Discovery of olimycin E from Streptomyces sp. 11695.

A new natural product olimycin E (1), together with two known compounds of divergolide R (2) and olimycin B (3), were obtained from the marine-derived Streptomyces sp. 11695. The structures of 1-3 were established on the basis of HRESIMS as well as 1D and 2D NMR datasets. The absolute configuration of 1 is identified as 4 R, 6S, 7S, 10 R by comparison the experiment ECD with that of the theoretical ECD. Antibacterial results showed that compound 2 have antibacterial activities against Staphylococcus aureus and MRSA with the MIC values of 32 µg/mL, respectively.