Penicinines A and B: two new 2-pyridone derivatives from a marine-derived fungus Penicillium sp. BTBU20218001.

Chemical profiling of the marine-derived fungus Penicillium sp. BTBU20218001 led to the isolation of two new 2-pyridone analogues, designated penicinines A (1) and penicinines B (2), along with five previously reported compounds (3-7). Their structures were determined by combined 1D- and 2D-NMR experiments and HR-ESI-MS, with additional verification by comparison to literature data. All purified compounds (1-7) were screened for antimicrobial screening against three microbial strains. Among the tested isolates, only compound 5 demonstrated moderate inhibitory effects on Candida albicans, giving an MIC value of 25 μg/mL.