328 BACTERIAL POISONS. 



Carnine is not affected by prolonged boiling with concen- 

 trated barium hydrate. Bromine water decomposes it with 

 the evolution ot" gas and the formation of hypoxanthine. 

 This change takes place according to the following equa- 

 tion : 



C 7 H 8 N 4 O 3 + 2Br = C 5 H 4 N 4 O.HBr + CH 3 Br + CO,. 



A similar decomposition into hypoxanthine is brought about 

 by the action of nitric acid, though in this case oxalic acid 

 and a yellow body are formed. When carnine is evaporated 

 with chlorine water containing a little nitric acid, the resi- 

 due, on contact with ammonia, gives a rose-red color 

 (murexide test). This is due, according to WEIDEL, to 

 the formation of hypoxanthine, but it has since been shown 

 that the latter base does not give this reaction, and hence it 

 is due to the production of xanthine, or some similar body. 

 The physiological action of carnine has been examined 

 somewhat by BRUCKE, and according to him it is not very 

 poisonous. The only effect observed, when taken inter- 

 nally, was a fluctuation in the rate of the heart beat, though 

 even this was by no means definite in its nature. 



A BASE, C 4 H 5 N 6 O, was obtained by GAUTIER from 

 fresh musole tissue of beef, according to the method given 

 on page 334, and on account of a resemblance in some of 

 its properties with xanthine, he named it pseudoxanthine. 

 This name is very inappropriate, not only because it differs 

 so much in its empirical Ibrmula from that of xanthine, 

 C 5 H 4 N 4 O 2 , but also -because the term pseudoxanthine has 

 already been applied by SCHUL.TZEN and FILEHNE to a 

 body isorneric with xanthine, which was obtained by the 

 action of sulphuric acid on uric acid. 



The free base forms a light-yellow powder, slightly 

 soluble in cold water, soluble in weak alkali and in hydro- 

 chloric acid. The hydrochloride is very soluble, and it 

 forms stellate prisms with curved faces, which resemble 

 the corresponding salt of hypoxanthine, and to some extent, 

 also, the whetstone-shaped crystals of uric acid. 



Like xanthine, its aqueous solution is precipitated in the 



