The metabolism of naphthalene in rabbits

Abstract

Naph-thalene dissolved in warm liquid paraffin was adminis-tered to [male] rabbits by stomach tube. The urine excreted during the 48 hrs. following contained 2 metabolic products of naphthalene, 1 of which (not isolated) was a soluble compound yielding naphthalene on acidification. The 2nd was extracted from the acidified urine by chloroform, which was evaporated, the crude material purified and finally recrystallized from aqueous alcohol. It was an organic acid of formula C15H15O3NS ; M.P. 170.5-171[degree]; a 1% soln. in abs. alcohol had [[alpha]]''D[long dash]25[degree]. The presence of one acetyl group in the molecule was proved by micro-acetyl estimation; after decomposition by boiling with dilute H2SO4, an amphoteric compound, C13H13O2NS, was isolated, which proved to be 1-[alpha]-naphthylmercapturic acid, a compound not previously described but which is analogous to the [rho]-bromophenyl mercapturic acid excreted after bromobenzene feeding. It is suggested that, since naphthalene requires cysteine for its detoxication, the cataract produced in rabbits by repeated doses of naphthalene may result from depriving the lens of cysteine.