Two new lasiodiplodins (1-2) together with three known analogues, were isolated from a mangrove endophytic fungus, Lasiodiplodia sp. 318#. Their structures were established by spectroscopic techniques (1D- and 2D-NMR, HR-ESI-MS, etc.), and electronic circular dichroism. Cytotoxic activities of compounds 1-5 were evaluated in vitro. Compound 4 was the most potent, with IC50 values of 5.29 μM against MMQ, 13.05 μM against GH3. Preliminary structural-activity analysis indicated that the functional group (resorcinol-3-OH) contributed greatly to the binding of Lasiodiplodins to the cytotoxic activities.
Keywords: Lasiodiplodia; Mangrove endophytic fungus; lasiodiplodins.