Total synthesis of (−)-(2R,9S)- and (+)-(2S,9S)-stereoisomers of laingolide B has been accomplished by using sequential ring-closing metathesis (RCM) and alkene isomerization to construct the macrocyclic trans-N-methyl enamide moiety. The Myers alkylation was used to secure the C2 stereochemistry of the two RCM precursors from a common (9S)-C3–C9 alkyl iodide. The absolute configuration of laingolide B has been assigned as (2S,9R) by comparison of the optical rotation data.

中文翻译：

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Laingolide B立体异构体的全合成和绝对构型分配

Laingolide B的（-）-（2 R，9 S）-和（+）-（2 S，9 S）-立体异构体的全合成已通过使用顺序闭环复分解（RCM）和烯烃异构化来构建大环反式- ñ -甲基烯酰胺基团。Myers烷基化用于确保两种RCM前体的C2立体化学来自共同的（9 S）-C3-C9烷基碘。通过旋光度数据的比较，Laingolide B的绝对构型已指定为（2 S，9 R）。