Isolation and structure determination of inostamycin, a novel inhibitor of phosphatidylinositol turnover

Abstract

In the course of screening for phosphatidylinosicol turnover inhibitors, we found that a culture broth of a Streptomyces strain strongly inhibited the incorporation of inositol into phosphatidylinositol and its phosphates. The active principle was isolated from the broth through EtOAc extraction, cc, centrifugation partition chromatography, and crystallization. Spectroscopic and crystallographic analysis revealed that it has a novel polyether structure, and we named it inostamycin. Inostamycin inhibited phosphatidylinositol turnover with an IC50 of 0.5 μg/ml in cultured A431 cells. © 1990, American Chemical Society. All rights reserved.