WARNING: This product is for research use only, not for human or veterinary use.

MedKoo CAT#: 461450

CAS#: 3639-19-8

Description: Difetarsone is an antiprotozoal agent. Various studies have shown it to be particularly effective against Trichuris trichiura, commonly known as the whipworm. It has also been used to treat Entamoeba histolytica infections. Prior to the drugs use in the early 1970s, there were few effective treatments for this infection. Difetarsone often has minor side effects, which include rashes, nausea and vomiting. It has also resulted in angioedema in at least one known case.

Chemical Structure

CAS# 3639-19-8

Theoretical Analysis

MedKoo Cat#: 461450
Name: Difetarsone
CAS#: 3639-19-8
Chemical Formula: C14H18As2N2O6
Exact Mass: 459.9597
Molecular Weight: 460.14
Elemental Analysis: C, 36.54; H, 3.94; As, 32.56; N, 6.09; O, 20.86

Price and Availability

Size Price Availability Quantity
5.0mg USD 150.0 Ready to ship
10.0mg USD 250.0 Ready to ship
25.0mg USD 550.0 Ready to ship
50.0mg USD 950.0 Ready to ship
100.0mg USD 1650.0 Ready to ship
200.0mg USD 2650.0 Ready to ship
Bulk inquiry

Synonym: Difetarsone; Difetarsonum; Diphetarson; RP 4763; RP-4763; RP4763; Benarsal;

IUPAC/Chemical Name: ((ethane-1,2-diylbis(azanediyl))bis(4,1-phenylene))diarsonic acid


InChi Code: InChI=1S/C14H18As2N2O6/c19-15(20,21)11-1-5-13(6-2-11)17-9-10-18-14-7-3-12(4-8-14)16(22,23)24/h1-8,17-18H,9-10H2,(H2,19,20,21)(H2,22,23,24)

SMILES Code: O=[As](C1=CC=C(NCCNC2=CC=C([As](O)(O)=O)C=C2)C=C1)(O)O

Appearance: Solid powder

Purity: >98% (or refer to the Certificate of Analysis)

Shipping Condition: Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition: Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Solubility: Soluble in DMSO

Shelf Life: >3 years if stored properly

Drug Formulation: This drug may be formulated in DMSO

Stock Solution Storage: 0 - 4 C for short term (days to weeks), or -20 C for long term (months).

HS Tariff Code: 2934.99.03.00

Biological target: Difetarsone is an antiprotozoal agent.
In vitro activity: TBD
In vivo activity: TBD

Solubility Data

Solvent Max Conc. mg/mL Max Conc. mM
DMSO 0.0 0.0

Preparing Stock Solutions

The following data is based on the product molecular weight 460.14 Batch specific molecular weights may vary from batch to batch due to the degree of hydration, which will affect the solvent volumes required to prepare stock solutions.

Recalculate based on batch purity %
Concentration / Solvent Volume / Mass 1 mg 5 mg 10 mg
1 mM 1.15 mL 5.76 mL 11.51 mL
5 mM 0.23 mL 1.15 mL 2.3 mL
10 mM 0.12 mL 0.58 mL 1.15 mL
50 mM 0.02 mL 0.12 mL 0.23 mL
Formulation protocol: TBD
In vitro protocol: TBD
In vivo protocol: TBD

Molarity Calculator

Calculate the mass, volume, or concentration required for a solution.

*When preparing stock solutions always use the batch-specific molecular weight of the product found on the vial label and SDS / CoA (available online).

Reconstitution Calculator

The reconstitution calculator allows you to quickly calculate the volume of a reagent to reconstitute your vial. Simply enter the mass of reagent and the target concentration and the calculator will determine the rest.


Dilution Calculator

Calculate the dilution required to prepare a stock solution.

1: Vandepitte J, Thienpont D. Trichuris infestations and difetarsone. Br Med J. 1972 Dec 2;4(5839):549. PubMed PMID: 4642803; PubMed Central PMCID: PMC1788733.

2: Leary PM, Jones C, Douglas F, Boyd ST. Difetarsone in outpatient treatment of Trichuris trichiura infestation. Arch Dis Child. 1974 Jun;49(6):486-8. PubMed PMID: 4851370; PubMed Central PMCID: PMC1648795.

3: Leary PM, Elsworth M, Maytham D, Jones C, Douglas F, Boyd S. Difetarsone in the treatment of Trichuris trichiura. S Afr Med J. 1973 Aug 11;47(31):1389. PubMed PMID: 4578732.

4: Boyce JM, Fitzgerald TC, Gregg R. Difetarsone ('Bemarsal') and other anthelminthic drugs in the treatment of Trichuris trichiura (whipworm) infestation in a subnormality hospital. Br J Psychiatry. 1974 Feb;124(579):160-5. PubMed PMID: 4825661.

5: Vandepitte J, Gatti F, Krubwa F, Thienpont D. Letter: Difetarsone in the treatment of Trichuris trichiura. S Afr Med J. 1973 Nov 24;47(46):2205. PubMed PMID: 4760912.

6: Rubidge CJ, O'Dowd PB, Powell SJ. Difetarsone in the treatment of Trichuris trichiura infections. S Afr Med J. 1973 Jun 16;47(23):991-2. PubMed PMID: 4714286.

7: Lynch DM, Green EA, McFadzean JA, Pugh IM. Trichuris trichiura infestations in the United Kingdom and treatment with difetarsone. Br Med J. 1972 Oct 14;4(5832):73-6. PubMed PMID: 5077469; PubMed Central PMCID: PMC1786249.

8: Vetter D, Arpin MP, Doffoël M, Charrault A, Biour M, Bockel R. [Prolonged hepatitis after ingestion of diphetarsone]. Gastroenterol Clin Biol. 1988 Feb;12(2):173-4. French. PubMed PMID: 3366319.

9: Labadie H, Dyan S, Novello P, Pouteau M, Licht H. [Diphetarsone-induced hepatitis. A second case]. Presse Med. 1992 Jun 6;21(21):996. French. PubMed PMID: 1386461.