Progress toward a convergent approach for the enantioselective synthesis of the Veratrum alkaloid jervine is presented. The two requisite fragments were stereoselectively and efficiently fashioned from economical and readily available reagents. Key reactions include (a) a highly diastereoselective Ireland-Claisen rearrangement to establish the necessary cis-relationship between the amine and methyl
提出了对映选择性合成藜芦
生物碱 jervine 的聚合方法的进展。这两个必需的片段是由经济且容易获得的试剂立体选择性且有效地形成的。关键反应包括 (a) 高度非对映选择性的 Ireland-Claisen 重排,以在
四氢呋喃 E 环上的胺和甲基之间建立必要的顺式关系; (b) 非对映选择性
硒醚化反应,使 D/E oxaspiro[4.5]
癸烯能够组装成所需的构型; (c) 丰富的非手性二醇在生成关键四碳结构单元的过程中进行酶促去对称化,作为受保护的罗氏酯还原的实用替代方案。