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Substance Name: Methimazole [USP]
RN: 60-56-0
UNII: 554Z48XN5E
InChIKey: PMRYVIKBURPHAH-UHFFFAOYSA-N

Note

  • A thioureylene antithyroid agent that inhibits the formation of thyroid hormones by interfering with the incorporation of iodine into tyrosyl residues of thyroglobulin. This is done by interfering with the oxidation of iodide ion and iodotyrosyl groups through inhibition of the peroxidase enzyme.

Molecular Formula

  • C4-H6-N2-S

Molecular Weight

  • 114.1714
 

Classification Codes

  • Antithyroid Agents
  • Drug / Therapeutic Agent
  • Hormone Antagonists
  • Hormones, Hormone Substitutes, and Hormone Antagonists
  • Human Data
  • Mutation Data
  • Reproductive Effect
  • Thyroid Inhibitor
  • Tumor Data

Names and Synonyms

Name of Substance

  • Methimazole
  • Methimazole [USP]
  • Thiamazole [INN]

MeSH Heading

  • Methimazole

Synonyms

  • 1,3-Dihydro-1-methyl-2H-imidazole-2-thione
  • 1-Methyl-1,3-dihydroimidazole-2-thione
  • 1-Methyl-2-mercaptoimidazole
  • 1-Methylimidazole-2(3H)-thione
  • 1-Methylimidazole-2-thiol
  • 1-Metylo 2 merkaptoimidazolem
  • 1-Metylo 2 merkaptoimidazolem [Polish]
  • 2-Mercapto-1-methylimidazole
  • 2-Mercaptomethylimidazole
  • 2H-Imidazole-2-thione, 1,3-dihydro-1-methyl-
  • 4-Imidazoline-2-thione, 1-methyl-
  • AI3-60285
  • Basolan
  • Danantizol
  • EINECS 200-482-4
  • Favistan
  • Felimazole
  • Frentirox
  • HSDB 3361
  • Mercaptazole
  • Mercazole
  • Mercazolyl
  • Mercazolylum
  • Merkastan
  • Merkazolil
  • Metazolo
  • Methimazol
  • Methimazole
  • Methimazolum
  • Methylmercaptoimidazole
  • Metimazol
  • Metizol
  • Metothyrin
  • Metothyrine
  • Metotirin
  • N-Methyl-2-mercaptoimidazole
  • NSC 38608
  • Strumazol
  • Tapazole
  • Thacapzol
  • Thiamazol
  • Thiamazol [INN-French]
  • Thiamazole
  • Thiamazolum
  • Thiamazolum [INN-Latin]
  • Thycapsol
  • Thycapzol
  • Thymidazol
  • Thymidazole
  • Tiamazol
  • Tiamazol [INN-Spanish]
  • Tiamazolo
  • Tiamazolo [DCIT]
  • UNII-554Z48XN5E
  • USAF EL-30

Systematic Names

  • 2H-Imidazole-2-thione, 1,3-dihydro-1-methyl-
  • Imidazole-2-thiol, 1-methyl-
  • Thiamazole

Superlist Name

  • Methimazole

Registry Numbers

CAS Registry Number

  • 60-56-0

FDA UNII

  • 554Z48XN5E

Other Registry Numbers

  • 4708-61-6
  • 85916-84-3

System Generated Number

  • 0000060560

Structure Descriptors

InChI

1S/C4H6N2S/c1-6-3-2-5-4(6)7/h2-3H,1H3,(H,5,7)

InChIKey

PMRYVIKBURPHAH-UHFFFAOYSA-N

Smiles

c1(=S)n(cc[nH]1)C

Toxicity

Organism Test Type Route Reported Dose (Normalized Dose) Effect Source
mouse LD50 intraperitoneal 500mg/kg (500mg/kg)   National Technical Information Service. Vol. AD277-689,
mouse LD50 oral 860mg/kg (860mg/kg) PERIPHERAL NERVE AND SENSATION: SPASTIC PARALYSIS WITH OR WITHOUT SENSORY CHANGE

BEHAVIORAL: TREMOR

BEHAVIORAL: SOMNOLENCE (GENERAL DEPRESSED ACTIVITY)		 Arzneimittel-Forschung. Drug Research. Vol. 4, Pg. 20, 1954.
mouse LD50 subcutaneous 345mg/kg (345mg/kg) BEHAVIORAL: TREMOR

BEHAVIORAL: SOMNOLENCE (GENERAL DEPRESSED ACTIVITY)

PERIPHERAL NERVE AND SENSATION: SPASTIC PARALYSIS WITH OR WITHOUT SENSORY CHANGE		 Arzneimittel-Forschung. Drug Research. Vol. 4, Pg. 20, 1954.
rat LD50 oral 2250mg/kg (2250mg/kg) BEHAVIORAL: SOMNOLENCE (GENERAL DEPRESSED ACTIVITY)

PERIPHERAL NERVE AND SENSATION: SPASTIC PARALYSIS WITH OR WITHOUT SENSORY CHANGE

BEHAVIORAL: TREMOR		 Arzneimittel-Forschung. Drug Research. Vol. 4, Pg. 20, 1954.
rat LD50 subcutaneous 1050mg/kg (1050mg/kg)   Farmaco, Edizione Scientifica. Vol. 14, Pg. 54, 1959.
women TDLo oral 13mg/kg/33D-I (13mg/kg) GASTROINTESTINAL: OTHER CHANGES

BEHAVIORAL: EXCITEMENT

SENSE ORGANS AND SPECIAL SENSES: OTHER: EAR		 Clinical Endocrinology Vol. 51, Pg. 667, 1999.
women TDLo oral 492mg/kg/88W- (492mg/kg) BLOOD: AGRANULOCYTOSIS

ENDOCRINE: CHANGE IN GONADOTROPINS		 Netherlands Journal of Medicine. Vol. 43, Pg. 71, 1993.

Physical Properties

Physical Property Value Units Temp (deg C) Source
Melting Point 146 deg C   EXP
Boiling Point 280 deg C   EXP
log P (octanol-water) -0.34 (none)   EXP
Water Solubility 2.75E+05 mg/L 25 EST
Vapor Pressure 3.28E-04 mm Hg 25 EST
Henry's Law Constant 2.03E-06 atm-m3/mole 25 EST
Atmospheric OH Rate Constant 1.51E-10 cm3/molecule-sec 25 EST

Physical property data is provided to ChemIDplus by SRC, Inc.