Diastereoselective Synthesis of the A‐B‐C Tricyclic Ring Structure of Stemocurtisine

Abstract

Abstract The diastereoselective synthesis of the A‐B‐C tricyclic ring structure of the Stemona alkaloid stemocurtisine is described. This tricyclic precursor to the natural product was obtained in 19 steps from a known vinyl iodide. Attempts to prepare the C‐3a–C‐11 ether moiety of this alkaloid through a photochemically induced oxidative cyclization method were unsuccessful because of the cleavage of the A‐ring.