Dimercaprol

Dimercaprol

Names
IUPAC name 2,3-bis(sulfanyl)propan-1-ol
Other names 2,3-dimercaptopropanol British anti-Lewisite
Identifiers
CAS Number	59-52-9 Y 16495-08-2 (2R)-2-sulfanyl Y 16495-16-2 (2S)-2-sulfanyl Y
Beilstein Reference	1732058
ChEMBL	ChEMBL1597 Y
ChemSpider	2971 Y 5342114 (2R)-2-sulfanyl Y 2496803 (2S)-2-sulfanyl Y
DrugBank	DB06782 Y
EC Number	200-433-7
Jmol 3D model	Interactive image
KEGG	D00167 Y
MeSH	Dimercaprol
PubChem	3080 6971262 (2R)-2-sulfanyl 3246063 (2S)-2-sulfanyl
RTECS number	UB2625000
UNII	0CPP32S55X Y
UN number	2810
InChI InChI=1S/C3H8OS2/c4-1-3(6)2-5/h3-6H,1-2H2 Y Key: WQABCVAJNWAXTE-UHFFFAOYSA-N Y
SMILES OCC(S)CS
Properties
Chemical formula	C 3H 8S 2O
Molar mass	124.225 g mol−1
Density	1.239 g cm−3
Boiling point	120 °C; 248 °F; 393 K at 2.0 kPa
log P	0.627
Acidity (pKa)	8.999
Basicity (pKb)	4.998
Refractive index (nD)	1.573
Pharmacology
ATC code	V03AB09
Vapor pressure	{{{value}}}
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Dimercaprol (INN), also called British anti-Lewisite or British antilewisite (abbreviated BAL), is a medication for chelation therapy in metal toxicity, including heavy metal poisoning. Dimercaprol is used medically in the treatment of toxic metal poisoning by arsenic, mercury, gold, lead, antimony, and some other metals. In addition, it has in the past been used for the treatment of Wilson's disease, a genetic disorder in which the body tends to retain copper.

Its original name reflects its origins as a compound secretly developed by British biochemists at Oxford University during World War II as an antidote for lewisite, a now-obsolete arsenic-based chemical warfare agent. Dimercaprol is on the World Health Organization's List of Essential Medicines, a list of the most important medication needed in a basic health system. Dimercaprol has long been the mainstay of chelation therapy for lead or arsenic poisoning, and it remains an essential drug. Nonetheless, because it can have serious adverse effects, researchers have also pursued development of less toxic analogues.

Biochemical function

Arsenic and some other heavy metals act by chemically reacting with adjacent thiol residues on metabolic enzymes, creating a chelate complex that inhibits the affected enzyme's activity. Dimercaprol competes with the thiol groups for binding the metal ion, which is then excreted in the urine.

Dimercaprol is itself toxic, with a narrow therapeutic range and a tendency to concentrate arsenic in some organs. Other drawbacks include the need to administer it by painful intramuscular injection. Serious side effects include nephrotoxicity and hypertension.

Dimercaprol has been found to form stable chelates in vivo with many other toxic metals including inorganic mercury, antimony, bismuth, cadmium, chromium, cobalt, gold, and nickel. However, it is not necessarily the treatment of choice for toxicity to these metals. Dimercaprol has been used as an adjunct in the treatment of the acute encephalopathy of lead toxicity. It is a potentially toxic drug, and its use may be accompanied by multiple side effects. Although treatment with dimercaprol will increase the excretion of cadmium, there is a concomitant increase in renal cadmium concentration, so that its use in case of cadmium toxicity is to be avoided. It does, however, remove inorganic mercury from the kidneys; but is not useful in the treatment of alkylmercury or phenyl mercury toxicity. Dimercaprol also enhances the toxicity of selenium and tellurium, so it is not to be used to remove these elements from the body.