Cytochrome P450 2D6 inhibitory constituents of Lunasia amara

► From Indonesian medicinal plant Lunasia amara, two new acridone alkaloids, 5-hydroxygraveroline (1) and 8-methoxyifflaiamine (2), were isolated together with 12 known ones. Among the 14 compounds isolated, 5-hydoroxygraveoline (1) and lunamarine (3) showed moderate inhibition selective to CYP2D6 with IC50 values of 4.7 and 1.8 μM, respectively.