Synthesis of New Allocolchicinoids with Seven- and Eight-Membered B-Rings by Enyne Ring-Closing Metathesis
作者:François-Didier Boyer、Issam Hanna
DOI:10.1002/ejoc.200800595
日期:2008.10
functionality in the C-ring at the C10 or C11 positions, is reported. An asymmetric synthesis of (7S)-allocolchicine 5 is also described. The main features included the elaboration of a common intermediate, the AB bicyclic ring system, in which the construction of the seven-membered ring was achieved by an enyne ring-closingmetathesis (RCM) reaction. A subsequent Diels–Alder/aromatization sequence afforded the