Acetaminophen: How much do you really know about it?
acetaminophen is very popular and is regularly used as a non-prescription drug to relieve pain caused by a wide variety of symptoms such as headaches, muscle and joint pains, or menstrual cramps. 1
Discovery and History
Papa-aminophenol was discovered in the late 1800’s and is a parent compound of acetaminophen and acetophenetidin.1 It was discovered that papa-aminophenol could reduce fever, however it was highly toxic. 1 It was discovered shortly after that acetophenetidin was much less toxic and was safe to be used medically. 1 It was also found to be antipyretic (fever-reducing) and was also a good pain-reliever so it became a popular medicinal drug to relieve both fever and pain. In 1949 it was discovered that the body converts acetophenetidin into an even less toxic substance called acetaminophen. 1 After this discovery, acetaminophen began to replace the now popular acetophenetidin as an analgesic (painkiller).1
The chemical formula of the acetaminophen molecule is C8H9NO2.2 Its IUPAC name is N-(4-hydroxyphenyl)acetamide.2 Acetaminophen contains a benzene ring core, with a hydroxyl group and an amide group attached in the para pattern.3 The amide group is ethanamide and is attached to the benzene ring by the nitrogen atom. 3 The carbon atoms of the benzene ring all have atoms bonded in the same plane at about 120 degrees from each other.4 This VSEPR shape is known as trigonal planar. 4 The hydroxyl group has a bent tetrahedral shape because of the two lone pairs on the oxygen atom. 4 The nitrogen atom that attaches the benzene ring to the amide group has a tetrahedral shape, but since there is a lone pair present, the attached atoms form a trigonal pyramidal shape.4 The carbon at the end of the amide group has a tetrahedral shape with a hydrogen bonded at each site.4 The carbon in the middle of the amide group has a single bond between the nitrogen atom and the other...