Indole Alkaloids from the Cigar Tobacco-Derived Endophytic Fungus Aspergillus oryzae and Their Antibacterial Activity

Two new indole alkaloids, 6-(4-methoxyphenoxy)-4-methoxy-2-methyl-1 H -indole ( 1 ) and 6-(3,5-dimethoxyphenoxy)-4-methoxy-2-methyl-1 H -indole ( 2 ), along with four known ones ( 3–6 ), were isolated from the fermentation products of the cigar tobacco-derived endophytic fungus Aspergillus oryzae . Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1 and 2 were evaluated for their antibacterial and antioxidant activities. The results showed that compounds 1 and 2 exhibited good anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity with IZD of 22.4 ± 2.4 and 24.6 ± 2.2 mm, respectively.