Fusarisolins A–E, Polyketides from the Marine-Derived Fungus Fusarium solani H918

Abstract

Five new (fusarisolins A⁻E, <b>1</b> to <b>5</b>) and three known (<b>6</b> to <b>8</b>) polyketides were isolated from the marine-derived fungus <i>Fusarium</i> <i>solani</i> H918, along with six known phenolics (<b>9</b> to <b>14</b>). 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 <b>1</b> and <b>2</b> are the first two naturally occurring 21 carbons polyketides featuring a rare β- and γ-lactone unit, respectively. All isolates (<b>1</b> to <b>14</b>) were evaluated for their inhibitory effects against tea pathogenic fungus <i>Pestalotiopsis theae</i> and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) synthase gene expression. Compound <b>8</b> showed potent antifungal activity with an ED₅₀ value of 55 μM, while <b>1</b>, <b>8</b>, <b>13</b>, and <b>14</b> significantly inhibited HMG-CoA synthase gene expression.