C1IKMISTKY <>K THK I' T > M AI N" KS . 231 



The I'K-KATK, rjl n N<>.< ',,IL( N< >,).,< )H, is obtained in 

 broad prisms, which melt at 1!)."). It is tin- only salt 

 suitable for manipulation-. 



In describing WENCKi's collidine (page 196) it waa stated 

 that tyrosin might IK- looked upon as the source of that 

 base. It would seem, however, to be more appropriately 

 the parent snltstanee of mydine, inasmuch as it decomposes 

 on being heated to 270 into carbonic aeid and oxypheuyl- 

 ethvlamine, C 8 H U NO. The change that takes place can 

 IM- represented by the equation : 



r TT 



C ..\CH ! .CHNH,.C0 2 H = C.,. CHjNIIi + co ,. 



TYROSIN. OxyPlIlNYL-ETIITI.AMINE. 



A BASE, ( 1 5 II U NO,, was isolated by E. and H. SAL- 

 KOWSKI (188.S) from deeomposinj; fibrin and meat. In its 

 composition it is isomeric with Ix'taine anhydride. It is 

 extremely soluble in water, very difficultly so in alcohol, 

 insoluble in ether, and possesses a semen-like odor ami 

 saline taste. The aqueous solution, which is not alkaline 

 in reaction, yields on evaporation a stellate crystalline mass, 

 which on standing over sulphuric acid becomes a white 

 powder, which melts at 15<). It dissolves silver oxide, 

 l)iit not cupric hydrate, thus apparently indicating that it 

 is not an amido acid. Moreover, it does not give a pre- 

 cipitate or blue coloration with copper acetate, or anuno- 

 niacal silver nitrate. It thus di tiered from the then known 

 amido-valerianie acids, its isomers. Recently, however 

 (1891), GABRIEL and A0CHA1* showed that ''-amido-vale- 

 rianic acid agrees with this base in its reactions to copper 

 and silver oxide, copper acetate, and ammoniacal silver 

 nitrate. The >-old salt of the synthetic base possessed (lie 

 same composition as that of SALKOWSKI, ami melted at 



The identity of this base with ' s -amido-valerianic acid 

 (homopiperidinie acid) would seem to IM- established, and 

 as such it is regarded. Its structure, then, is represented by 



NH r CII 2 .CIL.< I 



