Messrs Fenton and Wilks, Formation of uric acid derivatives. 547 



Formation of uric acid derivatives. By Dr Fenton and 

 W. A. R. Wilks, B.A., Gonville and Gains College. 



[Read 23 May, 1910.] 



The condensation of urea with dihydroxymaleic acid, or its 

 derivatives, would appear likely to be of interest from a physio- 

 logical standpoint owing to the peculiar manner in which this 

 acid is produced by oxidation in presence of traces of iron. The 

 authors are making a study of these condensation-products and it 

 has already been shown that the acid itself condenses with urea 

 to give isoiminazalone and, probably, the aldehyde of hydantoic 

 acid. When the acid is gently oxidised, mesoxalic semi-aldehyde 

 is obtained; this might be expected to yield uric acid by action of 

 urea but, under the conditions employed, the result is glycoluril, 

 a substance closely related to allantoin. By oxidising the acid 

 with bromine, dihydroxytartaric acid is obtained; this when acted 

 upon by urea in presence of acetic anhydride is found to yield 

 a product which appears to be identical with acetyl dialuric acid, 

 recently obtained by Behrend and Friedrich from dialuric acid 

 itself [Annalen 1906 (344) 1.] It gives a violet precipitate 

 with baryta water and, when evaporated with nitric acid, an intense 

 murexide reaction. According to Ascoli and Izar [^Zeit. Physiol. 

 Ghem. 1909 (62) 347], dialuric acid and urea under the influence 

 of liver extract can give rise to uric acid, and it would therefore 

 appear that the synthesis of the uric acid might be effected from 

 dihydroxytartaric and urea by the changes indicated. In alcoholic 

 solution, dihydroxytartaric acid and urea yield the crystalline 

 salt C4H6O8 . 200 (NH2)2; when this is heated to about 100° it 

 breaks up, probably quantitatively, into carbon dioxide, urea and 

 hydantoin. 



The fate of uric acid in the dog. By Harold Ackroyd, M.B. 

 (Communicated by Mr W. E. Dixon.) 



[Read 6 June, 1910.] 



The liver of dogs when perfused with normal saline solution 

 produces a small quantity of allantoin. When sodium urate is 

 added to the perfusion fluid, a part of the sodium urate is 

 destroyed: part of this can be recovered as allantoin but not the 

 whole. No urea could be isolated from such a perfusion fluid. 

 The liver of a dog has not the power to destroy allantoin. 



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