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21.
V. A. Makarov A. L. Sedov O. S. Anisimova V. G. Granik 《Chemistry of Heterocyclic Compounds》1996,32(6):699-707
Highly polarized enediamines of the a, -diamino--cyano--nitroethylene type have been obtained by the hydrolysis of 4-chloro-5-nitropyrimidines. Several chemical conversions of the enamines obtained have been studied, particularly leading to derivatives of 2-(cyanonitromethylene)imidazoline and -hexahydropyrimidine, and also to derivatives of N, N-bisvinylpiperazine and 7 methylene-1, 4-diazabicyclo(2.2. 1 ]heptane.Center for Drug Chemistry, All-Russian Chemical and Pharmaceutical Research Institute, Moscow 119815. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 811–820, June, 1996. Original article submitted February 6, 1996.For Part 1, see [1]. 相似文献
22.
B. L. Tumanskii A. A. Kadyrov O. A. Popova L. T. Lantseva N. N. Bubnov S. P. Solodovnikov K. N. Makarov 《Russian Chemical Bulletin》1991,40(5):903-907
The EPR method was used to study the structure of spin adducts of silyl and phosphonyl radicals with higher internal perfluoroalkenes. The capacity for spin adducts to split off hydrogen atoms is determined by the degree of steric screening of the free radical center. The preparative photochemical reaction of hydrosilanes and dialkyl phosphites with perfluoro-4-methylpent-2-ene leads to regiospecific hydrosilylation and hydrophosphorylation products with yields up to 80%.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1018–1023, May, 1991. 相似文献
23.
Aleinikov N. N. Vasil'ev G. K. Kashtanov S. A. Makarov E. F. Chernyshev Yu. A. 《Kinetics and Catalysis》2001,42(2):233-237
The dependence of the rate of a photochemical reaction of XeO4with H2on the concentrations of H2and the diluent gases He and CO2is studied at room temperature. The results are compared with the data for the dark reaction. A mechanism with the elementary energetic branched-chain reaction OH
(v) + XeO4OH
+ O
+ XeO3is proposed to explain the results of the study. 相似文献
24.
É. I. Fedin P. V. Petrovskii L. A. Fedorov Yu. V. Makarov N. E. Kolobova K. N. Anisimov 《Russian Chemical Bulletin》1973,22(9):2093-2095
Conclusions The electron density on the-cyclopentadienyl ligand in cyclopentadienylmanganese tricarbonyl derivatives is higher than in the corresponding cyclopentadienylrhenium tricarbonyl derivatives.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2142–2143, September, 1973. 相似文献
25.
Vadim?B.?Fetisov Alexander?N.?Ermakov Galina?M.?Belysheva Andrey?V.?Fetisov Valentin?M.?Kamyshov Khiena?Z.?BraininaEmail author 《Journal of Solid State Electrochemistry》2004,8(8):565-571
The present paper deals with the electrochemical behavior of magnetite microcrystals in an acid medium. A voltammetric method employing a carbon-paste electroactive electrode (CPEE) with an organic binder was used. It was found that the cathodic voltammograms, which were recorded at different scan rates, formed a set bounded in the space of i–E parameters by a generalizing voltammetric curve corresponding to the effective potential scan rate eff. In other words, all curves are situated under one enveloping curve, just as the smaller dolls sit in the largest doll of a Russian doll. Reverse currents (a cathodic current in the anodic direction of the potential scan) were observed on the cyclic voltammogram. Forward and reverse currents obey the same laws and have one and the same generalizing curve, which could be taken as the magnetite characteristic. 相似文献
26.
Kudrik EV Theodoridis A van Eldik R Makarov SV 《Dalton transactions (Cambridge, England : 2003)》2005,(6):1117-1122
Catalytic oxidation of N,N'-dimethylthiourea and thiourea by dioxygen in water using a new cobalt(II) complex of octasulfophenyltetrapyrazinoporphyrazine was performed under mild conditions. The reaction is shown to include the formation of an intermediate anionic five-coordinate complex followed by an unusual two-electron oxidation to produce the corresponding urea and elemental sulfur (S8). Kinetic and thermodynamic parameters for the different reaction steps of the process were determined. Drastic differences in catalytic activity of cobalt and iron octasulfophenyltetrapyrazinoporphyrazines were observed. 相似文献
27.
Ostroushko A. A. Shubert E. Makarov A. M. Minyaev V. I. Udilov A. E. Elokhina L. V. Aksenova V. I. 《Russian Journal of Applied Chemistry》2003,76(8):1253-1259
The catalytic activity of composites constituted by a porous metallic or ceramic support, intermediate layers of oxide nature, and perovskite coatings, including those doped with silver, was studied in reactions of deep oxidation of CO and organic compounds of various classes. The relationship between the catalytic activity of a composite and its composition and nature of substances being oxidized was analyzed. 相似文献
28.
N. D. Kagramanov A. A. Kutin E. I. Mysov K. N. Makarov L. L. Gervits 《Russian Chemical Bulletin》1990,39(5):925-930
The primary and final products arising from the pyrolysis of perfluoro-2,4-dimethyl-3-ethylpentane, perfluoro-3-isopropyl-4-methyl-2-pentene, perfluoro-2-methyl-3-isopropyl-2-pentene, perfluoro-2,4-dimethyl-3-heptene, and perfluoro-4-methyl-2-pentene have been studied using low-energy mass spectrometry and chromatography-mass spectrometry. Thermal decomposition of hexafluoropropene oligomers, containing perfluoroisopropyl groups attached to a double bond, occurs via loss of a radical pair to form perfluorodienes, as well as via abstraction of a hexafluoropropene molecule from the iso-C3F7 group. A correlation between the principal fragmentation pathway observed under electron impact and the primary process in the main thermolysis pathway was detected only in the case of perfluoro-4-methyl-2-pentene and perfluoro-2,4-dimethyl-3-heptene, which are capable of cleavage of.CF3 and.C2F5 radicals, respectively, to give a single possible allyl radical structure.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1037–1041, May, 1990. 相似文献
29.
Dudkin VY Orlova M Geng X Mandal M Olson WC Danishefsky SJ 《Journal of the American Chemical Society》2004,126(31):9560-9562
Synthetic gp120331-335 glycopeptide fragments carrying hybrid and high-mannose type N-linked glycans were evaluated for binding to broadly neutralizing antibody 2G12 using surface plasmon resonance technology. None of the hybrid-type constructs demonstrated binding to 2G12. In the high-mannose series, the "Cys dimer" construct, presenting two undecasaccharide glycans, showed significantly higher binding than the Cys-protected monomer. The binding of the dimeric structure was further investigated in competition with recombinant gp120. The data suggest that gp120 and its designed synthetic epitope construct bind to the same site on 2G12. 相似文献
30.
Previously unknown polyfluorocyclohexenyl, and acyclic perfluoroalkenyliodine tetrafluorides were prepared in high yields. Perfluorocyclohex-1-enyliodine tetrafluoride was obtained from pentafluoroiodobenzene using XeF2-NbF5 in aHF. The reaction of C6F5I with the weaker fluorooxidant XeF2-BF3 in 1,1,1,3,3-pentafluorobutane (PFB) yielded C6F5IF2, perfluorocyclohexa-1,4-dienyliodine difluoride, C6F5IF4, perfluorocyclohexa-1,4, and 1,3-dienyliodine tetrafluoride as intermediate products on parallel reaction routes. Both perfluoroalkenyl iodides, cis- and trans-(CF3)2CFCFCFI, reacted with XeF2-BF3 in PFB to give the corresponding perfluoroalkenyliodine tetrafluorides, cis- and trans-(CF3)2CFCFCFIF4. Even perfluoroalkyl iodides can be fluorinated by this reagent as was demonstrated by the preparation of C6F13IF4 from C6F13I. Generally, the CFCIFn fragment (n = 0, 2, or 4) in cyclic or acyclic perfluoroalkenyliodine compounds RFIFn did not undergo a transformation to the corresponding perfluoroalkyliodine compound. Furthermore, no perfluoroorganoiodine hexafluorides were detected in reactions with the fluorooxidant XeF2-aHF or BF3 or NbF5. 相似文献