GUANINE. 171 



Origin. So little is known of this substance in reference 

 either to its chemical nature, or its occurrence in the animal body, 

 that we cannot offer any conjecture regarding its genesis. 



Many attempts have been made to convert uric acid into 

 xanthine, but they have all been unsuccessful. 



HYPOXANTHINE. 



[Since the publication of the first volume of Professor Lehmann's 

 work, Scherer* has discovered the occurrence of a white, crystalline, 

 pulverulent substance in the spleen, and in the heart of man and 

 the ox. On analysis it yielded : 



Carbon "^ 44*257 



Hydrogen 3*219 



Nitrogen .... .... .... .... 40*820 



Oxygen 11'704 



100-000 



Its formula is C 5 H 2 N 2 O. Hence it is xanthine minus 1 equi- 

 valent of oxygen. Scherer has given it the name of hypoxanthine. 



G. E. D.] 



G UANINE.-z=C 10 H 5 N 5 O 2 . 



Chemical Relations. 



Properties. This body is a yellowish-white crystalline powder, 

 devoid of odour or taste, which can bear a temperature of 220 

 without loss of weight, is insoluble in water, alcohol, and ether, 

 has no action on vegetable colours, and dissolves freely in hydro- 

 chloric acid and caustic soda ; it unites with acids, forming unstable 

 salts ; on mixing its sulphate with a very large quantity of water, 

 there is a separation of the hydrate of guanine, which does not lose 

 its combined water till it is raised to a temperature of 100. 



Composition. This body was discovered by Bodo linger :f it was 

 at first mistaken for xanthine, but subsequently, by analysis of the 

 free body and its salts, it was ascertained to be a distinct, weak 

 base. According to the formula deduced from his analyses, it 

 consists of: 



* Ann. de Ch. u. Pharm. Bd. 73, S. 328. 



t Ann. d. Ch. u. Pharm. Bd. 51, S. 395 ff, and Bd. 58, S. 28-31 ; Pogg. Ann. 

 Bd. 65, S. 222-239, and Ann. d. Ch. u. Pharm. Bd. 59, S. 58-73. 



