AMINES AND AMIDES. CYANOGEN COMPO UNDS. 357 



Amido-acids are acids in which hydrogen has been replaced by 

 NH 2 . Thus, amido-acetic acid, also known as glycocoll or glycine, is 



represented by the formula C 2 H 3 (NH 2 )O 2 or CH 2 / 2 ; it is a sub- 



stance which has both acid and basic properties, and is a product of 

 the decomposition of either glycocholic or hippuric acid by hydro- 

 chloric acid. 



Amido-formic acid or carbamic acid, CH.NH 2 .O 2 , is the acid which, 

 in the form of the ammonium salt, is a constituent of the commercial 

 ammonium carbonate. It is formed by the direct action of carbon 

 dioxide upon ammonia : 



C0 2 + 2NH 3 = C.NH 4 .NH 2 2 . 



Formation of amines and amides. These substances are found 

 as products of animal life (urea), of vegetable life (alkaloids), of 

 destructive distillation (aniline, pyridine), of putrefaction (ptomaines), 

 and may also be produced synthetically for instance, by the action 

 of ammonia upon the chloride or iodide of an alcohol or acid radical : 

 C 2 H 5 .I + NH 3 : HI + NH 2 C 2 H 5 . 



Ethyl iodide. Ammonia. Hydriodic Ethylamine. 

 acid. 



C 2 H 3 O.C1 + 2NH 3 = NH 4 C1 -f NH 2 .C 2 H S O. 



Acetyl Ammonia. Ammonium Acetamide. 



chloride. chloride. 



Amines may also be formed by the action of nascent hydrogen 

 upon the cyanides of the alcoholic radicals : 



CH 3 CN + 4H = NH 2 C 2 H 6 . 

 Methyl cyanide. Ethylamine. 



Amines may in some cases be formed by the action of nascent 

 hydrogen upon mtro-compounds ; the manufacture of aniline depends 

 on this decomposition : 



C 6 H 5 N0 2 + 6H = 2H 2 + NH 2 .C 6 H 5 . 



Nitro-benzene. Hydrogen. Water. Phenylamine, 



or aniline. 



Occurrence of organic bases in nature. The various organic 

 basic substances found in nature are either amines (compounds con- 

 taining carbon, hydrogen, and nitrogen only), or amides (compounds 

 containing, besides the three elements named, also oxygen). But a 

 small number of organic bases is found in the animal system, urea 

 being the most important one. In plants organic bases are more 

 frequently met with, and are grouped together under the name of 

 alkaloids. While the constitution of many alkaloids has not yet 

 been sufficiently explained, we know that many of them are deriv- 



