Evolution of a strategy for the synthesis of structurally complex batzelladine alkaloids: Enantioselective total synthesis of the proposed structure of batzelladine F and structural revision

A synthesis is presented of 2a,8a-syn tricyclic guanidines corresponding to the originally proposed relative configuration of these units of batzelladine F. A description is provided on the preparation of analogous 2a,8a-syn tricyclic guanidines and the evolution of the strategy for the total synthesis of linked tricyclic guanidines corresponding to the proposed constitution and revised relative configuration of batzelladine F.