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991.
A. M. Shestopalov Yu. A. Sharanin I. A. Aitov V. N. Nesterov Yu. T. Struchkov V. P. Litvinov 《Chemistry of Heterocyclic Compounds》1991,27(8):872-878
Highly regioselective reactions of pyridinium ylides with tetracyanoethylene occur via an AdN-E mechanism to form Z-isomers of 3-aroyl-3-(1-pyridinio)-1,1,2-tricyano-2-propenides-1, corresponding in structure to 1,4-ylides with maximum charge separation. If the unsaturated nitrite starting material contains a nucleofugal group 1,2-elimination predominates over 1,3-elimination.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1087–1094, August, 1991. 相似文献
992.
A convenient preparative method was developed to obtain substituted 2-allylthio-5- methyl-3-thiophenecarbaldoximes, which are starting compounds in the synthesis of fused heterocycles containing the thiophene ring, by the successive action of sodium in liquid ammonia and substituted -halopropenes on 2-methylthio-5-methyl-3-thiophenecarbaldoxime.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, PP. 247–251, January, 1991. 相似文献
993.
A new method for obtaining pyrrolobenzothiazole derivatives, which can be used for the specific synthesis of polymethine dyes with predesignated properties, was developed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 549–553, April, 1991. 相似文献
994.
G. V. Gridunova V. E. Shklover Yu. T. Struchkov R. A. Alimova M. V. Gorelik 《Chemistry of Heterocyclic Compounds》1988,24(4):398-403
The molecular and crystalline structure of 1-(2,4,6-trimethylphenyl)-6H-anthra-[9,1-bc]pyrrol-6-one was determined by the x-ray structural method. There is a larger uniformity of the bonds in the benzene ring of the isoindole fragment than in the N-substituted isoindoles; this derives from the electronic influence of the keto group. The structure of the whole molecule does not have marked 1,10-anthraquinoid character.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 485–490, April, 1988. 相似文献
995.
E. D. Skakovskii S. V. Rykov L. Yu. Tychinskaya Ya. N. Malkin 《Russian Chemical Bulletin》1987,36(8):1753-1755
Conclusions Negative polarization of the protons of aniline and other compounds is observed upon the photoexcitation of aniline solutions. This effect is a consequence of optical nuclear polarization in short-lived donor-acceptor complexes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1890–1892, August, 1987. 相似文献
996.
Yu. A. Zhdanov é. A. Zvezdina S. M. Statsenko A. N. Maksimova 《Chemistry of Heterocyclic Compounds》1987,23(2):149-154
The direct interaction of 2,6-diphenylpyrylium perchlorate with pyrazoles and pyrazolones led to the synthesis of 4-azolylpyrylium salts, which readily cleave a molecule of perchloric acid in the case of the N-unsubstituted pyrazolones, being converted to pyranylidene derivatives.For Communication 15, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 182–187, February, 1987. 相似文献
997.
998.
Khodzhaev B. U. Primukhamedov I. M. Yunusov S. Yu. 《Chemistry of Natural Compounds》1986,21(6):743-746
The amounts and compositions of the essential oils in the leaves and fruit of Meyer's lemon in the various vegetation periods have been studied. It has been established that as the fruit ripens the amount of essential oils and of monoterpene hydrocarbons in its peel and in the leaves increases.Institute of Plant Biochemistry, Academy of Sciences of the Georgian SSR. Sukhumi Zonal Experimental Station of Essential-Oil Crops. Sukhumi Experimental Station of Subtropical Crops, All-Union Institute of Plant Growing. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 784–787, November–December, 1985. 相似文献
999.
1000.