Three new polyketides, cylindrocarpones A-C (1-3), two new pyridone alkaloids, cylindrocarpyridones A-B (5-6), a new pyrone cylindropyrone (7), together with seven know compounds were isolated from the endophytic fungus, Cylindrocarpon sp., obtained from the tropical plant Sapium ellipticum. The structures of the new compounds were elucidated by extensive analysis of their spectroscopic data (1D and 2D NMR, HRESIMS). The absolute configuration of 19-O-methyl-pyrrocidine B (13) was confirmed by X-ray analysis. All isolated compounds were screened for their cytotoxic and antibacterial activities. Pyrrocidine A (12) exhibited potent cytotoxicity against the human ovarian cancer cell line A2780 with an IC50 value of 1.7 μM. 19-O-Methyl-pyrrocidine B (13) showed moderate antibacterial activity against S. aureus ATCC25923 and ATCC700699 with MIC values of 50 and 25 μM, respectively.
Keywords: Alkaloids; Cylindrocarpon sp.; Cytotoxicity; Polyketides.
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