330 HYPOXANTHINE. XANTHINE. [BOOK I. 



78 parts of boiling and 300 parts of cold water ; it is soluble in dilute 

 acids and alkalies. It forms compounds with acids, bases, and metallic 

 salts. Certain of the latter have already been referred to; a com- 

 pound with platinum, having the composition of C 5 H 4 N 4 . HC1 . PtCl 4 , 

 may be mentioned, as well as one with copper which is formed when 

 a solution of hypoxanthine is boiled with solution of cupric acetate ; 

 this compound is a brownish flocculent body insoluble in water, which 

 does not admit of purification ; it yields however impure hypoxanthine 

 when it is decomposed by H a S. 



Relations Hypoxanthine is very closely related to xanthine 



of Hypoxan- and to uric acid, as would appear probable from an exami- 

 thine to other nation of their formulae. 



bodies< Uric acid . . C 5 H 4 N 4 3 . 



Xanthine . . C 5 H 4 N 4 O,. 

 Hypoxanthine . . C 6 H 4 N 4 O. 



From the two first of these bodies, hypoxanthine can be obtained 

 by the action of sodium amalgam; when oxidized with nitric acid 

 it yields xanthine. 



Proportion According to Neubauer 1 the flesh of the ox contains 



of hypoxan- 0*022 per cent, and that of the rabbit 0'026 per cent, 



thine found in of hypoxanthine. 

 muscle. 



Xanthine. C 5 H 4 N 4 O 2 . 



Xanthine a This const i tuen * f muscle was first discovered by 



rare consti- Marcet 2 , as a constituent of a urinary calculus, and by 

 tuent of uri- him called xanthic oxide. It was afterwards analyzed 

 nary calculi, by Liebig and Wohler 3 and linger 4 . It has been 

 of guano and discovered in guano 5 , and in some cases in the urine 

 of man 6 and the lower animals 7 . 



Preparation ^ n preparing hypoxanthine that body was directed 



from muscle, to be precipitated with ammoniacal solution of nitrate 

 Neubauer's of silver, and the precipitate dissolved in nitric acid of 



method. S p g r j.-^ j t wag s t a ted that when the acid cooled 



the compound of hypoxanthine and silver nitrate separated. Now 

 the first precipitate (viz. that thrown down by ammoniacal silver 

 nitrate) contains, in addition to hypoxantlnne, a silver compound 

 of xanthine; the latter compound being more soluble in nitric acid of 



1 Neubauer, Zeitschrift f. anal. Chem. vi. 33. 



2 Marcet, Essay on 'the Chemical History and Chemical Treatment of Calcvlons 

 Disorders. London, 1819. 



3 Liebig und Wohler, Poggendorff's Ann. Vol. XLI. p. 393. 



4 Unger, Ann. d. Chem. u. Pharm. Vol. LVIII. p. 18. 



e Unger and Pbipson, Chem. News, Vol. vi. 1862, p. 16. 



6 Bence Jones, Quart. Journ. of Chem. Soc. Vol. xv. p. 78. 



7 Weiske, "Xanthin und Harnsaure im Ham eines kranken Scbafbockes." 

 Zcitechr.f. Biol. xi. p. 254. 



