604 CONSIDERATION OF CARBON COMPOUNDS. 



CH CH 2 CH 2 



/% /\ /\ 



HC CH H 8 C CH 2 H 2 C CHa 



II I II I I 



HC CH H,C CH 2 H 2 C CHC 3 H T 



N NH NH 



Pyridine. Piperidine. Coniine. 



Piperidine has been made by adding 6 atoms of hydrogen to pyri- 

 dine by means of sodium and alcohol ; coniine, which is propyl-piperi- 

 dine, was the first true alkaloid prepared artificially. 



Piperin, Piperina, C 17 H 19 NO 3 =-- 283.04. This compound is found 

 in black and white pepper. While it is isomeric with morphine, it 

 differs widely from it in all its properties. It can hardly be called 

 an alkaloid, as it has no alkaline reaction, is but feebly basic, and does 

 not show the general alkaloidal reactions. The U. S. P. emphasizes 

 this by giving to piperin the ending in and not ine, which is used for 

 all true alkaloids. It forms colorless or pale yellowish crystals 

 which are, when first put in the mouth, almost tasteless, but produce 

 on prolonged contact a sharp, biting sensation. 



Piperin dissolves in concentrated sulphuric acid with a dark blood- 

 red color, which disappears on dilution with water. Treated with 

 nitric acid it turns rapidly orange, then red. 



Coniine, C 8 H 17 N, occurs in conium maculatum (hemlock), accom- 

 panied by two other alkaloids. It is a colorless, oily liquid, having 

 a disagreeable, penetrating odor. 



Pilocarpine, O U H 16 N 2 O 2 . Found in the leaflets of pilocarpus 

 species. The alkaloid crystallizes with difficulty ; its solutions in 

 ether, alcohol, or water have an alkaline reaction. It is a white, 

 crystalline powder, which dissolves in fuming nitric acid with a 

 faintly greenish tint. The aqueous solution is precipitated by most 

 of the common reagents for alkaloids. The hydrochloride and nitrate 

 are official. 



Nicotine, C 10 H 14 N 2 . Tobacco leaves contain from 2 to 8 per cent, 

 of nicotine, which is a colorless, oily liquid, having a caustic taste 

 and a disagreeable, penetrating odor. It gives with hydrochloric 

 acid a violet, with nitric acid an orange, color. 



Sparteine, C 15 H 26 N 2 . This alkaloid, found in scoparius (broom, 

 Irish broom), is a colorless, oily liquid, turning brown on exposure 

 to air and light. It has a slight aniline-like odor. 



