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T. Yu. Samgina P. A. Sharbatyan L. S. Shishkanova N. A. Andronova A. I. Pavlyuchenko V. V. Titov 《Chemistry of Heterocyclic Compounds》1987,23(11):1207-1211
The basic principles of the mass-spectral fragmentation of arylalkylpyridines that contain substituents in various positions were established. The principle ions that can be used in Chromatographic mass-fragmentographic analysis in the study of liquid-crystal compositions were determined for each specific case.Communication 1 of the series Mass spectra of liquid crystalsTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1509–1513, November, 1987. 相似文献
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V. P. Lezina V. F. Bystrov B. E. Zaitsev N. A. Andronova L. D. Smirnov K. M. Dyumaev 《Theoretical and Experimental Chemistry》1972,5(2):159-163
To explain the character of the intramolecular hydrogen bond in substituted 3-hydroxypyridines, the chemical shifts in the NMR spectra of the hydroxyl group and the IR spectra were studied. It was established that the stability of the intramolecular hydrogen bond of the O-HNR2 type in substituted 3-hydroxypyridines increases when compared with the corresponding phenols, while an opposite pattern is observed for bonds of the O-H02 N type. An approximate evaluation of the energy of the intramolecular hydrogen bond in substituted 3-hydroxypyridines was achieved. When reacting with bases of the same strength, 3-hydroxypyridine forms more stable complexes than phenol. 相似文献
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Yu. N. Porshnev V. A. Churkina N. A. Andronova V. V. Titov 《Chemistry of Heterocyclic Compounds》1977,13(7):728-731
2-Phenyl- and 1,2-diphenylbenzo[b]cyclopenta[e]pyrans were subjected to formylation, nitration, and phenylsufonylation. It was shown by PMR spectroscopy that 2-phenylbenzo[b]cyclopenta[e]pyran undergoes substitution exclusively in the 1 position. The effect of the spatial orientation and the degree of electron-acceptor character of the introduced substituents on the chemical shift of the 9-H proton was studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 902–905, July, 1977. 相似文献
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Vozdvizhenskaya Olga А. Andronova Valeriya L. Galegov Georgii А. Levit Galina L. Krasnov Victor P. Charushin Valery N. 《Chemistry of Heterocyclic Compounds》2021,57(4):490-497
Chemistry of Heterocyclic Compounds - A method for the synthesis of novel purine conjugates with 7,8-difluoro-3-methyl-3,4-dihydro-2H-1,4-benzoxazine containing fragments of ω-amino acids with... 相似文献
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A. M. Andrievskii O. V. Chelysheva A. N. Poplavskii V. V. Nikonov L. A. Chetkina V. K. Bel'skii V. E. Zavodnik A. A. Perov N. A. Andronova K. M. Dyumaev 《Chemistry of Heterocyclic Compounds》1990,26(6):658-663
Treatment of 2-bromo-6(5H)-phenanthridone with nitrating mixture or fuming nitric acid results in nitration, debromination, and bromination in the 10-position. The brominating agent is apparently Br+, formed in the reaction mixture following replacement of the bromine in the 2-position by a nitro-group. Monocrystals of 2-bromo-1,4,8-trinitro-6(5H)-phenanthridinone and 10-bromo-2,4,8-trinitro-6(5H)-phenanthridinone have been subjected to x-ray diffraction examination. PMR has been used for structural identification.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 789–795, June, 1990.We thank A. N. Sobolev for assistance in calculating the structure of (III). 相似文献
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