【作者】 厍学功； 许世炎； 谢新刚；

【Author】 Xuegong She;Shiyan Xu;Xingang Xie;State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University;

【机构】 兰州大学化学化工学院,功能有机分子化学国家重点实验室；

【摘要】 我们利用手型环氧引发的串联的碳正离子多烯环化反应,完成了具有结构特异性和较好生理活性的降三萜类天然产物(-)-Walsucochin B的首次对映选择性全合成。在一步构筑了天然产物的核心骨架和所有的手性中心后,采用一个位置选择性的自由基卤代反应和Seyferth-Gilbert增碳反应来引入所需炔基结构单元。通过对映选择性全合成,我们进一步确认了天然Walsucochin B的绝对构型。更多还原

【Abstract】 The first enantioselective total synthesis of the structurally unique nortriterpenoid(-)-walsucochin B has been accomplished through the cationic polyolefin cyclization initiated by chiral epoxide. The core framework and the stereocenters in the natural product were all constructed in this step. A site-selective, late-stage free-radical halogenation, and Seyferth-Gilbert homologation was adopted to install the acetylene moiety to synthesize the the phenylacetylene. The absolute configuration of walsucochin B was confirmed through enantioselective total synthesis.更多还原