Total synthesis of calothrixin B via sequential Sonogashira coupling/copper-catalyzed oxidative cyclization†
Abstract
A total synthesis of the antimalarial indolo[3,2-j]phenanthridine alkaloid calothrixin B is reported. The key intermediate, ketoester 11, was assembled using sequential Sonogashira coupling and intra/intermolecular fashioned copper-catalyzed oxidative cyclization reactions.