Identification of the microsomal oxidation metabolites of rutaecarpine, a main active alkaloid of the medicinal herb Evodia rutaecarpa

Rutaecarpine is a quinazolinocarboline alkaloid of the medicinal herb Evodia rutaecarpa and shows a variety of pharmacological effects. Four oxidation metabolites of rutaecarpine were prepared from 3-methylcholanthrene-treated rat liver microsomes. These metabolites had an [M + H](+) ion at m/z 304. The structures of metabolites were identified by comparison of their liquid chromatograms and mass, absorbance, and H-1 NMR spectra with those of synthetic standards. Rutaecarpine was metabolized by microsomal enzymes to form 3, 10, 11-, and 12-hydroxyrutaecarpine. The formation of 10-hydroxyrutaecarpine was highly induced by a cytochrome P450 1A inducer, 3-methylcholanthrene. (c) 2005 Elsevier B.V. All rights reserved.