New Polyketide and Butenolide Derivatives from the Mangrove Fungus Aspergillus spelaeus SCSIO 41433

Two new racemic mixtures, including a polyketide, (±)-penilactone F (1), and a butenolide, (±) phenylbutyrolactone IIa (2), were isolated from the mangrove sediment-derived strain Aspergillus spelaeus SCSIO 41433. Additionally, 20 known compounds were isolated, including four penicillin-like compounds (11-14), three alkaloids (15-17), one sesquiterpene (18), and four phenolic acids (19-22). Their structures were elucidated through NMR spectroscopy, HRESIMS, X-ray diffraction, and ECD calculations. In the PDE4 inhibitory activity and anticancer cell activity assays, compounds 2, 3, 5, 8, 9, 11-14, and 16 exhibited weak PDE4 inhibitory activity at a concentration of 10 µM, Compound 11 demonstrated potent inhibitory effects against six cancer cell lines (MDA-MB-231, MDA-MB-435, HCT116, SNB-19, PC3, and A549), with IC₅₀ values ranging from 3.4 to 23.7 µM.