New Fusarochromanone Derivatives from the Marine Fungus Fusarium equiseti UBOCC-A-117302

Two new fusarochromanone derivatives, deacetylfusarochromene (<b>1</b>) and deacetamidofusarochrom-2',3-diene (<b>2</b>), along with the previously reported metabolites fusarochromanone TDP-2 (<b>3</b>), fusarochromene (<b>4</b>), 2,2-dimethyl-5-amino-6-(2'<i>E</i>-ene-4'-hydroxylbutyryl)-4-chromone (<b>5</b>), fusarochromanone (<b>6</b>), (-)-chrysogine (<b>7</b>), and equisetin (<b>8</b>), were isolated from the marine fungus <i>Fusarium equiseti</i> UBOCC-A-117302. The structures of the compounds were determined by extensive spectrometric (HRMS) and spectroscopic (1D and 2D NMR) analyses, as well as specific rotation. Among them, <b>2</b> and <b>5</b> showed inhibition of three protein kinases with IC₅₀ values ranging from 1.42 to 25.48 μM. Cytotoxicity and antimicrobial activity of all isolated compounds were also evaluated. Six fusarochromanone derivatives (<b>1</b>-<b>6</b>) exhibited diverse activities against three cell lines, RPE-1, HCT-116, and U2OS (IC₅₀ values ranging from 0.058 to 84.380 μM). Equisetin (<b>8</b>) showed bactericidal activities against <i>Bacillus cereus</i> and <i>Listeria monocytogenes</i> (MBC values of 7.8 and 31.25 µM, respectively), and bacteriostatic activity against <i>Enterococcus faecalis</i> (MIC value of 31.25 µM). Compounds <b>2</b> and <b>4</b> showed bacteriostatic activities against <i>Listeria monocytogenes</i> (MIC of 125 µM).