acetophenetidin

…major metabolite of acetanilide and phenacetin, which were once commonly used drugs, and it is responsible for their analgesic (pain-relieving) effects. The exact mechanism by which acetaminophen exerts its actions, however, is not fully known. Initially, it was thought that the drug acts primarily by inhibiting cyclooxygenase (COX) enzymes in…

…replaced by the less toxic phenacetin. In 1899 aspirin (acetylsalicylic acid) became the most effective and popular anti-inflammatory, analgesic-antipyretic drug for at least the next 60 years. Cocaine, derived from the coca leaf, was the only known local anesthetic until about 1900, when the synthetic compound benzocaine was introduced. Benzocaine…

…can also be converted to acetophenetidin (also known as phenacetin), an analgesic.