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Key Documents

M1387

Sigma-Aldrich

4-Methylpyrazole hydrochloride

alcohol dehydrogenase inhibitor

Synonym(s):

Fomepizole

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About This Item

Empirical Formula (Hill Notation):
C4H6N2 · HCl
CAS Number:
Molecular Weight:
118.56
MDL number:
UNSPSC Code:
12352202
PubChem Substance ID:
NACRES:
NA.77

biological source

synthetic (organic)

Quality Level

Assay

≥95%

form

powder

mp

157-159  °C

solubility

methanol: 100 mg/mL, clear, colorless to yellow

storage temp.

2-8°C

SMILES string

Cl.Cc1cn[nH]c1

InChI

1S/C4H6N2.ClH/c1-4-2-5-6-3-4;/h2-3H,1H3,(H,5,6);1H

InChI key

PUCXJHNDMYZOHG-UHFFFAOYSA-N

Gene Information

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Application

4-Methylpyrazole hydrochloride has been used:
  • as a cytochrome P450 2E1 inhibitor
  • as cytochrome P450 2E1 and alcohol dehydrogenase inhibitor in 1C11 neural progenitor cells
  • to inhibit ethanol oxidation in VL-17A cells expressing alcohol dehydrogenase and HepG2 cells

Useful as an antidote in methanol and ethylene glycol poisoning.

Biochem/physiol Actions

4-Methylpyrazole (4MP) inhibits ethanol oxidation in liver microsomes. It also blocks the c-Jun N-terminal kinase (JNK) activation in in vitro liver injury models.
Alcohol dehydrogenase inhibitor

Pictograms

Exclamation mark

Signal Word

Warning

Hazard Statements

Hazard Classifications

Eye Irrit. 2 - Skin Irrit. 2 - STOT SE 3

Target Organs

Respiratory system

Storage Class Code

11 - Combustible Solids

WGK

WGK 3

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

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Kenneth E McMartin et al.
Clinical toxicology (Philadelphia, Pa.), 50(5), 375-383 (2012-05-05)
Fomepizole, a potent inhibitor of alcohol dehydrogenase, has replaced ethanol as antidote for methanol and ethylene glycol intoxications because of a longer duration of action and fewer adverse effects. Prior human studies have indicated that single doses of fomepizole are
Michael Levine et al.
Annals of emergency medicine, 59(6), 527-531 (2012-01-10)
Ethylene glycol remains an important toxic cause of metabolic acidosis and acute renal failure. Traditionally, inhibition of alcohol dehydrogenase along with hemodialysis has been used for treatment. Because of reported long elimination half-life of ethylene glycol during alcohol dehydrogenase inhibition
Chloe C McAlister et al.
Liver transplantation : official publication of the American Association for the Study of Liver Diseases and the International Liver Transplantation Society, 10(2), 315-319 (2004-02-06)
The mechanism by which a liver transplantation might protect a simultaneous kidney transplant in a crossmatch-positive recipient is unknown. Flow cytometry crossmatch (FCXM) has increased the sensitivity of donor-specific antibody (DSA) detection compared with complement-dependant cytotoxicity (CDC). Here we compare
Raido Paasma et al.
Clinical toxicology (Philadelphia, Pa.), 50(9), 823-831 (2012-09-21)
INTRODUCTION. Thorough prognostic and metabolic studies of methanol poisonings are scarce. Our aims were to evaluate the factors associated with sequelae and death from methanol poisoning, to develop a simple risk-assessment chart to evaluate factors associated with sequelae and death
Graham A Tipples et al.
Journal of clinical virology : the official publication of the Pan American Society for Clinical Virology, 30(3), 233-238 (2004-05-12)
Rubella virus generally causes a mild fever, rash illness similar in clinical presentation to infections by other viruses including measles and parvovirus B19. Rubella infections in pregnant women in the first trimester carry a high risk of congenital rubella syndrome

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