Two new polyketone derivatives from the mangrove endophytic fungus <i>Aspergillus sp.</i> GXNU TH4b

Two new polyketones, exserone B (<b>1</b>) and cytosporone F (<b>2</b>), along with three known metabolites, were isolated from the mangrove endophytic fungus <i>Aspergillus</i> TH4b. The structures of <b>1</b> and <b>2</b> were determined by detailed NMR, and MS spectroscopic data. The absolute configurations of <b>1</b> and <b>2</b> were determined by single crystal X-ray diffraction analysis and the combination of experimental ECD and computational ECD, respectively. Compounds <b>1-2</b> have strong inhibitory activity against citrus Psyllid (<i>Diaphorina citri</i>) with 95.4% and 93.7% lethal at 1000 mg/kg.