WF11899A, B and C, novel antifungal lipopeptides. II. Biological properties

Abstract

WF11899A, B and C, novel water-soluble lipopeptides related to the echinocandins, possess potent anti-Candida activities. The IC50s of the compounds against four clinical isolates of Candida albicans ranged from 0.004 to 0.03 μg/ml by microbroth dilution assay. These compounds mildly suppressed the growth of Aspergillus fumigatus and A. niger. WF11899A, B and C showed a potent in vivo anti-Candida activity. Particularly, WF11899A was superior to cilofungin, and equal to fluconazole. 1, 3-β-glucan synthase was inhibited by these compounds at the IC50s of 0.7, 0.7 and 1.8μg/ml for WF 11899A, B and C, respectively. However, they hemolysed mouse red blood cells in vitro at the concentration of 62 μg/ml. © 1994, JAPAN ANTIBIOTICS RESEARCH ASSOCIATION. All rights reserved.