NAPQI

NAPQI
Clinical data
Other names	N-Acetyl-p-benzoquinone imine; N-Acetylimidoquinone
Identifiers
	IUPAC name N-(4-Oxo-1-cyclohexa-2,5-dienylidene)acetamide;
CAS Number	50700-49-7 ;
PubChem CID	39763;
IUPHAR/BPS	6299;
ChemSpider	36356 ;
UNII	G6S9BN13TI;
ChEBI	CHEBI:29132 ;
ChEMBL	ChEMBL33232 ;
CompTox Dashboard (EPA)	DTXSID20198756 ;
ECHA InfoCard	100.168.312
Chemical and physical data
Formula	C8H7NO2
Molar mass	149.149 g·mol−1
3D model (JSmol)	Interactive image;
	SMILES CC(=O)N=c1ccc(=O)cc1;
	InChI InChI=1S/C8H7NO2/c1-6(10)9-7-2-4-8(11)5-3-7/h2-5H,1H3 ; Key:URNSECGXFRDEDC-UHFFFAOYSA-N ;
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NAPQI, also known as NAPBQI or N-acetyl-p-benzoquinone imine, is a toxic byproduct produced during the xenobiotic metabolism of the analgesic paracetamol (acetaminophen).^[1] It is normally produced only in small amounts, and then almost immediately detoxified in the liver.

However, under some conditions in which NAPQI is not effectively detoxified (usually in the case of paracetamol overdose), it causes severe damage to the liver. This becomes apparent 3–4 days after ingestion and may result in death from fulminant liver failure several days after the overdose.

^ Mehta S (25 August 2012). "Metabolism of Paracetamol (Acetaminophen), Acetanilide and Phenacetin | Medicinal Chemistry | PharmaXChange.info". pharmaxchange.info. Archived from the original on 11 May 2022. Retrieved 29 August 2012.

[met1-1] Mehta S (25 August 2012). "Metabolism of Paracetamol (Acetaminophen), Acetanilide and Phenacetin | Medicinal Chemistry | PharmaXChange.info". pharmaxchange.info. Archived from the original on 11 May 2022. Retrieved 29 August 2012.

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