CHEMISTRY OF THE PTOMAIjSTES. 199 



It forms two compounds with mercuric chloride. (CgHjj 

 N.HCl)2HgCl2 crystallizes in small white needles, which 

 are slightly soluble in water and in dilute alcohol, insoluble 

 in absolute alcohol, and on exposure to moist air undergo 

 change. The second compound, 2(CjHjiN.HCl).3HgCl2, is 

 obtained by adding an excess of concentrated mercuric 

 chloride to a concentrated solution of the hydrochloride. 

 It forms slightly yellow, somewhat longer needles which 

 are insoluble in the principal solvents, and are likewise 

 changed by atmospheric humidity. 



The loDOMETHYLATE, OgHnN.CHjI, is formed by 

 mixing solutions of the base and methyl iodide in absolute 

 ether. It is deposited as a network of fine white needles, 

 which are but slowly altered in the air, and are soluble in 

 absolute alcohol. This solution on the addition of a little 

 potash assumes a dark-red color, which is heightened by 

 the addition of a little hydrochloric or acetic acid, and 

 destroyed by ammonia without any resultant fluorescence. 

 Warmed with excess of moist solid potash it becomes 

 garnet-red in color and gives off an odor resembling that 

 of the dihydropyridines. It thus behaves the same as the 

 pyridine iodomethylates. 



On oxidation with potassium permanganate it yields an 

 acid which melts at 229°-230°, and begins to sublime at 

 150°. It presents all the characteristics of nicotinic acid, 

 CjHjNOj, which is formed as the result of oxidation of 

 nicotine. With hydrochloric acid it forms the compound, 

 C5H5NO2.HCI. With copper acetate it forms a salt ; this, 

 distilled with lime, yields a substance which on boiling 

 with platinum chloride and water forms the compound 

 (05115X01)2. PtClj. This same substance forms an iodo- 

 methylate, which in alcoholic solution gives, on addition of 

 potash, the characteristic reaction of pyridine bases. 



The base, CjHuIsr, therefore yields pyridine and nico- 

 tinic acid. 



A Base, O8H13N, was obtained by Gautier and Etard 

 (1881) from the ehloroformic extracts (see rae'thod, page 164) 

 from putrefying mackerel, as well as from the decomposing 



