- a white, bitter, slightly water-soluble alkaloid, C20H24N2O2, having needlelike crystals, obtained from cinchona bark: used in medicine chiefly in the treatment of resistant forms of malaria.
- a salt of this alkaloid, especially the sulfate.
- a bitter crystalline alkaloid extracted from cinchona bark, the salts of which are used as a tonic, antipyretic, analgesic, etc, and in malaria therapy. Formula: C 20 H 24 N 2 O 2
