Quinine

C₂₀H₂₄O₂N₂N₂3H₂O. Mp 177°C. An alkaloid of the quinoline group, present in Cinchona bark. It is a diacid base of very bitter taste and alkaline reaction. It crystallizes in prisms or silky needles; the hydrochloride and sulphate are used as a febrifuge but have been largely superseded as a remedy for malaria, although they are still used in the treanment of leg cramps.