Isolation and Structure Elucidation of New Metabolites from the Mariana-Trench-Associated Fungus Aspergillus sp. SY2601.

Fungi are important resource for the discovery of novel bioactive natural products. This study investigated the metabolites produced by Mariana-Trench-associated fungus Aspergillus sp. SY2601 in EY liquid and rice solid media, resulting in the isolation and structure determination of 28 metabolites, including five new compounds, asperindopiperazines A-C ( 1 - 3 ), 5-methoxy-8,9-dihydroxy-8,9-deoxyaspyrone ( 21 ), and 12 S -aspertetranone D ( 26 ). Structures of the new compounds were elucidated based on extensive NMR spectral analyses, HRESIMS data, optical rotation, ECD, and 13 C NMR calculations. The new compound 12 S -aspertetranone D ( 26 ) exhibited antibacterial activity against both methicillin-resistant Staphylococcus aureus and Escherichia coli with MIC values of 3.75 and 5 μg/mL, respectively.