Paracetamol (C8H9NO2) Structure, Properties and Nomenclature


Explore Paracetamol (C8H9NO2), a widely used analgesic and antipyretic. Learn its structure, key properties, IUPAC name, synonyms, and its effectiveness in relieving pain and reducing fever with fewer side effects than aspirin.

What is Paracetamol (C8H9NO2)?

Paracetamol, also known as acetaminophen in North America, is a widely used medication for pain relief and fever reduction. It is classified as an analgesic and antipyretic. Unlike nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or aspirin, paracetamol has minimal anti-inflammatory effects. Its exact mechanism of action is not fully understood but is thought to involve the inhibition of cyclooxygenase (COX) enzymes in the central nervous system, which reduces the production of prostaglandins that sensitize pain receptors and mediate fever. It is a common ingredient in over-the-counter cold and flu remedies, pain relievers, and fever reducers.

Properties of Paracetamol (C8H9NO2)


Property Value
Molecular Formula C₈H₉NO₂
Molecular Weight 151.16 g/mol
Density 1.26 g/cm³
Boiling Point Decomposes at 300 °C
Melting Point 169–171 °C
Hybridization Aromatic carbons are sp² hybridized;
the amide nitrogen is sp² hybridized;
the carbon of the methyl group is sp³ hybridized.
Appearance White crystalline powder
Solubility Slightly soluble in water;
soluble in ethanol and hot water.

Nomenclature of Paracetamol

  • Common name: Paracetamol, Acetaminophen
  • IUPAC name: N-(4-hydroxyphenyl)ethanamide

Synonyms

  • Acetaminophen
  • 4-Hydroxyacetanilide
  • N-Acetyl-p-aminophenol
  • 4-Acetamidophenol
  • APAP
  • Tylenol

MH. JIM

MH. JIM

Independent science writer passionate about chemistry. Through UR Gate, I simplify chemical topics for researchers and enthusiasts while providing reliable resources for students and scientists worldwide.