作者:Lijian Chen、Ellen Dovalsantos、Jian Yu、(Kuen-Shan)Steven Lee,、Stacy O'Neill-Slawecki、Mark Mitchell、Sylvie Sakata、Ben Borer
DOI:10.1021/op0600916
日期:2006.7.1
(Pyridonyl-1)propargyl malonate 7 was prepared through two consecutive alkylations of pyridone 2 with ethyl bromomalonate and propargyl bromide in one pot in nearly quantitative yields. Malonate 7 was hydrolyzed to give racemic acid (±)-1, which was then resolved with (−)-norephedrine to give (S)-1. The recovered acid, which was enriched with undesired (R)-1, was activated with CDI, and a complete
(吡啶基-1)丙炔基丙二酸酯7是通过将吡啶酮2与溴代丙二酸乙酯和炔丙基溴在两个锅中连续两次烷基化而制备的,其产率接近定量。丙二酸酯7水解得到外消旋酸(±)-1,然后将其与(-)-去氧麻黄碱拆分得到(S)-1。用CDI活化富含不希望的(R)-1的回收酸,并在室温下在三乙胺存在下实现完全消旋。丙二酸酯7也用溴化锂处理,并进行选择性单脱羧,得到(吡啶基-1)炔丙基乙酸酯图6是酶促拆分底物,直接产率为87%。