BETAINES 151 



Hypaphorine or Trigonelline or 



Tryptophan-betaine. Nicotinic acid-betaine. 



-CH 2 -CH-N(OH 3 ) 3 

 CO-0 



The betaines can be prepared by the methylation of the amino acids with 

 methyl iodide and alkali but are usually obtained by separation from the 

 natural sources. 



They are colourless crystalline solids and have a feebly basic character 

 forming salts with mineral acids, e.g. betaine hydrochloride, and double salts 

 with salts of the heavy metals. 



A full account of these compounds is given in Barger's " The Simpler 

 Natural Bases ". 



