Divergent Total Synthesis of the Lycopodium Alkaloids Huperzine A, Huperzine B, and Huperzine U
作者:Rui Ding、Jian-Guo Fu、Guang-Qiang Xu、Bing-Feng Sun、Guo-Qiang Lin
DOI:10.1021/jo402419h
日期:2014.1.3
Buchwald–Hartwig coupling and Heck cyclization reactions and an Ir-catalyzed olefin isomerization reaction. This work has established the absolute configurations of huperzine B and huperzine U and revealed that natural huperzine A, huperzine B, and huperzine U possess the same set of absolute stereochemistries, thus providing support for the potential role of huperzine B and huperzine U in the biosynthesis of huperzine
石杉碱甲,石杉碱B和石杉碱U是从中草药石杉石杉(=石柏石藻)中分离出来的同类物,含量极少。石杉碱A的最有效全合成,石杉碱B的第一个不对称全合成和石杉碱U的第一个全合成已分别有效地实现,总收率分别为10%,10%和9%。从(R出发13步)-pulegone。特色步骤包括钯催化的Buchwald-Hartwig偶联和Heck环化反应以及Ir催化的烯烃异构化反应。这项工作建立了石杉碱B和石杉碱U的绝对构型,并揭示了天然石杉碱A,石杉碱B和石杉碱U具有相同的一组绝对立体化学,从而为石杉碱B和石杉碱U在生物合成中的潜在作用提供了支持。石杉碱甲