Quinine

Quinine ( /ˈkwaɪnaɪn/, /ˈkwɪniːn/ or /kwɪˈniːn/ KWIN-een) is a natural white crystalline alkaloid having antipyretic (fever-reducing), antimalarial, analgesic (painkilling), and anti-inflammatory properties and a bitter taste. It is a stereoisomer of quinidine which, unlike quinine, is an antiarrhythmic. Quinine contains two major fused-ring systems: the aromatic quinoline and the bicyclic quinuclidine.