Studies on the metabolites of Zygosporium masonii. Part I. Structure of zygosporin A

Abstract

A cytotoxic antibiotic, zygosporin A, was isolated from the culture filtrate of Zygosporium masonii and its stereostructure was elucidated as (7E,13E)-(3S,3aR,4S,6S,6aR,10S,12R,15R,15aR)-15-acetoxy-3-benzyl-3,3a,4,5,6,6a,9,10,12,15-decahydro-6,12-dihydroxy-4,10,12-trimethyl-5-methylenecycloundeca[d]isoindole-1,11(2H)-dione (XXXIII) by chemical degradation and X-ray analysis. It has been reported that cytochalasin D is identical with zygosporin A.