The presence of cinchonine may also be positively determined by reference to the behaviour of that alkaloid.
Red bark contains not only quinine and cinchonine, but also cinchonidine.
When cinchonine is distilled with solid potassium hydrate, it yields pyrrol and bases of both the pyridine and quinoline series.
Cinchonidine, when heated with potassium hydrate, yields quinoline also, and with nitric acid the same products as cinchonine.
Dr de Vrij states that the substance known under this name is a mixture of hydrochlorate of cinchonidine and of cinchonine.
cinchonine may be prepared from its sulphate or disulphate in the same way as quinine.
If this be quinidine, it will be dissolved on the addition of proportionately more ether, while cinchonine will remain unaffected.
The operation is then repeated, the ether being replaced by chloroform in which both quinine and cinchonine are soluble.
cinchonine cin·cho·nine (sĭng'kə-nēn', sĭn'chə-)
An alkaloid derived from the bark of various cinchona trees and used as an antimalarial agent.