CHEMICAL BASIS OF THE ANIMAL BODY. 



905 



small scales. When pure it is a colorless powder, very insoluble in water, requir- 

 ing 1 500 times its bulk for solution at 100 C. Insoluble in alcohol and ether, it 

 readily dissolves in dilute acids and alkalies, forming crystallizable compounds. 

 [Figs. 246, 247, 248.] 



Hypoxanthin by oxidation becomes xanthin. Both these bodies as well as the 

 following, guanin and carnin, are evidently closely allied to uric acid ; indeed, uric 

 acid by the action of sodium-amalgam may be converted into a mixture of xanthin 

 and hypoxanthin. 



Preparation. It is obtained from urine and the aqueous extract of muscles by 

 a process similar to that for hypoxanthin, and is then separated from the latter by 

 the action of dilute hydrochloric acid ; this separation depends on the different 

 solubilities of the hydrochlorides of the two bodies. For further information see 

 Neubauer and Vogel. 1 



Carnin. C 7 H 8 N 4 3 . 



Discovered by Weidel 2 in extract of meat, of which it constitutes about 1 per 

 cent, 



It crystallizes in white masses composed of very small, irregular crystals ; it is 

 soluble with difficulty in cold, more easily soluble in hot water, insoluble in alcohol 

 and ether. Its aqueous solution is not precipitated by normal lead acetate, but is 

 by the basic acetate of this metal. It unites with acids and salts, forming crystal- 

 line compounds. 



Preparation. Is found in the precipitate caused in extract of meat by basic 

 acetate of lead. 3 



This body possesses an interesting relation to hypoxanthin, into which it maybe converted by 

 the action either of nitric acid or, still better, of bromine. 



Guanin. C 5 H 5 N 5 0. 



First obtained from guano, but recently observed as occurring in small quanti- 

 ties in the pancreas, liver, and muscle extract. 



[FiG. 249. 



[Fio. 250. 



Guanin Hydrochloride. C 5 H 5 N 5 O.HC1 + H 2 O. 

 (After Kvihne.)] 



Guanin Nitrate. 



(After Kiihne.)] 



It is a white amorphous powder, insoluble in water, alcohol ether, and ammo- 

 nia. It unites with acids, alkalies, and salts to form crystallizable compounds. 

 [Figs. 249, 250.] 



Preparation. From guano by boiling successively with milk of lime and caustic 

 soda, precipitating with acetic acid, and purifying by solution in hydrochloric acid 

 and precipitation by ammonia. 



1 Harn- Analyse, ed. viii. (1881), S. 26. Also the literature quoted above on hypoxanthin. 



2 Ann. d. Chem. u. Pharm., Bd. clviii. S. 365. 3 see Weidel, op. cit. 



