PT  - JOURNAL ARTICLE
AU  - M Claesen
AU  - M A Moustafa
AU  - J Adline
AU  - D Vandervorst
AU  - J H Poupaert
TI  - Evidence for an arene oxide-NIH shift pathway in the metabolic conversion of phenytoin to 5-(4-hydroxyphenyl)-5-phenylhydantoin in the rat and in man.
DP  - 1982 Nov 01
TA  - Drug Metabolism and Disposition
PG  - 667--671
VI  - 10
IP  - 6
4099  - http://dmd.aspetjournals.org/content/10/6/667.short
4100  - http://dmd.aspetjournals.org/content/10/6/667.full
SO  - Drug Metab Dispos1982 Nov 01; 10
AB  - To determine whether the hydroxylation of 5,5-diphenylhydantoin (DPH) to 5-(4-hydroxyphenyl)-5-phenylhydantoin (p-HPPH) occurs by an arene oxide-NIH shift process, racemic 5-(4-deuteriophenyl)-5-phenylhydantoin (p-2H-DPH) was subjected to in vivo metabolic experiments in the rat and in man. After enzymatic hydrolysis of the urine, para-hydroxylated metabolites were separated by HPLC. Deuterium retention in the isolated metabolites determined by gas chromatography-mass spectrometry, was 68-72%. The results are interpreted as the predominance of an arene oxide-NIH shift pathway in those two metabolic systems. Induction of rats with phenobarbital or 3-methylcholanthrene showed no effect on the value of deuterium retention.