Note:  Do not rely on this information. It is very old.


Cinchonine, an alkaloid occurring with quinine and other closely related substances, in cinchona bark. Its chemical composition is represented by the formula C19H22N2O, and its constitution has been the subject of much research and speculation, but is not yet established. It crystallises in monoclinic prisms, melting at about 250° C, and in its physiological action resembles quinine, but is less marked.