Abstract: The synthesis of 8-epi-dendrobine (lb) is described in which stereochemistry is established via intramolecular Diels-Alder cyclization of triene ester 2 to give the unsaturated nitrile ester 3. Intermediate 3 is elaborated to lb via two independent synthetic routes, one proceeding via. keto lactone 12d and the other via amino ester 14. Inversion of stereochemistry at C-8 is believed to occur as a consequence of diene isomerization ...
