New N-methyl-4-quinolone alkaloid and citrinin dimer derivatives from the sponge-derived fungus Penicillium sp. SCSIO 41303

Abstract

Four new N-methyl-4-quinolones (1–4) and a new citrinin dimer derivative (10) with fourteen known compounds (5–9, 11–19) were isolated from the sponge-derived fungus Penicillium sp. SCSIO41303. Their structures and absolute configurations were elucidated by extensive spectroscopic analysis, electronic circular dichroism (ECD) calculation, and X-ray single-crystal diffraction. Most of the isolated compounds were evaluated for their cytotoxic, antibacterial, anti-virus, and enzyme inhibitory activities against acetylcholinesterase (AChE), and pancreatic lipase (PL). Compounds 2 and 11 exhibited enzyme inhibition activity against PL with IC50 values of 24.6 and 7.2 μg/mL, respectively. Besides, compound 11 showed enzyme inhibition activity against AChE with IC50 value of 16.5 μg/mL. Compound 15 showed moderate inhibition activities with 52.2% at the concentration of 50 μg/mL against PL and antibacterial activity against Staphylococcus aureus displaying diameter of about 10 mm.