作者:Barry B. Snider、Jeremy R. Duvall
DOI:10.1021/ol0518784
日期:2005.9.1
[reaction: see text] Addition of the enolate of tert-butyl acetate to cyanamide methyl ester 17 followed by treatment with LHMDS afforded vinylogous urea 19 in 27% yield. Vinylogous urea 19 was also obtained from 37 and tert-butyl cyanoacetate in 50% yield. Acylation of 19 with acid chloride 31d, followed by hydrolysis of the tert-butyl ester and decarboxylation with 9:1 CH2Cl2/TFA and very mild basic
[反应:见正文]将乙酸叔丁酯的烯醇盐添加到氰胺甲酯17中,然后用LHMDS处理,得到乙烯基脲19,收率为27%。从37和氰基乙酸叔丁酯也获得了乙烯基脲19,收率为50%。19用酰氯31d酰化,然后叔丁基酯水解并用9:1 CH2Cl2 / TFA脱羧,甲氧基乙酸酯进行非常温和的碱性水解,得到4啶A1 / A2(3),产率为45%。第一次合成证实了我们对Jannamidines A1 / A2结构的重新分配。