthesized. The synthetic work was carried out beginning from 2-acetylfuran through Claisen Schmidt condensation with different types of aromatic aldehyde, affording 1-(furan-2-yl-3-substitutedphenylprop-2-en-1-ones which on cyclization with hydroxylamine hydrochloride resulted in 3-(furan-2-yl-5-substitutedphenyl-4,5-dihydro-1,2-oxazole formation. The isoxazolines were subjected to Mannich’s reaction in the presence of N-methyl piperazine to produce the desired product. The chemical structures of the compounds were proved by IR, 1H NMR, 13C-NMR and Mass spectrometric data. The antidepressant activities of the compounds were investigated by Porsolt’s behavioral despair (forced swimming test on albino mice. Moreover, the antianxiety activity of the newly synthesized compounds was investigated by the plus maze method. Compounds 3a and 3k reduced the duration of immobility times of 152.00–152.33% at 10 mg/kg dose level and compounds 3a and 3k have also shown significant antianxiety activity.

  4. Synthesis of N-methyl-N-formyltyramine, a new {beta}-phenethylamide derivative isolated from Cyathobasis fruticulosa (Bunge) aellen

    Energy Technology Data Exchange (ETDEWEB)

    Larghi, Enrique L.; Kaufman, Teodoro S. [Universidad Nacional de Rosario, Rosario (Argentina). Instituto de Quimica Organica de Sintesis (IQUIOS); Universidad Nacional de Rosario, Rosario (Argentina). Facultad de Ciencias Bioquimicas y Farmaceuticas; E-mail: tkaufman@fbioyf.unr.edu.ar

    2006-05-15

    The synthesis of N-methyl-N-formyltyramine, a novel {beta}-phenethylamide derivative isolated from Cyathobasis fructiculosa (Bunge) Aellen, is reported. The natural product was prepared in six steps and good overall yield from 4-hydroxybenzaldehyde. (author)

  5. Synthesis of block copolymers derived from N-trityl-(S)-serine and pyrene end-labeled poly(methyl methacrylate) or poly(N-isopropylacrylamide) via ATRP

    International Nuclear Information System (INIS)

    Buruiana, Emil C.; Podasca, Viorica; Buruiana, Tinca

    2012-01-01

    A new monomer bearing N-trityl-L-serine methyl ester in structure, methacryloyloxyethyl carbamoyloxy–N-trityl methyl serine (MTS), was prepared to be further polymerized by atom transfer radical polymerization (ATRP) with pyrene-endcapped poly(methyl methacrylate) (Py–PMMA–Br) or poly(N-isopropylacrylamide) (Py–PNIPA–Br). The resulting block copolymers, poly(methyl methacrylate–block–methacryloyloxyethyl carbamoyloxy–N-trityl methyl serine) (Py–PMMA–b–PMTS) and poly(N-isopropylacrylamide–block–methacryloyloxyethyl carbamoyloxy–N-trityl methyl serine (Py–PNIPA–b–PMTS) were characterized by 1 H ( 13 C) NMR, ultraviolet, FTIR and fluorescence spectroscopy, thermal analysis, differential scanning calorimetry (DSC), atomic force microscopy (AFM), scanning electron microscopy (SEM), and gel permeation chromatography (GPC) measurements. The chemical composition in Py–PMMA–b–PMTS was estimated from the 1 H NMR analysis that indicated a ratio of the repeating units of 46:19 (MMA:MTS). For the Py–PNIPA–b–PMTS the composition rate in the copolymer was 61:25 (NIPA:MTS). Quenching of the pyrene species with N,N-diethylaniline, nitrobenzene, nitrophenol, potassium iodide, p-nitrotoluene and tetracyanoquinodimethane (TCNQ) in DMF solution excited at 348 nm was evidenced, more efficiently being nitrophenol and TCNQ. In this case, the monomer emission at 388–409 nm underwent a significant decrease caused of an electron transfer from the electron-reach photoexcited pyrene molecule to the electron-deficient quenchers. - Highlights: ► Diblock copolymers combine the fluorescence of pyrene–PMMA (PNIPA) with the characteristics of PMTS. ► Such copolymers could be used for nitroderivatives detecting. ► UV/vis and fluorescence measurements give a good correlation for LCST of Py–PNIPA–Br.

  6. Synthesis of block copolymers derived from N-trityl-(S)-serine and pyrene end-labeled poly(methyl methacrylate) or poly(N-isopropylacrylamide) via ATRP

    Energy Technology Data Exchange (ETDEWEB)

    Buruiana, Emil C., E-mail: emilbur@icmpp.ro [Petru Poni Institute of Macromolecular Chemistry, 41A Gr. Ghica Voda Alley 700487, Iasi (Romania); Podasca, Viorica; Buruiana, Tinca [Petru Poni Institute of Macromolecular Chemistry, 41A Gr. Ghica Voda Alley 700487, Iasi (Romania)

    2012-10-15

    A new monomer bearing N-trityl-L-serine methyl ester in structure, methacryloyloxyethyl carbamoyloxy-N-trityl methyl serine (MTS), was prepared to be further polymerized by atom transfer radical polymerization (ATRP) with pyrene-endcapped poly(methyl methacrylate) (Py-PMMA-Br) or poly(N-isopropylacrylamide) (Py-PNIPA-Br). The resulting block copolymers, poly(methyl methacrylate-block-methacryloyloxyethyl carbamoyloxy-N-trityl methyl serine) (Py-PMMA-b-PMTS) and poly(N-isopropylacrylamide-block-methacryloyloxyethyl carbamoyloxy-N-trityl methyl serine (Py-PNIPA-b-PMTS) were characterized by {sup 1}H ({sup 13}C) NMR, ultraviolet, FTIR and fluorescence spectroscopy, thermal analysis, differential scanning calorimetry (DSC), atomic force microscopy (AFM), scanning electron microscopy (SEM), and gel permeation chromatography (GPC) measurements. The chemical composition in Py-PMMA-b-PMTS was estimated from the {sup 1}H NMR analysis that indicated a ratio of the repeating units of 46:19 (MMA:MTS). For the Py-PNIPA-b-PMTS the composition rate in the copolymer was 61:25 (NIPA:MTS). Quenching of the pyrene species with N,N-diethylaniline, nitrobenzene, nitrophenol, potassium iodide, p-nitrotoluene and tetracyanoquinodimethane (TCNQ) in DMF solution excited at 348 nm was evidenced, more efficiently being nitrophenol and TCNQ. In this case, the monomer emission at 388-409 nm underwent a significant decrease caused of an electron transfer from the electron-reach photoexcited pyrene molecule to the electron-deficient quenchers. - Highlights: Black-Right-Pointing-Pointer Diblock copolymers combine the fluorescence of pyrene-PMMA (PNIPA) with the characteristics of PMTS. Black-Right-Pointing-Pointer Such copolymers could be used for nitroderivatives detecting. Black-Right-Pointing-Pointer UV/vis and fluorescence measurements give a good correlation for LCST of Py-PNIPA-Br.

  7. The respective N-hydroxypyrazole analogues of the classical glutamate receptor ligands ibotenic acid and (RS)-2-amino-2-(3-hydroxy-5-methyl-4-isoxazolyl)acetic acid

    DEFF Research Database (Denmark)

    Clausen, Rasmus P; Hansen, Kasper B; Calí, Patrizia

    2004-01-01

    We have determined the pharmacological activity of N-hydroxypyrazole analogues (3a and 4a) of the classical glutamate receptor ligands ibotenic acid and (RS)-2-amino-2-(3-hydroxy-5-methyl-4-isoxazolyl)acetic acid (AMAA), as well as substituted derivatives of these two compounds. The pharmacological...... partial agonism to antagonism with increasing substituent size, substitution abolishes affinity for mglu1 and mglu4 receptors. Ligand- and receptor-based modelling approaches assist in explaining these pharmacological trends among the metabotropic receptors and suggest a mechanism of partial agonism...

  8. Inhibition of mutagenicity of N-methyl-N-nitrosourea by ellagic acid

    International Nuclear Information System (INIS)

    Dixit, R.; Gold, B.

    1986-01-01

    Ellagic acid (EA), a plant phenol present in a variety of soft fruits and vegetables, has been shown to possess antimutagenic and anticarcinogenic properties against bay region diol epoxide of polycyclic aromatic hydrocarbons. It is suggested that EA forms an adduct with diol epoxide of benzo (α) pyrene and thus prevents its binding to DNA. To better understand the mechanism of reactivity and inhibition properties of EA, we studied the effect of EA on mutagenicity and DNA alkylation of carcinogenic N-nitroso compounds, including N-methyl-N-nitrosourea (MNU) and N-methyl-N'-nitro-Nnitrosoguanidine (MNNG). MNU and MNNG are direct-acting mutagens requiring no metabolic activation. MNU showed a linear dose response between the concentration range of 50 to 400 nmole in an Ames/Salmonella mammalian mutagenicity test. EA at concentrations of 100, 250, 500, and 1,000 nmole inhibited the mutagenicity of MNU (400 nmole) by 3, 13, 45,and 60%, respectively. MNNG produced a nonlinear dose response in mutagenicity between the concentrations of 0.5 to 4 nmole. EA showed no appreciable inhibition of MNNG mutagenicity. Inhibition of DNA alkylation by MNU and MNNG by EA was studied by preincubating 50 to 200 nmole of EA with 200 nmole of ( 3 H)-MNU or ( 3 H)-MNNG for 10 min at 37 0 c, followed by incubation of polymer deoxyguanosine: deoxycytosine (poly dG:dC) (1 unit) overnight. EA caused no inhibitory effect on MNNG alkylation of poly dG:dC. Experiments on the effect of EA on alkylation of DNA and formation of nucleoside adducts by MNU are in progress, and results will be discussed with reference to MNU and MNNG mutagenicity and EA inhibition

  9. Anti-N-methyl-D-aspartate receptor encephalitis in Taiwan--a comparison between children and adults.

    Science.gov (United States)

    Lin, Jainn-Jim; Lin, Kuang-Lin; Hsia, Shao-Hsuan; Chou, Min-Liang; Hung, Po-Cheng; Hsieh, Meng-Ying; Chou, I-Jun; Wang, Huei-Shyong

    2014-06-01

    Since the discovery of antibodies against the N-methyl-D-aspartate receptor in 2007, anti-N-methyl-D-aspartate receptor encephalitis is increasingly recognized worldwide. We compare the clinical features of adults and children with this disorder in Taiwan. Patients admitted to Chang Gung Memorial Hospital and Chang Gung Children's Hospital and those who were referred from other institutions because of unknown encephalitis from 2009 to 2013 were enrolled, and their clinical features were analyzed. Data on cases from a review of the literature were also included in the analysis. Twelve patients (10 females) aged between 7 years and 28 years with anti-N-methyl-D-aspartate receptor encephalitis were identified. Six patients (50%) were Anti-N-methyl-D-aspartate receptor encephalitis is increasingly recognized in Taiwan. It is characterized by its clinical features, predominantly affects females with and/or without an ovarian tumor, and it is a potentially treatable disorder. It is important for neurologists to be familiar with the clinical presentations of the disease in children and young adults. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Pulse radiolysis study on free radical scavenger edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one). 2: A comparative study on edaravone derivatives

    International Nuclear Information System (INIS)

    Hata, Kuniki; Katsumura, Yosuke; Lin, M.; Yamashita, Shinichi; Muroya, Yusa; Fu Haiying; Nakagawa, Hidehiko

    2011-01-01

    A comparative study using the pulse radiolysis technique was carried out to investigate transient absorption spectra and rate constants for the reactions of OH radical and N 3 radical with edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) and its four analogue compounds, 1,3-dimethyl-2-pyrazolin-5-one, 3-methyl-1-(pyridin-2-yl)-2-pyrazolin-5-one, 1-phenyl-3-trifluoromethyl-2-pyrazolin-5-one and 1-(4-chlorophenyl)-3-methyl-2-pyrazolin-5-one. The results showed that, unlike reaction mechanisms previously proposed, the phenyl group of edaravone played an important role in the reaction with OH radical and OH adducts to the phenyl group were formed. Quantum chemical calculations also strongly supported this attribution and suggested that the most favorable site for attacks by OH radical is the ortho position of the phenyl group. Moreover, the rate constants for the reactions of edaravone and its analogues towards OH radical and N 3 radical were about 8.0 x 10 9 , and 4.0 x 10 9 dm 3 mol -1 s -1 , respectively. Edaravone displayed higher reactivity compared to the others, in contrast to a previous report in which 3-methyl-1-(pyridin-2-yl)-2-pyrazolin-5-one showed the highest reactivity towards Hydroxyl radical OH. (author)

  11. X-ray diffraction, vibrational and quantum chemical investigations of 2-methyl-4-nitroanilinium trichloroacetate trichloroacetic acid

    Science.gov (United States)

    Arjunan, V.; Marchewka, Mariusz K.; Pietraszko, A.; Kalaivani, M.

    2012-11-01

    The structural investigations of the molecular complex of 2-methyl-4-nitroaniline with trichloroacetic acid, namely 2-methyl-4-nitroanilinium trichloroacetate trichloroacetic acid (C11H10Cl6N2O6) have been performed by means of single crystal and powder X-ray diffraction method. The complex was formed with accompanying proton transfer from trichloroacetic acid molecule to 2-methyl-4-nitroaniline. The studied crystal is built up of singly protonated 2-methyl-4-nitroanilinium cations, trichloroacetate anions and neutral trichloroacetic acid molecules. The crystals are monoclinic, space group P21/c, with a = 14.947 Å, b = 6.432 Å, c = 19.609 Å and Z = 4. The vibrational assignments and analysis of 2-methyl-4-nitroanilinium trichloroacetate trichloroacetic acid have also been performed by FTIR, FT-Raman and far-infrared spectral studies. More support on the experimental findings were added from the quantum chemical studies performed with DFT (B3LYP) method using 6-31G**, cc-pVDZ, 6-31G and 6-31++G basis sets. The structural parameters, energies, thermodynamic parameters and the NBO charges of 2M4NATCA were also determined by the DFT methods.

  12. Discovery of (+)-N-(3-aminopropyl)-N-[1-(5-benzyl-3-methyl-4-oxo-[1,2]thiazolo[5,4-d]pyrimidin-6-yl)-2-methylpropyl]-4-methylbenzamide (AZD4877), a kinesin spindle protein inhibitor and potential anticancer agent.

    Science.gov (United States)

    Theoclitou, Maria-Elena; Aquila, Brian; Block, Michael H; Brassil, Patrick J; Castriotta, Lillian; Code, Erin; Collins, Michael P; Davies, Audrey M; Deegan, Tracy; Ezhuthachan, Jayachandran; Filla, Sandra; Freed, Ellen; Hu, Haiqing; Huszar, Dennis; Jayaraman, Muthusamy; Lawson, Deborah; Lewis, Paula M; Nadella, Murali V P; Oza, Vibha; Padmanilayam, Maniyan; Pontz, Timothy; Ronco, Lucienne; Russell, Daniel; Whitston, David; Zheng, Xiaolan

    2011-10-13

    Structure-activity relationship analysis identified (+)-N-(3-aminopropyl)-N-[1-(5-benzyl-3-methyl-4-oxo-[1,2]thiazolo[5,4-d]pyrimidin-6-yl)-2-methylpropyl]-4-methylbenzamide (AZD4877), from a series of novel kinesin spindle protein (KSP) inhibitors, as exhibiting both excellent biochemical potency and pharmaceutical properties suitable for clinical development. The selected compound arrested cells in mitosis leading to the formation of the monopolar spindle phenotype characteristic of KSP inhibition and induction of cellular death. A favorable pharmacokinetic profile and notable in vivo efficacy supported the selection of this compound as a clinical candidate for the treatment of cancer.

  13. Hallucinogen-like effects of 2-([2-(4-cyano-2,5-dimethoxyphenyl) ethylamino]methyl)phenol (25CN-NBOH), a novel N-benzylphenethylamine with 100-fold selectivity for 5-HT2A receptors, in mice

    DEFF Research Database (Denmark)

    Fantegrossi, William E; Gray, Bradley W; Bailey, Jessica M

    2015-01-01

    RATIONALE: 2-([2-(4-cyano-2,5-dimethoxyphenyl)ethylamino]methyl)phenol (25CN-NBOH) is structurally similar to N-benzyl substituted phenethylamine hallucinogens currently emerging as drugs of abuse. 25CN-NBOH exhibits dramatic selectivity for 5-HT2A receptors in vitro, but has not been behaviorally...... an intermediate degree of generalization (55 %) for the DOI training dose, and these interoceptive effects were attenuated by M100907. Finally, 25CN-NBOH did not generalize to M100907 at any dose, but ketanserin fully substituted in these animals. CONCLUSIONS: 25CN-NBOH was behaviorally active, but less effective...

  14. mer-Bis[3,5-difluoro-2-(2-pyridylphenyl-κ2C1,N]{5-(2-pyridyl-κN-3-[3-(4-vinylbenzyloxyphenyl]-1,2,4-triazol-1-ido}iridium(III methanol solvate

    Directory of Open Access Journals (Sweden)

    Peter G. Jones

    2010-01-01

    Full Text Available In the title compound, [Ir(C11H6F2N2(C22H17N4O]·CH3OH, the coordination at iridium is essentially octahedral, but with distortions associated with the bite angles of the ligands [76.25 (9–80.71 (12°] and the differing trans influences of C and N ligands [Ir—N = 2.04 Å (average trans to N but 2.14 Å trans to C]. All three bidentate ligands have coordinating ring systems that are almost coplanar [interplanar angles = 1.7 (1–3.8 (2°]. The vinylbenzyl group is disordered over two positions with occupations of 0.653 (4 and 0.347 (4. The methanol solvent molecule is involved in a classical O—H...N hydrogen bond to a triazole N atom.

  15. 4-[4-(4-Fluorophenyl-2-methyl-5-oxo-2,5-dihydroisoxazol-3-yl]-1-methylpyridinium iodide–4-[3-(4-fluorophenyl-2-methyl-5-oxo-2,5-dihydroisoxazol-4-yl]-1-methylpyridinium iodide (0.6/0.4

    Directory of Open Access Journals (Sweden)

    Simona Margutti

    2008-01-01

    Full Text Available The crystal structure of the title compound, C16H16FN2O2+·I−, was determined as part of a study of the biological activity of isoxazolone derivatives as p38 mitogen-activated protein kinase (MAPK inhibitors. The X-ray crystal structure of 4-[4-(4-fluorophenyl-2-methyl-5-oxo-2,5-dihydroisoxazol-3-yl]-1-methylpyridinium iodide showed the presence of the regioisomer 4-[3-(4-fluorophenyl-2-methyl-5-oxo-2,5-dihydroisoxazol-4-yl]-1-methylpyridinium iodide. The synthesis of the former compound was achieved by reacting 4-(4-fluorophenyl-3-(4-pyridylisoxazol-5(2H-one after treatment with Et3N in dimethylformamide, with iodomethane. The unexpected formation of the regioisomer could be explained by a rearrangement occurring via aziridine of the isoxazolone compound. The regioisomers have site occupancies of 0.632 (4/0.368 (4. The two six members rings make a dihedral angle of 66.8 (2°.

  16. Dynamics and disorder of methyl group in the different phases of 2,6-dimethyl pyrazine, 4-methyl pyridine and 4-methyl pyridine N-oxide

    International Nuclear Information System (INIS)

    Kaiser Morris, E.

    1997-01-01

    The thermal and mechanical properties of organic compounds are well known to be strongly correlated with the orientational freedom of its molecules or its molecular groups such as NH 3 , CH 3 , CH 4 ... For this reason, the study of the rotational behaviour of methyl groups in the solid state as a function of temperature is of great interest. With decreasing temperature, the rotations change from classical hoping to processes where quantum mechanical rotations become important. By quantum mechanical rotations, we mean the low-temperature counterpart, for with tunneling is the dominant mode of motion. However, the interpretation of tunnelling lines is critical when it is not straightforward to relate them to specific vibrational modes and particularly so when the molecule contains crystallographically inequivalent groups. The aim of this work is to interpret such spectra (obtained from inelastic neutron scattering) from structural data. The lack of structural knowledge at low temperatures, makes therefore a limited interpretation of the spectra obtained from polycrystalline samples. In a first step it is essential to solve crystalline structure of compounds by single crystal X-rays and neutron diffraction. Indeed X-ray diffraction is necessary to locate the skeleton (C, N, O and localised H atoms). Moreover neutron diffraction is the unique tool to precise the position of H atoms of methyl groups. The exam of the nuclear density of these protons the Fourier maps allows us to evaluate the crystal potential experienced by this rotor. Inelastic neutron scattering allows on single crystals allows the complete characterizations of quantum excitations (author)

  17. Biological activity of 2,3-Di (quinolyl-2)-6-methyl quinoxaline

    International Nuclear Information System (INIS)

    Ansar, N.; Kaban, S.; Ahmed, R.

    2003-01-01

    The biological activities of the nitrogen containing conjugated heterocyclic compounds are considerably used pharmaceutically as antiulcer, antimalarial, tubercluocidal and sedatives besides their uses as dyes in the textile industries, pesticides, stabilizers and inhibitors etc. 2.3-Di(quinolyl-2)-6-methyl quinoxaline was synthesized by condensation followed by ring closure reaction when 1,2-di(quinolyl-2)-1,2 ethanedione was treated with methyl and substituted o-phenylenediamine. (author)

  18. Biological activity of 2,3-Di (quinolyl-2)-6-methyl quinoxaline

    Energy Technology Data Exchange (ETDEWEB)

    Ansar, N [Adamjee Government Science College, Karachi (Pakistan). Dept. of Chemistry; Kaban, S [Yildiz Technical Univ., Istanbul (Turkey). Dept. of Chemistry; Ahmed, R [University of Karachi, Karachi (Pakistan). Dept. of Chemistry

    2003-06-01

    The biological activities of the nitrogen containing conjugated heterocyclic compounds are considerably used pharmaceutically as antiulcer, antimalarial, tubercluocidal and sedatives besides their uses as dyes in the textile industries, pesticides, stabilizers and inhibitors etc. 2.3-Di(quinolyl-2)-6-methyl quinoxaline was synthesized by condensation followed by ring closure reaction when 1,2-di(quinolyl-2)-1,2 ethanedione was treated with methyl and substituted o-phenylenediamine. (author)

  19. Coordination Polymers of N, Nʼ-di-(8-Hydroxyquinolinolyl- 5-methyl-N, N-diethyl-1,3-propane diamine (QEPD

    Directory of Open Access Journals (Sweden)

    Asha D. Patel

    2010-01-01

    Full Text Available Coordination polymers containing a novel bis(oxine bidentate ligand, namely N,Nʼ-di(8-hydroxyquinolinolyl-5-methyl-N,Nʼ-diethyl-1,3-propane diamine (QEPD have been prepared with the metal ions Zn(II, Cu(II, Ni(II, Co(II and Mn(II. The novel bis-(bidentate ligand was synthesized by condensation of 5-chloromethyl-8-hydroxyquinoline hydrochloride with N,Nʼ-diethyl-1,2- propane diamine in the presence of a base catalyses. All of these coordination polymers and the parent ligand were characterized by elemental analyses, IR spectral and diffuse reflectance spectral studies. The thermal stability and number- average molecular weights (Mn¯ of all of the coordination polymers were determined by thermogravimetric analyses and non-aqueous conductometric titrations, respectively. In addition, all of the coordination polymers have been characterized by their magnetic susceptibilities.

  20. Mechanistic Insights into the Organopolymerization of N-Methyl N-Carboxyanhydrides Mediated by N-Heterocyclic Carbenes

    KAUST Repository

    Falivene, Laura

    2016-10-04

    We report on a DFT investigation of initiation, propagation, and termination in the organopolymerization of N-methyl N-carboxyanhydrides toward cyclic poly(N-substituted glycine)s, promoted by N-heterocyclic carbenes (NHC). Calculations support the experimentally based hypothesis of two competing initiation pathways. The first leading to formation of a zwitterionic adduct by nucleophilic addition of the NHC to one of the carbonyl groups of monomer. The second via acid–base reactivity, starting with the NHC promoted abstraction of a proton from the methylene group of the monomer, leading to an ion-pair-type adduct, followed by nucleophilic attack of the adduct to a new monomer molecule. Chain elongation can proceed from both the initiation adducts via nucleophilic attack of the carbamate chain-end to a new monomer molecule via concerted elimination of CO2 from the carbamate chain-end. Energy barriers along all the considered termination pathways are remarkably higher that the energy barrier along the chain elongation pathways, consistent with the quasi-living experimental behavior. Analysis of the competing termination pathways suggests that the cyclic species determined via MALDI-TOF MS experiments consists of a zwitterionic species deriving from nucleophilic attack of the N atom of the carbamate chain-end to the C═O group bound to the NHC moiety.

  1. 2-{[2-Methyl-3-(2-methylphenyl-4-oxo-3,4-dihydroquinazolin-8-yl]oxy}acetonitrile

    Directory of Open Access Journals (Sweden)

    Adel S. El-Azab

    2012-07-01

    Full Text Available In the title compound, C18H15N3O2, the fused ring system is almost planar [the dihedral angle between the six-membered rings is 1.81 (6°]. The 2-tolyl ring is approximately orthogonal to this plane [dihedral angle = 83.03 (7°] as is the acetonitrile group [C—O—C—C torsion angle = 79.24 (14°] which is also syn to the methyl substituent of the tolyl group. In the crystal, supramolecular layers are formed in the bc plane mediated by C—H...O, C—H...N and C—H...π interactions. The tolyl group is disordered over two positions in a 0.852 (3:0.148 (3 ratio.

  2. Synthesis of [14C]-62514, a radiolabelled derivative of erythromycin A, via [2-14C]N,N-dimethylethylenediamine

    International Nuclear Information System (INIS)

    Surber, B.W.; Baker, W.R.; Seif, L.

    1991-01-01

    The synthesis of [ 14 C]A-62514, 11-deoxy-11[carboxy(2-dimethylamino-[1- 14 C]ethyl)amino]-6-0-methyl-e rythromycin A 11,12-(cyclic ester), was performed in five steps. The key intermediate, [2- 14 C]N,N-dimethylethyl-enediamine, was obtained in 80% yield by reacting Eschenmoser's salt with K 14 CN and reducing the resulting [1- 14 C]N,N-dimethylglycinonitrile with H 2 and Raney Ni in methanol and ammonium hydroxide. The final product was obtained 97% radiochemically pure in an overall radiochemical yield of 14%, with a specific activity of 39 mCi/mmol. (author)

  3. 2-Acetyl-amino-1,3,4,6-tetra-O-(tri-methyl-silyl)-2-de-oxy-α-d-gluco-pyran-ose.

    Science.gov (United States)

    Cheng, Zhao-Dong; Cui, Yan-Li; Mao, Jian-Wei

    2013-06-01

    The title compound, C20H47NO6Si4, was synthesized by per-O-tri-methyl-silylation of N-acetyl-d-glucosa-mine using chloro-tri-methyl-silane in the presence of hexa-methyl-disiloxane. The tri-methyl-silyl group and acetamido group are located on the same side of the pyran ring, showing an α-configuration glycoside. One of the tri-methyl-silyl groups is disordered over two orientations, with site-occupancy factors of 0.625 (9) and 0.375 (9). In the crystal, N-H⋯O hydrogen bonds link the mol-ecules into supra-molecular chains along the a-axis direction.

  4. [Specific features of 2-methyl hydroxybenzene and 3-methyl hydroxybenzene distribution in the organism of warm-blooded animals].

    Science.gov (United States)

    Shormanov, B K; Grishenko, V K; Astashkina, A P; Elizarova, M K

    2013-01-01

    The present work was designed to study the specific features of 2-methyl hydroxybezene and 3-methyl hydroxybenzene distribution after intragastric administration of these toxicants to warm-blooded animals (rats). They were detected in the unmetabolized form in the internal organs and blood of the animals. The levels of 2-methyl hydroxybezene were especially high in the stomach and blood whereas the maximum content of 3-methyl hydroxybenzene was found in brain, blood, small intestines of the poisoned rats.

  5. A Silsesquioxane Organically Modified with 4-Amino-5-(4-pyridyl-4H-1,2,4-triazole-3-thiol: Thermal Behavior and Its Electrochemical Detection of Sulfhydryl Compounds

    Directory of Open Access Journals (Sweden)

    D. R. Do Carmo

    2014-01-01

    Full Text Available The octakis(3-chloropropylsilsesquioxane (SS was organofunctionalized with 4-amino-5-4(pyridyl-4H-1,2,4-triazole-3-thiol. The product formed (SA was undergo another reactions in two steps, first with copper and so hexacyanoferrate (III to form CuHSA. The organofunctionalized silsesquioxane was characterized by the following techniques: scanning electron microscopy (SEM, Fourier transform infrared (FTIR, nuclear magnetic resonance (NMR in solid state, and thermogravimetric analysis in air and nitrogen atmosphere. The composite CuHSA was incorporated into a graphite paste electrode and the electrochemical behavior studies were conducted with cyclic voltammetry. The cyclic voltammogram of the modified graphite paste electrode with CuHSA showed one redox couple with formal potential Eθ′=0.75 V versus Ag/AgCl(sat (KCl 1.0 mol L−1; v = 20 mV s−1 attributed to the redox process Fe(II(CN6/Fe(III(CN6 of the binuclear complex formed. The redox couple presents an electrocatalytic response of sulfhydryl compounds such as n-acetylcysteine and l-cysteine. For determination of n-acetylcysteine and l-cysteine the modified graphite paste electrode showed a linear region in the concentration range of 2 to 20 mmol L−1. The modified electrode was chemically and electrochemically stable and showed good reproducibility.

  6. X-ray studies on piroxicam modifications

    International Nuclear Information System (INIS)

    Reck, G.; Bannier, G.; Hoehne, E.

    1988-01-01

    The anti-inflammatory drug piroxicam, 4-hydroxy-2-methyl-N-(2-pyridyl)2H-1,2-benzothiazine-3-car-boxamide-1,1-dioxide, crystallizes in three different forms, two anhydrates and one monohydrate. Crystal structure analyses of the monohydrate and one of the anhydrate were carried out by Bordner et al. and Kojic-Prodic et al., respectively. The results of the analysis of the third piroxicam modification and of an independently performed structure determination of the monohydrate are reported. Molecular structures and hydrogen bonding of all modifications are discussed. (author)

  7. Bis(2-ethylhexyl)-N,N-diethylcarbamoylmethyl phosphonate as a synergist in the extraction of trivalent lanthanides by 1-phenyl-3-methyl-4-trifluoroacetyl-pyrazolone-5

    International Nuclear Information System (INIS)

    Luxmi Varma, R.; Sujatha, S.; Reddy, M.L.P.; Prasada Rao, T.; Iyer, C.S.P.; Damodaran, A.D.

    1996-01-01

    Synergism in the extraction of trivalent lanthanides such as Nd. Eu and Lu has been investigated using mixtures of 1-phenyl-3-methyl-4-trifluoroacetyl-pyrazolone-5 (HPMTFP) and bis(2-ethylhexyl)-N,N-diethylcarbamoylmethyl phosphonate (CMP) in chloroform. Lanthanides are found to be extracted from 0.01 mol/dm 3 chloroacetate medium with HPMTFP as Ln(PMTFP) 3 or Ln(PMTFP) 3 . CMP in the absence or presence of CMP, respectively. The equilibrium constants of these synergistic species do not increase monotonically with atomic number but have a maximum at Eu. The addition of a synergist, CMP to the metal chelate system not only enhances the extraction efficiency but also improves the selectivities among these trivalent lanthanides. The IR results indicate that CMP acts as a bidentate ligand in these mixed-ligand systems. (orig.)

  8. Distribution of radiolabeled 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride in rat brain tumor: intraarterial versus intravenous administration

    International Nuclear Information System (INIS)

    Yamada, K.; Ushio, Y.; Hayakawa, T.; Arita, N.; Huang, T.Y.; Nagatani, M.; Yamada, N.; Mogami, H.

    1987-01-01

    To assess the rationale of intraarterial (i.a.) 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea chemotherapy, distribution of 14 C-labeled 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea in rat glioma was studied after i.a. or i.v. infusion. Immediately after infusion, the tumor located in the hemisphere of intracarotid infusion received 4.6-fold higher radioactivity than the tumor located contralaterally to intracarotid infusion and 2.8-fold higher radioactivity than i.v. infusion. The difference was kept up to 30 min after i.a. infusion. Autoradiographic observation indicated rather uniform distribution of the tracer in the central portion of i.a. infusion. However, in the periphery of i.a. infusion, distribution of the tracer was nonhomogenous. The results indicate that i.a. 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea chemotherapy is useful when the tumor has high blood flow and is located in the center of an infused area

  9. Anti-N-methyl-D-aspartate receptor encephalitis with an imaging-invisible ovarian teratoma: a case report.

    Science.gov (United States)

    Abdul-Rahman, Zainab M; Panegyres, Peter K; Roeck, Margareta; Hawkins, David; Bharath, Jude; Grolman, Paul; Neppe, Cliffe; Palmer, David

    2016-10-24

    Anti-N-methyl-D-aspartate receptor encephalitis is a recently discovered disease entity of paraneoplastic limbic encephalitis. It largely affects young women and is often associated with an ovarian teratoma. It is a serious yet treatable condition if diagnosed early. Its remedy involves immunotherapy and surgical removal of the teratoma of the ovaries. This case of anti-N-methyl-D-aspartate receptor encephalitis involves an early surgical intervention with bilateral oophorectomy, despite negative imaging evidence of a teratoma. A 25-year-old white woman with anti-N-methyl-D-aspartate receptor encephalitis presented with behavioral changes and seizures that were confirmed to be secondary to anti-N-methyl-D-aspartate receptor encephalitis. She required an admission to our intensive care unit for ventilator support and received a number of immunological therapies. Multiple imaging investigations showed no evidence of an ovarian teratoma; she had a bilateral oophorectomy 29 days after admission. Ovarian histology confirmed the presence of a teratoma with neuronal cells. A few days after the operation she began to show signs of improvement and, apart from mild short-term memory loss, she returned to normal function. Our patient is an example of teratoma-associated anti-N-methyl-D-aspartate receptor encephalitis, in which the teratoma was identified only microscopically. Her case highlights that even with negative imaging evidence of a teratoma, ovarian pathology should still be considered and explored.

  10. (Dimethylformamide-κO(2-hydroxybenzoato-κ2O1,O1′[tris(1-methyl-1H-benzimidazol-2-ylmethyl-κN3amine-κN]manganese(II perchlorate dimethylformamide monosolvate

    Directory of Open Access Journals (Sweden)

    Baoliang Qi

    2010-10-01

    Full Text Available In the title complex, [Mn(C7H5O3(C27H27N7(C3H7NO]ClO4·C3H7NO, the MnII ion is coordinated in a slightly distorted monocapped trigonal-prismatic geometry. The tris(1-methyl-1H-benzimidazol-2-ylmethylamine (Mentb ligand coordinates in a tetradentate mode and the coordination is completed by a bis-chelating salicylate ligand and a dimethylformamide ligand. The hydroxy group and the ortho H atoms of the salicylate ligand were refined as disordered over two sites with occupancies of 0.581 (8 and 0.419 (8. Both disorder components of the hydroxy group form intramolecular O—H...O hydrogen bonds.

  11. Practical synthesis of aryl-2-methyl-3-butyn-2-ols from aryl bromides via conventional and decarboxylative copper-free Sonogashira coupling reactions

    Directory of Open Access Journals (Sweden)

    Andrea Caporale

    2014-02-01

    Full Text Available Two efficient protocols for the palladium-catalyzed synthesis of aryl-2-methyl-3-butyn-2-ols from aryl bromides in the absence of copper were developed. A simple catalytic system consisting of Pd(OAc2 and P(p-tol3 using DBU as the base and THF as the solvent was found to be highly effective for the coupling reaction of 2-methyl-3-butyn-2-ol (4 with a wide range of aryl bromides in good to excellent yields. Analogously, the synthesis of aryl-2-methyl-3-butyn-2-ols was performed also through the decarboxylative coupling reaction of 4-hydroxy-4-methyl-2-pentynoic acid with aryl bromides, using a catalyst containing Pd(OAc2 in combination with SPhos or XPhos in the presence of tetra-n-butylammonium fluoride (TBAF as the base and THF as the solvent. Therefore, new efficient approaches to the synthesis of terminal acetylenes from widely available aryl bromides rather than expensive iodides and using 4 or propiolic acid rather than TMS-acetylene as inexpensive alkyne sources are described.

  12. Pulse radiolysis study on free radical scavenger edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one). 2: A comparative study on edaravone derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Hata, Kuniki; Katsumura, Yosuke [Tokyo Univ., School of Engineering, Tokyo (Japan); Lin, M; Yamashita, Shinichi [Japan Atomic Energy Agency, Advanced Science Research Center, Tokai, Ibaraki (Japan); Muroya, Yusa [Tokyo Univ., Nuclear Professional School, Tokai, Ibaraki (Japan); Haiying, Fu [Chinese Academy of Sciences, Shanghai (China); Nakagawa, Hidehiko [Nagoya City Univ., Graduate School of Pharmaceutical Sciences, Nagoya, Aichi (Japan)

    2011-01-15

    A comparative study using the pulse radiolysis technique was carried out to investigate transient absorption spectra and rate constants for the reactions of OH radical and N{sub 3} radical with edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) and its four analogue compounds, 1,3-dimethyl-2-pyrazolin-5-one, 3-methyl-1-(pyridin-2-yl)-2-pyrazolin-5-one, 1-phenyl-3-trifluoromethyl-2-pyrazolin-5-one and 1-(4-chlorophenyl)-3-methyl-2-pyrazolin-5-one. The results showed that, unlike reaction mechanisms previously proposed, the phenyl group of edaravone played an important role in the reaction with OH radical and OH adducts to the phenyl group were formed. Quantum chemical calculations also strongly supported this attribution and suggested that the most favorable site for attacks by OH radical is the ortho position of the phenyl group. Moreover, the rate constants for the reactions of edaravone and its analogues towards OH radical and N{sub 3} radical were about 8.0 x 10{sup 9}, and 4.0 x 10{sup 9} dm{sup 3} mol{sup -1} s{sup -1}, respectively. Edaravone displayed higher reactivity compared to the others, in contrast to a previous report in which 3-methyl-1-(pyridin-2-yl)-2-pyrazolin-5-one showed the highest reactivity towards Hydroxyl radical OH. (author)

  13. Anesthesia in anti-N-methyl-D-aspartate receptor encephalitis - is general anesthesia a requisite? A case report

    Directory of Open Access Journals (Sweden)

    Sook Hui Chaw

    Full Text Available Abstract Anti-N-methyl-D-aspartate receptor encephalitis is a recently described neurological disorder and an increasingly recognized cause of psychosis, movement disorders and autonomic dysfunction. We report 20-year-old Chinese female who presented with generalized tonic-clonic seizures, recent memory loss, visual hallucinations and abnormal behavior. Anti-N-methyl-D-aspartate receptor encephalitis was diagnosed and a computed tomography scan of abdomen reviewed a left adnexal tumor. We describe the first such case report of a patient with anti-N-methyl-D-aspartate receptor encephalitis who was given a bilateral transversus abdominis plane block as the sole anesthetic for removal of ovarian tumor. We also discuss the anesthetic issues associated with anti-N-methyl-D-aspartate receptor encephalitis. As discovery of tumor and its removal is the focus of initial treatment in this group of patients, anesthetists will encounter more such cases in the near future.

  14. 4-Aminobenzoic acid–1,2-bis(4-pyridylethane (2/1

    Directory of Open Access Journals (Sweden)

    Fwu Ming Shen

    2010-07-01

    Full Text Available In the title compound, C12H12N2·2C7H7NO2, the 4-aminobenzoic acid molecules are linked by O—H...N hydrogen bonds to 1,2-bis(4-pyridylethane, forming linear hydrogen bonded chains parallel to [2overline{1}1]. The structure exhibits a hydrogen-bonding network involving COOH...N(pyridyl and amine and carboxylic N—H... O interactions. In addition, π–π stacking interactions [centroid–centroid distance = 3.8622 (14 Å] are also present.

  15. Effects of combined exposure of F344 rats to inhaled Plutonium-239 dioxide and a chemical carcinogen (NNK)

    Energy Technology Data Exchange (ETDEWEB)

    Lundgren, D.L.; Carlton, W.W. [Purdue Univ., Lafayette, IN (United States); Griffith, W.C. [and others

    1995-12-01

    Workers in nuclear weapons facilities have a significant potential for exposure to chemical carcinogens and to radiation from external sources or from internally deposited radionuclides such as {sup 239}Pu. Although the carcinogenic effects of inhaled {sup 239}Pu and many chemicals have been studied individually, very little information is available on their combined effects. One chemical carcinogen that workers could be exposed to via tobacco smoke is the tobacco-specific nitrosamine 4-(N-methyl-n-nitrosamino)-1-(3-pyridyl)-1(3-pyridyl)-1-butanone (NNK), a product of tobacco curing and the pyrolysis of nicotine in tobacco. NNK causes lung tumors in rats, regardless of the route of administration and to a lesser extent liver, nasal, and pancreatic tumors. From the results presented, it can be concluded that exposure to a chemical carcinogen (NNK) in combination with {alpha}-particle radiation from inhaled {sup 239}PuO{sub 2} acts in, at best, an additive manner in inducing lung cancer in rats.

  16. Comparative Studies with N-Methyl-2-Pyrrolidone and Furfural As Solvents for Extraction of Lube Distillates Etude comparative de deux solvants, la n-methyl-2 pyrrolidone et le furfural, pour l'extraction de distillats pour huiles lubrifiantes

    OpenAIRE

    Krishna R.; Singh H.; Kishore K.; Choudhary G. S.; Kaushik R. S.

    2006-01-01

    Solvent extraction of spindle raw lube distillate from Oman crude using n-methyl pyrrolidone (NMP) containing 1. 5wt. % water has been studied using a six-stage all-glass mixer-settler. Results of three operating temperatures with NMP are reported. A 65-55°C extraction temperature appears to be most appropriate for this stock. Data obtained at this temperature have been compared with those for furfural on the basis of phase boundary curves, extraction and lube refining indices and selectivity...

  17. Two novel penetrating coordination polymers based on flexible S-containing dicarboxylate acid with sensing properties towards Fe3+ and Cr2O72- ions

    Science.gov (United States)

    Chen, Zhiwei; Mi, Xiuna; Wang, Suna; Lu, Jing; Li, Yunwu; Li, Dacheng; Dou, Jianmin

    2018-05-01

    Two new coordination polymers (CPs), namely, {[Zn(L)(bpp)]·DMF}n (1) and {[Zn(L)(bpe)]·DMF}n (2) (L = 2,2'-[benzene-1,3-diylbis(methanediylsulfanediyl)]dibenzoic acid, bpp= 1,3-bis(4-pyridyl)propane, bpe = 1,2-Bis(4-pyridyl)ethylene, DMF = N,N-Dimethylformamide), have been solvothermally synthesized and fully characterized. Complex 1 displays a 2D→2D three-fold"false" interpenetrating structure while complex 2 possesses a novel 3-D 4-connected structure with fascinating self-penetrating moieties. The luminescence studies reveal that these complexes exhibited excellent selectivity for Fe3+ and Cr2O72- ions in DMF. The sensing mechanism was investigated through PXRD, XPS , EDS mapping measurements, and discussed in details.

  18. Proposal of 5-methoxy-N-methyl-N-isopropyltryptamine consumption biomarkers through identification of in vivo metabolites from mice.

    Science.gov (United States)

    Fabregat-Safont, D; Barneo-Muñoz, M; Martinez-Garcia, F; Sancho, J V; Hernández, F; Ibáñez, M

    2017-07-28

    New psychoactive substances (NPS) are a new breed of synthetically produced substances designed to mimic the effects of traditional illegal drugs. Synthetic cannabinoids and synthetic cathinones are the two most common groups, which try to mimic the effects of the natural compounds 9 Δ-tetrahydrocannabinol and cathinone, respectively. Similarly, synthetic tryptamines are designer compounds which are based on the compounds psilocin, N,N-dimethyltryptamine and 5-methoxy-N,N-dimethyltryptamine found in some mushrooms. One of the most important tryptamine compounds found in seizures is 5-methoxy-N,N-diisopropyltryptamine, which has been placed as controlled substance in USA and some European countries. The control of this compound has promoted the rising of another tryptamine, the 5-methoxy-N-methyl-N-isopropyltryptamine, which at the time of writing this article has not been banned yet. So, it is undeniable that this new substance should be monitored. 5-methoxy-N-methyl-N-isopropyltryptamine has been reported by the Spanish Early Warning System and detected in our laboratory in two pill samples purchased in a local smart shop. This has promoted the need of stablishing consumption markers for this compound in consumers' urine. In the present work, the metabolism and pharmacokinetic of 5-methoxy-N-methyl-N-isopropyltryptamine has been studied by an in vivo approach, using adult male mice of the inbred strain C57BLJ/6. The use of ultra-high performance liquid chromatography coupled to high resolution mass spectrometry allowed the identification of four metabolites. After the pharmacokinetic study in serum and urine, the O-demethylated metabolite and the non-metabolised parent compound are proposed as consumption markers in hydrolysed urine. Data reported in this work will help hospitals and forensic laboratories to monitor the consumption and potential intoxication cases related to this tryptamine. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Synthesis, molecular structure, spectroscopic properties and stability of (Z)-N-methyl-C-2,4,6-trimethylphenylnitrone

    Science.gov (United States)

    Lasri, Jamal; Ismail, Ali I.; Haukka, Matti; Soliman, Saied M.

    2015-02-01

    New N-methyl-C-2,4,6-trimethylphenylnitrone 1 has been synthesized starting from N-methylhydroxylamine and mesitaldehyde. The product was fully characterized using different spectroscopic techniques; FTIR, NMR, UV-Vis, high resolution mass spectrometry and X-ray diffraction. The relative stability and percent of population of its two possible isomers (E and Z) were calculated using the B3LYP/6-311++G(d,p) method in gas phase and in solution. In agreement with the X-ray results, it was found that Z-isomer is the most stable one in both gas phase and solution. The molecular geometry, vibrational frequencies, gauge-including atomic orbital (GIAO), and chemical shift values were also calculated using the same level of theory. The TD-DFT results of the studied nitrone predicted a π-π∗ transition band at 285.1 nm (fosc = 0.3543) in the gas phase. The rest of the spectral bands undergo either hyperchromic or hypsochromic shifts in the presence of solvent. Polarizability and HOMO-LUMO gap values were used to predict the nonlinear optical properties (NLO) of the studied compound. NBO analysis has been used to determine the most accurate Lewis structure of the studied molecule.

  20. Crystal structure of 3-methyl-2,6-bis(4-methyl-1,3-thiazol-5-ylpiperidin-4-one

    Directory of Open Access Journals (Sweden)

    A. Manimaran

    2014-09-01

    Full Text Available In the title compound, C14H17N3OS2, the central piperidinone ring adopts a chair conformation and the thiazole rings are inclined to its mean plane by 80.16 (12 and 67.15 (12°. The O atom and methyl group C atom deviate significantly from the mean plane of the central piperidinone ring, by 0.8138 (2 and 0.3175 (2 Å, respectively. The dihedral angle between the thiazole rings is 51.88 (13°. In the crystal, molecules are linked via C—H...O hydrogen bonds, forming zigzag C(10 chains running parallel to [001].

  1. New optically active and thermally stable poly(amide-imide)s containing N,N'-(Bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic)-bis-L-alanine and aromatic diamines: synthesis and characterization

    International Nuclear Information System (INIS)

    Faghihi, Khalil; Absalar, Morteza; Hajibeygi, Mohsen

    2009-01-01

    Five new optically active poly(amide-imide)s (PAIs) 6a-e were prepared by direct polycondensation reaction of the newly synthesized N,N'-(bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetra carboxylic)-bis-L-alanine 4 with various aromatic diamines 5a-e using polar aprotic solvents such as N-methyl-2-pyrrolidone (NMP). In this technique triphenyl phosphite (TPP) and pyridine were used as condensing agents to form poly(amide-imide)s through the N-phosphonium salts of pyridine. All of the polymers were obtained in quantitative yields with inherent viscosities between 0.29-0.46 dL g -1 and were highly soluble in polar aprotic solvents such as N,N-dimethyl acetamide (DMAc), N,N-dimethyl formamide (DMF), dimethyl sulfoxide (DMSO), N-methyl- 2-pyrrolidone (NMP) and solvents such as sulfuric acid. They were fully characterized by means of 1 H NMR, FTIR spectroscopy, elemental analyses, inherent viscosity, solubility test, specific rotation and thermal properties of these polymers were investigated using thermogravimetric analysis techniques (TGA and DTG). (author)

  2. [Anesthesia in anti-N-methyl-d-aspartate receptor encephalitis - is general anesthesia a requisite? A case report].

    Science.gov (United States)

    Chaw, Sook Hui; Foo, Li Lian; Chan, Lucy; Wong, Kang Kwong; Abdullah, Suhailah; Lim, Boon Kiong

    Anti-N-methyl-d-aspartate receptor encephalitis is a recently described neurological disorder and an increasingly recognized cause of psychosis, movement disorders and autonomic dysfunction. We report 20-year-old Chinese female who presented with generalized tonic-clonic seizures, recent memory loss, visual hallucinations and abnormal behavior. Anti-N-methyl-d-aspartate receptor encephalitis was diagnosed and a computed tomography scan of abdomen reviewed a left adnexal tumor. We describe the first such case report of a patient with anti-N-methyl-d-aspartate receptor encephalitis who was given a bilateral transversus abdominis plane block as the sole anesthetic for removal of ovarian tumor. We also discuss the anesthetic issues associated with anti-N-methyl-d-aspartate receptor encephalitis. As discovery of tumor and its removal is the focus of initial treatment in this group of patients, anesthetists will encounter more such cases in the near future. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

  3. Rapid Quantification of N-Methyl-2-pyrrolidone in Polymer Matrices by Thermal Desorption-GC/MS.

    Science.gov (United States)

    Kim, Young-Min; Kim, Jae Woo; Moon, Hye Mi; Lee, Min-Jin; Hosaka, Akihiko; Watanabe, Atsushi; Teramae, Norio; Park, Young-Kwon; Myung, Seung-Woon

    2017-01-01

    Analysis of a residual solvent in polymeric materials has become an important issue due to the increased regulations and standards for its use. N-Methyl-2-pyrrolidone (NMP) is a solvent widely used in many industries and restricted as one of the chemicals under EU REACH regulations due to its potential harmful effects. In this study, thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS) is applied for the quantitative analysis of NMP with the use of a polymer-coated sample cup. By using the polymer-coated sample cup, the vaporization of NMP was prevented during waiting time before TD-GC/MS analysis. The calibration curve for the TD method showed good linearity (correlation coefficient, r 2 = 0.9998) and precision values (below 5.3% RSD). NMP recovery rates in different polymer matrices (PS, PMMA and PVC) were in the range of 98.8 to 106.6% with RSD values below 5.0%. The quantification result (600 mg NMP/kg PVC) for the blind NMP carrying sample in a PVC matrix by TD-GC/MS was higher than that (532 mg NMP/kg PVC) by solvent extraction-GC/MS method.

  4. Laboratory and Field Studies of Poly(2,5-bis(N-methyl-N-hexylaminophenylene vinylene (BAM-PPV: A Potential Wash Primer Replacement for Army Military Vehicles

    Directory of Open Access Journals (Sweden)

    Peter Zarras

    2014-09-01

    Full Text Available In this study, an electroactive polymer (EAP, poly(2,5-bis(N-methyl-N- hexylaminophenylene vinylene (BAM-PPV, was tested as an alternative to current hexavalent chromium (Cr(VI-based Army wash primers. BAM-PPV was tested in both laboratory and field studies to determine its adhesive and corrosion-inhibiting properties when applied to steel and aluminum alloys. The Army Research Laboratory (ARL tests showed that BAM-PPV combined with an epoxy primer and the Army chemical agent-resistant coating (CARC topcoat met Army performance requirements for military coatings. After successful laboratory testing, the BAM-PPV was then field tested for one year at the Aberdeen Test Center (ATC. This field testing showed that BAM-PPV incorporated into the Army military coating survived with no delamination of the coating and only minor corrosion on the chip sites.

  5. Hydrothermal oxidation of an epoxy resin through the study of two model molecules: N-methyl-acetamide and N,N-di[1(phenoxy)2-hydroxy propyl-3] propyl-amine

    International Nuclear Information System (INIS)

    Moutonnet-Fromonteil, C.

    2000-01-01

    The study consists in choosing and developing a technology to realize damage experiments of an epoxy resin which is used as coating of embedded nuclear samples. Hydrothermal oxidation is the chosen method. We first identified the chemical composition of the epoxy resin. Then we studied hydrolysis and oxidation of a molecule which contains a function of the epoxy network: N-methyl-acetamide. The comparison between our results and those already existing allowed to validate this degradation method. In a second part, we studied a model molecule of the polymer network: N, N-di[1(phenoxy)2-hydroxy propyl-3] propyl-amine. The hydrolysis temperatures are relatively high: the compound is totally destroyed at 300 deg C. Its oxidation leads to the formation of acetic acid from 220 deg C. In the third study, we determined the best experimental conditions to destroy the epoxy resin. Experiments were performed at different temperatures between 200 deg C and 410 deg C. The degradation rates are classically defined by amounts of constituents in liquid and gaseous phases. (author)

  6. Synthesis, spectral, thermal studies and electrical conductivity of Co (II) and Ni (II) complexes 3-[4-dimethylaminophenyl]-1-(2-pyridyl) prop-2-en-1-one (DMAPP)

    Energy Technology Data Exchange (ETDEWEB)

    Gaber, Mohamed, E-mail: abuelazm@yahoo.com [Chemistry Department, Faculty of Science, Tanta University, 31527 Tanta (Egypt); Al-Daly, Samy; Fayed, Tarek [Chemistry Department, Faculty of Science, Tanta University, 31527 Tanta (Egypt); El-Sayed, Yousif [Department of Chemistry, Faculty of Science, Tanta University, Tanta (Egypt)

    2015-01-15

    Co(II) and Ni(II) complexes of 3-[4-dimethylaminophenyl]-1-(2-pyridyl)prop-2-en-1-one have been prepared and characterized on the basis of elemental analyses, molar conductance, magnetic susceptibility measurements, IR, electronic spectra as well as thermal studies. The magnetic and spectral studies suggested the octahedral geometry for Co(II) and Ni(II) complexes. The kinetic parameters of the thermal decomposition stages have been evaluated using Coats–Redfern method. The electrical conductivity of the titled ligand and its Co(II) complexes was studied. The effects of different alcoholic solvents, pH and temperature on the complexation formation were considered. Also, the effect of Co(II) and Ni(II) ions on the emission spectrum of the free DMAPP was assigned. The stoichiometry of the metal complexes, the conditional formation constant, free energy, Beer{sup '}s law, molar extinction coefficient as well as specific absorptivity were evaluated. The ability of using the titled ligand as metalochromic indicator in complexometric titration was studied.

  7. In silico identification of BIM-1 (2-methyl-1H-indol-3-yl) as a potential ...

    African Journals Online (AJOL)

    In silico identification of BIM-1 (2-methyl-1H-indol-3-yl) as a potential therapeutic agent against elevated protein kinase C beta associated diseases. U Saeed, N Nawaz, Y Waheed, N Chaudry, HT Bhatti, S Urooj, H Waheed, M Ashraf, UHK Naizi ...

  8. Characterization of the anti tumoral activity of the thiosemicarbazones derived from N(4)-methyl-tolyl-2acetylpyridine And 2-pyridinoformamide and its metal complex: evaluation of the radiopharmaceutical potential

    International Nuclear Information System (INIS)

    Silva, Paulo Roberto Ornelas da

    2008-01-01

    Thiosemicarbazones have attracted great pharmacological interest because of their biological properties, such as cytotoxic activity against multiple strains of human tumors. The most studied compounds are pyridine-based because of their resemblance to pyridoxal metabolites that attach to co-enzyme B 6 -dependant enzymes. This work aimed the characterization of the anti tumoral effect of N(4)-methyl-tolyl-2-acetylpyridine and 2-pyridinoformamide-derived thiosemicarbazones and the development of a radiopharmaceutical based on a thiosemicarbazone metal complex for positron emission tomography. In the first phase of this study were synthesized twenty-one thiosemicarbazones, derived from N(4)methyl-2 acetylpyridine and 2-pyridine formamide, as well as their metal complexes (Sn, Ga and Cu). Their cytotoxic potential were evaluated against brain and breast tumor cells in vitro. Our results showed all of them presented powerful cytotoxic and antiproliferative activities against glioblastoma multiform and breast adenocarcinoma at very low concentrations (nanomolar range). Morphological alterations characteristic of apoptosis, such as cell shrinkage, chromatin condensation were observed. Copper chloride was used as control and has presented IC50 at millimolar range suggesting that copper complexation with thiosemicarbazone significantly increases (more than 1 million) the anti tumoral effect of this metal. Due to the potent anti tumoral activity of N(4)-methyl-tolyl-2-acetylpyridine derived thiosemicarbazones and the excellent properties of 64 Cu (T 1/2 = 12.7 hours, β + , β - , and EC decay), at the second part for this work it was developed a new imaging agent (radiopharmaceutical) for tumor detection by positron emission tomography (PET). The radiopharmaceuticals were produced in the nuclear reactor TRIGA-IPR-R1 from CDTN, via neutron capture reaction 63 Cu (n,γ) 64 Cu, of the copper complex N(4)-ortho-toluyl-2-acetylpyridine thiosemicarbazone (Culac). The induced

  9. The preference of tryptophan for membrane interfaces: insights from N-methylation of tryptophans in gramicidin channels.

    Science.gov (United States)

    Sun, Haiyan; Greathouse, Denise V; Andersen, Olaf S; Koeppe, Roger E

    2008-08-08

    To better understand the structural and functional roles of tryptophan at the membrane/water interface in membrane proteins, we examined the structural and functional consequences of Trp --> 1-methyl-tryptophan substitutions in membrane-spanning gramicidin A channels. Gramicidin A channels are miniproteins that are anchored to the interface by four Trps near the C terminus of each subunit in a membrane-spanning dimer. We masked the hydrogen bonding ability of individual or multiple Trps by 1-methylation of the indole ring and examined the structural and functional changes using circular dichroism spectroscopy, size exclusion chromatography, solid state (2)H NMR spectroscopy, and single channel analysis. N-Methylation causes distinct changes in the subunit conformational preference, channel-forming propensity, single channel conductance and lifetime, and average indole ring orientations within the membrane-spanning channels. The extent of the local ring dynamic wobble does not increase, and may decrease slightly, when the indole NH is replaced by the non-hydrogen-bonding and more bulky and hydrophobic N-CH(3) group. The changes in conformational preference, which are associated with a shift in the distribution of the aromatic residues across the bilayer, are similar to those observed previously with Trp --> Phe substitutions. We conclude that indole N-H hydrogen bonding is of major importance for the folding of gramicidin channels. The changes in ion permeability, however, are quite different for Trp --> Phe and Trp --> 1-methyl-tryptophan substitutions, indicating that the indole dipole moment and perhaps also ring size and are important for ion permeation through these channels.

  10. Synthesis and characterization of a thermo-sensitive poly( N-methyl acryloylglycine methyl ester) used as a drug release carrier

    Science.gov (United States)

    Deng, Kui-Lin; Zhong, Hai-Bin; Jiao, Yi-Suo; Fan, Ting; Qiao, Xiao; Zhang, Peng-Fei; Ren, Xiao-Bo

    2010-06-01

    In this article, poly( N-methyl acryloylglycine methyl ester) (PNMAME) was prepared as a novel thermosensitive material with a lower critical solution temperature (LCST) at around 49.5°C. The chemical structures of the monomer NMAME and PNMAME were characterized by 1H NMR and IR measurements. The LCST was investigated systematically as a function of PNMAME concentration, inorganic salt solution and pH value. The results indicated that LCST of PNMAME was obviously dependent on PNMAME concentration and pH. The LCST was increased with a decrease in pH value and PNMAME concentration. To obtain a thermo-sensitive hydrogel with the phase transition temperature close to human body temperature, the copolymerization was conducted between NMAME and N-acryloylglycine ethyl ester (NAGEE). The release behavior of caffeine was evaluated at different temperatures and contents of cross-linkers ( N, N-methylenebis(acrylamide) (NMBA)). The increase of cross-linker content led to a decrease in the release rate of caffeine due to higher crossing density in the hydrogel network. In addition, a faster release of caffeine from the hydrogel with 3% NMBA at 37°C was found in contrast to that at 18°C.

  11. Synthesis, Characterization and Photophysical Properties of Pyridine-Carbazole Acrylonitrile Derivatives

    Science.gov (United States)

    Pérez-Gutiérrez, Enrique; Percino, M. Judith; Chapela, Víctor M.; Cerón, Margarita; Maldonado, José Luis; Ramos-Ortiz, Gabriel

    2011-01-01

    We synthesized three novel highly fluorescent compounds, 2-(2’-pyridyl)-3-(N-ethyl-(3’-carbazolyl))acrylonitrile, 2-(3”-pyridyl)-3-(N-ethyl-(3’-carbazolyl))acrylonitrile, and 2-(4-pyridyl)-3-(N-ethyl-(3’-carbazolyl))acrylonitrile by Knoevenagel condensation. The first two were synthesized without solvent in the presence of piperidine as a catalyst; the third was synthesized without a catalyst and with N,N-dimethylformamide as a solvent. In solution, the molar absorption coefficients showed absorptions at 380, 378, and 396 nm, respectively; in solid state, absorptions were at 398, 390, and 442 nm, respectively. The fluorescence emission was at 540, 540 and 604 nm, respectively, the 2-(4-pyridyl)-3-(N-ethyl-(3’-carbazolyl))acrylonitrile showed a red shift in the emission of 64 nm compared to the other two compounds. The fluorescence quantum yield for the compounds in powder form showed values of 0.05, 0.14, and 0.006, respectively; compared with the value measured for the Alq3 reference, 2-(3”-pyridyl)-3-(N-ethyl-(3’-carbazolyl))acrylonitrile had a lightly higher value. The third harmonic generation measurement for 2-(2’-pyridyl)-3-(N-ethyl-(3’-carbazolyl))acrylonitrile yielded a χ(3) value of 5.5 × 10−12 esu, similar to that reported for commercial polymers. PMID:28880006

  12. Synthesis, Characterization and Photophysical Properties of Pyridine-Carbazole Acrylonitrile Derivatives

    Directory of Open Access Journals (Sweden)

    Gabriel Ramos-Ortiz

    2011-03-01

    Full Text Available We synthesized three novel highly fluorescent compounds, 2-(2’-pyridyl-3-(N-ethyl-(3’-carbazolylacrylonitrile, 2-(3”-pyridyl-3-(N-ethyl-(3’-carbazolylacrylonitrile, and 2-(4-pyridyl-3-(N-ethyl-(3’-carbazolylacrylonitrile by Knoevenagel condensation. The first two were synthesized without solvent in the presence of piperidine as a catalyst; the third was synthesized without a catalyst and with N,N-dimethylformamide as a solvent. In solution, the molar absorption coefficients showed absorptions at 380, 378, and 396 nm, respectively; in solid state, absorptions were at 398, 390, and 442 nm, respectively. The fluorescence emission was at 540, 540 and 604 nm, respectively, the 2-(4-pyridyl-3-(N-ethyl-(3’-carbazolylacrylonitrile showed a red shift in the emission of 64 nm compared to the other two compounds. The fluorescence quantum yield for the compounds in powder form showed values of 0.05, 0.14, and 0.006, respectively; compared with the value measured for the Alq3 reference, 2-(3”-pyridyl-3-(N-ethyl-(3’-carbazolylacrylonitrile had a lightly higher value. The third harmonic generation measurement for 2-(2’-pyridyl-3-(N-ethyl-(3’-carbazolylacrylonitrile yielded a χ(3 value of 5.5 × 10−12 esu, similar to that reported for commercial polymers.

  13. Di-?-cyanido-tetra?cyanido(5,5,7,12,12,14-hexa?methyl-1,4,8,11-tetra?aza?cyclo?tetra?decane)[N-(quinolin-8-yl)quinoline-2-carboxamidato]diiron(III)nickel(II) 2.07-hydrate

    OpenAIRE

    Yang, Yuqi; Zhou, Hongbo; Shen, Xiaoping

    2013-01-01

    The asymmetric unit of the title complex, [Fe2Ni(C19H12N3O)2(CN)6(C16H36N4)]?2.07H2O, contains one [Fe(qcq)(CN)3]? anion, half a [Ni(teta)]2+ cation and two partially occupied inter?stitial water mol?ecules [qcq? is the N-(quinolin-8-yl)quinoline-2-carboxamidate anion and teta is 5,5,7,12,12,14-hexa?methyl-1,4,8,11-tetra?aza?cyclo?tetra?deca?ne]. In the complex mol?ecule, two [Fe(qcq)(CN)3]? anions additionally coordinate the central [Ni(teta)]2+ cation through cyanide groups in a trans mode,...

  14. DNA methylation of the IGF2/H19 imprinting control region and adiposity distribution in young adults

    Directory of Open Access Journals (Sweden)

    Huang Rae-Chi

    2012-11-01

    Full Text Available Abstract Background The insulin-like growth factor 2 (IGF2 and H19 imprinted genes control growth and body composition. Adverse in-utero environments have been associated with obesity-related diseases and linked with altered DNA methylation at the IGF2/H19 locus. Postnatally, methylation at the IGF2/H19 imprinting control region (ICR has been linked with cerebellum weight. We aimed to investigate whether decreased IGF2/H19 ICR methylation is associated with decreased birth and childhood anthropometry and increased contemporaneous adiposity. DNA methylation in peripheral blood (n = 315 at 17 years old was measured at 12 cytosine-phosphate-guanine sites (CpGs, analysed as Sequenom MassARRAY EpiTYPER units within the IGF2/H19 ICR. Birth size, childhood head circumference (HC at six time-points and anthropometry at age 17 years were measured. DNA methylation was investigated for its association with anthropometry using linear regression. Results The principal component of IGF2/H19 ICR DNA methylation (representing mean methylation across all CpG units positively correlated with skin fold thickness (at four CpG units (P-values between 0.04 to 0.001 and subcutaneous adiposity (P = 0.023 at age 17, but not with weight, height, BMI, waist circumference or visceral adiposity. IGF2/H19 methylation did not associate with birth weight, length or HC, but CpG unit 13 to 14 methylation was negatively associated with HC between 1 and 10 years. β-coefficients of four out of five remaining CpG units also estimated lower methylation with increasing childhood HC. Conclusions As greater IGF2/H19 methylation was associated with greater subcutaneous fat measures, but not overall, visceral or central adiposity, we hypothesize that obesogenic pressures in youth result in excess fat being preferentially stored in peripheral fat depots via the IGF2/H19 domain. Secondly, as IGF2/H19 methylation was not associated with birth size but negatively with early childhood HC, we

  15. New optically active and thermally stable poly(amide-imide)s containing N,N'-(Bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic)-bis-L-alanine and aromatic diamines: synthesis and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Faghihi, Khalil; Absalar, Morteza; Hajibeygi, Mohsen [Arak University (Iran, Islamic Republic of). Faculty of Science. Organic Polymer Chemistry Research Lab.

    2009-07-01

    Five new optically active poly(amide-imide)s (PAIs) 6a-e were prepared by direct polycondensation reaction of the newly synthesized N,N'-(bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetra carboxylic)-bis-L-alanine 4 with various aromatic diamines 5a-e using polar aprotic solvents such as N-methyl-2-pyrrolidone (NMP). In this technique triphenyl phosphite (TPP) and pyridine were used as condensing agents to form poly(amide-imide)s through the N-phosphonium salts of pyridine. All of the polymers were obtained in quantitative yields with inherent viscosities between 0.29-0.46 dL g{sup -1} and were highly soluble in polar aprotic solvents such as N,N-dimethyl acetamide (DMAc), N,N-dimethyl formamide (DMF), dimethyl sulfoxide (DMSO), N-methyl- 2-pyrrolidone (NMP) and solvents such as sulfuric acid. They were fully characterized by means of {sup 1}H NMR, FTIR spectroscopy, elemental analyses, inherent viscosity, solubility test, specific rotation and thermal properties of these polymers were investigated using thermogravimetric analysis techniques (TGA and DTG). (author)

  16. Solution-phase synthesis of a hindered N-methylated tetrapeptide using Bts-protected amino acid chlorides: efficient coupling and methylation steps allow purification by extraction.

    Science.gov (United States)

    Vedejs, E; Kongkittingam, C

    2000-04-21

    N-Benzothiazole-2-sulfonyl (Bts)-protected amino acid chlorides were used to prepare the hindered cyclosporin 8-11 tetrapeptide subunit 1. The synthesis was performed via 3a and the deprotected amines 5a, 13, and 19, including three repeated cycles involving N-methylation using iodomethane/potassium carbonate, deprotection of the Bts group, and N-acylation with a N-Bts-amino acid chloride such as 9b or 9c. Among three Bts cleavage methods compared (H3PO2/THF; NaBH4/EtOH; PhSH/K2CO3), the third gave somewhat higher overall yields. N-Acylation of 5a with the Bts-protected N-methylamino acid chloride 10b followed by deprotection was also highly efficient and could be used as an alternative route to 11. Each of the deprotected amines was isolated without chromatography using simple extraction methods to remove neutral byproducts. The tetrapeptide 1 was obtained in analytically pure form as the monohydrate.

  17. Innate immune restriction and antagonism of viral RNA lacking 2'-O methylation

    Energy Technology Data Exchange (ETDEWEB)

    Hyde, Jennifer L. [Departments of Medicine, Washington University School of Medicine, St Louis., MO 63110 (United States); Diamond, Michael S., E-mail: diamond@borcim.wustl.edu [Departments of Medicine, Washington University School of Medicine, St Louis., MO 63110 (United States); Molecular Microbiology, Washington University School of Medicine, St Louis., MO 63110 (United States); Pathology & Immunology, Washington University School of Medicine, St Louis., MO 63110 (United States); The Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, St Louis., MO 63110 (United States)

    2015-05-15

    N-7 and 2′-O methylation of host cell mRNA occurs in the nucleus and results in the generation of cap structures (cap 0, m{sup 7}GpppN; cap 1, m{sup 7}GpppNm) that control gene expression by modulating nuclear export, splicing, turnover, and protein synthesis. Remarkably, RNA cap modification also contributes to mammalian cell host defense as viral RNA lacking 2′-O methylation is sensed and inhibited by IFIT1, an interferon (IFN) stimulated gene (ISG). Accordingly, pathogenic viruses that replicate in the cytoplasm have evolved mechanisms to circumvent IFIT1 restriction and facilitate infection of mammalian cells. These include: (a) generating cap 1 structures on their RNA through cap-snatching or virally-encoded 2′-O methyltransferases, (b) using cap-independent means of translation, or (c) using RNA secondary structural motifs to antagonize IFIT1 binding. This review will discuss new insights as to how specific modifications at the 5′-end of viral RNA modulate host pathogen recognition responses to promote infection and disease.

  18. [Monograph for N-Methyl-pyrrolidone (NMP) and human biomonitoring values for the metabolites 5-Hydroxy-NMP and 2-Hydroxy-N-methylsuccinimide].

    Science.gov (United States)

    2015-10-01

    1-Methyl-pyrrolidone (NMP) is used as a solvent in many technical applications. The general population may be exposed to NMP from the use as ingredient in paint and graffiti remover, indoors also from use in paints and carpeting. Because of developmental toxic effects, the use of NMP in consumer products in the EU is regulated. The developmental effects accompanied by weak maternally toxic effects in animal experiments are considered as the critical effects by the German HBM Commission. Based on these effects, HBM-I values of 10 mg/l urine for children and of 15 mg/l for adults, respectively, were derived for the metabolites 5-Hydroxy-NMP and 2-Hydroxy-N-methylsuccinimide. HBM-II-values were set to 30 mg/l urine for children and 50 mg/l for adults, respectively. Because of similar effects of the structural analogue 1-ethyl-2-pyrrolidone (NEP), the possible mixed exposure to both compounds has to be taken into account when evaluating the total burden.

  19. Synthesis and characterization of a pentadentate Schiff base N3O2 ligand and its neutral technetium(V) complex. X-ray structure of (N,N'-3-azapentane-1,5-diylbis(3-(1-iminoethyl)-6-methyl-2H-pyran-2,4(3H)-dionato)(3-)-O,O',N,N',N double-prime)oxotechnetium(V)

    International Nuclear Information System (INIS)

    Shuang Liu; Rettig, S.J.; Orvig, C.

    1991-01-01

    Preparations of a potentially pentadentate ligand, N,N'-3-azapentane-1,5-diylbis(3-(1-iminoethyl)-6-methyl-2H-pyran-2,4-(3H)-dione) (H 3 apa), and its neutral technetium(V) complex, [TcO(apa)], are described. The 13 C and 1 H NMR, infrared, optical, and mass spectra of the pentadentate ligand and its technetium(V) complex are reported. The X-ray structure of [TcO(apa)] has been determined. Crystals are orthorhombic, space group Pbca, with a = 12.833 (2) angstrom, b = 33.320 (5) angstrom, c = 9.942(4) angstrom, V = 4251 (2) angstrom, and Z = 8. The structure was solved by Patterson and Fourier methods and was refined by full-matrix least-squares procedures to R = 0.028 and R W = 0.032 for 4054 reflections with I ≥ 3σ(I). The technetium(V) complex has a highly distorted octahedral coordination geometry comprising a [TcO] 3+ core and the triply deprotonated pentadentate ligand wrapping around the metal center. One of the two oxygen donor atoms of the pentadentate ligand is located trans to the Tc double-bond O bond while the remaining four donor atoms, N 3 O, occupy the equatorial sites. The distance between the deprotonated N(1) atom to the Tc center is significantly shorter than a normal Tc-N single bond length of 2.10 angstroms, but longer than that for a Tc-N triple bond. 1 H NMR spectral data reveal a rigid solution structure for the complex, which undergoes no conformational and configurational exchange at temperatures up to 50C

  20. Bis(O-n-butyl dithio-carbonato-κS,S')bis-(pyridine-κN)manganese(II).

    Science.gov (United States)

    Alam, Naveed; Ehsan, Muhammad Ali; Zeller, Matthias; Mazhar, Muhammad; Arifin, Zainudin

    2011-08-01

    The structure of the title manganese complex, [Mn(C(5)H(9)OS(2))(2)(C(5)H(5)N)(2)] or [Mn(S(2)CO-n-Bu)(2)(C(5)H(5)N)(2)], consists of discrete monomeric entities with Mn(2+) ions located on centres of inversion. The metal atom is coordinated by a six-coordinate trans-N(2)S(4) donor set with the pyridyl N atoms located in the apical positions. The observed slight deviations from octa-hedral geometry are caused by the bite angle of the bidentate κ(2)-S(2)CO-n-Bu ligands [69.48 (1)°]. The O(CH(2))(3)(CH(3)) chains of the O-n-butyl dithio-carbonate units are disordered over two sets of sites with an occupancy ratio of 0.589 (2):0.411 (2).

  1. Nonparaneoplastic anti-N-methyl-D-aspartate receptor encephalitis: a case series of four children.

    Science.gov (United States)

    Raha, Sarbani; Gadgil, Pradnya; Sankhla, Charulata; Udani, Vrajesh

    2012-04-01

    A rare, severe form of immune-mediated encephalitis recently has been described, associated with antibodies against N-methyl-D-aspartate receptors. It is reported mostly in women with ovarian tumors. Nonparaneoplastic presentations are less common. We describe four children with a neuropsychiatric and extrapyramidal syndrome associated with the presence of anti-N-methyl-D-aspartate receptor antibodies in cerebrospinal fluid and serum, without evidence of neoplasia. Three children recovered completely after immunomodulatory therapy, i.e., intravenous immunoglobulin and/or steroids, methylprednisolone, and/or adrenocorticotrophic hormone. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Binding of indomethacin methyl ester to cyclooxygenase-2. A computational study.

    Science.gov (United States)

    Sárosi, Menyhárt-Botond

    2018-06-05

    Inhibitors selective towards the second isoform of prostaglandin synthase (cyclooxygenase, COX-2) are promising nonsteroidal anti-inflammatory drugs and antitumor medications. Methylation of the carboxylate group in the relatively nonselective COX inhibitor indomethacin confers significant COX-2 selectivity. Several other modifications converting indomethacin into a COX-2 selective inhibitor have been reported. Earlier experimental and computational studies on neutral indomethacin derivatives suggest that the methyl ester derivative likely binds to COX-2 with a similar binding mode as that observed for the parent indomethacin. However, docking studies followed by molecular dynamics simulations revealed two possible binding modes in COX-2 for indomethacin methyl ester, which differs from the experimental binding mode found for indomethacin. Both alternative binding modes might explain the observed COX-2 selectivity of indomethacin methyl ester. Graphical abstract Binding of indomethacin methyl ester to cyclooxygenase-2.

  3. Crystal structures of tetramethylammonium (2,2′-bipyridinetetracyanidoferrate(III trihydrate and poly[[(2,2′-bipyridine-κ2N,N′di-μ2-cyanido-dicyanido(μ-ethylenediamine(ethylenediamine-κ2N,N′cadmium(IIiron(II] monohydrate

    Directory of Open Access Journals (Sweden)

    Songwuit Chanthee

    2016-05-01

    Full Text Available The crystal structures of the building block tetramethylammonium (2,2′-bipyridine-κ2N,N′tetracyanidoferrate(III trihydrate, [N(CH34][Fe(CN4(C10H8N2]·3H2O, (I, and a new two-dimensional cyanide-bridged bimetallic coordination polymer, poly[[(2,2′-bipyridine-κ2N,N′di-μ2-cyanido-dicyanido(μ-ethylenediamine-κ2N:N′(ethylenediamine-κ2N,N′cadmium(IIiron(II] monohydrate], [CdFe(CN4(C10H8N2(C2H8N22]·H2O, (II, are reported. In the crystal of (I, pairs of [Fe(2,2′-bipy(CN4]− units (2,2′-bipy is 2,2′-bipyridine are linked together through π–π stacking between the pyridyl rings of the 2,2′-bipy ligands to form a graphite-like structure parallel to the ab plane. The three independent water molecules are hydrogen-bonded alternately with each other, forming a ladder chain structure with R44(8 and R66(12 graph-set ring motifs, while the disordered [N(CH34]+ cations lie above and below the water chains, and the packing is stabilized by weak C—H...O hydrogen bonds. The water chains are further linked with adjacent sheets into a three-dimensional network via O—H...O hydrogen bonds involving the lattice water molecules and the N atoms of terminal cyanide groups of the [Fe(2,2′-bipy(CN4]− building blocks, forming an R44(12 ring motif. Compound (II features a two-dimensional {[Fe(2,2′-bipy(CN4Cd(en2]}n layer structure (en is ethylenediamine extending parallel to (010 and constructed from {[Fe(2,2′-bipy(CN4Cd(en]}n chains interlinked by bridging en ligands at the Cd atoms. Classical O—H...N and N—H...O hydrogen bonds involving the lattice water molecule and N atoms of terminal cyanide groups and the N—H groups of the en ligands are observed within the layers. The layers are further connected via π–π stacking interactions between adjacent pyridine rings of the 2,2′-bipy ligands, completing a three-dimensional supramolecular structure.

  4. Clinically significant response to zolpidem in disorders of consciousness secondary to anti-N-methyl-D-aspartate receptor encephalitis in a teenager: a case report.

    Science.gov (United States)

    Appu, Merveen; Noetzel, Michael

    2014-03-01

    Anti-N-methyl-d-aspartate receptor encephalitis has been associated with a prolonged neuropsychiatric phase that may last for months to years. We report the case of a 16-year-old girl who was diagnosed with anti-N-methyl-d-aspartate receptor encephalitis resulting from left ovarian mature teratoma 2 weeks after presentation with psychosis. Following tumor removal and immunotherapy, recovery from a minimally conscious state was accelerated significantly by zolpidem that was used for her sleep disturbance. Our patient was discharged home 8 weeks after admission with marked improvement in her neurological function. Zolpidem has been reported to improve arousal in disorders of consciousness but there are no previous reports of its benefit among patients with anti-N-methyl-d-aspartate receptor encephalitis. Zolpidem would be a reasonable consideration as an adjunctive treatment in anti-N-methyl-d-aspartate receptor encephalitis after tumor removal and immunotherapy to accelerate recovery and rehabilitation. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Synthesis and characterization of chromium(III), manganese(II), iron(III), cobalt(II), nickel(II), copper(II), cadmium(II) and dioxouranium(VI) complexes of 4(2-pyridyl)-1-(2,4-dihydroxybenzaldehyde)-3-thiosemicarbazone

    International Nuclear Information System (INIS)

    Abu El-Reash, G.M.; Ibrahim, M.M.; Kenawy; El-Ayaan, Usama; Khattab, M.A.

    1994-01-01

    A few complexes of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and dioxouranium(VI) with 4(2-pyridyl)-1-(2,4-dihydroxybenzaldehyde)-3-thiosemicarbazone have been synthesised and characterized on the basis of elemental analysis, IR, electronic NMR, and magnetic moment data. An octahedral structure is proposed for the Cr(III), Fe(III), Co(II) and Ni(H 3 PBT) 2 Cl 2 .2H 2 O complexes; a tetrahedral structure for the Mn(II) and Ni 2 (PBT)OAc.H 2 0 complexes and a square planar structure for the Cu(II) complexes. The antimicrobial and antifungal activities of H 3 PBT and of its metal(II) complexes are investigated. The results reveal that H 3 PBT exhibits greater antimicrobial activities than its complexes. (author). 34 refs., 4 figs., 2 tabs

  6. Templated synthesis, postsynthetic metal exchange, and properties of a porphyrin-encapsulating metal-organic material

    KAUST Repository

    Zhang, ZhenJie

    2012-01-18

    Reaction of biphenyl-3,4′,5-tricarboxylate (H 3BPT) and CdCl 2 in the presence of meso-tetra(N-methyl-4-pyridyl)porphine tetratosylate (TMPyP) afforded porph@MOM-10, a microporous metal-organic material containing CdTMPyP cations encapsulated in an anionic Cd(II) carboxylate framework, [Cd 6(BPT) 4Cl 4(H 2O) 4]. Porph@MOM-10 is a versatile platform that undergoes exchange to serve as the parent of a series of porph@MOMs that exhibit permanent porosity and heterogeneous catalytic activity. © 2011 American Chemical Society.

  7. Alkylation of deoxyribonucleic acid by carcinogens dimethyl sulphate, ethyl methanesulphonate, N-ethyl-N-nitrosourea and N-methyl-N-nitrosourea

    International Nuclear Information System (INIS)

    Swenson, D.H.; Lawley, P.D.

    1978-01-01

    The ethyl phosphotriester of thymidylyl(3'-5')thymidine, dTp((Et) dT, was identified as a product from the reaction of DNA with N-ethyl-N-nitrosourea. Enzymic degradation to yield alkyl phosphotriesters from DNA alkylated by this carcinogen, and by N-methyl-N-nitrosourea, dimethyl sulphate and ethyl methanesulphonate was studied quantitatively, and the relative yields of the triesters dTp(Alk)dT were determined. The relative reactivity of the phosphodiester group dTpdT to each of the four carcinogens was thus obtained, and compared with that of DNA overall, or with that of the N-7 atom of guanine in DNA. The results are related to steric factors, and the electrophilic character of each carcinogen. (author)

  8. 40 CFR 721.9900 - Urea, condensate with poly[oxy(methyl-1,2-ethanediyl)]-α- (2-aminomethylethyl)-μ-(2-amino...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Urea, condensate with poly[oxy(methyl... Substances § 721.9900 Urea, condensate with poly[oxy(methyl-1,2-ethanediyl)]-α- (2-aminomethylethyl)-μ-(2.... (1) The chemical substance urea, condensate with poly[oxy(methyl-1,2-ethanediyl)]-α-(2...

  9. 2-Amino­benzoic acid–4-[2-(pyridin-4-yl)eth­yl]pyridine (2/1)

    OpenAIRE

    Arman, Hadi D.; Tiekink, Edward R. T.

    2013-01-01

    The asymmetric unit of the title co-crystal, C12H12N2·2C7H7NO2, comprises a centrosymmetric 4-[2-(pyridin-4-yl)ethyl]pyridine molecule and a 2-aminobenzoic acid molecule in a general position. The acid has a small twist between the carboxylic acid residue and the ring [dihedral angle = 7.13 (6)°] despite the presence of an intramolecular N—H...O(carbonyl) hydrogen bond. Three-molecule aggregates are formed via O—H...N(pyridyl) hydrogen bonds, and these are connecte...

  10. Rapid analysis of heterogeneously methylated DNA using digital methylation-sensitive high resolution melting: application to the CDKN2B (p15) gene

    DEFF Research Database (Denmark)

    Candiloro, Ida Lm; Mikeska, Thomas; Hokland, Peter

    2008-01-01

    ABSTRACT: BACKGROUND: Methylation-sensitive high resolution melting (MS-HRM) methodology is able to recognise heterogeneously methylated sequences by their characteristic melting profiles. To further analyse heterogeneously methylated sequences, we adopted a digital approach to MS-HRM (dMS-HRM) t......ABSTRACT: BACKGROUND: Methylation-sensitive high resolution melting (MS-HRM) methodology is able to recognise heterogeneously methylated sequences by their characteristic melting profiles. To further analyse heterogeneously methylated sequences, we adopted a digital approach to MS-HRM (d......MS-HRM) that involves the amplification of single templates after limiting dilution to quantify and to determine the degree of methylation. We used this approach to study methylation of the CDKN2B (p15) cell cycle progression inhibitor gene which is inactivated by DNA methylation in haematological malignancies...... the methylated alleles and assess the degree of methylation. Direct sequencing of selected dMS-HRM products was used to determine the exact DNA methylation pattern and confirmed the degree of methylation estimated by dMS-HRM. CONCLUSION: dMS-HRM is a powerful technique for the analysis of methylation in CDKN2B...

  11. Methylation of deoxycytidine incorporated by excision-repair synthesis of DNA

    International Nuclear Information System (INIS)

    Kastan, M.B.; Gowans, B.J.; Lieberman, M.W.

    1982-01-01

    Methylation of deoxycytidine incorporated by DNA excision-repair was studied in human diploid fibroblasts following damage with ultraviolet radiation, N-methyl-N-nitrosourea, or N-acetoxy-2-acetylaminofluorene. In confluent, nondividing cells, methylation in repair patches induced by all three agents is slow and incomplete. Whereas after DNA replication in logarithmic-phase cultures a steady state level of 3.4% 5-methylcytosine is reached in less than 2 hr after cells are labeled with 6- 3H-deoxycytidine, following ultraviolet-stimulated repair synthesis in confluent cells it takes about 3 days to reach a level of approximately 2.0% 5-methylcytosine in the repair patch. In cells from cultures in logarithmic-phase growth, 5-methylcytosine formation in ultraviolet-induced repair patches occurs faster and to a greater extent, reaching a level of approximately 2.7% in 10-20 hr. Preexisting hypomethylated repair patches in confluent cells are methylated further when the cells are stimulated to divide; however, the repair patch may still not be fully methylated before cell division occurs. Thus DNA damage and repair may lead to heritable loss of methylation at some sites

  12. Rhodosporidium BANNO: Inactivation of yeast phase cells by ultraviolet light and N-methyl-N'-nitro-N-nitrosoguanidine

    International Nuclear Information System (INIS)

    Boettcher, F.; Samsonova, I.A.

    1977-01-01

    The inactivation of stationary phase cells by ultraviolet light (UV) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) was examined in eight wild strains of Rhodotorula, six of which are the sporidial yeast phase of Rhodosporidium, a basidiomycetous fungus. It thas been found that (1) the UV-resistance of Rhodosporidium and Rhodotorula yeasts is higher and the MNNG-resistance lower than the resistance of Candida and Hansenula yeasts, (2) the shape of the survival curves is sigmoid in the case of UV and two-phase exponential in the case of MNNG, (3) the mutagen sensitivities but not the inactivation kinetics of the strains are different, (4) the UV- and MNNG-sensitivities for each of the strains are correlated, (5) the relatively high resistance to UV cannot be due to the carotenoid pigments of the cells, (6) mutations to UV-sensitivity can be induced with a high rate, (7) the sigmoidal character of the UV survival curves were reduced or transformed to an exponential shape by the UVS-mutations. (author)

  13. Photocatalytic degradation of Acephate, Omethoate, and Methyl parathion by Fe_3O_4@SiO_2@mTiO_2 nanomicrospheres

    International Nuclear Information System (INIS)

    Zheng, Lingling; Pi, Fuwei; Wang, Yifan; Xu, Hui; Zhang, Yinzhi; Sun, Xiulan

    2016-01-01

    Highlights: • An efficient photocatalyst Fe_3O_4@SiO_2@mTiO_2 with high magnetic response and large specific surface area was synthesized. • Photocatalytic efficiency of Fe_3O_4@SiO_2@mTiO_2 on Acephate, Omethoate, and Methyl Parathion was higher than TiO_2 P-25. • Possible photocatalytic degradation mechanisms for the Acephate, Omethoate, and Methyl Parathion were proposed. - Abstract: A novel magnetic mesoporous nanomicrospheres Fe_3O_4@SiO_2@mTiO_2 were synthetized and characterized by a series of techniques including FE-TEM, EDS, FE-SEM, PXRD, XPS, BET, TGA as well as VSM, and subsequently tested as a photocatalyst for the degradation of Acephate, Omethoate, and Methyl parathion under UV irradiation. The well-designed nanomicrospheres exhibit a pure and highly crystalline anatase TiO_2 layer, large specific surface area, and high-magnetic-response. Photocatalytic degradation of the three organophosphorus pesticides (OPPs) and the formation intermediates were identified using HPLC, TOC-V_c_p_n, IC, pH meter and GC–MS. Acephate, Omethoate, and Methyl parathion disappeared after 45 min, 45 min, and 80 min UV illumination, respectively. At the end of the treatment, the total organic carbon (TOC) of the OPPs was reduced 80–85%. The main mineralization products were SO_4"2"−, NO_3"− and PO_4"3"− and Omethoate additionally formed NO_2"−. Based on the results, we proposed the photocatalytic degradation pathways for Acephate, Omethoate, and Methyl parathion.

  14. 2-[(4-Bromophenylimino)methyl]-5-pentadecylphenol

    OpenAIRE

    Basavaraj Padmashali; Patchanita Thamyongkit; Amorn Petsom; Gadada Naganagowda

    2012-01-01

    2-[(4-Bromophenylimino)methyl]-5-pentadecylphenol has been synthesized by reaction of 2-hydroxy-4-pentadecylbenzaldehyde with 4-bromoaniline in 1,4-dioxane and its IR, 1H-NMR, 13C-NMR and MS spectroscopic data are presented.

  15. Radiosynthesis of N-¹¹C-Methyl-Taurine-Conjugated Bile Acids and Biodistribution Studies in Pigs by PET/CT.

    Science.gov (United States)

    Schacht, Anna Christina; Sørensen, Michael; Munk, Ole Lajord; Frisch, Kim

    2016-04-01

    During cholestasis, accumulation of conjugated bile acids may occur in the liver and lead to hepatocellular damage. Inspired by our recent development of N-(11)C-methyl-glycocholic acid-that is, (11)C-cholylsarcosine-a tracer for PET of the endogenous glycine conjugate of cholic acid, we report here a radiosynthesis of N-(11)C-methyl-taurine-conjugated bile acids and biodistribution studies in pigs by PET/CT. A radiosynthesis of N-(11)C-methyl-taurine-conjugated bile acids was developed and used to prepare N-(11)C-methyl-taurine conjugates derived from cholic, chenodeoxycholic, deoxycholic, ursodeoxycholic, and lithocholic acid. The lipophilicity of these new tracers was determined by reversed-phase thin-layer chromatography. The effect of lipophilicity and structure on the biodistribution was investigated in pigs by PET/CT using the tracers derived from cholic acid (3α-OH, 7α-OH, 12α-OH), ursodeoxycholic acid (3α-OH, 7β-OH), and lithocholic acid (3α-OH). The radiosyntheses of the N-(11)C-methyl-taurine-conjugated bile acids proceeded with radiochemical yields of 61% (decay-corrected) or greater and radiochemical purities greater than 99%. PET/CT in pigs revealed that the tracers were rapidly taken up by the liver and secreted into bile. There was no detectable radioactivity in urine. Significant reflux of N-(11)C-methyl-taurolithocholic acid into the stomach was observed. We have successfully developed a radiosynthesis of N-(11)C-methyl-taurine-conjugated bile acids. These tracers behave in a manner similar to endogenous taurine-conjugated bile acids in vivo and are thus promising for functional PET of patients with cholestatic diseases. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  16. Effects of pilocarpine and kainate-induced seizures on N-methyl-d-aspartate receptor gene expression in the rat hippocampus

    Energy Technology Data Exchange (ETDEWEB)

    Przewlocka, B.; Labuz, D.; Machelska, H.; Przewlocki, R.; Turchan, J.; Lason, W. [Department of Molecular Neuropharmacology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smetna Street, 31-343 Krakow (Poland)

    1997-04-14

    The effects of pilocarpine- and kainate-induced seizures on N-methyl-d-aspartate receptor subunit-1 messenger RNA and [{sup 3}H]dizocilpine maleate binding were studied in the rat hippocampal formation. Pilocarpine- but not kainate-induced seizures decreased N-methyl-d-aspartate receptor subunit-1 messenger RNA level in dentate gyrus at 24 and 72 h after drug injection. Both convulsants decreased the messenger RNA level in CA1 pyramidal cells at 24 and 72 h, the effects of kainate being more profound. Kainate also decreased the N-methyl-d-aspartate receptor subunit-1 messenger RNA level in CA3 region after 24 and 72 h, whereas pilocarpine decreased the messenger RNA level at 72 h only. At 3 h after kainate, but not pilocarpine, an increased binding of [{sup 3}H]dizocilpine maleate in several apical dendritic fields of pyramidal cells was found. Pilocarpine reduced the [{sup 3}H]dizocilpine maleate binding in stratum lucidum only at 3 and 24 h after the drug injection. Pilocarpine but not kainate induced prolonged decrease in N-methyl-d-aspartate receptor subunit-1 gene expression in dentate gyrus. However, at the latest time measured, kainate had the stronger effect in decreasing both messenger RNA N-methyl-d-aspartate receptor subunit-1 and [{sup 3}H]dizocilpine maleate binding in CA1 and CA3 hippocampal pyramidal cells. The latter changes corresponded, however, to neuronal loss and may reflect higher neurotoxic potency of kainate.These data point to some differences in hippocampal N-methyl-d-aspartate receptor regulation in pilocarpine and kainate models of limbic seizures. Moreover, our results suggest that the N-methyl-d-aspartate receptor subunit-1 messenger RNA level is more susceptible to limbic seizures than is [{sup 3}H]dizocilpine maleate binding in the rat hippocampal formation. (Copyright (c) 1997 Elsevier Science B.V., Amsterdam. All rights reserved.)

  17. Effects of pilocarpine and kainate-induced seizures on N-methyl-d-aspartate receptor gene expression in the rat hippocampus

    International Nuclear Information System (INIS)

    Przewlocka, B.; Labuz, D.; Machelska, H.; Przewlocki, R.; Turchan, J.; Lason, W.

    1997-01-01

    The effects of pilocarpine- and kainate-induced seizures on N-methyl-d-aspartate receptor subunit-1 messenger RNA and [ 3 H]dizocilpine maleate binding were studied in the rat hippocampal formation. Pilocarpine- but not kainate-induced seizures decreased N-methyl-d-aspartate receptor subunit-1 messenger RNA level in dentate gyrus at 24 and 72 h after drug injection. Both convulsants decreased the messenger RNA level in CA1 pyramidal cells at 24 and 72 h, the effects of kainate being more profound. Kainate also decreased the N-methyl-d-aspartate receptor subunit-1 messenger RNA level in CA3 region after 24 and 72 h, whereas pilocarpine decreased the messenger RNA level at 72 h only. At 3 h after kainate, but not pilocarpine, an increased binding of [ 3 H]dizocilpine maleate in several apical dendritic fields of pyramidal cells was found. Pilocarpine reduced the [ 3 H]dizocilpine maleate binding in stratum lucidum only at 3 and 24 h after the drug injection. Pilocarpine but not kainate induced prolonged decrease in N-methyl-d-aspartate receptor subunit-1 gene expression in dentate gyrus. However, at the latest time measured, kainate had the stronger effect in decreasing both messenger RNA N-methyl-d-aspartate receptor subunit-1 and [ 3 H]dizocilpine maleate binding in CA1 and CA3 hippocampal pyramidal cells. The latter changes corresponded, however, to neuronal loss and may reflect higher neurotoxic potency of kainate.These data point to some differences in hippocampal N-methyl-d-aspartate receptor regulation in pilocarpine and kainate models of limbic seizures. Moreover, our results suggest that the N-methyl-d-aspartate receptor subunit-1 messenger RNA level is more susceptible to limbic seizures than is [ 3 H]dizocilpine maleate binding in the rat hippocampal formation. (Copyright (c) 1997 Elsevier Science B.V., Amsterdam. All rights reserved.)

  18. Palladium(II) complexes with R(2)edda derived ligands. Part IV. O,O'-dialkyl esters of (S,S)-ethylenediamine-N,N'-di-2-(4-methyl)-pentanoic acid dihydrochloride and their palladium(II) complexes: synthesis, characterization and in vitro antitumoral activity against chronic lymphocytic leukemia (CLL) cells.

    Science.gov (United States)

    Vujić, Jelena M; Cvijović, Milica; Kaluderović, Goran N; Milovanović, Marija; Zmejkovski, Bojana B; Volarević, Vladislav; Arsenijević, Nebojsa; Sabo, Tibor J; Trifunović, Srećko R

    2010-09-01

    Four novel bidentate N,N'-ligand precursors, including O,O'-dialkyl esters (alkyl = ethyl, n-propyl, n-butyl and n-pentyl), L1 x 2 HCl-L4 x 2 HCl, of (S,S)-ethylenediamine-N,N'-di-2-(4-methyl)-pentanoic acid dihydrochloride [(S,S)-H(4)eddl]Cl(2) and the corresponding palladium(II) complexes 1-4, were prepared and characterized by IR, (1)H NMR and (13)C NMR spectroscopy and elemental analysis. In vitro cytotoxicity of all compounds was determined against chronic lymphocytic leukemia cells (CLL). The compounds were found to exhibit higher antitumoral activity than cisplatin. The most active compound 2, [PdCl(2){(S,S)-nPr(2)eddl}], was found to be 13.6 times more active than cisplatin on CLL cells. 2010 Elsevier Masson SAS. All rights reserved.

  19. Oxidation of 2-methyl-1-naphthol to 2-methyl-1,4-naphthoquinone using interphase catalysis in the presence of vanadomolybdophosphoric heteropolyacids

    International Nuclear Information System (INIS)

    Matveev, K.I.; Zhizhina, E.G.; Odyakov, V.F.; Parmon, V.N.

    1994-01-01

    2-Methyl-1-naphthol is oxidized by air to 2-methyl-1,4-naphthoquinone (menadione) in the presence of vanadomolybdophosphoric heteropolyacids or their acid salts. This reaction proceeds in a two-phase system with the yield of up to 85 %. The influence of heteropolyacid composition on the reaction rate and its selectivity has been studied and the reaction mechanism has been proposed. 7 refs.; 1 fig.; 1 tab

  20. MicroRNA-219-2-3p functions as a tumor suppressor in gastric cancer and is regulated by DNA methylation.

    Directory of Open Access Journals (Sweden)

    Huizi Lei

    Full Text Available BACKGROUND AIMS: Gastric cancer is the most frequent gastrointestinal tumor in adults and is the most lethal form of human cancer. Despite of the improvements in treatments, the underlying mechanism of gastric carcinogenesis is not well known. To define novel modulators that regulate susceptibility to tumorgenesis, we focused on miR-219-2-3p. METHODS: Quantitative RT-PCR was employed to investigate the level of miR-219-2-3p in gastric cancer (GC tissues (n = 113 and their matched adjacent normal tissues (n = 113. In vitro cell proliferation, apoptosis assays, cell migration, and invasion assays were performed to elucidate biological effects of miR-219-2-3p. Since silencing of miRNA by promoter CpG island methylation may be an important mechanism in tumorgenesis, GC cells were treated with 5-aza-2'-deoxycytidine and trichostatin A, and expression changes of miR-219-2-3p were subsequently examined by quantitative RT-PCR. Finally, the methylation status of CpG island upstream of miR-219-2-3p was analyzed by methylation-specific PCR in GC tissues (n = 22. RESULTS: miR-219-2-3p was down-regulated in GC and cell lines. In addition, the experiments documented the lower expression of miR-219-2-3p in GC specimens with higher grade and later stage tumors. Meanwhile, miR-219-2-3p exerted antiproliferative, proapoptotic, and antimetastatic roles and reduced levels of p-ERK1/2 in GC cells. Furthermore, 5-aza-2'-deoxycytidine and trichostatin A increased the expression (~2 fold of miR-219-2-3p in GC cells. By methylation-specific PCR, DNA methylation in the upstream region of miR-219-2-3p was detected in both adjacent normal tissues and cancer tissues. As expected, the methylation level was considerably higher in the miR-219-2-3p down-regulated group than up-regulated group. CONCLUSIONS: miR-219-2-3p is potentially involved in gastric cancer progression and metastasis by regulating ERK1/2-related signal pathways, which may provide a novel therapeutic strategy

  1. Ferrocene Compounds. XXVI. C- and O-Ferrocenylalkylation of Methyl Salicylate

    OpenAIRE

    Kovač, Veronika; Rapić, Vladimir; Alagić, Jasmina; Barišić, Lidija

    1999-01-01

    Reaction of equimolar amounts of methyl salicylate, sodium and N,N,N-trimethylferrocylammonium iodide (1a) in ethanol gave 55% of ethyl 1-ferrocenylethyl ether (4). By refluxing a solution of 9 mmol sodium and 3 mmol of FcCHRNMe3I (1a, R = H; 1b, R = Me; 1c, R = Ph) in a large excess of methyl salicylate for 2-3 hours, the corresponding methyl 5-ferrocylsalicylates (5) (10-23%) and methyl-3-ferrocylsalicylates (6) (12-20%) were obtained. During conversion of salt 1b, besides of 5b and 6b, 20%...

  2. Insights into the coal extractive solvent N-methyl-2-pyrrolidone + carbon disulfide

    Energy Technology Data Exchange (ETDEWEB)

    Santiago Aparicio; Mara J. Davila; Rafael Alcalde [University of Burgos, Burgos (Spain). Department of Chemistry

    2009-03-15

    A wide set of experimental and computational tools were used to characterize the N-methyl-2-pyrrolidone (NMP) + carbon disulfide mixed solvent in the full composition range. The interest in this solvent rose from its very efficient use for coal extraction through a mechanism still not fully understood. Thermophysical properties at ambient pressure together with pressure-volume-temperature (PVT) behavior were measured with the objective of providing the required data for the industrial use of the mixed fluid and to get insight into the fluid structure at the molecular level. NMR, FTIR, and solvatochromic studies were performed together with microwave dielectric relaxation spectroscopy (DRS) measurements, thus providing more information on the fluid's structure and allowing one to relate the molecular level behavior with the measured macroscopic properties. Moreover, density functional theory (DFT) and classical molecular dynamics simulations (MD) were used to obtain a detailed picture of the intermolecular interactions within the fluid, at short and long ranges, and of other relevant features leading to the structure of the studied system. The whole study leads to a fluid's picture in which carbon disulfide hinders the development of NMP/NMP intermolecular dipolar interactions, thus increasing the monomer population. We should remark that some properties reported in this work are in remarkable disagreement with previously reported studies, the most important one being the positive excess molar volume in the whole pressure-temperature range studied, which contrasts with the negative values reported in the literature. Previously reported properties are hardly justified with a coherent molecular level picture, whereas the whole collection of properties reported in this work leads to a more reasonable fluid's structure. 56 refs., 17 figs., 2 tabs.

  3. 5-Chloro-2-(2'-((dimethylamino)methyl)-4'-iodophenylthio)benzenamine: a new serotonin transporter ligand

    International Nuclear Information System (INIS)

    Oya, Shunichi; Choi, Seok-Rye; Kung, Mei-Ping; Kung, Hank F.

    2007-01-01

    Two novel ligands with 4' substitution on the Phenyl Ring B of biphenylthiol, 5-chloro-2-(2'-((dimethylamino)methyl)-4'-iodophenylthio)benzenamine (7) and 2-(2'-((dimethylamino)methyl)-4'-methoxyphenylthio)-5-iodobenzenamine (8), were prepared and tested as potential serotonin transporter (SERT) imaging agents. The new ligands displayed extremely high binding affinities to SERT (K i =0.22±0.09 and 0.11±0.04 nM, respectively), with very low binding affinities to dopamine and norepinephrine transporters (K i >1000 nM). The corresponding [ 125 I]7 and [ 125 I]8 were successfully prepared from tri-n-butyltin derivatives. They showed good brain uptakes and prolonged retention after intravenous injection in rats (brain uptake was 1.77% and 0.98% dose/g for [ 125 I]7, and 0.92% and 0.29% dose/g for [ 125 I]8, at 2 and 120 min, respectively). Significantly, [ 125 I]7 showed excellent uptake and prolonged retention in the hypothalamus, where SERT concentration was highest. The hypothalamus/cerebellum (HY/CB) ratios (target/background ratios) were 4.24, 7.10, 8.24 and 12.6 at 2, 4, 6 and 12 h, respectively. The HY/CB ratios for [ 125 I]8 were 3.97, 5.57 and 5.06 at 1, 2 and 4 h, respectively. Adding the 4'-iodo group to the Phenyl Ring B of Compound (7) appeared to reduce the rate of clearance from the brain, and kinetics favored uptake and retention in the hypothalamus. The localization of [ 125 I]7 in the hypothalamus region in the rat brain could be blocked by pretreatment with (+)McN5652, escitalopram and ADAM (2), which are all selective SERT ligands (at 2 mg/kg iv, 5 min pretreatment). Ex vivo autoradiograms of rat brain sections (at 4 h after intravenous injection of [ 125 I]7) showed intense labeling in regions of the brain known to have high SERT density. The excellent selective uptake and retention in the hypothalamus region suggest that [ 123 I]7 is a potential lead compound for developing new imaging agents targeting SERT-binding sites with single

  4. Synthesis of N-oleyl O-sulfate chitosan from methyl oleate with O-sulfate chitosan as edible film material

    Science.gov (United States)

    Daniel; Sihaloho, O.; Saleh, C.; Magdaleni, A. R.

    2018-04-01

    The research on the synthesis of N-oleyl O-sulfate chitosan through sulfonation reaction on chitosan with ammonium sulfate and followed by amidation reaction using methyl oleate has been done. In this study, chitosan was chemically modified into N-oleyl O-sulfatechitosan as an edible film making material. N-oleyl O-sulfate chitosan was synthesized by reaction between methyl oleate and O-sulfate chitosan. Wherein the depleted chitosan of O-sulfate chitosan into O-sulfate chitosan was obtained by reaction of sulfonation between ammonium sulfate and chitosan aldimine. While chitosan aldimine was obtained through reaction between chitosan with acetaldehyde. The structure of N-oleyl O-sulfate chitosan was characterized by FT-IR analysis which showed vibration uptake of C-H sp3 group, S=O group, and carbonyl group C=O of the ester. The resulting of N-oleyl O-sulfate chitosan yielded a percentage of 93.52%. Hydrophilic-Lipophilic Balance (HLB) test results gave a value of 6.68. In the toxicity test results of N-oleyl O-sulfate chitosan obtained LC50 value of 3738.4732 ppm. In WVTR (Water Vapor Transmission Rate) test results for chitosan film was 407.625 gram/m2/24 hours and N-oleylO-sulfate chitosan film was 201.125 gram/m2/24 hours.

  5. Synthesis, Spatial Structure and Analgesic Activity of Sodium 3-Benzylaminocarbonyl-1-methyl-2,2-dioxo-1H-2λ6,1-benzothiazin-4-olate Solvates

    Directory of Open Access Journals (Sweden)

    Igor V. Ukrainets

    2016-10-01

    Full Text Available In order to obtain and then test pharmocologically any possible conformers of the new feasible analgesic N-benzyl-4-hydroxy-1-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxamide, its 4-O-sodium salt was synthesized using two methods. X-ray diffraction study made possible to determine that, depending on the chosen synthesis conditions, the above-mentioned compound forms either monosolvate with methanol or monohydrate, where organic anion exists in the form of three different conformers. Pharmacological testing of the two known pseudo-enantiomeric forms of the original N-benzylamide and of the two solvates of its sodium salt was performed simultaneously under the same conditions and in equimolar doses. Comparison of the results obtained while studying the peculiarities of the synthesized compounds spatial structure and biological properties revealed an important structure-action relationship. In particular, it was shown that the intensity of analgesic effect of different conformational isomers of N-benzyl-4-hydroxy-1-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxamide may change considerably: while low active conformers are comparable with piroxicam, highly active conformers are more than twice as effective as meloxicam.

  6. Removal of methyl violet dye by adsorption onto N-benzyltriazole derivatized dextran

    DEFF Research Database (Denmark)

    Cho, Eunae; Tahir, Muhammad Nazir; Kim, Hwanhee

    2015-01-01

    In this work, N-benzyltriazole derivatized dextran was evaluated for its potential as a novel carbohydrate-based adsorbent for the removal of methyl violet dye from water. The modified dextran was synthesized by a click reaction of pentynyl dextran and benzyl azide, and the structure...... was characterized by nuclear magnetic resonance spectroscopy, elemental analysis, and scanning electron microscopy. Dextran was substituted with a triazole-linked benzyl group. For decolorization of the dye effluent, adsorption is a very effective treatment; here, the driving force is based on hydrogen bonding, pi...... stacking, and electrostatic interaction between the methyl violet dye and the N-benzyltriazole derivatized dextran. Batch experiments were carried out to investigate the required contact time and the effects of pH, initial dye concentrations, and temperature. The experimental data were analyzed...

  7. 2-Amino­benzoic acid–4,4′-bi­pyridine (2/1)

    OpenAIRE

    Arman, Hadi D.; Tiekink, Edward R. T.

    2013-01-01

    The asymmetric unit of title co-crystal, C10H8N2·2C7H7NO2, comprises a centrosymmetric 4,4′-bipyridine molecule, and a 2-aminobenzoic acid molecule in a general position. The latter is effectively planar [C—C—C—O torsion angle = 5.0 (3)°] owing to an intramolecular N—H...O(carbonyl) hydrogen bond. Three-molecule aggregates are formed via O—H...N(pyridyl) hydrogen bonds and these are connected into supramolecular layers in the bc plane by N&#...

  8. Titanium (III) cation selective electrode based on synthesized tris(2pyridyl) methylamine ionophore and its application in water samples

    Science.gov (United States)

    Rezayi, Majid; Karazhian, Reza; Abdollahi, Yadollah; Narimani, Leila; Sany, Seyedeh Belin Tavakoly; Ahmadzadeh, Saeid; Alias, Yatimah

    2014-04-01

    The introduction of low detection limit ion selective electrodes (ISEs) may well pave the way for the determination of trace targets of cationic compounds. This research focuses on the detection of titanium (III) cation using a new PVC-membrane sensor based on synthesized tris(2pyridyl) methylamine (tpm) ionophore. The application and validation of the proposed sensor was done using potentiometric titration, inductively coupled plasma atomic emission spectrometry (ICP-AES), and atomic absorption spectrometry (AAS). The membrane sensor exhibited a Nernstian response to the titanium (III) cation over a concentration range of 1.0 × 10-6-1.0 × 10-2 M and pH range from 1-2.5. The Nernstian slope, the lower of detection (LOD), and the response time (t95%) of the proposed sensor were 29.17 +/- 0.24 mV/dec, 7.9 × 10-7 M, and 20 s, respectively. The direct determination of 4-39 μg/ml of titanium (III) standard solution showed an average recovery of 94.60 and a mean relative standard deviation of 1.8 at 100.0 μg/ml. Finally, the utilization of the electrodes as end-point indicators for potentiometric titration with EDTA solutions for titanium (III) sensor was successfully carried out.

  9. Analysis of variations in the glutamate receptor, N-methyl D-aspartate 2A (GRIN2A gene reveals their relative importance as genetic susceptibility factors for heroin addiction.

    Directory of Open Access Journals (Sweden)

    Bin Zhao

    Full Text Available The glutamate receptor, N-methyl D-aspartate 2A (GRIN2A gene that encodes the 2A subunit of the N-methyl D-aspartate (NMDA receptor was recently shown to be involved in the development of opiate addiction. Genetic polymorphisms in GRIN2A have a plausible role in modulating the risk of heroin addiction. An association of GRIN2A single-nucleotide polymorphisms (SNPs with heroin addiction was found earlier in African Americans. To identify markers that contribute to the genetic susceptibility to heroin addiction, we examined the potential association between heroin addiction and forty polymorphisms of the GRIN2A gene using the MassARRAY system and GeneScan in this study. The frequency of the (GT26 repeats (rs3219790 in the heroin addiction group was significantly higher than that in the control group (χ(2 = 5.360, P = 0.021. The allele frequencies of three polymorphisms (rs1102972, rs1650420, and rs3104703 in intron 3 were strongly associated with heroin addiction (P<0.001, 0.0002, and <0.001, after Bonferroni correction. Three additional SNPs from the same intron (rs1071502, rs6497730, and rs1070487 had nominally significant P values for association (P<0.05, but did not pass the threshold value. Haplotype analysis revealed that the G-C-T-C-C-T-A (block 6 and T-T (block 10 haplotypes of the GRIN2A gene displayed a protective effect (P = <0.001 and 0.003. These findings point to a role for GRIN2A polymorphisms in heroin addiction among the Han Chinese from Shaanxi province, and may be informative for future genetic or neurobiological studies on heroin addiction.

  10. [Inactivation of PMS2 gene by promoter methylation in nasopharyngeal carcinoma].

    Science.gov (United States)

    Ni, H F; Jiang, B; Zhou, Z; Li, Y; Yuan, X Y; Cao, X L; Huang, G W

    2016-11-23

    Objective: To investigate the inactivation of PMS2 gene mediated by promoter methylation and its regulatory mechanism in nasopharyngeal carcinoma (NPC). Methods: Fifty-four NPC tissues, 16 normal nasopharyngeal epithelia (NNE), 5 NPC cell lines (CNE1, CNE2, TWO3, HNE1 and HONE1) and 1 normal nasopharyngeal epithelial cell line (NP69) were collected.Methylation-specific PCR (MSP) was used to detect the PMS2 promoter methylation, semi-quantitative reverse transcription PCR (qRT-PCR) was applied to determine its mRNA expression, and immunohistochemistry (IHC) was used to detect the protein expression of PMS2. The expressions of PMS2 mRNA in CNE1 and CNE2 cells before and after treated with methyltransferase inhibitor 5-aza-2-deoxycytidine were analyzed by qRT-PCR. The impact of methylation and demethylation on the mRNA expression of PMS2, and the association of mRNA and protein expression of PMS2 with clinicopathological features of nasopharyngeal cancer were analyzed. Results: Methylation of PMS2 gene was detected in all of the five NPC cell lines, but not in normal nasopharyngeal epithelial NP69 cells. The methylation rate of PMS2 gene in NPC tissues was 63% (34/54), significantly higher than that of the normal nasopharyngeal epithelia (0/16, P PMS2 mRNA and protein were significantly down-regulated in the 54 NPC tissues when compared with those in the 16 NNE tissues ( P PMS2 mRNA was restored in the CNE1 and CNE2 cells.However, the expressions of PMS2 mRNA and protein were not significantly correlated with patients' age, gender, TNM stage, histopathologic type or lymph node metastasis ( P >0.05 for all). Conclusions: Promoter methylation-mediated inactivation of PMS2 gene participates in carcinogenesis and development of NPC. PMS2 may be a candidate tumor suppressor in the treatment for patients with inactivation of PMS2 promoter methylation.

  11. Iodine-123 N-methyl-4-iododexetimide: a new radioligand for single-photon emission tomographic imaging of myocardial muscarinic receptors

    International Nuclear Information System (INIS)

    Hicks, R.J.; Kassiou, M.; Eu, P.; Katsifis, A.G.; Garra, M.; Power, J.; Najdovski, L.; Lambrecht, R.M.

    1995-01-01

    Cardiac muscarinic receptor ligands suitable for positron emission tomography have previously been characterised. Attempts to develop radioligands of these receptors suitable for single-photon emission tomographic (SPET) imaging have not been successful due to high lung retention and high non-specific binding of previously investigated potential tracers. The purpose of this study was to evaluate the biodistribution and in vivo imaging characteristics of a new radiopharmaceutical, [ 123 I]N-methyl-4-iododexetimide. Biodistribution studies performed in rats showed high cardiac uptake (2.4% ID/g) 10 min after injection with a heart to lung activity ratio of 5:1. Specificity and stereoselectivity of cardiac binding were demonstrated using blocking experiments in rats. Dynamic imaging studies in anaesthetised greyhounds demonstrated rapid and high myocardial uptake and low lung binding with stable heart to lung activity ratios of >2.5:1 between 10 and 30 min, making SPET imaging feasible. Administration of an excess of an unlabelled muscarinic antagonist, methyl-quinuclidinyl benzylate rapidly displaced myocardial activity to background levels and the pharmacologically inactive enantiomer, [ 123 I]N-methyl-4-iodolevetimide, had no detectable cardiac uptake, indicating specific and stereoselective muscarinic receptor binding. SPET revealed higher activity in the inferior than in the anterior wall, this being consistent with previously described regional variation of cardiac parasympathetic innervation. [ 123 I]N-methyl-4-iododexetimide shows promise as an imaging agent for muscarinic receptor distribution in the heart and may be helpful in evaluating diverse cardiac diseases associated with altered muscarinic receptor function, including heart failure and diabetic heart disease. (orig.)

  12. Computational Study of Environmental Effects on Torsional Free Energy Surface of N-Acetyl-N'-methyl-L-alanylamide Dipeptide

    Science.gov (United States)

    Carlotto, Silvia; Zerbetto, Mirco

    2014-01-01

    We propose an articulated computational experiment in which both quantum mechanics (QM) and molecular mechanics (MM) methods are employed to investigate environment effects on the free energy surface for the backbone dihedral angles rotation of the small dipeptide N-Acetyl-N'-methyl-L-alanylamide. This computation exercise is appropriate for an…

  13. 21 CFR 172.872 - Methyl ethyl cellulose.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Methyl ethyl cellulose. 172.872 Section 172.872... CONSUMPTION Multipurpose Additives § 172.872 Methyl ethyl cellulose. The food additive methyl ethyl cellulose... a cellulose ether having the general formula [C6H(10 -x-y)O5(CH3)x(C2H5)y]n, where x is the number...

  14. U.v.-induced and N-methyl-N'-nitrosoguanidine-induced mutagenesis in Bacillus thuringiensis

    International Nuclear Information System (INIS)

    Auffray, Y.; Boutibonnes, P.

    1987-01-01

    The lethal and mutagenic effects of u.v. light and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) on Bacillus thuringiensis were investigated. Lethality studies demonstrated that B. thuringiensis was relatively sensitive to these agents. This bacterium was mutated at the rifampicin resistance marker by u.v. light and to a lesser extent by the direct acting alkylating agent MNNG. One mutant selected for its greater sensitivity to u.v. light expressed a higher frequency of mutagenesis after u.v. light treatment and appeared to be defective in an excision repair pathway. However, this mutant was only slightly mutable by MNNG in comparison with the wild-type strain. This unusual phenotype does not yet have a parallel among the radiation sensitive mutants described in other bacterial species. (author)

  15. Geissoschizine methyl ether N-oxide, a new alkaloid with antiacetylcholinesterase activity from Uncaria rhynchophylla.

    Science.gov (United States)

    Jiang, Wei-Wei; Su, Jia; Wu, Xing-De; He, Juan; Peng, Li-Yan; Cheng, Xiao; Zhao, Qin-Shi

    2015-01-01

    Geissoschizine methyl ether N-oxide, a new oxindole alkaloid, along with 14 known alkaloids, was isolated from the aerial part of Uncaria rhynchophylla. Their structures were identified by comprehensive spectral methods, including 2D NMR experiments, and confirmed by comparing with the literature data. In vitro acetylcholinesterase (AChE) inhibitory activity assay showed that the new compound exhibited anti-AChE activity with IC₅₀ value of 23.4 μM.

  16. Metabolic solutions to the biosynthesis of some diaminomonocarboxylic acids in nature: Formation in cyanobacteria of the neurotoxins 3-N-methyl-2,3-diaminopropanoic acid (BMAA) and 2,4-diaminobutanoic acid (2,4-DAB).

    Science.gov (United States)

    Nunn, Peter B; Codd, Geoffrey A

    2017-12-01

    The non-encoded diaminomonocarboxylic acids, 3-N-methyl-2,3-diaminopropanoic acid (syn: α-amino-β-methylaminopropionic acid, MeDAP; β-N-methylaminoalanine, BMAA) and 2,4-diaminobutanoic acid (2,4-DAB), are distributed widely in cyanobacterial species in free and bound forms. Both amino acids are neurotoxic in whole animal and cell-based bioassays. The biosynthetic pathway to 2,4-DAB is well documented in bacteria and in one higher plant species, but has not been confirmed in cyanobacteria. The biosynthetic pathway to BMAA is unknown. This review considers possible metabolic routes, by analogy with reactions used in other species, by which these amino acids might be biosynthesised by cyanobacteria, which are a widespread potential environmental source of these neurotoxins. Where possible, the gene expression that might be implicated in these biosyntheses is discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Synthesis of R-(+)- and S-(-)-8-hydroxy-2-(N,N-dipropylamino)-2[2-3H]tetralin. HCl (8-OH-DPAT) a 5HT1A receptor agonist

    International Nuclear Information System (INIS)

    Ackland, M.J.; Dring, L.G.; Jones, J.R.

    1991-01-01

    The title compounds were synthesised in 7 steps from 1,7-dihydroxynaphthalene as follows: 1,7-dihydroxynaphthalene was methylated and subjected to a Birch reduction to yield 8-methoxy-2-tetralone. Reductive amination with sodium cyanoboro[ 3 H]hydride and n-propylamine gave 8-methoxy-2-(n-propylamino)-[2- 3 H]tetralin which was acylated and reduced to give (±)8-methoxy-2-(N,N-dipropylamino)-[2 3 H]tetralin. Treatment with conc.HC1 gave (±)-8-hydroxy-2-(N,N-dipropylamino)-[2- 3 H]tetralin. The racemate was then resolved by chiral mobile phase chromatography. (author)

  18. Synthesis, growth and characterization of organic nonlinear optical material: N-benzyl-2-methyl-4-nitroaniline (BNA)

    Science.gov (United States)

    Kalaivanan, R.; Srinivasan, K.

    2017-05-01

    Synthesis of the organic nonlinear optical compound N-benzyl-2-methyl-4-nitroaniline (BNA) was carried out in a newer chemical environment using the mixture of benzyl chloride and 2-methl-4-nitroaniline by a preferred laboratory synthesis process. The synthesized BNA compound was separated by column chromatography (CC) with low pressure silica gell using petrollium benzine and purity of the separated resultant product was confirmed by thin layer chromatography (TLC). Further, the material was recrystallized atleast four times in methanol and the highly purified BNA was used for the growth of single crystals from solutions with selected solvents by slow evaporation method at room temperature. Single crystals having natural growth morphology were harvested and their different growth faces were identified by optical goniometry. The grown crystals were subjected to different characterization techniques such as powder x-ray diffraction (PXRD), fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and UV-vis-Near IR spectroscopy. Further, the second harmonic generation (SHG) efficiency of the grown BNA crystal was studied by Kurtz and Perry powder technique using Nd:YAG laser as fundamental source and found to be twice that of inorganic standard KDP.

  19. Cholinergic cells in the nucleus basalis of mice express the N-methyl-D-aspartate-receptor subunit NR2C and its replacement by the NR2B subunit enhances frontal and amygdaloid acetylcholine levels

    NARCIS (Netherlands)

    De Souza Silva, M. A.; Dolga, Amalia; Pieri, I.; Marchetti, L.; Eisel, U. L. M.; Huston, J. P.; Dere, E.

    2006-01-01

    It is known that glutamatergic and cholinergic systems interact functionally at the level of the cholinergic basal forebrain. The N-methyl-D-aspartate receptor (NMDA-R) is a multiprotein complex composed of NR1, NR2 and/or NR3 subunits. The subunit composition of NMDA-R of cholinergic cells in the

  20. Visible-light-induced, Ir-catalyzed reactions of N-methyl-N-((trimethylsilylmethylaniline with cyclic α,β-unsaturated carbonyl compounds

    Directory of Open Access Journals (Sweden)

    Dominik Lenhart

    2014-04-01

    Full Text Available N-Methyl-N-((trimethylsilylmethylaniline was employed as reagent in visible-light-induced, iridium-catalyzed addition reactions to cyclic α,β-unsaturated carbonyl compounds. Typical reaction conditions included the use of one equivalent of the reaction substrate, 1.5 equivalents of the aniline and 2.5 mol % (in MeOH or 1.0 mol % (in CH2Cl2 [Ir(ppy2(dtbbpy]BF4 as the catalyst. Two major reaction products were obtained in combined yields of 30–67%. One product resulted from aminomethyl radical addition, the other product was a tricyclic compound, which is likely formed by attack of the intermediately formed α-carbonyl radical at the phenyl ring. For five-membered α,β-unsaturated lactone and lactam substrates, the latter products were the only products isolated. For the six-membered lactones and lactams and for cyclopentenone the simple addition products prevailed.

  1. Deconjugation of N-glucuronide conjugated metabolites with hydrazine hydrate - Biomarkers for exposure to the food-borne carcinogen 2-amino-l-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)

    DEFF Research Database (Denmark)

    Frandsen, Henrik Lauritz

    2007-01-01

    The metabolism of the carcinogen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) has been investigated in rabbit liver S9. Two phase I metabolites, N-2-OH-PhIP and 4'-OH-PhIP were identified based on UV and mass spectra and co-elution with reference standards. Fortification of the incubation...

  2. Spin state of mixed crystals of iron with zinc or cobalt for the assembled complexes bridged by 1,3-bis(4-pyridyl)propanes

    International Nuclear Information System (INIS)

    Nakashima, S; Dote, T; Atsuchi, M; Inoue, K

    2010-01-01

    Mixed crystals, [Fe 1-x M x (NCX) 2 (bpp) 2 ] (M=Zn, Co; X=S, Se; bpp1,3-bis(4-pyridyl)propane), had a similar structure with 2D interpenetrated structure of [Fe(NCX) 2 (bpp) 2 ]. The proportion of Fe II low-spin state in the mixed crystals of NCSe complex increased compared with that of the corresponding Fe complex, while such change in the Moessbauer spectra was not observed in the NCS complex.

  3. Synthesis of racemic, S(+)- and R(-)-N-[methyl- 3H]3,4-methylenedioxymethamphetamine

    International Nuclear Information System (INIS)

    Hashimoto, Kenji; Hirai, Katsumi; Goromaru, Tsuyoshi

    1990-01-01

    The synthesis of 3,4-methylenedioxymethampetamine (MDMA), a serotonergic neurotoxin, labeled with tritium is described. Labeling was accomplished by N-alkylation of the free base of the corresponding desmethyl compound using [ 3 H]methyl iodide. The compound was purified by preparative HPLC. The radiochemical yield was about 60% based on [ 3 H]methyl iodide. The radiochemical purity was more than 95% from HPLC and TLC. Furthermore, S(+)- and R(-)-[ 3 H]MDMA were completely separated by analytical HPLC with chiral column. (author)

  4. A Novel Strategy Towards the Asymmetric Synthesis of Orthogonally Funtionalised 2-N-Benzyl-N-α-methylbenzylamino- 5-carboxymethyl-cyclopentane-1-carboxylic acid.

    Directory of Open Access Journals (Sweden)

    Julio G. Urones

    2004-04-01

    Full Text Available The asymmetric synthesis of the orthogonally funtionalised compounds tert-butyl 2-N-benzyl-N-α-methylbenzylamino-5-methoxycarbonylmethylcyclopentane- 1-carboxylate and methyl 2-N-benzyl-N-α-methylbenzylamino-5–carboxymethylcyclo- pentane-1-carboxylate by a domino reaction of tert-butyl methyl (E,E-octa-2,6- diendioate with lithium N-α-methylbenzyl-N-benzylamide initiated by a Michael addition, subsequent 5-exo-trig intramolecular cyclisation and posterior selective hydrolysis with trifluoroacetic acid is reported.

  5. Fragrance material review on 2-methyl-4-phenyl-2-butanol.

    Science.gov (United States)

    Scognamiglio, J; Jones, L; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 2-methyl-4-phenyl-2-butanol when used as a fragrance ingredient is presented. 2-methyl-4-phenyl-2-butanol is a member of the fragrance structural group Aryl Alkyl Alcohols and is a tertiary alcohol. The AAAs are a structurally diverse class of fragrance ingredients that includes primary, secondary, and tertiary alkyl alcohols covalently bonded to an aryl (Ar) group, which may be either a substituted or unsubstituted benzene ring. The common structural element for the AAA fragrance ingredients is an alcohol group -C-(R1)(R2)OH and generically the AAA fragrances can be represented as an Ar-C-(R1)(R2)OH or Ar-Alkyl-C-(R1)(R2)OH group. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 2-methyl-4-phenyl-2-butanol were evaluated then summarized and includes physical properties, acute toxicity, skin irritation, and skin sensitization data. A safety assessment of the entire Aryl Alkyl Alcohols will be published simultaneously with this document; please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all Aryl Alkyl Alcohols in fragrances. assessment of aryl alkyl alcohols when used as fragrance ingredients. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Multipotent cholinesterase/monoamine oxidase inhibitors for the treatment of Alzheimer’s disease: design, synthesis, biochemical evaluation, ADMET, molecular modeling, and QSAR analysis of novel donepezil-pyridyl hybrids

    Directory of Open Access Journals (Sweden)

    Bautista-Aguilera OM

    2014-10-01

    Full Text Available Oscar M Bautista-Aguilera,1,* Gerard Esteban,2,* Mourad Chioua,1 Katarina Nikolic,3 Danica Agbaba,3 Ignacio Moraleda,4 Isabel Iriepa,4 Elena Soriano,5 Abdelouahid Samadi,1 Mercedes Unzeta,2 José Marco-Contelles1 1Laboratory of Medicinal Chemistry (Institute of General Organic Chemistry [IQOG], National Research Council [CSIC], Madrid, Spain; 2Department of Biochemistry and Molecular Biology, Institute of Neurosciences, Autonomous Barcelona University, Barcelona, Spain; 3Institute of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia; 4Department of Organic Chemistry, Faculty of Pharmacy, University of Alcalá, Ctra Barcelona, Alcalá de Henares, Spain; 5Synthesis, and Structure of Organic Compounds (SEPCO (IQOG, CSIC, Madrid, Spain *These authors have equally contributed to this work Abstract: The design, synthesis, and biochemical evaluation of donepezil-pyridyl hybrids (DPHs as multipotent cholinesterase (ChE and monoamine oxidase (MAO inhibitors for the potential treatment of Alzheimer’s disease (AD is reported. The 3D-quantitative structure-activity relationship study was used to define 3D-pharmacophores for inhibition of MAO A/B, acetylcholinesterase (AChE, and butyrylcholinesterase (BuChE enzymes and to design DPHs as novel multi-target drug candidates with potential impact in the therapy of AD. DPH14 (­Electrophorus electricus AChE [EeAChE]: half maximal inhibitory concentration [IC50] =1.1±0.3 nM; equine butyrylcholinesterase [eqBuChE]: IC50 =600±80 nM was 318-fold more potent for the inhibition of AChE, and 1.3-fold less potent for the inhibition of BuChE than the reference compound ASS234. DPH14 is a potent human recombinant BuChE (hBuChE inhibitor, in the same range as DPH12 or DPH16, but 13.1-fold less potent than DPH15 for the inhibition of human recombinant AChE (hAChE. Compared with donepezil, DPH14 is almost equipotent for the inhibition of hAChE, and 8.8-fold more potent for h

  7. Tetradentate N2O2 Chelated Palladium(II Complexes: Synthesis, Characterization, and Catalytic Activity towards Mizoroki-Heck Reaction of Aryl Bromides

    Directory of Open Access Journals (Sweden)

    Siti Kamilah Che Soh

    2013-01-01

    Full Text Available Four air and moisture-stable palladium(II-Schiff base complexes, N,N′-bis(α-methylsalicylidenepropane-1,3-diamine palladium(II (2a, N,N′-bis(4-methyl-α-methylsalicylidenepropane-1,3-diamine palladium(II (2b, N,N′-bis(3,5-di-tert-butylsalicylidenepropane-1,3-diamine palladium(II (2c, and N,N′-bis(4-methoxy-salicylidenepropane-1,3-diamine palladium(II (2d, have been successfully synthesised and characterised by CHN elemental analyses and conventional spectroscopic methods. These complexes were investigated as catalysts in the phosphine-free Mizoroki-Heck cross-coupling reactions of aryl bromides with methyl acrylate.

  8. Investigation of nanocomposites made with poly(methacrylic acid-co-methyl methacrylate/poly(N-vinyl-2-pyrrolidone/multi-walled carbon nanotubes

    Directory of Open Access Journals (Sweden)

    Liu Guoqin

    2014-01-01

    Full Text Available Poly(methacrylic acid-co-methyl methacrylate (P(MAA-co-MMA was prepared in the presence of poly(N-vinyl-2-pyrrolidone (PVP and multiwalled carbon nanotubes (MWNTs via ultrasonic assisted solution free radical polymerization, i.e., P(MAA-co-MMA/PVP/MWNTs nanocomposites. The morphology, glassy-state storage modulus, thermal behavior and swelling characteristics of P(MAA-co-MMA/PVP/MWNTs nanocomposites were investigated. Scanning electron micrographs (SEM revealed that MWNTs at low concentration could be uniformly dispersed into P(MAA-co-MMA/PVP blends. With increasing MWNTs weight fraction, the average glassy-state modulus, glass transition temperatures and decomposition temperature of the nanocomposites increased, but their swelling characteristics decreased.

  9. Investigation of nanocomposites made with poly(methacrylic acid-co-methyl methacrylate)/poly(N-vinyl-2-pyrrolidone)/multi-walled carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Guoqin, Liu; Wei, Miao [College of Material Science and Engineering, Henan University of Technology (China); Lin-Jian, Shangguan, E-mail: mikepolymer@126.com [School of Mechanical Engineering, North China University of Water Conservancy and Electric Power (China)

    2014-06-01

    Poly(methacrylic acid-co-methyl methacrylate) (P(MAA-co-MMA)) was prepared in the presence of poly(N-vinyl-2-pyrrolidone) (PVP) and multi-walled carbon nanotubes (MWNTs) via ultrasonic assisted solution free radical polymerization, i.e., P(MAA-co-MMA)/PVP/MWNTs nanocomposites. The morphology, glassy-state storage modulus, thermal behavior and swelling characteristics of P(MAA-co-MMA)/PVP/MWNTs nanocomposites were investigated. Scanning electron micrographs (SEM) revealed that MWNTs at low concentration could be uniformly dispersed into P(MAA-co-MMA)/PVP blends. With increasing MWNTs weight fraction, the average glassy-state modulus, glass transition temperatures and decomposition temperature of the nanocomposites increased, but their swelling characteristics decreased. (author)

  10. Different reactivities of amphetamines with N-methyl-bis(trifluoroacetamide) in heated gas chromatographic injectors.

    Science.gov (United States)

    Hidvégi, E; Hideg, Zs; Somogyi, G P

    2008-03-01

    A fast gas chromatographic mass spectrometric method has been developed earlier for the determination of amphetamine derivatives in human serum and urine. For derivatization, N-methyl-bis(trifluoroacetamide) (MBTFA) was used. Derivatization was performed using an on-line mode, since 1 microl of MBTFA and 1 microl sample extract, dissolved in toluene were injected simultaneously. In this study, the reactivity of the several amphetamine type analytes with MBTFA was investigated. MBTFA used for flash derivatization was applied undiluted on the one hand and diluted 4--4096-fold with acetonitrile on the other hand. Studying several amphetamines in the test sample spiked at the same concentrations we found that they could be divided into 3 groups based on relative target ion peak areas as a function of MBTFA dilution. Group 1, containing only primary amines showed an early increase of the relative peak areas if we increased MBTFA concentration, where group 2 (mainly N-methyl secondary amines) showed that relative peak areas started to increase intensively at higher MBTFA concentrations. Finally, MDEA as an N-ethyl secondary amine, representing group 3, showed significant increase if only slightly diluted MBTFA was used as a flash reagent. This phenomenon can be explained mainly with the less and less reactivity of amine groups in the case of groups 2 and 3, compared to group 1. These findings could help to optimise analytical methods involving flash derivatization processes.

  11. Henry's law constants and infinite dilution activity coefficients of cis-2-butene, dimethylether, chloroethane, and 1,1-difluoroethane in methanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutanol, tert-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, 3-methyl-1-butanol, and 2-methyl-2-butanol

    International Nuclear Information System (INIS)

    Miyano, Yoshimori; Kobashi, Takahiro; Shinjo, Hiroshi; Kumada, Shinya; Watanabe, Yusuke; Niya, Wataru; Tateishi, Yoko

    2006-01-01

    Henry's law constants and infinite dilution activity coefficients of cis-2-butene, dimethylether, chloroethane, and 1,1-difluoroethane in methanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutanol, tert-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, 3-methyl-1-butanol, and 2-methyl-2-butanol in the temperature range of 250 K to 330 K were measured by a gas stripping method and partial molar excess enthalpies were calculated from the activity coefficients. A rigorous formula for evaluating the Henry's law constants from the gas stripping measurements was used for the data reduction of these highly volatile mixtures. The uncertainty is about 2% for the Henry's law constants and 3% for the estimated infinite dilution activity coefficients. In the evaluation of the infinite dilution activity coefficients, the nonideality of the solute such as the fugacity coefficient and Poynting correction factor cannot be neglected, especially at higher temperatures. The estimated uncertainty of the infinite dilution activity coefficients includes 1% for nonideality

  12. Gas-phase reactions of glycine, alanine, valine and their N-methyl derivatives with the nitrosonium ion, NO+.

    Science.gov (United States)

    Freitas, M A; O'Hair, R A; Schmidt, J A; Tichy, S E; Plashko, B E; Williams, T D

    1996-10-01

    The gas-phase reactions of the nitrosonium ion, NO+ with the amino acids glycine, alanine and valine and their N-methyl derivatives were investigated under chemical ionization mass spectrometric (CIMS) conditions. Two products were observed in all cases: the formation of the iminium ion and the formation of an [M-H]+ ion. The latter product is consistent with a reaction channel involving hydride abstraction by NO+, and was confirmed by (i) examining the Ar+CI mass spectra of the same amino acids under similar source conditions and (ii) examining the unimolecular fragmentation reactions of the [M + H]+ ions of the N-nitroso-N-methyl derivatives of each of the amino acids in a tandem mass spectrometer. Further insights into the reaction of glycine with NO+ were obtained by performing ab initio calculations (at the MP2/6-31G* parallel HF/6-31G* level). These results indicate that four reactions are thermodynamically viable for glycine: (i) hydride abstraction; (ii) iminium ion formation (with concomitant loss of HONO and CO); (iii) diazonium ion formation; and (iv) diazonium ion formation followed by loss of N2. Possible reasons why reactions (iii) and (iv) are not observed are discussed, and comparisons with solution reactivity and the gas-phase reactivity of NO+ are also made.

  13. PEGylated N-methyl-S-methyl dithiocarbazate as a new reagent for the high-yield preparation of nitrido Tc-99m and Re-188 radiopharmaceuticals

    Energy Technology Data Exchange (ETDEWEB)

    Boschi, Alessandra, E-mail: alessandra.boschi@unife.i [Laboratory of Nuclear Medicine, Department of Radiological Sciences, University of Ferrara, 44100 Ferrara (Italy); Massi, Alessandro [Department of Chemistry, University of Ferrara, 44100 Ferrara (Italy); Uccelli, Licia; Pasquali, Micol; Duatti, Adriano [Laboratory of Nuclear Medicine, Department of Radiological Sciences, University of Ferrara, 44100 Ferrara (Italy)

    2010-11-15

    A novel nitrido nitrogen atom donor for the preparation of {sup 99m}Tc and {sup 188}Re radiopharmaceuticals containing a metal-nitrogen multiple bond is presented. HO{sub 2}C-PEG{sub 600}-DTCZ was obtained by conjugation of N-methyl-S-methyl dithiocarbazate [H{sub 2}N-N(CH{sub 3})-C({identical_to}S)SCH{sub 3}, HDTCZ] with polyethylene glycol 600 (PEG{sub 600}). Asymmetrical heterocomplexes of the type [M(N)(PNP)(B)]{sup 0/+} (M={sup 99m}Tc, {sup 188}Re; PNP=diphosphine ligands, B=DBODC, DEDC, NSH, H{sub 2}OS, CysNAc, HDTCZ) and symmetrical nitride compounds of the type [M(N)(L){sub 2}] (L=DEDC, DPDC) have been prepared in high yield by using the newly designed nitride nitrogen atom donor HO{sub 2}C-PEG{sub 600}-DTCZ. A two-step procedure was applied for preparing the above symmetrical and asymmetrical complexes. The first step involved the preliminary formation of a mixture of nitride Tc-99m or Re-188 precursors, which contained the [M{identical_to}N]{sup 2+} core, through reduction of generator-eluted {sup 99m}Tc-pertechnetate or {sup 188}Re-perrhenate with thin (II) chloride in the presence of HO{sub 2}C-PEG{sub 600}-DTCZ. In the second step, the intermediate mixture was converted either in the final mixed asymmetrical complex by the simultaneous addition of diphosphine ligand and the suitable bidentate ligand B, or in the final symmetrical complex by the only addition of the bidentate ligand L. It was also demonstrated that the novel water-soluble nitride nitrogen atom donor HO{sub 2}C-PEG{sub 600}-DTCZ did not show coordinating properties toward the M{identical_to}N ({sup 99m}Tc, {sup 188}Re) core. Biodistribution studies in rats of the hitherto unreported [{sup 99m}Tc(N)(PNP{sub 3})DTCZ]{sup +} and [{sup 99m}Tc(N)(PNP{sub 5})DTCZ]{sup +} complexes showed that they selectively localize in the myocardium of rats with a favourable heart-to-lung and heart-to-liver uptake ratios. In particular, the heart-to-lung and heart-to-liver uptake ratios dramatically

  14. Synthesis of (+-)-[1,1'-15N2, 2'-13C]-trans-3'-methylnicotine

    International Nuclear Information System (INIS)

    Sirimanne, S.R.; Maggio, V.L.; Patterson, D.G. Jr.

    1992-01-01

    The synthesis of (±)- [1,1'- 15 N 2 , 2'- 13 C]-trans-3'-methylnicotine is reported. 15 N-3-Bromopyridine obtained from bromination of pyridine was formylated with nBuLi/[carbonyl- 13 C]-methyl formate. The resulting 15 n-Pyridine-3-[ 13 C-carbonyl]-carboxaldehyde was reacted with 15 N-methylamine and then the resulting Schiff's base was condensed with succinic anhydride to give (±)- [1,1'- 15 N 2 , 5'- 13 C]-trans-4'-carboxycotinine. Reduction with lithium aluminum hydride and mesylation followed by reduction with Zn/NaI gave (±)-[1,1'- 15 N 2 , 2'- 13 C]-trans-3'-methylnicotine. (Author)

  15. Effects of TET2 mutations on DNA methylation in chronic myelomonocytic leukemia

    Science.gov (United States)

    TET2 enzymatically converts 5-methyl-cytosine to 5-hydroxymethyl-cytosine, possibly leading to loss of DNA methylation. TET2 mutations are common in myeloid leukemia and were proposed to contribute to leukemogenesis through DNA methylation. To expand on this concept, we studied chronic myelomonocyti...

  16. Determination of N-vinyl-2-pyrrolidone and N-methyl-2-pyrrolidone in drugs using polypyrrole-based headspace solid-phase microextraction and gas chromatography-nitrogen-phosphorous detection.

    Science.gov (United States)

    Mehdinia, Ali; Ghassempour, Alireza; Rafati, Hasan; Heydari, Rouhollah

    2007-03-21

    A headspace solid-phase microextraction and gas chromatography-nitrogen-phosphorous detection (HS-SPME-GC-NPD) method using polypyrrole (PPy) fibers has been introduced to determine two derivatives of pyrrolidone; N-vinyl-2-pyrrolidone (NVP) and N-methyl-2-pyrrolidone (NMP). Two types of PPy fibers, prepared using organic and aqueous media, were compared in terms of extraction efficiency and thermal stability. It was found that PPy film prepared using organic medium (i.e. acetonitrile) had higher extraction efficiency and more thermal stability compared to the film prepared in aqueous medium. To enhance the sensitivity of HS-SPME, the effects of pH, ionic strength, extraction time, extraction temperature and the headspace volume on the extraction efficiency were optimized. Using the results of this research, high sensitivity and selectivity had been achieved due to the combination of the high extraction efficiency of PPy film prepared in organic medium and the high sensitivity and selectivity of nitrogen-phosphorous detection. Linear range of the analytes was found to be between 1.0 and 1000 microg L(-1) with regression coefficients (R(2)) of 0.998 and 0.997 for NVP and NMP, consequently. Limits of detection (LODs) were 0.074 and 0.081 microg L(-1) for NVP and NMP, respectively. Relative standard deviation (R.S.D.) for five replications of analyses was found to be less than 6.0%. In real samples the mean recoveries were 94.81% and 94.15% for NVP and NMP, respectively. The results demonstrated the suitability of the HS-SPME technique for analyzing NVP and NMP in two different pharmaceutical matrices. In addition, the method was used for simultaneous detection of NVP, 2-pyrrolidone (2-Pyr), gamma-butyrolactone (GBL) and ethanolamine (EA) compounds.

  17. 40 CFR 721.9920 - Urea, (hexahydro-6-methyl-2-oxopyrimidinyl)-.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Urea, (hexahydro-6-methyl-2... Specific Chemical Substances § 721.9920 Urea, (hexahydro-6-methyl-2-oxopyrimidinyl)-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance urea, (hexahydro-6...

  18. Fatal intoxication with 3-methyl-N-methylcathinone (3-MMC) and 5-(2-aminopropyl)benzofuran (5-APB).

    Science.gov (United States)

    Adamowicz, Piotr; Zuba, Dariusz; Byrska, Bogumiła

    2014-12-01

    The emergence of a large number of new psychoactive substances (NPSs) in recent years poses a serious problem to clinical and forensic toxicologists. Here we report a patient who administrated ca. 500mg of 3-MMC (3-methyl-N-methylcathinone) and 400mg of 5-APB (5-(2-aminopropyl)benzofuran) in combination with 80g of ethyl alcohol. The clinical manifestations included agitation, seizures, hypertension, tachycardia, hyperthermia and bradycardia. The patient did not recover and died around 4h after the use of drugs. The cause of death was acute cardiovascular collapse that occurred following mixed intoxication with NPSs and alcohol. Toxicological analysis of post-mortem blood revealed 3-MMC and 5-APB in concentrations of 1.6μg/mL and 5.6μg/mL, respectively. Moreover, the serum alcohol concentration was 1.4g/L in ante-mortem sample collected 1h after admission to the hospital. This is the first report on blood concentration of 3-MMC and 5-APB in fatal intoxication. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  19. Inhibition of TNFα-induced adhesion molecule expression by (Z)-(S)-9-octadecenamide, N-(2-hydroxyethyl,1-methyl).

    Science.gov (United States)

    Chen, Caixia; Jin, Xin; Meng, Xianglan; Zheng, Chengwei; Shen, Yanhui; Wang, Yiqing

    2011-06-25

    Inflammation is a primary event in atherogenesis. Oleoylethanolamide (OEA), a naturally occurring fatty-acid ethanolamide, lowers lipid levels in liver and blood through activation of the nuclear receptor, peroxisome proliferator-activated receptor-alpha (PPARα). We designed and synthesized (Z)-(S)-9-octadecenamide, N-(2-hydroxyethyl, 1-methyl) (OPA), an OEA analog. The present study investigated the effect of OPA on the expression of adhesion molecules in human umbilical vein endothelial cells (HUVEC). OPA inhibited expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) stimulated by Tumor Necrosis Factor-α (TNF-α) via activation of PPARα. This inhibition of VCAM-1 and ICAM-1 expression decreased adhesion of monocyte-like cells to stimulated endothelial cells. These results demonstrate that OPA may have anti-inflammatory properties. Our results thus provide new insights into possible future therapeutic approaches to the treatment of atherosclerosis. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Adenine N6-methylation in diverse fungi

    NARCIS (Netherlands)

    Seidl, Michael F.

    2017-01-01

    A DNA modification - methylation of cytosines and adenines - has important roles in diverse processes such as regulation of gene expression and genome stability, yet until recently adenine methylation had been considered to be only a hallmark of prokaryotes. A new study identifies abundant

  1. Role Of Shark Cartilage In Reducing Changes In Gene Expression Of Some Enzymes Induced By N-Nitroso-N-Methyl Urea In Prostate Of Irradiated Rats

    International Nuclear Information System (INIS)

    ELMAGHRABY, T.; YACOUB, S.; IBRAHIM, N.K.

    2009-01-01

    There is overwhelming evidence to indicate that free radicals cause oxidative damage to lipids, proteins and nucleic acids and are involved in the pathogenesis of several diseases. Therefore, antioxidants, which can neutralize free radicals, may be of central importance in the prevention of these diseases. Recent studies demonstrated the role of shark cartilage in protecting cells against reactive oxygen species induced DNA damage and mutagenesis. Reactive oxygen species and other free radicals are known to be the mediators of phenotypic and genotypic changes that lead from mutation to neoplasia. There are some primary antioxidants such as glutathione peroxidase (GSHPx), glutathione-S-transferase (GST-π) and super oxide dismutase (SOD), which protects against cellular and molecular damage caused by the reactive oxygen metabolites (ROMs).In this study, the effect of shark cartilage against the N-nitroso-N-methyl urea + testosterone and/or gamma radiation-induced mutagens and carcinogens in rat prostate were investigated.The data showed significant decrease in gene expression of manganese superoxide dismutase (Mn-SOD), glutathione peroxidase 1 (GSHPx1) , enzyme activities of total superoxide dismutase (SOD) and glutathione peroxidase (GSHPx) and non-significant increase in glutathione-S-transferase (GST-π) in N-nitroso-N-methyl urea + testosterone, N-nitroso-N-methyl urea + testosterone + gamma radiation groups as compared to control group.The results revealed that shark cartilage administration afford a significant protective effect against N-nitroso-N-methyl urea + testosterone and/or gamma radiation- induced oxidative injury.

  2. Comparing Cr, and N only doping with (Cr,N)-codoping for enhancing visible light reactivity of TiO2

    International Nuclear Information System (INIS)

    Li, Yuan; Wang, Wei; Qiu, Xiaofeng; Meyer, Harry M. III; Paranthaman, Mariappan Parans; Eres, Gyula; Zhang, Zhenyu; Gu, Baohua

    2011-01-01

    The photoreactivity of titania (TiO2) nanoclusters with varying levels of N or Cr-doping, or (Cr,N)-codoping, was systematically investigated using photodegradation of methyl orange in aqueous suspensions. The shifting of the TiO2 absorption edge into the visible spectral region that is primarily attributable to band gap narrowing was found to be a reliable metric for estimating the photoreactivity of the doped nanoclusters. Compared to the weak response with undoped and N-doped TiO2, Cr-doping and (Cr, N)-codoping were found to significantly enhance photodegradation of methyl orange under visible light. The initial reaction rates increase from about 0 to above 1.6 10-2 min-1 when the doping concentration of Cr in TiO2 increases from 0 to 5%. In stark contrast, under UV irradiation, doping is not only ineffective but detrimental to the photoreactivity, and all doping including N or Cr only and (Cr, N)-codoping were found to reduce photoreactivity.

  3. 78 FR 32157 - Methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate; Exemption from the Requirement of a Tolerance

    Science.gov (United States)

    2013-05-29

    ... study showed no treatment- related effects on mating or fertility. There were no treatment-related... a petition to EPA under the Federal Food, Drug, and Cosmetic Act (FFDCA), requesting establishment... received and the nature of the adverse effects caused by methyl 5-(dimethylamino)-2-methyl-5- oxopentanoate...

  4. Synthesis, characterization and reactivity of oxomolybdenum(V) complexes with ONS and NNS donors

    International Nuclear Information System (INIS)

    Bhattacharjee, Samiran; Bhattacharyya, Ramgopal

    1995-01-01

    The monomeric oxomolybdenum(V) complexes, (MoOLCl 2 ) 1a-1d (HL=S-benzyl/methyl 3-(2-pyridyl)methylenedithiocarbazate (1a and 1b), or N-methyl-S-benzyl/methyl 3-(2-hydroxyphenyl)methylenedithiocarbazate (1c and 1d) are synthesized by the reaction of MoOCl 5 2- with HL ligands. All these complexes show magnetic moment of about 1.7 B.M. The complexes, 1a and 1b, exhibit rhombic g-tensor anisotropy (like xanthine oxidase) whilst 1c and 1d show axial spectrum. The above complexes undergo irreversible electrochemical reduction furnishing Mo(IV) species and the potentials are dependent on the S-substituents. Reactions of MoOX 5 2- (X=Cl or Br) with H 2 L 1 (H 2 L 1 =S-methyl 3-(5-R-2-hydroxyphenyl)methylenedithiocarbazate) (R=H, CH 3 , Cl, Br) produce complexes of thiolatobridged dimers, (Mo 2 O 2 L 2 1 X 2 ), which show sub-normal magnetic moments at room temperature. The metal centred irreversible oxidation and reduction of these complexes show expected dependence on the R-substituents of the salicyl phenyl ring of the ligands. (author). 40 refs., 2 figs., 3 tabs

  5. Synthesis and photoluminescence properties of silver(I) complexes based on N-benzoyl-L-glutamic acid and N-donor ligands with different flexibility

    Science.gov (United States)

    Yan, Ming-Jie; Feng, Qi; Song, Hui-Hua

    2016-05-01

    By changing the N-donor ancillary ligand, three novel silver (I) complexes {[Ag(HbzgluO) (4,4‧-bipy)]·H2O}n (1), {[Ag2(HbzgluO)2 (bpe)22H2O}n (2) and {[Ag(HbzgluO)(bpp)]·2H2O}n (3) (H2bzgluO = N-benzoyl-L-glutamic acid, 4,4‧-bipy = 4,4ˊ-bipyridine, bpe = 1,2-di(4-pyridyl)ethane, bpp = 1,3-di(4-pyridyl)propane) were synthesized. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric analyses (TGA). In this study, the N-donor ligands are changed from rigidity (4,4‧-bipy), quasi-flexibility (bpe) to flexibility (bpp), the structures of complexes also change. Complex 1 features a 1D chain structure which is further linked together to construct a 2D supramolecular structure through hydrogen bonds. Complex 2 is a 1D double-chains configuration which eventually forms a 3D supramolecular network via hydrogen bonding interactions. Whereas, complex 3 exhibits a 2D pleated grid structure which is linked by hydrogen bonding interactions into a 3D supramolecular network. The present observations demonstrate that the modulation of coordination polymers with different structures can accomplish by changing the spacer length of N-donor ligands. In addition, the solid-state circular dichroism (CD) spectra indicated that compound 2 exhibited negative cotton effect which originated from the chiral ligands H2bzgluO and the solid-state fluorescence spectra of the three complexes demonstrated the auxiliary ligands have influence on the photoluminescence properties of the complexes.

  6. Regioselectivity in the Thermal Rearrangement of Unsymmetrical 4-Methyl-4H-1,2,4-triazoles to 1-Methyl-1H-1,2,4-triazoles

    Directory of Open Access Journals (Sweden)

    Per H.J. Carlsen

    2001-11-01

    Full Text Available The rearrangement of 4-methyl-3,5-diaryl-4H-1,2,4-triazoles to the corresponding 1-methyl-3,5-diaryl-1H-1,2,4-triazoles showed regioselectivity comparable to that observed for the alkylation of 3,5-diaryl-1H-1,2,4-triazoles. This lends support to a proposed mechanism for the rearrangement that involves consecutive nucleophilic displacements steps.

  7. A new (4, 6)-connected Cu(I) coordination polymer based on rare tetranuclear [Cu4I2] clusters: Synthesis, crystal structure, luminescent and photocatalytic properties

    Science.gov (United States)

    Cui, Li-Jing; Liu, Chun-Yan; Bian, Ming; Yu, Li-Jun

    2018-03-01

    A new Cu(I) coordination polymer, namely [Cu5I3(L)2]n (1 HL = 3-(4-pyridyl)-5-(3-pyridyl)-1,2,4-triazolyl), was solvothermally synthesized using CuI, HL and NaI as the starting materials. Single crystal X-ray structural analysis shows that compound 1 features a (4, 6)-connected 3D framework employing rare tetranuclear [Cu4I2] clusters as building subunits. It exhibits intense metal-to-ligand luminescence and excellent photocatalytic activity on degradation of methylene blue (MB).

  8. Synthesis, Structure, and Cyclocondensation of the 4,4,4-Trifluoro-3,3-dihydroxy-2-methyl-1-(thien-2-yl-1-butanone with Hydroxylamine and Hydrazine

    Directory of Open Access Journals (Sweden)

    Alex F. C. Flores

    2018-01-01

    Full Text Available The synthesis of 4,4,4-trifluoro-3,3-dihydroxy-2-methyl-1-(thien-2-ylbutan-1-one (3 through acylation of 1,1-dimethoxy-1-(thien-2-ylpropane (1 with trifluoroacetic anhydride and its reactions with hydroxylamine and hydrazine was investigated. X-ray structural analysis of new trifluoromethyl-substituted dielectrophile 3 revealed that this hydrate exists as a racemate with inter- and intramolecular O-H·O bonds. The crystal structure shows alignment along axis b of pair molecules with the same configuration of the O2-H·O1 bond. For 5(3-trifluoromethyl-4-methyl-3(5-(thien-2-yl-1H-pyrazole (4, obtained via cyclocondensation of precursor 2 and hydrazine hydrochloride, X-ray structural analysis indicated that its rings are almost planar (torsion angle N2-C5-C6-C7–5.4° and that S1 at the thienyl moiety is anti-periplanar to N2 (torsion angle N2-C5-C6-S1 176.01; no disorder effect was observed for the thienyl ring.

  9. Crystal structure of 2-bromo-3-dimethylamino-N,N,N′,N′,4-pentamethyl-4-(trimethylsilyloxypent-2-eneamidinium bromide

    Directory of Open Access Journals (Sweden)

    Ioannis Tiritiris

    2015-12-01

    Full Text Available The reaction of the orthoamide 1,1,1-tris(dimethylamino-4-methyl-4-(trimethylsilyloxypent-2-yne with bromine in benzene, yields the title salt, C15H33BrN3OSi+·Br−. The C—N bond lengths in the amidinium unit are 1.319 (6 and 1.333 (6 Å, indicating double-bond character, pointing towards charge delocalization within the NCN plane. The C—Br bond length of 1.926 (5 Å is characteristic for a C—Br single bond. Additionally, there is a bromine–bromine interaction [3.229 (3 Å] present involving the anion and cation. In the crystal, weak C—H...Br interactions between the methyl H atoms of the cation and the bromide ions are present.

  10. Crystal structure of 2-amino-4-methyl-pyridin-1-ium (2R,3R)-3-carb-oxy-2,3-di-hydroxy-propano-ate monohydrate.

    Science.gov (United States)

    Jovita, J V; Sathya, S; Usha, G; Vasanthi, R; Ramanand, A

    2014-09-01

    The title mol-ecular salt, C6H9N2 (+)·C4H5O6 (-)·H2O, crystallized with two 2-amino-4-methyl-pyridin-1-ium cations, two l-(+)-tartaric acid monoanions [systematic name: (2R,3R)-3-carb-oxy-2,3-di-hydroxy-propano-ate] and two water mol-ecules in the asymmetric unit. In the crystal, the cations, anions and water mol-ecules are linked via a number of O-H⋯O and N-H⋯O hydrogen bonds, and a C-H⋯O hydrogen bond, forming a three-dimensional structure.

  11. Regiospecific synthesis of new fatty N-acyl trihalomethylated pyrazoline derivatives from fatty acid methyl esters (FAMEs)

    Energy Technology Data Exchange (ETDEWEB)

    Beck, Paulo; Santos, Juliane M. dos; D' Oca, Marcelo G. M.; Piovesan, Luciana A., E-mail: lpiovesan@gmail.com [Universidade Federal do Rio Grande (UFRS), RS (Brazil). Escola de Quimica e Alimentos; Kuhn, Bruna L.; Moreira, Dayse N.; Flores, Alex F.C.; Martins, Marcos A.P. [Universidade Federal de Santa Maria (UFSM), RS (Brazil). Dept. de Quimica

    2012-11-15

    A series of new fatty N-acyl trihalomethylated pyrazoline derivatives from fatty acid methyl esters was synthesized by the cyclo condensation of respective fatty hydrazides with 4-alkoxy- 1,1,1-trial omethyl-3-alquen-2-ones. Efficient and regiospecific cyclizations catalyzed by BF{sub 3}-MeOH gave the desired products in good to excellent yields and at high purity. (author)

  12. Complementary vapor pressure data for 2-methyl-1-propanol and 3-methyl-1-butanol at a pressure range of (15 to 177) kPa

    Energy Technology Data Exchange (ETDEWEB)

    Bejarano, Arturo; Quezada, Nathalie [Departamento de Ingenieria Quimica y Ambiental, Universidad Tecnica Federico Santa Maria, Avda. Espana 1680, Valparaiso (Chile); Fuente, Juan C. de la [Departamento de Ingenieria Quimica y Ambiental, Universidad Tecnica Federico Santa Maria, Avda. Espana 1680, Valparaiso (Chile)], E-mail: juan.delafuente@usm.cl

    2009-09-15

    The vapor pressure of pure 2-methyl-1-propanol and 3-methyl-1-butanol, components called congeners that are present in aroma of wine, pisco, and other alcoholic beverages, were measured with a dynamic recirculation apparatus at a pressure range of (15 to 177) kPa with an estimated uncertainty <0.2%. The measurements were performed at temperature ranges of (337 to 392) K for 2-methyl-1-propanol and (358 to 422) K for 3-methyl-1-butanol. Data were correlated using a Wagner-type equation with standard deviations of 0.09 kPa for the vapor pressure of 2-methyl-1-propanol and 0.21 kPa for 3-methyl-1-butanol. The experimental data and correlation were compared with data selected from the literature.

  13. Spin state of mixed crystals of iron with zinc or cobalt for the assembled complexes bridged by 1,3-bis(4-pyridyl)propanes

    Energy Technology Data Exchange (ETDEWEB)

    Nakashima, S [Natural Science Center for Basic Research and Development, Hiroshima University, Kagamiyama, Higashi-Hiroshima 739-8526 (Japan); Dote, T; Atsuchi, M; Inoue, K, E-mail: snaka@hiroshima-u.ac.j [Graduate School of Science, Hiroshima University, Kagamiyama, Higashi-Hiroshima 739-8526 (Japan)

    2010-03-01

    Mixed crystals, [Fe{sub 1-x}M{sub x}(NCX){sub 2}(bpp){sub 2}] (M=Zn, Co; X=S, Se; bpp1,3-bis(4-pyridyl)propane), had a similar structure with 2D interpenetrated structure of [Fe(NCX){sub 2}(bpp){sub 2}]. The proportion of Fe{sup II} low-spin state in the mixed crystals of NCSe complex increased compared with that of the corresponding Fe complex, while such change in the Moessbauer spectra was not observed in the NCS complex.

  14. Comparative studies with n-methyl-2-pyrrolidone and furfural as solvents for extraction of lube distillates

    Energy Technology Data Exchange (ETDEWEB)

    Krishna, R.; Singh, H.; Kishore, K.; Choudhary, G.S.; Kaushik, R.S.

    Solvent extraction of spindle raw lube distillate from Oman crude using n-methyl pyrrolidone (NMP) containing 1.5 wt.% water has been studied using a six-stage all-glass mixer-settler. Results of three operating temperatures with NMP are reported. A 65-55/sup 0/C extraction temperature appears to be most appropriate for this stock. Data obtained at this temperature have been compared with those for furfural on the basis of phase boundary curves, extraction and lube refining indices and selectivity. Comparison of the results shows NMP to be more selective as far as raffinate yield is concerned. It requires lower operating solvent-to-feed ratios and lower temperatures. 14 refs.

  15. Redetermination of 2-methyl-4-nitropyridine N-oxide

    Directory of Open Access Journals (Sweden)

    Max Peukert

    2014-04-01

    Full Text Available An improved crystal structure of the title compound, C6H6N2O3, is reported. The structure, previously solved [Li et al. (1987. Jiegou Huaxue (Chin. J. Struct. Chem., 6, 20–24] in the orthorhombic space group Pca21 and refined to R = 0.067, has been solved in the orthorhombic space group Pbcm with data of enhanced quality, giving an improved structure (R = 0.0485. The molecule adopts a planar conformation with all atoms lying on a mirror plane. The crystal structure is composed of molecular sheets extending parallel to the ab plane and connected via C—H...O contacts involving ring H atoms and O atoms of the N-oxide and nitro groups, while van der Waals forces consolidate the stacking of the layers.

  16. Role of N-Donor Sterics on the Coordination Environment and Dimensionality of Uranyl Thiophenedicarboxylate Coordination Polymers

    Energy Technology Data Exchange (ETDEWEB)

    Thangavelu, Sonia G. [Department; Butcher, Ray J. [Department; Cahill, Christopher L. [Department

    2015-06-09

    Thiophene 2,5-dicarboxylic acid (TDC) was reacted with uranyl acetate dihydrate and one (or none) of six N-donor chelating ligands (2,2'-bipyridine (BPY), 4,4'-dimethyl-2,2'-bipyridine (4-MeBPY), 5,5'-dimethyl-2,2'-bipyridine (5-MeBPY), 6,6'-dimethyl-2,2'-bipyridine (6-MeBPY), 4,4',6,6'-tetramethyl-2,2'-bipyridine (4,6-MeBPY), and tetrakis(2-pyridyl)pyrazine (TPPZ) to result in the crystallization of seven uranyl coordination polymers, which were characterized by their crystal structures and luminescence properties. The seven coordination polymers, Na2[(UO2)2(C6H2O4S)3]·4H2O (1), [(UO2)4(C6H2O4S)5(C10H8N2)2]·C10H10N2·3H2O (2), [(UO2)(C6H2O4S)(C12H12N3)] (3), [(UO2)(C6H2O4S)(C12H12N3)]·H2O (4), [(UO2)2(C6H2O4S)3]·(C12H14N2)·5H2O (5), [(UO2)3(CH3CO2)(C6H2O4S)4](C14H17N2)3·(C14H16N2)·H2O (6), and [(UO2)2(C6H2O4S)3](C24H18N6) (7), consist of either uranyl hexagonal bipyramidal or pentagonal bipyramidal coordination geometries. In all structures, structural variations in the local and global structures of 1–7 are influenced by the positions (or number) of methyl groups or pyridyl rings on the N-donor species, thus resulting in a wide diversity of structures ranging from single chains, double chains, or 2-D sheets. Direct coordination of N-donor ligands to uranyl centers is observed in the chain structures of 2–4 using BPY, 4-MeBPY, and 5-MeBPY, whereas the N-donor species participate as guests (as either neutral or charge balancing species) in the chain and sheet structures of 5–7 using 6-MeBPY, 4,6-MeBPY, and TPPZ, respectively. Compound 1 is the only structure that does not contain any N-donor ligands and thus crystallizes as a 2-D interpenetrating sheet. The luminescent properties of 1–7 are influenced by the direct coordination or noncoordination of N-donor species to uranyl centers. Compounds 2–4 exhibit typical UO22+ emission upon direct coordination of N-donors, but its absence is observed in 1

  17. Holocaust Exposure Induced Intergenerational Effects on FKBP5 Methylation.

    Science.gov (United States)

    Yehuda, Rachel; Daskalakis, Nikolaos P; Bierer, Linda M; Bader, Heather N; Klengel, Torsten; Holsboer, Florian; Binder, Elisabeth B

    2016-09-01

    The involvement of epigenetic mechanisms in intergenerational transmission of stress effects has been demonstrated in animals but not in humans. Cytosine methylation within the gene encoding for FK506 binding protein 5 (FKBP5) was measured in Holocaust survivors (n = 32), their adult offspring (n = 22), and demographically comparable parent (n = 8) and offspring (n = 9) control subjects, respectively. Cytosine-phosphate-guanine sites for analysis were chosen based on their spatial proximity to the intron 7 glucocorticoid response elements. Holocaust exposure had an effect on FKBP5 methylation that was observed in exposed parents as well in their offspring. These effects were observed at bin 3/site 6. Interestingly, in Holocaust survivors, methylation at this site was higher in comparison with control subjects, whereas in Holocaust offspring, methylation was lower. Methylation levels for exposed parents and their offspring were significantly correlated. In contrast to the findings at bin 3/site 6, offspring methylation at bin 2/sites 3 to 5 was associated with childhood physical and sexual abuse in interaction with an FKBP5 risk allele previously associated with vulnerability to psychological consequences of childhood adversity. The findings suggest the possibility of site specificity to environmental influences, as sites in bins 3 and 2 were differentially associated with parental trauma and the offspring's own childhood trauma, respectively. FKBP5 methylation averaged across the three bins examined was associated with wake-up cortisol levels, indicating functional relevance of the methylation measures. This is the first demonstration of an association of preconception parental trauma with epigenetic alterations that is evident in both exposed parent and offspring, providing potential insight into how severe psychophysiological trauma can have intergenerational effects. Published by Elsevier Inc.

  18. Synthesis of 3-substituted 5-arylidene-1-methyl-2-thiohydantoins under microwave irradiation

    DEFF Research Database (Denmark)

    Khodari, A.I.; Nielsen, John

    2002-01-01

    A mono-modal microwave oven was used to expedite the synthesis of small libraries of 3-substituted 1-methyl-2-thiohydantoins and 3-substituted 5-arylidene-1-methyl-2-thiohydantoins. In comparison with the traditional reflux methods, similar or higher yields were obtained.......A mono-modal microwave oven was used to expedite the synthesis of small libraries of 3-substituted 1-methyl-2-thiohydantoins and 3-substituted 5-arylidene-1-methyl-2-thiohydantoins. In comparison with the traditional reflux methods, similar or higher yields were obtained....

  19. DNA methylation modulates H19 and IGF2 expression in porcine female eye

    Directory of Open Access Journals (Sweden)

    Dongxu Wang

    2017-03-01

    Full Text Available Abstract The sexually dimorphic expression of H19/IGF2 is evolutionarily conserved. To investigate whether the expression of H19/IGF2 in the female porcine eye is sex-dependent, gene expression and methylation status were evaluated using quantitative real-time PCR (qPCR and bisulfite sequencing PCR (BSP. We hypothesized that H19/IGF2 might exhibit a different DNA methylation status in the female eye. In order to evaluate our hypothesis, parthenogenetic (PA cells were used for analysis by qPCR and BSP. Our results showed that H19 and IGF2 were over-expressed in the female eye compared with the male eye (3-fold and 2-fold, respectively. We observed a normal monoallelic methylation pattern for H19 differentially methylated regions (DMRs. Compared with H19 DMRs, IGF2 DMRs showed a different methylation pattern in the eye. Taken together, these results suggest that elevated expression of H19/IGF2 is caused by a specific chromatin structure that is regulated by the DNA methylation status of IGF2 DMRs in the female eye.

  20. DNA methylation modulates H19 and IGF2 expression in porcine female eye

    Science.gov (United States)

    Wang, Dongxu; Wang, Guodong; Yang, Hao; Liu, Haibo; Li, Cuie; Li, Xiaolan; Lin, Chao; Song, Yuning; Li, Zhanjun; Liu, Dianfeng

    2017-01-01

    Abstract The sexually dimorphic expression of H19/IGF2 is evolutionarily conserved. To investigate whether the expression of H19/IGF2 in the female porcine eye is sex-dependent, gene expression and methylation status were evaluated using quantitative real-time PCR (qPCR) and bisulfite sequencing PCR (BSP). We hypothesized that H19/IGF2 might exhibit a different DNA methylation status in the female eye. In order to evaluate our hypothesis, parthenogenetic (PA) cells were used for analysis by qPCR and BSP. Our results showed that H19 and IGF2 were over-expressed in the female eye compared with the male eye (3-fold and 2-fold, respectively). We observed a normal monoallelic methylation pattern for H19 differentially methylated regions (DMRs). Compared with H19 DMRs, IGF2 DMRs showed a different methylation pattern in the eye. Taken together, these results suggest that elevated expression of H19/IGF2 is caused by a specific chromatin structure that is regulated by the DNA methylation status of IGF2 DMRs in the female eye. PMID:28266684