Maytansinoid compound

Abstract

Antibiotic C-15003 PND of the formula: ##STR1## wherein R is H or alkanoyl containing not more than 5 carbon atoms is produced by contacting a maytansinoid compound with a culture broth, inclusive of a processed matter derived therefrom, of a microorganism belonging to one of the genera Streptomyces and Chainia which is able to transform said maytansinoid compound into Antibiotic C-15003 PND. Antibiotic C-15003 PND is useful as antitumor, antifungal or antiprotozoal agent.

Dependencies are inferred from the claim text.