Isolation and structure elucidation of 7,8-dideoxy-6-oxo-griseorhodin C produced by Actinoplanes ianthinogenes.

A novel product, isolated from a culture broth of Actinoplanes ianthinogenes fermented for producing purpuromycin, was purified and its structure established on the basis of physico-chemical data and chemical reactions. The new product resulted to be structurally related to griseorhodins, a group of hydroquinonic antibiotics obtained from Streptomyces californicus. This compound showed a weak activity against Gram-positive and resulted inactive against Gram-negative bacteria and Candida albicans.