CINATRINS, A NOVEL FAMILY OF PHOSPHOLIPASE A₂ INHIBITORS

I. TAXONOMY AND FERMENTATION OF THE PRODUCING CULTURE; ISOLATION AND STRUCTURES OF CINATRINS

Abstract

Cinatrins A, B, C₁, C₂ and C₃, a family of phospholipase A₂ inhibitors were isolated from the fermentation broth of Circinotrichum falcatisporum RF-641. They were found to be novel spiro-γ-dilactones and γ-lactones derived from 1, 2, 3, 5-tetra or 1, 2, 3(or 1, 2, 4)-trihydroxypentadecane1, 2, 3-tricarboxylic acids. Structures were elucidated by MS and NMR studies and chemical transformations. The structure of cinatrin C₃ was confirmed by X-ray crystallographic analysis, and its absolute configuration was determined by comparison of the CD spectra with related compounds.