Cytotoxic Dibohemamines D–F from a Streptomyces Species

Three dimeric analogues of bohemamines, dibohemamines D–F (1–3), together with dibohemamine A (4), were isolated from Streptomyces sp. CPCC 200497. Their structures were solved using a combination of mass spectrometry, 1D and 2D NMR spectroscopy, and CD. Dibohemamines D and E were new dimeric analogues of bohemamines, and dibohemamine F was a known compound obtained previously by semisynthesis. Dibohemamine F displayed potent cytotoxicity against cancer cell lines A549 and HepG2 with IC₅₀ values of 1.1 and 0.3 μM, respectively. Dibohemamines D and E showed moderate cytotoxicity against cancer cell lines A549 and HepG2.