Four 4-hydroxy-ff-pyrones including three new ones named nipyrones A-C (1-3) together\nwith one known analogue germicidin C (4) were discovered from a marine sponge-derived fungus\nAspergillus niger cultivated in a solid rice culture. Their structures and absolute configurations were\nelucidated through a combination of spectroscopic data and electronic circular dichroism (ECD)\ncalculations as well as comparison with literature data. Compounds 1-4 were evaluated for their\nantibacterial activities against five pathogenic bacteria (Staphylococcus aureus, Escherichia coli, Bacillus\nsubtilis, methicillin-resistant Staphylococcus aureus, and Mycobacterium tuberculosis). Compound 3\nshowed promising activity against S. aureus and B. subtilis, with minimum inhibitory concentration\n(MIC) values of 8 ffg/mL and 16 ffg/mL, respectively, and displayed weak antitubercular activities\nagainst M. tuberculosis, with MIC value of 64 ffg/mL, while compounds 1 and 2 exhibited moderate\nantibacterial effcacy against four pathogenic bacteria with MIC values of 32-64 ffg/mL.
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