THE PLANT BASES 



159 



Pvridine 



Pyrrole 



Tropane 



Quinoline 



Pyrimidine 



V 



Iminazole 



Purine 



1. The pyridine alkaloids. 



These are, as the name implies, derivatives of pyridine. (Pyridine 

 is a colourless liquid which boils at 115C. It is a strong base and 

 forms salts with acids.) 



CH 



CH CH 



II I 

 CH CH 



N 



Pyridine 



The more important members of this group are: arecoline, coniine, 

 nicotine, piperine and trigonelline. 



Arecoline occurs in the " Betel Nut " which is the fruit of the Areca 

 Palm (Areca Catechu). 



Coniine occurs in all parts of the Hemlock (Conium maculatum), 

 but more especially in the seed. 



Nicotine occurs in the leaves of the Tobacco plant (Nicotiana 

 Tabacum). It is a colourless oily liquid which is intensely poisonous. 

 Its constitution may be represented as : 



CH CH 2 CH 2 



S\ II 



CH C CH CH 2 



I II \/ 

 CH CH N 



\X I 



N CH 3 



It is readily soluble in water and organic solvents. 



