Aurafuron A and B, New Bioactive Polyketides from Stigmatella aurantiaca and Archangium gephyra (Myxobacteria)

Abstract

New antibiotic polyketides, named aurafuron A (1) and B (2) were isolated from culture extracts of myxobacteria of the species Stigmatella aurantiaca and Archangium gephyra, strain Ar 10844. By multi-step chromatography 1 and 2 were separated from a variety of other non-related co-metabolites, and their structures elucidated by spectroscopic methods as new 5-alkenyl-3 3(2H)-furanones. Aurafurons inhibited the growth of some filamentous fungi and additionally, aurafuron B was weakly active against few Gram-positive bacteria. Both compounds also showed cytotoxic activity against the mouse fibroblast cell line L929.