Scalable Total Synthesis of (+)- and (−)-Codonopiloneolignanin A via Ti(IV)/NHC Cooperative Control Highly Enantioselective Dimerization of Multisubstituted Cinnamaldehyde
作者:Xiangxin Li、Huaya Yong、Xiaohong Fan、Yajuan Zheng、Zhen Wang、Zhixiang Xie
DOI:10.1021/acs.orglett.1c02408
日期:2021.8.20
asymmetric total synthesis of (+)- and (−)-codonopiloneolignanin A has been achieved from multisubstituted cinnamaldehyde in four steps with 37% overall yield. The synthetically challenging tricyclic [5, 3, 0, 03,8] decane skeleton was efficiently constructed via a highly enantioselective dimerization of multisubstituted cinnamaldehyde, followed by a sequence of cascade reactions including Prins cyclization
(+)-和(-)-codonopiloneolignanin A 的第一个克级不对称全合成已从多取代肉桂醛中分四步实现,总产率为 37%。具有挑战性的三环 [5, 3, 0, 0 3,8 ] 癸烷骨架是通过多取代肉桂醛的高度对映选择性二聚作用有效构建的,然后是一系列级联反应,包括 Prins 环化、阳离子介导的环化和脱保护。此外,研究了 NHC 催化/Ti(IV) 介导的协同控制多取代肉桂醛二聚的范围。重要的是,codonopiloneolignanin A 及其对映异构体的生物活性在自然界中特别稀缺,经测试并显示出良好的抗癌活性。