i 4 4 THE SIMPLER NATURAL BASES 



soluble in water and in alcohol, but not in cold chloroform or in 

 ether ; its aqueous solution is neutral. 



The hydrochloride, C 7 H 13 O 2 N . HC1, crystallises in large prisms and 

 dissolves in 127 parts of cold absolute alcohol at 17-18; it is therefore 

 much more soluble than betaine hydrochloride. 



The acid oxalate, C 7 H 13 O 2 N . C 2 H 2 O 4 , forms needles, insoluble in 

 cold absolute alcohol; m.p. 105-107. 



The picrate, C 7 H 13 O 2 N . C 6 H 3 O 7 N 3 , m.p. 195-196, is only precipi- 

 tated from a concentrated solution. 



The aurichloride, CyH^O^N . HAuCl 4 , precipitated in aqueous solu- 

 tion, soon crystallises and forms characteristic four-sided leaflets of 

 rhombic habit ; m.p. 225 on rapid heating. 



The platinichloride, (C 7 H 13 O 2 N) 2 H 2 PtG 6 , with o, 2 and 4H 2 O, 

 readily soluble in water, insoluble in alcohol; m.p. indefinite at 210- 

 220. 



Mercuric chloride causes a precipitate in solutions of the hydro- 

 chloride (best in alcoholic solution), but not in those of the free base. 



Stachydrine methyl and ethyl esters are only soluble in acid solu- 

 tion. 



Betonicine and Turicine. 



The hydrochloride of betonicine is less soluble in absolute alcohol 

 than the hydrochloride of turicine, but the free bases have a reverse 

 order of solubility. 



Betonicine, C 7 H 13 O 3 N + H 2 O has []D= - 36*60 and decomposes 

 at 243-244. Turicine [a] has D = +36*26 and decomposes at 249. 

 Betonicine hydrochloride gave [a] D = - 2479 and turicine hydro- 

 chloride [a] D = +24*65. 



Betonicine aurichloride decomposes at 242, that of turicine at 232. 

 Betonicine platinichloride crystallises with 2H 2 O and decomposes at 

 226, turicine platinichloride contains only iH 2 O and decomposes at 

 223. Both bases heated with zinc dust give a pyrrole reaction with 

 pine wood. 



Trimethyl-histidine. 



Reuter found this base in the arginine fraction, Kutscher curiously 

 enough in the lysine fraction. It is best isolated as aurichloride. 



The base from Boletus has [a]o= +41 *i (in the presence of 8 mol. 

 HC1). 



The nitrate forms large transparent plates and octahedra. The 

 monopicrate, C 9 H 15 O 2 N 3 . C 6 H 3 O 7 N 3 . H 2 O, thin felted needles, m.p. 201, 

 is readily soluble in water; the dipicrate, C 9 H 16 O 2 N 8 . 2C 6 H 3 O 7 N 3 . 2H 2 O, 



