Dimeric 1,4-Benzoquinone Derivatives with Cytotoxic Activities from the Marine-Derived Fungus Penicillium sp. L129

Two new dimeric 1,4-benzoquinone derivatives, peniquinone A (1) and peniquinone B (2), a new dibenzofuran penizofuran A (3), and a new pyrazinoquinazoline derivative quinadoline D (4), together with 13 known compounds (5-17), were isolated from a marine-derived fungus Penicillium sp. L129. Their structures, including absolute configurations, were elucidated by extensive spectroscopic data and electronic circular dichroism calculations. Compound 1 exhibited cytotoxicity against the MCF-7, U87 and PC3 cell lines with IC50 values of 12.39 mu M, 9.01 mu M and 14.59 mu M, respectively, while compound 2 displayed relatively weak cytotoxicity activities against MCF-7, U87 and PC3 cell lines with IC50 values of 25.32 mu M, 13.45 mu M and 19.93 mu M, respectively. Furthermore, compound 2 showed weak quorum sensing inhibitory activity against Chromobacterium violaceum CV026 with an MIC value of 20 mu g/well.