CLASSIFICATION 267 



whilst nicotine contains two rings, one a pyridine ring and 

 the other a pyrrolidine ring 



CH 2 CH 2 



CH 2 CH S 



\ / 



NH 



Pyrrolidine 



such as is also found in proline (see p. 316). 



II. Pyrrolidine Alkaloids. This is a small group, com- 

 prising as yet only three alkaloids, namely : 



Hygrine and Kuskhygrine, from the leaves of Erythroxylon 



Coca, and 

 Stachydrine, from the tubers of S tacky s tuberifera* and 



leaves of Citrus vulgaris.^ 



The constitution of Stachydrine is as follows : 



CH 3 CHg 



CO CH CH 2 



I \X 



O N(CH 3 ) 2 



Stachydrine 



showing it to be a dimethyl betaine of pyrrolidine. 



III. Tropane Alkaloids. The alkaloids belonging to this 

 group are derivatives of tropane 



CH 2 



CH CH 



CH CH 



Wl 



2 Urio 



Tropane 



which substance, as may be seen, contains both a six-mem- 

 bered piperidine ring and a five-membered pyrrolidine ring. 



The group includes alkaloids from the four Natural 

 Orders : 



Solanaceae, e.g. Atropine, Hyoscine, Hyoscyamine. 



* Planta and Schulze : "Arch. d. Pharm.," 1893, 305; " Ber. deut. chem. 

 Gesells.," 1893, 26, 939; Schulze and Trier: " Ber. deut. chem. Gesells.," 1909, 

 42, 4654 ; " Zeit. physiol. Chem.," 1910, 67, 59. 



f Jahns: "Ber. deut. chem. Gesells.," 1896, 29, 2065. 



+ For an explanation of the term betaine, see p. 265. 



