Asymmetric Total Synthesis of (−)-Laulimalide: Exploiting the Asymmetric Glycolate Alkylation Reaction
作者:Michael T. Crimmins、Matthew G. Stanton、Shawn P. Allwein
DOI:10.1021/ja026269v
日期:2002.5.1
A concise total synthesis of the potent antitumor macrolide (-)-laulimalide is described. The observation that homoallylic (or latent homoallylic) C-O bonds are present at C5, C9, C15, C19, and C23 led to the strategic decision to rely heavily on the asymmetric glycolate alkylation to construct both the C1-C14 fragment 3 and the C15-C27 subunit 4. A diastereoselective addition of a C1-C14 allylstannane
描述了有效的抗肿瘤大环内酯 (-)-月桂内酯的简明全合成。C5、C9、C15、C19 和 C23 处存在同烯丙基(或潜在同烯烯丙基)CO 键的观察导致战略决策严重依赖不对称乙醇酸烷基化来构建 C1-C14 片段 3 和 C15- C27 亚基 4。C1-C14 烯丙基锡烷与 C15-C27 α,β-环氧醛的非对映选择性添加用于连接两个高级片段。羟基酸 2 的 Mitsunobu 大环内酯化避免了敏感的 2,3-Z-烯酸酯的异构化,这已在碱催化的大环内酯化中观察到。去除两个 TBS 保护基团以显示 C15 和 C20 羟基,而没有重排为异月桂内酯。