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131.
Il’yas S. Nizamov Ilnar D. Nizamov Farid D. Yambushev Olga V. Bolshakova Gulnur G. Sergeenko Vladimir F. Mironov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1436-1442
Abstract The reactions of geraniol, nerol, and linalool with N,N-diethylamido O,O-propylenephosphite and diethyl chlorophosphite were studied. On the basis of these studies, new dienyl diprenoid phosphite esters were obtained. GRAPHICAL ABSTRACT 相似文献
132.
Dmitry V. Pankratov Yulia S. Zeifman Olga V. Morozova Galina P. Shumakovich Irina S. Vasil'eva Sergey Shleev Vladimir O. Popov Alexander I. Yaropolov 《Electroanalysis》2013,25(5):1143-1149
14 Single‐ and multi‐walled carbon nanotubes from different sources were characterized in detail, and the characteristics obtained were carefully analyzed. The carbon material with the highest capacitance, and also other superior properties (“Taunit‐M” from “NanoTechCenter”, Russia), was chosen for further modification and fabrication of buckypaper based electrodes. These electrodes were biomodified with plant and fungal laccases, as well as fungal bilirubin oxidase. The designed biocathodes were investigated in simple buffers and also in a complex physiological fluid (human serum). Biocathodes based on immobilized fungal laccase were bioelectrocatalytically inactive in chloride containing media at neutral pH. In spite of the quite high current densities realized using biodevices based on plant laccase and fungal bilirubin oxidase, the limited thermal stability of the enzymes renders the biocathodes inadequate for practical applications in implanted situations. 相似文献
133.
Luba Ignatovich Olga Starkova Vitalijs Romanovs Ilze Sleiksha Irina Shestakova Jury Popelis Edmunds Lukevics 《Comptes Rendus Chimie》2013,16(6):621-627
The reaction of 1,2-phenylenediamine with a variety of silicon- or germanium-containing 2-furaldehydes or 2-thienylcarbaldehydes in DMFA gave the corresponding benzimidazole derivatives in moderate yields (36–49%) in the presence of sodium hydrogen sulfite. As a result, a new series of silyl, germyl substituted hetarylbenzimidazoles were synthesized and their in vitro cytotoxicity was studied. The quaternisation of N-substituted benzimidazoles by heating with various alkyl, allyl and propargyl chlorides and bromides leads to the formation of benzimidazolinium salts. Potential cytotoxic activity of synthesized new benzimidazoles and benzimidazolinium salts was tested in vitro on two monolayer tumour cell lines: MG-22A (mouse hepatoma), HT-1080 (human fibrosarcoma) and normal mouse fibroblasts (NIH 3T3) and compared with corresponding benzimidazoles. 相似文献
134.
Olga M. Nazarenko Eduard B. Rusanov Alexander N. Chernega Konstantin V. Domasevitch 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(3):232-236
In poly[[bis(μ‐4,4′‐bi‐1H‐pyrazole‐κ2N2:N2′)bis(3‐carboxyadamantane‐1‐carboxylato‐κO1)cobalt(II)] dihydrate], {[Co(C12H15O4)2(C6H6N4)2]·2H2O}n, (I), the Co2+ cation lies on an inversion centre and the 4,4′‐bipyrazole (4,4′‐bpz) ligands are also situated across centres of inversion. In its non‐isomorphous cadmium analogue, {[Cd(C12H15O4)2(C6H6N4)2]·2H2O}n, (II), the Cd2+ cation lies on a twofold axis. In both compounds, the metal cations adopt an octahedral coordination, with four pyrazole N atoms in the equatorial plane [Co—N = 2.156 (2) and 2.162 (2) Å; Cd—N = 2.298 (2) and 2.321 (2) Å] and two axial carboxylate O atoms [Co—O = 2.1547 (18) Å and Cd—O = 2.347 (2) Å]. In both structures, interligand hydrogen bonding [N...O = 2.682 (3)–2.819 (3) Å] is essential for stabilization of the MN4O2 environment with its unusually high (for bulky adamantanecarboxylates) number of coordinated N‐donor co‐ligands. The compounds adopt two‐dimensional coordination connectivities and exist as square‐grid [M(4,4′‐bpz)2]n networks accommodating monodentate carboxylate ligands. The interlayer linkage is provided by hydrogen bonds from the carboxylic acid groups via the solvent water molecules [O...O = 2.565 (3) and 2.616 (3) Å] to the carboxylate groups in the next layer [O...O = 2.717 (3)–2.841 (3) Å], thereby extending the structures in the third dimension. 相似文献
135.
Olga N. Pozharitskaya Svetlana A. Ivanova Alexander N. Shikov Valery G. Makarov 《Chromatographia》2013,76(19-20):1353-1358
Chromatographic separation, analysis of in situ radical-scavenging activity, and quantitative analysis of green sea urchin shell pigments were carried out by online HPTLC-DAD and HPTLC-DPPH methods. Methanol:chloroform:acetic acid:water (11:50:5:2, v/v) was selected as the best mobile phase on silica gel plates for the separation of the pigments. Two pigment spots, S1 and S2, were observed on the TLC plates, while echinochrome A was not detected in the pigment extract of green sea urchin shells. Based on the estimated ID50 values, the antiradical activity was S2 (0.043 μg) > S1 (0.058 μg) > echinochrome A (0.134 μg). 相似文献
136.
Angelina Biitseva Ulrich Groth Olga Hordiyenko 《Journal of heterocyclic chemistry》2013,50(5):1140-1145
A reaction of phthalonitrile with thiosemicarbazide and α‐haloketones proceeded in one‐pot, giving rise to 3‐amino‐1H‐isoindol‐1‐one thiazol‐2‐ylhydrazones in high yields. 相似文献
137.
138.
Nina K. Gusarova Pavel A. Volkov Nina I. Ivanova Boris G. Sukhov Ludmila I. Larina Olga N. Kazheva Grigorii G. Alexandrov Oleg A. D’yachenko Boris A. Trofimov 《Tetrahedron letters》2013
The oxidative cross-coupling between 4-hydroxy-6-methyl-2-pyrone or 3-hydroxy-2-methyl-4-pyrone and secondary phosphine chalcogenides proceeds in CCl4/Et3N under mild conditions (20–52 °С, 0.75–10 h) through the hydroxyl group to give O-(6-methyl-2-oxo-2H-pyran-4-yl) diorganylphosphinochalcogenoates or O-(2-methyl-4-oxo-4H-pyran-3-yl) diorganylphosphinochalcogenoates, in high yields. 相似文献
139.
140.
Four implicit membrane models [IMM1, generalized Born (GB)‐surface area‐implicit membrane (GBSAIM), GB with a simple switching (GBSW), and heterogeneous dielectric GB (HDGB)] were tested for their ability to discriminate the native conformation of five membrane proteins from 450 decoys generated by the Rosetta‐Membrane program. The energy ranking of the native state and Z‐scores were used to assess the performance of the models. The effect of membrane thickness was examined and was found to be substantial. Quite satisfactory discrimination was achieved with the all‐atom IMM1 and GBSW models at 25.4 Å thickness and with the HDGB model at 28.5 Å thickness. The energy components by themselves were not discriminative. Both van der Waals and electrostatic interactions contributed to native state discrimination, to a different extent in each model. Computational efficiency of the models decreased in the order: extended‐atom IMM1 > all‐atom IMM1 > GBSAIM > GBSW > HDGB. These results encourage the further development and use of implicit membrane models for membrane protein structure prediction. © 2012 Wiley Periodicals, Inc. 相似文献