Identification of 5-(3,4-Dihydroxyphenyl)-5-Phenylhydantoin as a Metabolite of 5,5-DiphenyIhydantoin (Phenytoin) in Rats and Man

Abstract

5-(3,4-Dihydroxyphenyl)-5-phenylhydantoin, a diphenolic metabolite of diphenylhydantoin, has been identified by use of gas chromatography/mass spectrometry in urine from rats and man. The metabolite is present mainly in the conjugated form. It is probably formed in vivo by dehydrogenation of the dihydrodiol 5-(3,4-dihydroxy-1,5-cyclohexadien-1-yl)-5-phenylhydantoin.