184 Gerhardfs Organic Chemistry. 



at least the four first named, are very poisonous. The second 

 class includes those which contain oxygen ; these are all solid 

 and crystal lizable, and with but a few exceptions, obtained from 

 plants, of which they constitute the active principles. Urea is 

 the only alkaloid which is found in the animal organism, and the 

 only natural one which we have been able to reproduce artificially. 

 The action of ammonia upon oil of mustard and of sulphuretted 

 and seleniuretted hydrogen and ammonia upon aldehyde, afford 

 alkaloids in which sulphur and selenium replace oxygen. Alkar- 

 sine is one in which acesenic replaces nitrogen. 



M. Hoffmann, in his late beautiful researches, has discovered 

 several new alkaloids derived from anilene C 6 H 7 N, by a replace- 

 ment of its hydrogen. Chlorainline and bichlorainlene corres- 

 pond to anilene in which one or two equivalents of hydrogen 

 have been replaced by chlorine, and two corresponding species 

 are obtained which contain bromine. In nitranilene we have a 

 beautiful instance of substitution by the residue of nitric acid. 

 It is anilene in which NH0 3 —Ore places H , and is represented 

 by C, (H 5 NHOJN; although it contains the elements of a 

 powerful acid its neutralizing power is the same as anilene itself. 



The researches of M. Gerhardt have shown that the alkaloids, 

 like ammonia, act by their hydrogen upon oxydized bodies to 

 form compounds which correspond precisely to the amides. The 

 oxalate of anilene when decomposed by heat loses two equiva- 

 lents of water, and forms oxanilide, which, like oxamide, regen- 

 erates oxalic acid and the alkaloids by the influence of acids or 

 alkalies. The anilide of formic acid has also been obtained, and 

 salphanilic acid which is monobasic, and corresponds to the ox- 

 amic. The oxaluric acid is a coupled acid in which urea sus- 

 tains the same relation as ammonia in the oxamic ; in its decom- 

 position it assumes the elements of water and regenerates oxalic 

 acid and urea. 



The artificial alkaloids are formed by a great variety of p r(> 

 cesses. The action of fused hydrate of potash upon indigo °J 

 isatine results in the abstraction of its oxygen and a portion oi 

 carbon, which is oxydized at trie expense of the water, and fortn s 

 carbonate of potash, while anilene and hydrogen gas are evolved. 

 The oxygenized alkaloids, quinine, cinchonine, and strychnine, 

 by the same process afford quinoleine. The action of i3PSC eD 

 hydrogen upon the nitric species of hydro-carbons has furnish^ 

 many new alkaloids. When a solution of nitro-benz ene 

 C 6 H s N0 2 is mixed with dilute sulphuric acid and zinc, tne 

 liberated hydrogen combines with it and forms anilene with W 

 liberation of two equivalents of water C 6 H 5 K0 2 +6"^ 

 C 5 H ? N + 2H 9 O. The same result is obtained by th action 

 of sulphuretted hydrogen, the sulphur separating. It is fr^ 

 decomposition of binitric benzene that nitraniline is obtained. 



