METHYLTHIO METABOLITES OF NAPHTHALENE EXCRETED BY RAT

  • 1 January 1978
    • journal article
    • research article
    • Vol. 20  (3) , 509-530
Abstract
Eight methylthio metabolites were found as urinary products of the metabolism of naphthalene in the rat. One was 1-methylthionaphthalene. A 2nd was a methylthio analog of the dihydrodiol, and a 3rd was naphthalene substituted with 1 hydroxyl and 1 methylthio group. Two compounds with common structural elements were found; 1 of these was prepared by synthesis from anti-1,2:3,4-naphthalene dioxide and 1 from 1.beta.,2.alpha.-dihydroxy-3.alpha., 4.alpha.-epoxy-1,2,3,4-tetrahydronaphthalene by reaction with 2-keto-4-methylthiobutyric acid or with methionine. Each of these compounds contained 1 methylthio group and 3 hydroxyl groups substituted on a tetrahydronaphthalene structure. Two metabolites with 2 methylthio groups and 2 hydroxyl substituents on a tetrahydronaphthalene ring were also detected; 1 of these was prepared by synthesis from the dioxide. The most likely metabolic origin of these methylthio metabolites is through the reaction of epoxides (including the diepoxide) with a nucleophile which may be methyl mercaptan, 2-keto-4-methylthiobutryic acid, or methionine.