Macluracochinones A-E, antimicrobial flavonoids from Maclura cochinchinensis (Lour.) Corner

The phytochemical investigation of the fruit and leaf extracts of Maclura cochinchinensis (Lour.) Corner (Moraceae) resulted in the isolation and identification of four undescribed isoflavones (macluracochinones A-D) and one undescribed flavone (macluracochinone E), together with 24 known compounds. The structures of the undescribed compounds were elucidated using nuclear magnetic resonance (NMR) and high-resolution electrospray ionization time-of-flight mass spectrometry (HRESITOFMS) experiments. Gancaonin M, lupiwighteone, lupalbigenin, warangalone, auriculatin, and millexatin F displayed good antibacterial activities against Gram-positive bacteria with MIC values in the range of 1–8 μg/mL. Lupalbigenin showed strong activities against methicillin-resistant Staphylococcus aureus (MRSA) and S. aureus with the same MIC value of 1 μg/mL.