A New Isoflavone from the Fruits of Ficus Auriculata and Its Antibacterial Activity.

A new isoflavone (Z)-5,7,4 '-trihydroxy-3 '-[3-hydroxy-3-methyl-1-butenyl] isoflavone (1) together with seven known isoflavones (2-8) were isolated from the fruits of the Ficus auriculata. Their structures were established on the basis of 1 D, 2 D-NMR spectroscopic data and HR-ESI-MS analysis. All compounds were evaluated for their antibacterial activities against five pathogenic bacteria in vitro. Compounds 3 and 4 exhibited significant antibacterial activities against five pathogenic bacteria with the MIC values ranging from 1.25 to 20 mu g/mL.