New anthracycline antibiotics, auramycins and sulfurmycins. II. Isolation and characterization of 10 minor components (C approximately G).

Following the discovery of new anthracycline antibiotics, auramycins A and B and sulfurmycins A and B, we found 10 minor analogues of auramycins and sulfurmycins, C, D, E, F and G, from the culture broth of a mutant strain of Streptomyces galilaeus OBB-111 and prepared 2 analogues as the chemical derivatives from auramycin G and sulfurmycin G. All analogues have a sugar moiety at C-7 position of the aglycones. These analogues exhibit activities against Gram-positive bacteria and P388 leukemia.