Fusarisolins A⁻E, Polyketides from the Marine-Derived Fungus H918.

Five new (fusarisolins A⁻E, to ) and three known ( to ) polyketides were isolated from the marine-derived fungus H918, along with six known phenolics ( to ). Their structures were established by comprehensive spectroscopic data analyses, methoxyphenylacetic acid (MPA) method, chemical conversion, and by comparison with data reported in the literature. Compounds and are the first two naturally occurring 21 carbons polyketides featuring a rare β- and γ-lactone unit, respectively. All isolates ( to ) were evaluated for their inhibitory effects against tea pathogenic fungus and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) synthase gene expression. Compound showed potent antifungal activity with an ED value of 55 μM, while , , , and significantly inhibited HMG-CoA synthase gene expression.