Dimercaprol

Structural formula
1: 1 mixture of ( R ) -form (left) and ( S ) -form (right)
General
Non-proprietary name	Dimercaprol
other names	( RS ) -2,3-dimercapto-1-propanol ( RS ) -2,3-dimercaptopropan-1-ol ( RS ) -dithioglycerin British Anti-Lewisite BAL
Molecular formula	C 3 H 8 OS 2
Brief description	yellow liquid with a characteristic odor
External identifiers / databases
CAS number 59-52-9 (racemate) EC number 200-433-7 ECHA InfoCard 100,000,394 PubChem 3080 ChemSpider 2971 DrugBank DB06782 Wikidata Q413968
Drug information
ATC code	V03 AB09
properties
Molar mass	124.22 g · mol -1
Physical state	liquid
density	1.25 g cm −3
boiling point	140 ° C (at 54 hPa)
Vapor pressure	7.4 h Pa (100 ° C)
solubility	moderate in water (87 g l −1 at 20 ° C)
Refractive index	1.5749 (20 ° C)
safety instructions
Please note the exemption from the labeling requirement for drugs, medical devices, cosmetics, food and animal feed GHS labeling of hazardous substances danger H and P phrases H: 301-315-319-335 P: 261-301 + 310-305 + 351 + 338
Toxicological data	217 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 . Refractive index: Na-D line , 20 ° C

Dimercaprol or Dimercaptopropanol is a substance derived from glycerine , which is one of the alcohols as well as one of their sulfur analogues , the thiols . It is used as an antidote for poisoning with various heavy metals .

History and use

Dimercaprol was developed by British biochemists at Oxford University during World War II as an antidote to the warfare agent lewisite . This led to the name British Anti-Lewisite ( BAL for short ). In Germany, BAL was on the market as a sulfactin .

Dimercaprol was indicated as a medicinal substance for poisoning with arsenic , mercury , lead and gold salts, but has been replaced by DMPS , which is better tolerated with the same effectiveness. There is little experience with the treatment of poisoning with antimony , bismuth , chromium , copper and nickel ; The substance is not suitable for the treatment of poisoning with cadmium , iron and selenium salts, since the complex compounds formed are even more toxic than the metal ions themselves. The treatment of Wilson's disease with dimercaprol is obsolete.

Dimercaprol is injected intramuscularly every 4–6 hours as an oily solution based on peanut oil . Therefore, it is contraindicated in peanut allergy .

Adverse effects occur from 4 mg / kg body weight in 14% of the patients, from 5 mg / kg body weight in 65%. In addition to pain at the injection site, purulent abscesses may appear there. A high fever of up to 40 ° C can develop particularly in children. About 10-30 minutes after an injection, you may experience a tight chest without cardiac symptoms, combined with anxiety , high blood pressure and a racing heart , which will subside within an hour.

Alternatives are dimercaptopropane sulfonic acid (DMPS) and dimercaptosuccinic acid (DMSA).

Manufacturing

The addition of bromine to the carbon-carbon double bond of allyl alcohol yields racemic 2,3-dibromo-1-propanol. When reacted with sodium hydrogen sulfide , the two bromine atoms are substituted by mercapto radicals and dimercaprol is formed.

Properties and effects

Dimercaprol is a yellowish liquid with a characteristic odor of mercaptan. It dissolves moderately well in water and is flammable, but difficult to ignite due to its high flash point of 112 ° C. The antidote effect of dimercaprol is based on the reactivation of thiol groups in proteins (especially enzymes ) blocked by heavy metals through chelation with the metal ions via the thiol groups of dimercaprol.

Isomerism

Dimercaprol has a stereocenter , so it is chiral . There is an ( R ) isomer and an ( S ) isomer. Dimercaprol is used as a racemate [1: 1 mixture of the ( R ) isomer and the ( S ) isomer]. The chirality is insignificant for use as a heavy metal antidote.

Individual evidence

1. ↑ ^{a b c d e f g h} Entry on dimercaprol in the GESTIS substance database of the IFA , accessed on January 8, 2018(JavaScript required) .
2. ↑ David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Physical Constants of Organic Compounds, pp. 3-186.
3. ↑ Entry on dimercaprol in the ChemIDplus database of the United States National Library of Medicine (NLM) .
4. ^ Helmut Schubothe: Arsenic poisoning. In: Ludwig Heilmeyer (ed.): Textbook of internal medicine. Springer-Verlag, Berlin / Göttingen / Heidelberg 1955; 2nd edition ibid. 1961, pp. 1203-1205, in particular pp. 1204 f.
5. ↑ ^{a b} K. Hardtke et al. (Ed.): Commentary on the European Pharmacopoeia Ph. Eur. 4.0, Dimercaprol. Loose-leaf collection, 19th delivery 2005, Wissenschaftliche Verlagsgesellschaft Stuttgart.
6. ^ German Society for Neurology: Guideline Morbus Wilson .
7. ↑ Wendy Macías Konstantopoulos, Michele Burns Ewald, Daniel S. Pratt: Case 22-2012: A 34-Year-Old Man with Intractable Vomiting after Ingestion of an Unknown Substance . In: New England Journal of Medicine 2012; 367: 259-268.
8. ^ Axel Kleemann , Jürgen Engel, Bernd Kutscher and Dieter Reichert: Pharmaceutical Substances , 4th edition (2000), 2 volumes published by Thieme-Verlag Stuttgart, pp. 662-663, ISBN 978-1-58890-031-9 ; online since 2003 with biannual additions and updates.
9. ↑ European Pharmacopoeia, Deutscher Apotheker Verlag Stuttgart, 6th edition, 2008, pp. 2339-2340, ISBN 978-3-7692-3962-1 .

This article is about a health issue. It is not used for self-diagnosis and does not replace a diagnosis by a doctor. Please note the information on health issues !