Synthesis of (−)-Nakamurol A and Assignment of Absolute Configuration of Diterpenoid (+)-Nakamurol A
作者:Sandra Díaz、Javier Cuesta、Asensio González、Josep Bonjoch
DOI:10.1021/jo034838r
日期:2003.9.1
The total synthesis of the enantiomer of the marine sponge diterpenoid nakamurol A and determination of the absolute configuration of this natural product are reported. This first synthetic entry to thelepogane-type diterpenoids involves the use of the bicyclic enone (-)-3, which after a tandem difunctionalization process and elongation of the side chain leads to the formation of the ketone (-)-13
报道了海洋海绵二萜类纳卡莫洛尔A的对映异构体的总合成以及该天然产物的绝对构型的确定。脂环烷型二萜类化合物的第一个合成入口涉及双环烯酮(-)-3的使用,该双环烯酮在串联双官能化过程和侧链延长后导致形成酮(-)-13。从(-)-13,报道了两种对中卡那洛尔A(1)的方法:通过与乙烯基溴化镁反应的直接但非选择性的途径,以及通过伯烯丙醇20的较长但立体控制的途径,该途径被提交给进行无尖锐的环氧化反应,然后进行碲促进的还原性环氧开环级联反应。