Breviane Spiroditerpenoids with Anti-inflammatory and Antiviral Activities from Deep-Sea-Derived Fungus Penicillium...

Twelve new breviane spiroditerpenoids, namely, chrysobreviones A-L (1-12), together with seven structurally related analogues (13-19) were isolated from the EtOAc extract of the fermented cultures of deep-sea-derived fungus Penicillium sp. F59. These structures including absolute configurations were resolved on the basis of extensive analysis of NMR spectroscopic data and HRESIMS, in association with experimental and calculated ECD data as well as the modified Mosher's method. Compound 1 represented the first breviane derivative containing an unusual octahydrodifuro[2,3-b:2',3'-d]furan moiety, while 7 and 9 were the first breviones featuring an epoxy ring and an 18-hydroxymethyl group, respectively. The anti-inflammatory and antiviral activities of compounds 1-19 were evaluated. Compounds 1, 8, 16, and 17 showed inhibitory effects against NO secretion in LPS-activated Raw264.7 macrophage cells with IC₅₀ values ranging from 1.4 to 12.9 μM, while 1 and 7 exhibited antiviral effects against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) omicron subvariant BA.2 pseudovirus with IC₅₀ values of 8.5 and 10.3 μM, respectively.