Secondary Metabolites by Chemical Screening, 24. Oasomycins, New Macrolactones of the Desertomycin Family

Publisher Website
Google Scholar
Abstract
New macrolactones, named oasomycin A to D (1 to 4), were discovered by a chemical screening in the culture broth of Streptoverticillium baldacii subsp. netropse (strain FH‐S 1625). The structures were established by detailed spectroscopic analysis. The fundamental 42‐membered lactone moiety of oasomycin A and B (1 and 2) is analogous to that of desertomycin A (5), while the oasomycins C and D (3 and 4) are the first representatives of macrolactones bearing a 44‐membered skeleton. These metabolites can be distinguished by side chain modifications at C‐41 or C‐43 as well as the presence of an α‐linked D‐mannose moiety attached to 22‐OH. Due to the structural similarities the oasomycins are integrated into the desertomycin family. In vitro testing by using the HEP‐G2 cell assay showed oasomycin A (1) to be an inhibitor of de novo cholesterol biosynthesis.