Abstract: AimTo identify the main metabolites of hydrochloride 4-methyl-piperazine-1- carbodithioc acid 3-cyano-3,3-diphenyl-propyl ester (TM208) in rats. MethodsRat feces, urine and plasma samples were collected after ig 500 mg·kg^-1 TM208, then the samples were extracted and concentrated using ethyl acetate. The treated samples were analyzed by HPLC-ESI/ITMSⁿ. The structures of metabolites were elucidated according to the rules of drug metabolism and disposition in vivo and the characteristic fragmentation behaviors of TM208 in ESI-ITMSⁿ. ResultsEight phase I metabolites were identified existing in rat feces, five of them were also found in rat urine and plasma, but no phase II metabolite was found. ConclusionThe HPLC-ESI/ITMSⁿ method is rapid, highly sensitive and specific and it is suitable for the identification of TM208 and its metabolites in rats.