358 VII. ACIDS, AMIDES, ALDEHYDES AND HYDROCARBONS 



from the urine of rabbits after the feeding of 1,2,5,6-dibenzanthracene. 

 Rats and mice were also shown to excrete a dihydroxy-l,2,5,6-dibenzan- 

 thracene in the urine-*' after treatment with the carcinogen, but it differed 

 from that excreted by the rabbit. It is now known-*' that the dihydroxy 

 compound synthesized by rats and mice has the hydroxyl groups on posi- 

 tions 4' and 8' as shown by the identity of this product with dihydroxy- 

 benzanthracene prepared synthetically by Cason and Fieser.^*^^ Boyland 

 and co-workers^°^ suggested that the diphenol from rabbit urine was most 

 probably the 3.7-, 4,8-, or 3,8-dihydroxy compound. Williams'''° is of the 

 opinion that the compound most probably is 3,7-dihydroxy-l,2,5,6- 

 dibenzanthracene. 



OH 



^^ 



1 ,2,5,6-Dibenzanthracene 4 ',8 '-Dihydroxy-1 ,2,5,6- 



dibenzanthracene 



The formation of 4',8'-Dihydroxydibenzanthracene in Rats and Mice after the Admin- 

 istration of Dibenzanthracene"" 



The 4' ,8' -dihydroxy derivative of dibenzanthracene is probably not 

 excreted as a glucuronide or as a component of the ethereal sulfate fraction, 

 by rats, mice, or monkeys, as no increase in the amount of this compound 

 which can be extracted results from autoclaving the urine. ^*' Further- 

 more, Dobriner et al^^^ were unable to obtain any evidence of the forma- 

 tion of a mercapturic acid derivative. 



The dihydroxy compound isolated from rabbit urine was found to have 

 no carcinogenic activity^* '•^'"•^°' in mice. This would indicate that the 

 rabbit possesses the ability to convert a carcinogen into a non-carcinogen 

 in the body. According to Abels et al.^'^'^ and also Baumann et a/.,^"^ 



»2 J. Cason and L. F. Fieser, /. Am. Chem. Soc, 62, 2681-2687 (1940). 



303 E. Boyland, A. A. Levi, E. H. Mawson, and E. Roe, Biochem. J., 35, 184-191 

 (1941). 



304 J. C. Abels, A. T. Gorham, S. L. Eberhn, R. Halter, and C. P. Rhoads, /. Exptl. 

 il/ed., 76, 143-161(1942). 



306 C. A. Baumann, E. G. Foster, and P. R. Moore, J. Biol. Chem., 1^2, 5976-08 

 (1942). 



