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61.
A. S. Romakhin F. M. Palyutin Yu. A. Ignat'ev E. V. Nikitin Yu. M. Kargin I. A. Litvinov V. A. Naumov 《Russian Chemical Bulletin》1990,39(3):585-589
The electrochemical oxidation of hexaethyl triamidophosphite in the absence of nucleophiles specially introduced into the electrolyte was studied by anodic voltamperometry and preparative electrolysis. The reversible one-electron oxidation of the triamidophosphite molecule gives an unstable radical-cation, which reacts with a molecule of the starting compound to give a dimeric radical-cation, whose subsequent oxidation leads to dodecaethylhexaamidobisphosphonium diperchlorate. This product is the first example of an acyclic, doubly charged bisphosphonium cation with a
. The crystal structure of this compound was obtained by x-ray diffraction structure analysis.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 664–669, March, 1990. 相似文献
62.
N-Methylmorpholinium 4-aryl-5-cyano-2-oxo-2-oxo-1,2,3,4-tetrahydropyridine-6-thiolates were obtained by the condensation of
aromatic aldehydes, cyanothioacetamide, and Meldrum's acid in the presence ofN-methylmorpholine. They were then used in the syntheses of substituted 6-alkylthio-3,4-dihydropyridin-2(1H)-ones and 4,5-dihydrothieno[2,3-b]pyridin-6(7H)-ones.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1852–1856, October, 1997. 相似文献
63.
V. A. Al'fonsov I. A. Litvinov O. N. Kataeva D. A. Pudovik S. A. Katsyuba 《Russian Chemical Bulletin》1995,44(10):1897-1899
X-Ray study of (diethyldithiocarbomoyl)diphenylthiophosphinate was carried out. AZ-conformation of the diethyldithiocarbomoyl ligand, which results in a short nonvalent intramolecular P...S contact (3.315 Å), is realized in the molecule. Steric hindrances in the molecule increase the P-S-C bond angle to 106.39°.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1978–1980, October, 1995.The work was financially supported by the International Science Foundation (Gram RH1 000). 相似文献
64.
V. G. Kharchenko S. N. Chalaya O. V. Litvinov 《Chemistry of Heterocyclic Compounds》1985,21(3):291-293
Under the influence of ammonia or ammonium acetate, -'-dichloro-substituted 1,5-diketones undergo heterocyclization to give -chloropyridines or 2-benzoylpyrrole derivatives. The structure of the final product depends on the reagent and the character of the substituent in the 3 position of the starting dichloro diketones.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 352–354, March, 1985. 相似文献
65.
B. A. Arbuzov Z. G. Isaeva M. G. Belyaeva V. V. Ratner O. N. Kataeva I. A. Litvinov V. A. Naumov 《Russian Chemical Bulletin》1992,41(1):117-119
Oxidation of 2-carene by lead tetraacetate in acetic acid afforded p-menth-1(10),2-dien-7-ol, 2-acetyl-6,6-dimethylbicyclo[3.1.0]hexane, p-menth-2-ene-1,7-diol, p-menth-1-ene-3,7-diol, and 2-(m-tolyl)propanol-2.Deceased.A. M. Butlerov Scientific Research Chemical Institute, V. I. Ul'yanov-Lenin Kazan' State University, 420008 Kazan. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 147–150, January, 1992. 相似文献
66.
Conclusions An x-ray diffraction structural analysis showed that the P-diastereomer of 1,2;3,4;5,6-tris-O-(diethylamidothionephosphate)galactite (C18H38N3O6P3S18) with melting point 178.5-179C has terminal dioxaphospholane rings in a cis arrangement. One of these rings has planar conformation, while the other has twist conformation. These rings also differ in the configuration of the phosphorus atom. The central ring has twist conformation.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1408–1410, June, 1988. 相似文献
67.
The condensation of acetaldehyde with a twofold excess of cyanothioacetamide andN-methylmorpholine givesN-methylmorpholinium 6-amino-3,5-dicyano-4-methylpyridine-2-thiolate. This compound is also formed by recyclization of 2,6-diamino-3,5-dicyano-4-methyl-4H-thiopyran. From this pyridinethiolate, several substituted 2-alkylthiopyridines and 3,6-diamino-5-cyano-4-methyl-2-methoxycarbonylthieno[2,3-b]pyridine were obtained. 相似文献
68.
Bytchenkoff D Pelupessy P Bodenhausen G 《Journal of the American Chemical Society》2005,127(14):5180-5185
A new method has been developed to obtain dynamic and structural information about peptide planes in proteins by a combination of measurements of weak short-range cross-correlation rates R(H(N)N/NC') that are due to concerted fluctuations of the H(N)-N and N-C' dipole-dipole interactions and stronger long-range cross-correlation rates R(C'H(N)/H(N)N) and R(NH(N)/H(N)C(alpha)). The rates were interpreted using the axially symmetric Gaussian axial fluctuation model (GAF). The oscillation amplitudes as well as the positions of H(N) atoms with respect to peptide planes in ubiquitin were determined. Most N-H(N) bonds were found not to lie exactly along the bisector of the N-C' and N-C(alpha) bonds but to be slightly tilted toward the carbon-terminal side of the peptide. 相似文献
69.
I. A. Litvinov O. N. Kataeva V. E. Kataev O. Yu. Butenko 《Russian Chemical Bulletin》1991,40(8):1607-1609
It was established by x-ray crystallographic analysis that the molecular o-nitrobenzyltriethylammonium cation has an orthogonal orientation of the benzene ring and the vicinal C-N+ bond (=93.8°). The nitro group deviates from the plane of the aromatic ring by an angle of 26.9°. One of the ethyl groups at the quaternary nitrogen atom is in an ap-conformation (=176.2°); the other two are in sc-conformations, characterized by torsional angles 65.1 and 69.4°.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1816–1818, August, 1991. 相似文献
70.
V. A. Artemov V. L. Ivanov A. V. Koshkarov A. M. Shestopalov V. P. Litvinov 《Chemistry of Heterocyclic Compounds》1998,34(1):96-101
Pyrido[3,2:4,5]thieno[2,3-c]cinnolines, new heterocyclic compounds, were obtained in three steps: 1) alkylation of 3-cyanopyridine-2(1H)-thiones by o-nitrobenzyl bromide to give 2-(o-nitrobenzyl)thio-3-cyanopyridines, 2) closure of the thiophene ring in these intermediates to give 3-amino-2-(o-nitrophenyl)thieno[2,3-b]pyridines, and 3) closure of the pyridazine ring by condensation of the amino and nitro groups in triethyl phosphite, leading to the final heterocyclic system.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 104–109, January, 1998. 相似文献