New Prenylxanthones from the Deep-Sea Derived Fungus Emericella sp SCSIO 05240

Four new prenylxanthones, emerixanthones A-D (1-4), together with six known analogues (5-10), were isolated from the culture of the deep-sea sediment derived fungus Emericella sp. SCSIO 05240, which was identified on the basis of morphology and ITS sequence analysis. The newstructures were determined by NMR (H-1, C-13 NMR, HSQC, HMBC, and H-1-H-1 COSY), MS, CD, and optical rotation analysis. The absolute configuration of prenylxanthone skeleton was also confirmed by the X-ray crystallographic analysis. Compounds 1and 3 showed weak antibacterial activities, and 4 displayed mild antifungal activities against agricultural pathogens.