MICROBIAL TRANSFORMATION OF MARIDOMYCIN III BY SERRATIA MARCESCENS

Abstract

Two transformation products of maridomycin (MDM) III, MDM-S₁ and MDM-S₂ named after Serratia marcescens, were isolated by silica gel chromatography. NMR and IR analysis revealed that MDM-S₁ and -S₂ had no aldehyde group at C-18 on the macrolactone ring, and that the hydroxyl group at C-9 seemed to disappear. Although MDM-S₁ and -S₂ are less active against Gram-positive bacteria than starting MDM III. they are interesting materials in view of the introduction of nitrogen into each molecule, and that the transformation products are produced by Gram-negative bacteria which are thought to be insensitive to macrolide antibiotics.