ACETYLATION OF S-ALKYLCYSTEINES BY RAT

Rats have been dosed with S-ethyl-, S-propyl-, S-butyl-, S-pentyl- and S-hexyl-cysteine, and the mercapturic acids excreted have been determined by paper and gas-liquid chromatography. N-(Ethyl thioacetyl)glycine is a metabolite of S-ethyl cysteine and has been determined by GLC; the higher cysteines did not form N-alkyl-thioacetylglycine metabolites. Rats dosed with S-butyl- and S-pentyl- cysteines excreted traces of the sulphoxide of the corresponding mercapturic acid. The amounts of mercapturic acid formed by rat liver slices from S-butyl, S-pentyl- and S-hexyl-l-cysteine have been determined. The synthesis and properties of N-(ethyl-, N-(propyl- and N-(butyl-thioacetyl)glycine, and of the sulphoxides of pentyl- and hexyl-mercapturic acid are described. © 1969.