2-thiouracil

Structural formula
General
Non-proprietary name	Thiouracil
other names	2-thioxo-2,3-dihydro-1 H -pyrimidin-4-one
Molecular formula	C 4 H 4 N 2 OS
Brief description	bitter tasting crystals
External identifiers / databases
EC number	205-508-8
ECHA InfoCard	100.005.008
PubChem	1269845
ChemSpider	1066108
Wikidata	Q20892027
Drug information
ATC code	H03 BA
Drug class	Anti-thyroid drug
Mechanism of action	Iodization inhibitor
properties
Molar mass	128.15 g mol −1
Melting point	> 300 ° C (decomposition)
solubility	almost insoluble in ethanol , diethyl ether and acids; soluble in alkali solutions;
safety instructions
	Please note the exemption from the labeling requirement for drugs, medical devices, cosmetics, food and animal feed
GHS labeling of hazardous substances Caution
H and P phrases	H: 351
	P: 281
Toxicological data	2850 mg kg −1 ( LD 50 , mouse , oral )
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

2-Thiouracil is a historically relevant anti -thyroid drug from the group of thionamides . The Graves' disease in 1943 pioneered by Edwin B. Astwood treated by this Thyreostatikums.

Mechanism of action and side effects

It prevents the binding of iodine and thus the formation of thyroid hormones ( triiodothyronine and thyroxine ). Its mechanism of action corresponds to that of the successor products still used today (e.g. carbimazole and thiamazole ).

Side effects of overdose are the risk of hypothyroidism and the like. cancer triggering especially in the thyroid and liver . The drug is contraindicated during breastfeeding, as it accumulates in breast milk and can endanger the child.

chemistry

Thiouracil belongs to the group of heterocycles and is a derivative of thiourea .

synthesis

The conversion of thiourea and formylacetic acid yields thiouracil with elimination of water .

Tautomerism

The thione form and the thiol form of thiouracil are subject to tautomerism :

Individual evidence

↑ ^a ^b ^c Entry on 2-thiouracil. In: Römpp Online . Georg Thieme Verlag, accessed on September 30, 2014.
↑ ^a ^b Entry on 2-thiouracil in the ChemIDplus database of the United States National Library of Medicine (NLM) .
↑ ^a ^b Data sheet 2-Thiouracil from Sigma-Aldrich , accessed on March 6, 2014 ( PDF ).
^ Werner E. Gerabek : Encyclopedia Medical History. Walter de Gruyter, 2005, ISBN 978-3-11-015714-7 , p. 152 ( limited preview in the Google book search).
↑ Thiouracil . Roche Lexicon; accessed on March 6, 2014.
↑ G. Kuschinsky: Short textbook of pharmacology . ISBN 3-13-368509-0 , p. 273.
^ Joachim W. Dudenhausen: gynecology and obstetrics. Walter de Gruyter, 2003, ISBN 978-3-11-016562-3 , p. 305 ( limited preview in the Google book search).
^ Hans Beyer and Wolfgang Walter : Organische Chemie , S. Hirzel Verlag, Stuttgart, 1984, p. 749, ISBN 3-7776-0406-2 .

[RÖMPP_Online-1] Entry on 2-thiouracil. In: Römpp Online . Georg Thieme Verlag, accessed on September 30, 2014.

[ChemIDplus-2] Entry on 2-thiouracil in the ChemIDplus database of the United States National Library of Medicine (NLM) .

[Sigma-3] Data sheet 2-Thiouracil from Sigma-Aldrich , accessed on March 6, 2014 ( PDF ).

[4] Werner E. Gerabek : Encyclopedia Medical History. Walter de Gruyter, 2005, ISBN 978-3-11-015714-7 , p. 152 ( limited preview in the Google book search).

[5] Thiouracil . Roche Lexicon; accessed on March 6, 2014.

[6] G. Kuschinsky: Short textbook of pharmacology . ISBN 3-13-368509-0 , p. 273.

[7] Joachim W. Dudenhausen: gynecology and obstetrics. Walter de Gruyter, 2003, ISBN 978-3-11-016562-3 , p. 305 ( limited preview in the Google book search).

[Beyer-8] Hans Beyer and Wolfgang Walter : Organische Chemie , S. Hirzel Verlag, Stuttgart, 1984, p. 749, ISBN 3-7776-0406-2 .