348 VII. ACIDS, AMIDES, ALDEHYDES AND HYDROCARBONS 



Young-^' first isolated the mercapturic acid derivative of naphthalene from 

 rabbit urine in 1934, and their work has been confirmed by others for 

 (^Qgg244 g^j^d fQj. rabbits. -^^ 



S— CHs-CH-COOH 



NH-COCH, 



Naphthalene a-Naphthylmercapturic acid 



The Formation of L-a-Naphthylmercapturic Acid in the MetaboUsm of Naphthalene in 



Rabbits 



c'. 1 ,2-Dihydro-2-Naplithol as an Oxidation Product: Bourne and 

 Young, ^^^ have suggested that the parent substance of naphthalene, first 

 obtained by Baumann and Herter-^^ when acidified "naphthalene urine" 

 was distilled, is 1 ,2-dihydro-2 (or j8)-naphthol. Bourne and Young-^^ and 

 StekoP^® confirmed the fact that acidified urine yields naphthalene under 

 these conditions. Baumann and Herter-^* were of the opinion that this 

 proved the fact that free naphthalene was excreted in the urine. How- 

 ever, Bourne and Young^^^ demonstrated that naphthalene was not formed 

 when "naphthalene urine" was made alkaline before being distilled. Pure 

 l,2-dihydro-2-naphthol, which was first synthesized by Bamberger and 

 Lodter,-^^ has been shown to be converted to naphthalene by mineral acids, 

 and presumably it is the substance giving rise to naphthalene when the 

 acidified solution is distilled. According to Bourne and Young, -^^ a con- 

 siderable portion of this compound may be excreted. A similar type of 

 product has been demonstrated in the urine following the administration 

 of anthracene."" 



1 ,2-Dihydro-2-naphthol 



The Conversion of i^2-Dihydro-2-Naphthol to Naphthalene by Heating in the Presence 



of Mineral Acids^**'^" 



d'. l,2-Dihydroxy-l,2-Dihydronaphthalene as a Product of Naph- 

 thalene Metabolism : Lesnik and Nencki-^^ were the first to call attention 

 to the presence of dihydrox3aiaphthalenes as oxidation products of this 



2" H. R. Ing, M. C. Bourne, and L. Young, Biochem. J., 28, 809-810 (1934). 

 *6^ E. Baumann and E. Herter, Z. phijsiol. Chem., 1, 244-269 (1877). 

 2«6 E. Bamberger and W. Lodter, Ann., 288, 74-133 (1895). 



