Total Synthesis of (-)-Sessilifoliamide C and (-)-8-epi-Stemoamide

A convergent route featuring [3,3]-sigmatropic rearrangements of a linchpin azepinopyrrolidine served to install two of the four contiguous stereocenters present in the tricyclic Stemona alkaloids sessilifollamide and stemoamide. In addition to the first total synthesis of (-)-sessilifoliamide C, a potential biosynthetic relationship between the sessilifoliamides and previously reported Stemona alkaloids is presented.