A New Eudesmane Sesquiterpenoid from the Marine-Derived Fungus Penicillium sp. HK1-22

new eudesmane-type sesquiterpenoid, artemihedinic acid N ( 1 ), together with four known compounds, aspterric acid ( 2 ), two naphtho- γ -pyrones, peninaphones A ( 3 ) and B ( 4 ), and a diphenyl ether ( 5 ), were isolated from the rice medium fermentations of the mangrove rhizosphere soil-derived fungus Penicillium sp. HK1-22. The structure of 1 was determined by combined spectroscopic methods including 1D and 2D NMR spectral data. The antibacterial activities of all isolated metabolites were evaluated.