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Two new phenolic glucosides, including a new O -glycoside ( 1 ) and a new C -glycoside ( 2 ), were isolated from a marine-derived fungus Aspergillus sp. The structures of new compounds were elucidated through interpretations of spectroscopic evidence and high-resolution electrospray ionization mass spectrometry. The hexose unit of 1 was identified as β -D-glucose by comparison with an authentic sample via HPLC after acid hydrolysis and derivatization. All compounds were evaluated for their ability to inhibit LPS-induced NO production in RAW264.7 macrophages, but none of them displayed significant activity.

Three new meroterpenoids, asperaustins A-C ( 1 - 3 ), and seven known analogues ( 4 - 10 ) were isolated from a marine-derived Aspergillus sp. fungus. The structures and absolute configurations of these new compounds were unequivocally determined by extensive spectroscopic analyses and single-crystal X-ray diffraction analyses. Asperaustin A ( 1 ) possesses an unusual spiro[4.5]deca-3,6-dien-2-one moiety with a unique 5/6/6/6/5 pentacyclic skeleton. The absolute configurations of austinoneol A ( 7 ) and precalidodehydroaustin ( 9 ) were determined by single-crystal X-ray diffraction analyses using Cu Kα radiation for the first time.

A chemical investigation of the secondary metabolites of a marine-derived Aspergillus sp. led to the isolation and characterization of 13 phenolic compounds, including 10 new compounds (1-10). Seven new compounds (1-7) are unusual phenolic C-glycosides, while the other new compounds (8-10) are structurally related aglycones. The chemical structures of these new compounds were elucidated by 1D and 2D NMR and HRESIMS spectroscopic analyses. The absolute configurations of these new C-glycosides were determined by comparison of experimental electronic circular dichroism spectra with those of calculated ones. In addition, the anti-inflammatory activities of these compounds were evaluated, and compound 9 significantly inhibited nitric oxide production with an IC 50 value of 6.0 ± 0.5 μM in lipopolysaccharide-induced RAW264.7 cells. Moreover, compound 9 also showed anti-inflammatory activity by inhibiting the NF-κB-activated pathway.