Isolation of novel antifungal antibiotics, ezomycins A1, A2, B1 and B2.

Abstract

From ezomycin complex produced by a strain of Streptomyces were isolated four components named ezomycins A₁ (C₂₆H₄₀N₈O₁₆S), A₂ (C₁₉H₂₈N₆O₁₃), B₁ (C₂₆H₃₉N₇O₁₇S) and B₂ (C₁₉H₂₇N₅O₁₄) which are new pyrimidine nucleosides. Ezomycins A₁ and B₁ containing L-cystathionine were found to be responsible for specific antimicrobial activity of the complex against Sclerotinia and Botrytis species.