Four New Nanaomycins Produced by Streptomyces hebeiensis Derived from Lichen.

Four new nanaomycins (1 - 4), together with two known compounds, nanaomycin αA (5) and nanaomycin βA (6) were isolated from a fermentation broth of Streptomyces hebeiensis derived from lichen. The structures of the new nanaomycins 1 - 4 were established using comprehensive NMR spectroscopic data analysis as well as UV, IR, and MS data. The antimicrobial activities of 1 - 6 were evaluated against Gram-positive bacteria and fungus. Compounds 5 and 6 showed antimicrobial activities against the test microorganisms, while 1 - 4 were inactive at 100 μg/ml.