Вид документа : Статья из журнала Шифр издания : 54/Q 32 Автор(ы) : Chupakhin O. N., Charushin V. N., Chernyshev A. I., Esipov S. E. Заглавие : Quaternization of pyrido[2,3-b]pyrazines: 1H and 13C NMR Study [Электронный ресурс] Место публикации : Magnetic Resonance in Chemistry. - 1985. - Vol. 23, № 6. - С. 437-441 Систем. требования: http://onlinelibrary.wiley.com/doi/10.1002/mrc.1260230607 Примечания : Bibliogr. : p. 441 (20 ref.). - 26.10.15 ББК : 54 Предметные рубрики: ХИМИЧЕСКИЕ НАУКИ Ключевые слова (''Своб.индексиров.''): n-methylpyrido[2,3-b]pyrazinium salts--pyrido[2,3-b]pyrazines Аннотация: The structure of N-methylpyrido[2,3-b]pyrazinium salts has been examined by 1H and 13C NMR. 6-Dimethylamino- and 6-morpholino-pyrido[2,3-b]pyrazines were shown to undergo quaternization by methyl iodide at N-4 of the pyrazine ring, whereas the pyridine ring N-5 was the N-alkylation site in the reaction of unsubstituted pyrido[2,3-b]pyrazine with methyl iodide under the same conditions. The effects of quaternization on the 1H and 13C chemical shifts and the nJ(CH) values are discussed. Доп.точки доступа: Chupakhin, O. N.; Charushin, V. N.; Chernyshev, A. I.; Esipov, S. E.