E. S. Starnovskaya, A. L. Muzyka, A. A. Yurtaeva, A. E. Kopotilova, D. S. Kopchuk, V. S. Gaviko, O. S. Taniya, E. V. Nosova, G. V. Zyryanov, V. L. Rusinov
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引用次数: 0
Abstract
The cyclocondensation of 2-aminobenzamide with 3,4-dimethoxypyridine-2-carbaldehyde affords a mixture of 2-(3,4-dimethoxypyridin-2-yl)-2,3-dihydroquinazolin-4(1H)-one and its open-chain tautomer. The dehydrogenation of these compounds with benzoquinones (DDQ, chloranil) as oxidants, giving 2-(pyridin-2-yl)quinazolin-4(3H)-ones, is accompanied by the demethylation of the methoxy group at the C(3) position of the 2-pyridyl moiety. When using 2-methoxy- or 2,3,4-trimethoxybenzaldehydes as deaza analogs of this aldehyde, the demethylation does not occur in the last step regardless of the nature of the oxidant.
期刊介绍：
Publishing nearly 500 original articles a year, by leading Scientists from Russia and throughout the world, Russian Chemical Bulletin is a prominent international journal. The coverage of the journal spans practically all areas of fundamental chemical research and is presented in five sections:
General and Inorganic Chemistry;
Physical Chemistry;
Organic Chemistry;
Organometallic Chemistry;
Chemistry of Natural Compounds and Bioorganic Chemistry.
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