Total Synthesis of (−)-Lepadiformine A Utilizing Hg(OTf)<sub>2</sub>-Catalyzed Cycloisomerization Reaction
作者:Keisuke Nishikawa、Seiho Kikuchi、Shinnosuke Ezaki、Tomoyuki Koyama、Haruka Nokubo、Takeshi Kodama、Yoshimitsu Tachi、Yoshiki Morimoto
DOI:10.1021/acs.orglett.5b02867
日期:2015.12.4
alkaloid (−)-lepadiformine A (1) possesses a unique structure characterized by the trans-1-azadecalin AB ring system fused with the AC spiro-cyclic ring. In this research, we found that a cycloisomerization reaction from amino ynone 2 to a 1-azaspiro[4.5]decane skeleton 3, corresponding to the AC ring system of 1, is promoted by Hg(OTf)2. Thus, we have accomplished the efficient total synthesis of (−)-lepadiformine
具有细胞毒性的海洋生物碱(-)-lepadiformine A(1)具有独特的结构,其特征是反式-1- azadecalin AB环系统与AC螺环稠合。在这项研究中,我们发现Hg(OTf)2促进了从氨基炔酮2到1- azaspiro [4.5]癸烷骨架3(对应于AC环系统1)的环异构化反应。因此,我们通过以新颖的Hg(OTf)2催化的环异构化为特征,完成了(-)-lepadiformine A的有效全合成,总产率为28%。