Biotransformation of Tranylcypromine in Rat Liver Microsomes

Metabolism of tranylcypromine (TCP) in rat liver microsomes was studied in vitro using fortified microsomal preparations. As well as unlabeled TCP, two deuterium labeled analogs, TCP-phenyl-$d_{5}$ and TCP-cyclopropyl-$d_{2}$ were used and GC/MS employed which was then metabolized to cinnamaldehyde and hydrocinnamyl alcohol. Schiff bases of TCP with hydrocinnamaldehyde and acetaldehyde were detected and possibility of the metabolic formation of N-ethylidene TCP was proposed. In addition, acetophenone (benzoylacetic acid), benzaldehyde, benzoic acid, and benzyl alcohol were detected as the metabolites. Chemical decomposition studies suggested that parts of the oxidized products might be derived by air oxidation processes. A potential metabolite assumed to be N-ethylidene-1, 2-dihydroxy-3-phenylpropanamine oxide was also detected.