CHEMISTSY OF THE PTOMAINES.. 219 



method of separation is to precipitate it from alcoholic 

 solution by alcoholic picric acid. The picrate thus ob- 

 tained is, for the purpose of further purification, recrystal- 

 lized from absolute alcohol, then decomposed by extractino; 

 its acid solution with ether (to remove the picric acid) and 

 evaporating the aqueous solution to dryness. The residue 

 is now extracted with alcohol and the alcoholic solution 

 precipitated by alcoholic platinum chloride. The platino- 

 chloride can now be recrystallized from hot water. 



The free base, as obtained by the treatment of the 

 hydrochloride with moist freshly precipitated silver oxide, 

 possesses an extremely repulsive odor, similar to that of 

 human semen. On evaporation of its aqueous solution it 

 yields a gelatinous-like mass, and at the same time slowly 

 decomposes. It does not crystallize when evaporated in a 

 vacuum, and decomposes even under these conditions. The 

 same disagreeable odor is obtained when the hydrochloride 

 is warmed with potassium hydrate. Beiegee (I., 24) re- 

 gards this decomposition-product of neuridine as an oxida- 

 tion product of the original substance. 



The free base is very readily soluble in water, but is 

 insoluble in ether and absolute alcohol ; difficultly soluble 

 in amyl alcohol. It gives white precipitates with mercuric 

 chloride, neutral and basic lead acetates. When distilled 

 with fixed alkali it yields di- and tri-methylamine, thus 

 probably showing some relation to neurine, hence the name 

 neuridine. It does not give Hofmann's iso-nitril reac- 

 tion, but it does not follow from this, as shown under 

 cadaverine, that it may not be a primary diamine. It is 

 isomeric with cadaverine, saprine and gerontine. 



The Hydeochloeide, C5Hj^N"2.2HC1, crystallizes in 

 long needles which are extremely soluble in water and 

 in dilute alcohol, but are insoluble in absolute alcohol, 

 ether, benzol, chloroform, petroleum ether, benzine, amyl 

 alcohol, etc. Its insolubility in absolute alcohol may be 

 used to effect a separation from choline hydrochloride. It 

 can be recrystallized from slightly warm dilute alcohol. 

 Although the pure salt is insoluble in the reagents just 

 given, nevertheless, in the presence of other animal matter 



