derived tetrolate 7 yields the tricyclic lactone 8 (48–56%) with no significant loss of ee (less than 1%), thus demonstrating the feasibility of a total synthesis of forskolin in enantiomerically pure form according to our route. The present synthesis of the optically active lactone 8 (ee=98%) is the shortest and the most efficient.
对Corey
CBS方法的一种改进,用于不对称还原二烯酮3 A,得到的二烯醇4 A的ee = 98%(收率92%)。衍生的四醇盐7的分子内Diels-Alder反应产生
三环内酯8(48-56%),没有明显的ee损失(小于1%),从而证明了根据对映体纯形式完全合成
毛喉素的可行性。到我们的路线。光学活性内酯8(ee = 98%)的当前合成是最短和最有效的。