Enantioselective Syntheses of Rigidiusculamides A and B: Revision of the Relative Stereochemistry of Rigidiusculamide A
作者:Gui-Yang Chen、Huang Huang、Jian-Liang Ye、Ai-E Wang、Hui-Ying Huang、Hong-Kui Zhang、Pei-Qiang Huang
DOI:10.1002/asia.201100809
日期:2012.3.5
achieved by two synthetic routes. The first one is convergent based on the common intermediate 11, obtained through a high yielding SmI2‐mediated Reformatsky‐type reaction. A highly diastereoselective one‐pot Dess–Martin periodinane‐mediated bis‐oxidation allowed the direct conversion of the diastereomeric mixture of 11 into rigidiusculamide B (8). Isolation of minor diastereomer 21, in combination with computational
的细胞毒性的天然产物的第一对映选择性合成rigidiusculamides A(ent- 21)和B(8)是由两个合成途径来实现的。第一个是基于通用中间体11收敛的,该中间体是通过高产量SmI 2介导的Reformatsky型反应获得的。高度非对映选择性的单锅Dess-Martin高碘烷介导的双氧化使11的非对映异构体混合物直接转化为刚性链霉菌素B(8)。较小的非对映异构体21的分离,结合计算工作,使我们提出了天然刚性链霉酰胺A的结构为21,由第二条路线综合而成。四个非对映体(7,7,图22A,和22B)和对映异构体(21 rigidiusculamide A(的)21)已经被合成。根据文献的先例和计算工作,有人提出了刚性链霉菌酰胺A和B的生物合成途径,以解释这两个同类物在C-5处的相反构型。