Hybrid flavan-chalcones, aromatase and lipoxygenase inhibitors, from Desmos cochinchinensis.

Hybrid flavan-chalcones, desmosflavans A (1) and B (2), together with three known compounds, cardamonin (3), pinocembrin (4) and chrysin (5), were isolated from leaves of Desmos cochinchinensis. Cardamonin (3) and chrysin (5) exhibited potent antioxidant activity with 15.0 and 12.2 ORAC units. Desmosflavans A (1) and B (2), pinocembrin (4), and chrysin (5) were found to be inhibitors of aromatase with respective IC50 values of 1.8, 3.3, 0.9, and 0.8 μM. Desmosflavan A (1) inhibited lipoxygenase with the IC50 value of 4.4 μM. Desmosflavan A (1) exhibited cytotoxic activity with IC50 values of 0.29-3.75 μg/mL, while desmosflavan B (2) showed IC50 values of 1.71-27.0 μg/mL.