Structural investigation of the antibiotic sporaviridin. VII. Structural studies on the constituent pentasaccharides, viridopentaoses.

Abstract

Sporaviridin is a basic and water-soluble antibiotic produced by Streptosporangium viridogriseum. During separation and purification of N-acetylsporaviridin, we found that this derivative was hydrolyzed by aqueous ammonia used as the eluent for column chromatography to yield glycosidic compounds containing an aglycone and three pentasaccharides, designated as viridopentaoses A, B and C. The purfication of these compounds was performed as shown in Chart 2. They were concluded to be novel heteropentasaccharides (1A, 1B and 1C) containing two or three amino sugars, on the basis of chemical degradations and spectroscopic studies.