Mechanism of formation of mercapturic acids from (1-bromoethyl)benzene and (2-bromoethyl)benzene in the rat

Abstract

1. Three hypotheses have been proposed for the mechanism of metabolism of alkylhalides to hydroxy-alkylmercapturic acids, two of which involve the intermediate step of dehydrohalogenation and formation of an epoxide.

2. After injection of (1-bromoethyl)benzene in rat, the only mercapturic acid appearing in the urine was N-acetyl-S-1 -phenylethylcysteine. After injecting (2-bromoethyl)benzene in the rat only N-acetyl-S-2-phenylethylcysteine and N-acetyl-S-(2-phenyl-2-hydroxyethyl)cysteine were found in the urine.

3. Since the principal mercapturic acid formed from both styrene and styrene oxide could not be detected in the urine of rats receiving either 1- or 2-bromoethyl benzene, the intermediate formation of styrene or styrene oxide from the arylalkylhalides does not occur.