Identification of O-demethylated and ring-hydroxylated metabolites of methotrimeprazine (levomepromazine) in man
Johnsen, H.; Dahl, S.G.
Drug Metabolism and Disposition the Biological Fate of Chemicals 10(1): 63-67
1982
ISSN/ISBN: 0090-9556 PMID: 6124386 Document Number: 194527
Nonenzymatic FeCl2-catalyzed oxidation of methotrimeprazine (levomepromazine) yielded three ring-hydroxylated derivatives that had different GC retention times but almost identical mass spectra. Two of these, together with O-desmethylmethotrimeprazine, were identified by combined GC/MS in enzymatically hydrolyzed urine from four psychiatric patients, who had been treated with oral doses of methotrimeprazine. The mass chromatograms indicated that the three metabolites were formed in similar amounts. Small amounts of three other metabolites were also found in the urine after enzymatic hydrolysis. These were identified as O-desmethyl-N-monodesmethylmethotrimeprazine and two monohydroxy-N-monodesmethyl derivatives that had different GC retention times. None of those metabolites were found in unconjugated form in the urine.