PD 116,152, a new phenazine antitumor antibiotic. Structure and antitumor activity

A new, highly substituted phenazine with antitumor activity was isolated from the culture broth of a Streptomyces sp. This compound, whose structure was determined by spectroscopic methods and verified by X-ray diffraction analysis, was found to be methyl 6-formyl-4,7,9-trihydroxy-8-methyl-1-phenazinecarboxylate.