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Substance Name: Levothyroxine [INN:BAN]
RN: 51-48-9
UNII: Q51BO43MG4
InChIKey: XUIIKFGFIJCVMT-LBPRGKRZSA-N

Notes

  • The major hormone derived from the thyroid gland. Thyroxine is synthesized via the iodination of tyrosines ( MONOIODOTYROSINE) and the coupling of iodotyrosines ( DIIODOTYROSINE) in the THYROGLOBULIN. Thyroxine is released from thyroglobulin by proteolysis and secreted into the blood. Thyroxine is peripherally deiodinated to form TRIIODOTHYRONINE which exerts a broad spectrum of stimulatory effects on cell metabolism. /Thyroxine/
  • The major hormone derived from the thyroid gland. Thyroxine is synthesized via the iodination of tyrosines (MONOIODOTYROSINE) and the coupling of iodotyrosines (DIIODOTYROSINE) in the THYROGLOBULIN. Thyroxine is released from thyroglobulin by proteolysis and secreted into the blood. Thyroxine is peripherally deiodinated to form TRIIODOTHYRONINE which exerts a broad spectrum of stimulatory effects on cell metabolism.

Molecular Formula

  • C15-H11-I4-N-O4

Molecular Weight

  • 776.855
 

Classification Codes

  • Hormone
  • Human Data
  • Mutation Data
  • Reproductive Effect

Names and Synonyms

Name of Substance

  • Levothyroxine [INN:BAN]

MeSH Heading

  • Thyroxine

Synonyms

  • (-)-Thyroxine
  • 3,3',5,5'-Tetraiodo-L-thyronine
  • 3,5,3',5'-Tetraiodo-L-thyronine
  • 3,5,3',5'-Tetraiodothyronine
  • 3-(4-(4-Hydroxy-3,5-diiodophenoxy)-3,5-diiodophenyl)alanine
  • 4-14-00-02373 (Beilstein Handbook Reference)
  • beta-((3,5-Diiodo-4-hydroxyphenoxy)-3,5-diiodophenyl)alanine
  • BRN 2228515
  • CCRIS 6739
  • EINECS 200-101-1
  • HSDB 3108
  • L-3,5,3',5'-Tetraiodothyronine
  • L-T4
  • L-Thyroxin
  • L-Thyroxine
  • L-Tyrosine, O-(4-hydroxy-3,5-diiodophenyl)-3,5-diiodo-
  • Laevothyroxinum (acid)
  • Levothyroxine
  • Levothyroxinum (acid)
  • NSC 36397
  • O-(4-Hydroxy-3,5-diiodophenyl)-3,5-diiodotyrosine
  • Synthroid
  • T4
  • T4 (Hormone)
  • Tetraiodothyronine
  • Thryroxine, l-
  • THX
  • Thyratabs
  • Thyrax
  • Thyreoideum
  • Thyroxin
  • Thyroxinal
  • Thyroxine
  • Thyroxine (l)
  • Thyroxine (VAN)
  • Thyroxine iodine
  • UNII-Q51BO43MG4

Systematic Names

  • L-Tyrosine, O-(4-hydroxy-3,5-diiodophenyl)-3,5-diiodo-
  • Thyroxine
  • Thyroxine, L- (8CI)

Mixture Names

  • Armour Thyroid
  • Eutirox
  • Guna-lympho

Registry Numbers

CAS Registry Number

  • 51-48-9

FDA UNII

  • Q51BO43MG4

Other Registry Numbers

  • 1373931-44-2
  • 587-29-1
  • 587-30-4
  • 7200-84-2
  • 74-16-8
  • 7488-70-2

System Generated Number

  • 0000051489

Structure Descriptors

InChI

1S/C15H11I4NO4/c16-8-4-7(5-9(17)13(8)21)24-14-10(18)1-6(2-11(14)19)3-12(20)15(22)23/h1-2,4-5,12,21H,3,20H2,(H,22,23)/t12-/m0/s1

InChIKey

XUIIKFGFIJCVMT-LBPRGKRZSA-N

Smiles

c1(Oc2c(cc(C[C@@H](C(O)=O)N)cc2I)I)cc(c(O)c(c1)I)I

Toxicity

Organism Test Type Route Reported Dose (Normalized Dose) Effect Source
child TDLo oral 328ug/kg (0.328mg/kg) VASCULAR: BP LOWERING NOT CHARACTERIZED IN AUTONOMIC SECTION

CARDIAC: PULSE RATE INCREASE WITHOUT FALL IN BP		 Pediatrics. Vol. 73, Pg. 313, 1984.
child TDLo oral 485ug/kg (0.485mg/kg) ENDOCRINE: EVIDENCE OF THYROID HYPERFUNCTION

CARDIAC: ARRHYTHMIAS (INCLUDING CHANGES IN CONDUCTION)		 European Journal of Pediatrics. Vol. 150, Pg. 217, 1991.
man TDLo oral 30ug/kg/3W-I (0.03mg/kg) CARDIAC: EKG CHANGES NOT DIAGNOSTIC OF ABOVE British Medical Journal. Vol. 292, Pg. 1185, 1986.
man TDLo oral 63ug/kg (0.063mg/kg) CARDIAC: PULSE RATE INCREASE WITHOUT FALL IN BP

BEHAVIORAL: "HALLUCINATIONS, DISTORTED PERCEPTIONS"		 Journal of Toxicology, Clinical Toxicology. Vol. 20, Pg. 517, 1983.
man TDLo oral 10286ug/kg (10.286mg/kg) BEHAVIORAL: EXCITEMENT

CARDIAC: PULSE RATE INCREASE WITHOUT FALL IN BP

GASTROINTESTINAL: NAUSEA OR VOMITING		 Veterinary and Human Toxicology. Vol. 41, Pg. 323, 1999.
women TDLo oral 42ug/kg/1W-I (0.042mg/kg) BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD Neurology. Vol. 35, Pg. 1792, 1985.
women TDLo oral 400ug/kg/2D-I (0.4mg/kg) BEHAVIORAL: COMA

CARDIAC: ARRHYTHMIAS (INCLUDING CHANGES IN CONDUCTION)		 Intensive Care Medicine. Vol. 13, Pg. 33, 1987.

Physical Properties

Physical Property Value Units Temp (deg C) Source
Melting Point 235.5 deg C   EXP
log P (octanol-water) 4.120 (none)   EST
Water Solubility 1.05E-04 mg/L 25 EST
Vapor Pressure 1.24E-17 mm Hg 25 EST
Henry's Law Constant 7.91E-19 atm-m3/mole 25 EST
Atmospheric OH Rate Constant 4.17E-11 cm3/molecule-sec 25 EST

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