Liquid chromatography-mass spectrometry for analysis of a novel beta(2)-adrenoceptor agonist trantinterol and its metabolites in beagle dog urine.

A liquid chromatography-tandem mass spectrometry method was developed for the identification of metabolites of trantinterol, a novel beta(2)-adrenoceptor agonist, in beagle dog urine. The separation of metabolites was performed on a reversed-phase C(8) column using 0.1% formic acid in water and methanol (70 : 30, v/v) as the mobile phase. The structural information and elemental information of metabolites were acquired by an electrospray ionization tandem mass spectrometer and a quadrupole time-of-flight mass spectrometer, respectively. A total of 13 metabolites were detected and characterized on the basis of their tandem MS/MS fragmentation patterns. The accurate masses of nine metabolites were determined and two metabolites were further confirmed by comparing with reference standards. The metabolic pathways of trantinterol in beagle dog are proposed.