370 GHEMISTBY OF THE LEUCOMAINS. 



cold alcohol is very slight, about 1 : 1000. It dissolves in acids and 

 alkalis without decomposition, and from solutions in the latter it 

 can be precipitated by passing carbonic acid, or by the addition of 

 acetic acid. The aqueous solution possesses a neutral reaction. 



The free base can be heated up to 150° without suffering decom- 

 position, but above this temperature it sublimes, and partially de- 

 composes, with evolution of hydrocyanic acid. When heated with 

 potassium hydrate to 200° it yields ammonia and potassium cyanid. 

 Heated with water to 200° it decomposes into carbonic acid, formic 

 acid, and ammonia, and in this respect it agrees with adenin (page 

 342). The properties of Strecker's sarkin agree closely with those 

 of adenin-hypoxanthin ; and, inasmuch as the latter has been often 

 described as hypoxanthin, it is very desirable that the properties of 

 hypoxanthin be redetermined. 



When evaporated with an oxidizing agent, chlorin water and 

 nitric acid, the residue is said to give on contact with ammonia 

 vapors a rose-red color (Weidel test). Kossel, however, has shown 

 that this is due to the presence of xanthin, and that pure hypoxan- 

 thin does not give either the murexid test or the xanthin reaction. 

 According to Strecker, concentrated nitric acid converts hypoxanthin 

 into a nitro compound, which in turn, by the action of a reducing 

 agent, is changed into xanthin. This statement has not been con- 

 firmed either by Fischer or by Kossel. It does not give a green color 

 with sodium hydrate and chlorid of lime — distinction from xanthin 

 (page 392). Potassium permanganate when added to an acid solu- 

 tion of the base is very slowly decolored and hence can be used for 

 its purification (Kossel). 



Like adenin (page 352), when evaporated with bromin water and 

 nitric acid on a water-bath it gives a residue which with alkalis turns 

 red, whilst nitric acid alone, as given above, has no effect (Kossel). 

 An additional similarity to adenin is seen in its behavior to zinc and 

 hydrochloric acid. The addition of sodium hydrate after reduction 

 produces a red color (page 352) which is not as pronounced as in the 

 case of adenin (Fischer).^ 



For the behavior of hypoxanthin and other bases to Drechsel's 

 reaction, see p. 353. With copper sulphate and sodium bisulphite it 

 forms a whiter, more flocculent precipitate than adenin, soluble in 

 250,000 parts of hot water (Kriiger), Its solubility and properties 

 are about the same as those of the adenin compound. 0.5 per cent., 

 and even stronger solutions, are not precipitated in the cold by 

 copper sulphate and sodium hyposulphite. It is, however, precipi- 

 tated on heating, whereas uric acid is not. It is, therefore, possible 

 to separate uric acid from adenin and hypoxanthin by precipitating 

 the latter two bases in hot solution with copper sulphate and sodium 

 hyposulphite. The method, however, is of little practical value, 

 'Berichte, 30,2230, 2241. 



