Antibacterial Polyketides Isolated from the Marine-Derived Fungus Fusarium solani 8388

Seven new polyketides named fusarisolins F-K (1-6) and fusarin I (7) were isolated from the marine-derived fungus Fusarium solani 8388, together with the known anhydrojavanicin (8), 5-deoxybostry coidin (9), and scytalol A (10). Their structures were established by comprehensive spectroscopic data analyses, and by comparison of the ¹H and ¹³C NMR data with those reported in literature. Fusarisolin F (1) contained both a dichlorobenzene group and an ethylene oxide unit, which was rare in nature. In the bioassays, fusarisolin I (4), fusarisolin J (5), and 5-deoxybostry coidin (9) exhibited obvious antibacterial activities against methicillin-resistant Staphylococcus aureus n315 with MIC values of 3, 3, and 6 μg/mL, respectively. Fusarisolin H (3) and fusarisolin J (5) showed inhibitory effects against methicillin-resistant Staphylococcus aureus NCTC 10442 with the same MIC value of 6 μg/mL. With the exception of 5, all other compounds did not show or showed weak cytotoxicities against HeLa, A549, and KB cells; while fusarisolin J (5) demonstrated moderate cytotoxicities against the three human cancer cell lines with CC₅₀ values between 9.21 and 14.02 μM.