APPLICATION OF DIRECTLY COUPLED HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY NUCLEAR-MAGNETIC-RESONANCE MASS-SPECTROMETRY TO THE DETECTION AND CHARACTERIZATION OF THE METABOLITES OF 2-BROMO-4-TRIFLUOROMETHYLANILINE IN RAT URINE

Directly coupled HPLC-NMR-MS was used to identify the major urinary me tabolite of 2-bromo-4-trifluoromethylaniline in the rat as the sulfate conjugate of 2-bromo-4-trifluoromethyl-6-hydroxyaniline. This metabol ite could not have been fully characterised using HPLC-NMR or HPLC-MS alone as the sulfate group is 'NMR silent' and MS would not have enabl ed the position of substitution on the aromatic ring to have been assi gned, The need to carefully select HPLC solvents for directly coupled HPLC-NMR-MS so that NMR and MS data can both be obtained is also shown .