Novel heterocycles.<b>4</b>. Synthesis of the pyrido[2,3-<i>c</i>]-1,2-thiazine ring system
作者:Gary M. Coppola、Goetz E. Hardtmann
DOI:10.1002/jhet.5570160714
日期:1979.11
The reaction of 2-chloronicotinonitrile with N-methylmethanesulfonamide and subsequent treatment with base furnished the novel pyrido[2,3-c]-1,2-thiazine ring system 7. Spectrally, it was determined that the predominant tautomer in solution was the 4-amino form 7a. Acidic hydrolysis of 7 furnished the 4-oxo tautomer 8b, compound 8b was alkylated on oxygen with 1-bromopentane in the presence of sodium
2-氯烟腈与N-甲基甲磺酰胺的反应及随后的碱处理提供了新颖的吡啶并[2,3 - c ] -1,2-噻嗪环系统7。光谱确定溶液中主要的互变异构体是4-氨基形式7a。7的酸水解提供了4-氧代互变异构体8b,在氢化钠存在下用1-溴戊烷在氧上将化合物8b烷基化。的反应图8b与异氰酸酯发生在3位,以产生甲酰苯胺10。还讨论了这些化合物的光谱特性。