Urinary metabolites of 3,5-di-(1-[13C]methyl-1-methylethyl)4-hydroxytoluene (BHT-13C) in man.
Butylated hydroxytoluene (BHT) containing the stable isotope 13C was synthesized from 2-[13C]methylpropan-2-ol. A minor constituent of urine following ingestion of BHT-13C by a human volunteer was identified as 3,5-di-(1-[13C]methyl-1-methylethyl)-4-hydroxybenzoic acid, The major metabolite detected was 13C-labeled 5-carboxy-7-(1-carboxy-1-methylethyl)-3,3-dimethyl-2-hydroxy-2,3-dihydrobenzofuran. Detailed spectral analysis provided the basis for structural assignment. No evidence was found for intermediate metabolites leading from BHT-13C to the above compounds. Analysis of one fraction indicated the presence of traces of S-(3,5-di-(1-[13C]methyl-1-methylethyl-4-hydroxy-benzyl)-N-acetylcysteine. Analysis of serum samples by gas chromatography detected only trace quantities of unchanged BHT. No evidence was found for the presence of other nonpolar or unconjugated metabolites.
Urinary metabolites of 3,5-di-(1-[13C]methyl-1-methylethyl)4-hydroxytoluene (BHT-13C) in man. Butylated hydroxytoluene (BHT) containing the stable isotope 13C was synthesized from 2-[13C]methylpropan-2-ol. A minor constituent of urine following ingestion of BHT-13C by a human volunteer was identified as 3,5-di-(1-[13C]methyl-1-methylethyl)-4-hydroxybenzoic acid, The major metabolite detected was 13C-labeled 5-carboxy-7-(1-carboxy-1-methylethyl)-3,3-dimethyl-2-hydroxy-2,3-dihydrobenzofuran. Detailed spectral analysis provided the basis for structural assignment. No evidence was found for intermediate metabolites leading from BHT-13C to the above compounds. Analysis of one fraction indicated the presence of traces of S-(3,5-di-(1-[13C]methyl-1-methylethyl-4-hydroxy-benzyl)-N-acetylcysteine. Analysis of serum samples by gas chromatography detected only trace quantities of unchanged BHT. No evidence was found for the presence of other nonpolar or unconjugated metabolites.