A new member of the angucycline family, vineomycin C (3), together with fou
r known metabolites saquayamycin A1 (1), A-7884 (2), rabelomycin (5) and xa
nthomegnin (6) were isolated from microbial extracts. The structures were d
etermined by 1D and 2D NMR techniques and chemical degradation. Compounds 1
similar to 3 and 5 were isolated from a fermentation of Streptomyces sp.,
while 6 was isolated from a fungal fermentation extract. All five compounds
have shown potent inhibitory activity in the inducible nitric oxide syntha
se (iNOS) assay.