New Alkaloids and Polyketides from the Marine Sponge-Derived Fungus Penicillium sp. SCSIO41015

The sponge-derived fungus Penicillium sp. SCSIO41015 cultured on solid rice medium yielded twenty-one compounds (1–21), including two new alkaloids (1 and 2) and one new pyrone derivative (3). Their structures were elucidated by analysis of 1D/2D NMR data and HR–ESI–MS. Their absolute configurations were established by single-crystal X-ray diffraction analysis and comparison of the experimental with reported specific rotation values. Compound 16 exhibited selective cytotoxic activity against the human gastric cancer cells MGC803, with IC50 value of 5.19 μM. Compounds 9 and 18 showed weak antibacterial activity against Staphylococcus aureus and Acinetobacter baumannii, respectively, both with MIC values of 57 μg/mL. Furthermore, compound 16 displayed potent antibacterial activity against S. aureus with an MIC value of 3.75 μg/mL.