44-HOMOOLIGOMYCINS A AND B, NEW ANTITUMOR ANTIBIOTICS FROM Streptomyces bottropensis: PRODUCING ORGANISM, FERMENTATION, ISOLATION, STRUCTURE ELUCIDATION AND BIOLOGICAL PROPERTIES

Oligomycin antibiotics, 44-homooligomycin A (NK86-0279 II) and B (NK86-0279 I) are newly discovered antitumor antibiotics with the substitution of ethyl for methyl at carbon 26. They were isolated from the culture broth of Streptomyces bottropensis NK86-0279. The structure of these two compounds was deduced by spectroscopic and X-ray crystallographic analyses. These antibiotics showed potent antitumor activities against various tumor cells in vitro, and were active against Colon 26 carcinoma in vivo. Although they showed no activity at 1, 000 μg/ml against Gram-positive and Gram-negative bacteria and yeast, they have antifungal activity.