CHEMISTRY OF THE LEUCOMAINES. 307 



leafy or needle-shaped glittering: crystals which have the 

 composition C^H^N.OHgClj + Hp. 



The following table of Beuhns illustrates the analogy 

 existing between the mercury compounds of adenine and 

 hypoxanthine and similar derivatives of ammonium : 



Ammonium. Adenine, Hypoxanthine. 



NH,Hs;Cl OsH.NjHkCI C.HjN.OHgClf+HjjO) 



A brom-hypoxanthine compound corresponding to that of 

 adenine has not been obtained. 



Benzyl-hypoxanthine, CsH^N^O.CHj.CjHs, was obtained 

 by Thoiss by the action of nitrous acid on benzyl-adenine. 

 It forms a white crystalline mass which under the micro- 

 scope consists of thin plates. It is easily soluble in hot 

 water, dilute alcohol, and in acetic ether ; insoluble in ether 

 and chloroform. It melts at 280°. It appears, as Kossei, 

 has pointed out, that adenine and hypoxanthine contain a 

 group, CjH^N^, which he named adenyl. The formation of 

 the benzyl derivatives of these two bases shows that the 

 hydrogen atom which is replaced occurs in the adenyl and 

 not in the imido group. According to this view adenine is 

 to be considered as adenylimide fCjH^N^.NH) and hypo- 

 xanthine as adenyloxide (CjH^N.jO). 



Phosphomolybdic acid precipitates hypoxanthine from 

 acid solution, and in general it gives the ordinary alkaloidal 

 reactions. 



It is not precipitated by ammoniacal basic lead acetate. 

 Copper acetate does not precipitate it in the cold, but does 

 on boiling. This fact has been made use of in the isolation 

 of hypoxanthine. Mercuric chloride, as well as mercuric 

 nitrate, produces a flocculent precipitate. 



Altogether, in its behavior to reagents it resembles xan- 

 thine to a very considerable degree. The two can be 

 separated, however, by the different solubilities of the 

 hydrochlorides in water, and more especially of the silver 

 salt in nitric acid. 



Physiological Action. — 25-100 mg. begin to act on frogs 



