Anthracycline metabolites from baumycin-producing Streptomyces sp. D788. II. New anthracycline metabolites produced by a blocked mutant strain RPM-5

A daunorubicin-blocked mutant strain RPM-5 derived from a new baumycin-producing Streptomyces sp. D788 accumulated a major precursor metabolite D788-1 (10-carboxyl-13-deoxocarminomycin) and nine minor metabolites in the culture broth. Five among them were new with a substituent at C-10 or the altered side chains at C-9. Isolation, purification and identification of all anthracycline metabolites produced by strain RPM-5 are described with their antitumor activities against L1210 cells.