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71.
72.
73.
The title compound a novel cyclophane containing p-tropoquinone, was synthesized starting from 5-methoxytropolone and its physical properties were discussed comparing with those of 3,7-dimethyl-p-tropoquinone and p-benzoquinonophane. The reduced quinone character exhibited by was ascribed to the intramolecular CT interaction and the deformation of the quinone ring. 相似文献
74.
G. P. Moiseeva Sh. Z. Kasymov M. R. Yagudaev G. P. Sidyakin 《Chemistry of Natural Compounds》1980,16(3):254-256
It has been shown that it is possible to use the method of circular dichroism to determine the absolute configuration of the asymmetric center at C11 in the eudesmanolides. The orientations of the hydroxy group at C1 and of the methyl group at C4 in arabsin have been established.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 343–346, May–June, 1980. 相似文献
75.
Reaction of 1, 3-dimethylbenzimidazolone and its 5-methyl and 5-chloro derivatives with -valerolactone in presence of anhydrous aluminum chloride gives the corresponding 6-(1-methyl-3-carboxypropyl)-benzimidazolones. 相似文献
76.
Electroreduction of benzo-1,2,3-dithiazolium salts and their selenium analogs in nonaqueous solution
V. Sh. Tsveniashvili M. V. Malashkhiya V. N. Gaprindashvili B. Kh. Strelets M. M. Gel'mont Yu. I. Akulin 《Chemistry of Heterocyclic Compounds》1985,21(2):181-184
The electroreduction of benzo-1,2,3-dithiazolium cations and their selenium analogs in aprotic solvents takes place in two steps. The first step is a reversible, one-electron transfer leading to the formation of stable radicals detected by EPR. As a result of further electroreduction, the radicals obtained combine with six electrons to form the corresponding o-aminothio(seleno)phenols. Analysis of the reduction potentials of the compounds studied shows that the substitution of a selenium atom for a sulfur in these cations, especially in the 2 position of the heterocycle, facilitates their electrochemical reduction. The electrochemical activity and the kinetics of nulceophilic substitution in the cations studied are compared.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 219–222, February, 1985. 相似文献
77.
A. Ya. Fridman A. Yu. Tsivadze N. P. Sokolova N. S. Polyakov R. Sh. Vartapetyan A. M. Voloshchuk G. A. Petukhova I. I. Bardyshev A. M. Gorbunov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2007,81(4):593-597
Polyvinylchloride (PVC) samples with a fairly developed surface were prepared by the spontaneous removal of the solvent (benzyl alcohol) from a polymer gel. The surface of the product was modified to obtain ethanolocyclame and sodium acetocyclame nanofilms. The structure and composition of the nanofilms were studied by IR Fourier spectroscopy. The adsorption of nitrogen vapor at ?196°C and benzene and water at 20°C on the nanofilms was investigated. Surface modification was shown to increase the stability of PVC in water and benzene and the specific surface area and volume of nanopores. The conclusion was drawn that nanofilm ligand groups could stoichiometrically interact with water and benzene molecules on PVC with a modified surface. 相似文献
78.
V. S. Abdukakharov U. A. Turakhanov M. M. Kasymzhanova A. S. Korneev Sh. I. Salikhov A. A. Abduvakhabov 《Chemistry of Natural Compounds》1994,30(1):130-132
A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax 627071. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 137–139, January–February, 1994. 相似文献
79.
G. A. Gainanova E. P. Zhil’tsova L. A. Kudryavtseva S. V. Kharlamov Sh. K. Latypov A. P. Timosheva A. I. Konovalov 《Russian Chemical Bulletin》2006,55(8):1411-1418
Micelle formation in a cetyltrimethylammonium bromide-poly(ethylene glycol)-600 monolaurate-chloroform system in the absence
and presence of hydroxybenzylated polyethylenimines (PEI) was studied by dielcometric titration, NMR self-diffusion, light
scattering, and kinetic methods. A catalytic effect of mixed micelles on the reaction of 4-nitrophenylbis(chloromethyl)phosphinate
with PEI was shown. The catalytic effect depends on the degree of substitution of PEI and composition of a surfactant mixture.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1359–1365, August, 2006. 相似文献
80.
Contrary to the precedents, 1,3-anti stereoselection was found in the intramolecular Michael addition of ethyl ,5-carbamoyloxy-4-trialkylsilyloxy-2-hexenoate to culminate in a synthesis of N-benzoyl-,-daunosomine. The antiperiplanar effect due to the group at 4-position was revealed to play a major role in the stereoselection in this type of reactions. N-benzoyl-,-3-epidaunosamine was also synthesized by 1,2-syn asymmetric induction. 相似文献