Uric Acid, and their derivatives. 



29a 



served bj tlae different mode of attachment of the urea residues 

 exhibited in the formula now put forward. The mode of pro- 

 duction from uric acid of allantoine, alloxan, paraban, etc., will 

 be seen by comparison of the preceding formulae. 

 Probably nroxanic acid, C^HgN^Oe, is represented by No. 1 



H H H 



i A A 



i "-!-■* A 



IH- 



while the oxonic acid of Strecker and Medicus,* C.H^NjO,, 

 produced under similar conditions, but showing by its contain- 

 ing only three atoms of nitrogen that it cannot include two 

 complete urea residues like those of uric acid, may perhaps have 

 the structure of No. 2. 

 The basicitv of pseudo-uric acid, C^H.N.O, 



plamed by ass^imiii 

 and in one of them 

 hydroxyl— thus : 



urea residues differently utta 

 of hydrogen taking the pla 



1 (monobasic). 

 -N— H 

 A-0_H 





In xanthine, C^H.N.Oa, whose empirical formula ( 

 that of uric acid only by an atom of oxvgen, we ha 

 aissimdarly attached residues of urea, but the basi( 

 disappears altogether and with it the true acid charr 

 ™ urea itself xanthine is capable of uniting wi 

 srith acids. 



oxides £ 



