抄録
The metabolism of mepirizole (I) in human urine was studied by labeling the drug with a stable isotope, deuterium. An equimolar mixture of the deuterium labeled mepirizole (II) and its protium counterpart (I) was administered orally to a man. The metabolites were extracted from the pooled urine with CH2Cl2, treated with diazomethane and applied to GC-MS. The ion clusters in the mass spectra were used for detection of the urinary metabolites of I in man. By this technique, three metabolites, 1-(4-methoxy-6-methyl-2-pyrimidinyl)-5-methoxy-3-hydroxymethylpyrazole (III), 1-(4-methoxy-6-methyl-2-pyrimidinyl)-5-methoxypyrazole-3-carboxylic acid (IV) and 1-(4-methoxy-6-carboxy-2-pyrimidinyl)-5-methoxy-3-methylpyrazole (V) were identified in human urine.
