Facile Total Syntheses of Putative and Revised Structures of Pethybrene

Abstract

The structural identity of pethybrene was confirmed as theoretically proposed 6-5-5 tricyclic structure through total syntheses of two putative structures. The originally proposed structure 1 was synthesized in 13 steps via Intramolecular Pauson-Khand reaction to form the triquinane skeleton and the newly proposed structure from a theoretical study 2 was obtained from a known [2+2] cycloaddition product in 3 steps.