The metabolic fate of tridemorph in rats

A single oral dose of [14C]tridemorph was partly, but rapidly absorbed by rats. Most of the radioactivity was excreted with a half-life of about 15 h. During 5 days, 42.6% was excreted in the urine, 46.7% in the faeces, 1.5% in the expired air and 3.4 % was still retained. 24 % was excreted in the 48 h bile. Sequential wholebody autoradiography indicated that much of the radioactivity was confined to the gastrointestinal tract, liver and kidneys. There was no unexpected uptake of radioactivity. Urinary metabolites were more polar than tridemorph and were also detected in the bile and faeces. The major metabolite in 24 h urine, accounting for 22.3% of the dose appeared to be a side-chain hydroxylated derivative. Cleavage of the morpholine ring was limited to about 1.5 % of the dose.