Polyketides and Alkaloids from the Fungus Penicillium sp.

: The marine-derived fungus SCZ-1 was cultured on rice solid medium. The fermented materials was extracted using ethyl acetate to afford an extract, which was separated by repeated column chromatography to afford three polyketides and five alkaloids, including 2 new polyketides ( 1 and 2 ). The known compounds were identified to be penipyrol A ( 3 ), cyclopenin ( 4 ), cyclopenol ( 5 ), terretrione D ( 6 ), viridicatol ( 7 ), and viridicatin ( 8 ). The structures of 1 and 2 were determined by extensive analyses of spectroscopic data (1D and 2D NMR, and HRESIMS). The absolute configuration of 2 was assigned by comparison of the experimental ECD spectrum with calculated ECD spectrum. Compound 1 , bearing a two-carbon side chain at C-2, is seldom found among natural isocoumarins. All metabolites were screened for their inhibitory effects toward  -glucosidase, only compound 8 showed weak activity with an IC 50 value of 548  M.