O-Alkylazoxymycins A-F, Naturally Occurring Azoxy-Aromatic Compounds from Streptomyces sp. Py50

Six new azoxy-aromatic compounds (o-alkylazoxymy-cins A-F, 1-6) and two new nitrogen-bearing phenylvaleric/ phenylheptanoic acid derivatives (o-alkylphemycins A and B, 7 and 8) were isolated from Streptomyces sp. Py50. Their structures were elucidated based on HRESIMS, NMR, UV spectroscopic analyses, and X-ray crystallographic data. O-Alkylazoxymycins A-F (1-6) are the first natural examples of azoxy compounds with the azoxy bond attached to the ortho-position of the phenylheptanoic acid or phenylvaleric acid moiety. Compounds 1, 5, and 6 were active against Epidermophyton floccosum with MIC50 values ranging from 10.1 to 51.2 mu M. A plausible biosynthetic pathway of 2 and 3 was proposed.

Automated summary

Six new azoxy-aromatic compounds and two new nitrogen-bearing phenylvaleric/phenylheptanoic acid derivatives were isolated from Streptomyces sp. Py50 and their structures were elucidated. Compounds 1, 5, and 6 exhibited anti-fungal activity against Epidermophyton floccosum with MIC50 values ranging from 10.1 to 51.2 μM. A possible biosynthetic pathway for compounds 2 and 3 was proposed.