1-(2-Cyanomethylsulfanyl-5-ethoxycarbonyl-4-methyl-thiophen-3-yl)-3,5-dimethyl-pyridinium; bromide 在
1,8-二氮杂双环[5.4.0]十一碳-7-烯 作用下,
以
氯仿 为溶剂,
反应 0.25h,
生成 (5R,5aR)-5-Cyano-1,6,8-trimethyl-5,5a-dihydro-pyrido[1,2-d]thieno[2,3-b][1,4]thiazine-2-carboxylic acid ethyl ester 、 (5S,5aR)-5-Cyano-1,6,8-trimethyl-5,5a-dihydro-pyrido[1,2-d]thieno[2,3-b][1,4]thiazine-2-carboxylic acid ethyl ester