Oxazolomycins produced by and their cytotoxic activity.

Six oxazolomycins (1-6) were isolated from the fermentation broth of a soil-borne bacterial strain, . The structures of the new compounds, oxazolomycins D-F (1-3) and glaucumycins A, B (6a/6b), were elucidated by detailed spectroscopic data analysis. Oxazolomycins 1, 2, 4, and 5 demonstrated weak or modest cytotoxic activities against four human cancer cell lines, with IC values ranging from 10.