A New Cyclic Peptide from Betel Nut Endophytic Fungus Alternaria sp. RW-AL.

A new cyclic peptide alternarin A (1), along with seven known compounds, alternariol (2), sulfated derivative of alternariol (3), alternariol methyl ether (4), altenuene (5), 2,5-dimethyl-7-hydroxychromone (6), diaporthein A (7), isopterocarpolone (8), were isolated from the betel nut endophytic fungus Alternaria sp. RW-AL. The structure of 1 was elucidated by 1D and 2D NMR spectra as well as HR-ESI-MS analysis. Compounds 1, 4, and 5 showed definite antibacterial activities against Staphylococcus aureus ATCC 6538 and Bacillus subtilis ATCC 6633. [ABSTRACT FROM AUTHOR]