BASES OF CINCHONA -BARK. 441 



5. Papaverine, C 21 H 21 N0 4 . Colorless prisms ; fusing 

 point, 147 ; insoluble in water, difficultly soluble in 

 cold alcohol and ether, more easily in the hot liquids. 



6. Narceine, C 23 H 29 K0 9 . White, fine needles, of a 

 silky lustre ; fusing point, 145. But slightly soluble 

 in cold water and cold alcohol, more easily in the 

 hot liquids, insoluble in ether. Is colored blue by 

 iodine, like starch, if care be taken to avoid an excess 

 of iodine. Taken in small quantity it causes a very 

 sound and quiet sleep. 



In addition to these, in some varieties of opium, 

 there occur, in exceed ingty small quantity, other alka- 

 loids : meconidine, C 21 H 23 ^0 4 ; laudanine, C 20 H 25 ITO 3 ; 

 codamine, C 19 H 23 N0 3 ; cryptopine, C 21 H 23 K0 5 ; protopine, 

 C 10 H 19 N0 5 ; laudanosine, C 21 H 27 M) 4 ; hydrocotarnine, 

 C 12 II 15 l$r0 3 ; lanthopine, C 23 H 25 1TO 4 ; opianine, metamor- 

 phine^ and rhoeadine, C 21 H 2 W0 6 . The latter base is also 

 contained in Papaver rhoeas. 



5. Bases of Cinchona-bark. 



In true cinchona-barks there occur principally two 

 alkaloids : 



Quinine, C^IP^O 2 , and 

 Cinchonine, C 20 H 24 N 2 0, 



in varying quantities. Calisaya bark (China regid) 

 contains the most quinine (between 2 and 3 per cent. 

 quinine, and 0.2-0.3 cinchonirie); Huanaco bark con- 

 tains the most cinchonine"* (2.24 per cent, cinchonine, 

 and 0.85 per cent, quinine). A few other alkaloids, as, 

 for instance, aricine, C 23 H 26 N 2 4 , paytine, C 21 H 24 N 2 -f 

 II 2 0, occur in only a few cinchona-barks ; other bases, 

 isomeric with quinine and cinchonine, as quinidine, 

 cinchonine, do not appear to occur in the plants origin- 

 ally, but to be formed from quinine and cinchonine by 

 a process of transformation. 



* The base, huanocine, which has been prepared from this bark, is 

 probably identical with cinchonine. 



