LEPTOMYCINS A AND B, NEW ANTIFUNGAL ANTIBIOTICS

II. STRUCTURE ELUCIDATION

Abstract

The structures of new antifungal antibiotics, leptomycins A and B produced by Streptomyces sp. ATS1287 were determined as described below (Fig. 1) on the basis of their spectral and chemical character. Leptomycins have unique structures which belong to the unsaturated, branched-chain fatty acids with δ-lactone rings at the end.