The title mol-ecule, C(13)H(11)NO(3), a natural compound extracted from Phellodendron chinense, exhibits a near planar framework: the mean deviations from the furo[2,3-b]quinoline ring system and from the whole mol-ecule (not including the H atoms) are 0.006 and 0.062 Å, respectively.
Three limonoids and five alkaloids were isolated from the chloroform layer of the MeOH extract of the bark of Phellodendron amurense (Rutaceae). The structures of the compounds isolated were determined to be obacunone (1), limonin (2), 12alpha-hydroxylimonin (3), gamma-fagarine (4), oxyberberine