A series of [(heteroarylamino) phenyl] alkanoic acids having pyridine, quinoline, or pyrimidine as the heteroaryl moiety was prepared as potential antiinflammatory agents. Among them, 2-[4-(2-pyridylamino) phenyl] propionic acid (14b) showed excellent antiinflammatory and analgesic activities with less tendency to cause gastric side effects. Structure-activity relationships are discussed.