Macrolides of the bafilomycin family produced by Streptomyces sp. CS

Abstract

Five new 16-membered macrolides (1-5), belonging to the bafilomycin subfamily, were isolated from the fermentation broth of Streptomyces sp. CS, a commensal microbe of Maytenus hookeri. Their structures including relative configurations were elucidated based on NMR data and analysis of single crystal X-ray diffraction data. The cytotoxicities of compounds 1-5 on the MDA-MB-435 cell line were analyzed by the MTT method and the IC(50) values were found to be 4.2, 4.5, 5.5, 3.8 and 11.4 μM, respectively.