i L 



nstituiional formidce of Urea^ 



* 1. Uric acid, Gibbs.f 



H H H 



I I 1 I 



-H c— G— C— C=C 



C— i I— c— c 



-C-N 



i I i 





While each of these formulae possesses advantages for the 

 explanation of certain cases of decomposition and certain 

 derived products, an attentive study will show, I think, that 

 all are more or less defective as to accounting in the simplest 

 way for the well known basicitv of uric acid itself, bringing it 

 into harmony with the general structure of non-nitrogenous 

 organic acids, recognizing a close relationship to the 3-carbon 

 series, and preserving as far as possible simplicity and sym- 

 metry in the supposed arrangement of the atoms. 



In connection with the formula I propose it may be noticed : 

 that it does account for uric acid being dibasic ; that it derives 

 it as directly as possible from a residue of the 3-carbon mesox- 

 alic acid ; that it explains simply most of the observed decom- 

 positions of the acid; that it perhaps affords a reason, in the 

 direct linking together of the two urea residues as well as 

 their attachment to the acid nucleus, for the comparative 

 stability of uric acid ; and that it also suggests a cause of the 

 difficulty of reproducing this substance artificially, since in the 

 attempt to form a salt of urea with a non-nitrogenous acid and 

 then remove water the basic hydroxyl might be eliminated 

 and the normal acid type destroyed, whereas this type is pre- 



* Lehrb. d. org. Chem., 1868, 800. f This Journal, Nov., 1868, xlvi, 293. 



t Ajin. der Chem., clxxv, 243 ; where moat of the formulae above quoted are 



§ Chem. C 



t Aug., 1875, 4 



