Abstract
The characterization and quantitation of a new urinary metabolite, M2, from rats orally given atenolol, a β-adrenergic blocking drug, are described. 4-(2-Hydroxy-3-isopropylaminopropoxy) phenylglyoxylic acid amide was synthesized as an authentic sample by an unequivocal route. The structure of M2 was definitively established by direct comparison with the synthetic specimen. Determination of M2 in urine was achieved by means of selected ion monitoring (SIM) using [3H6]-atenolol as an internal standard. The amount of M2 excreted in urine was estimated to be 1.04% of the dose.
