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

MedKoo CAT#: 205895

CAS#: 870262-90-1

Description: Letaxaban, also known as TAK-442, is a potent, selective, and orally active factor Xa inhibitor, which is a tetrahydropyrimidin-2(1H)-one derivative. TAK-442 inhibited endogenous FXa activity in platelet-poor human [half-maximal inhibitory concentration (IC(50)): 53 nM, TAK-442 ] and rat (IC(50): 32 nM, TAK-442 ) plasma. TAK-442 inhibited in vitro reconstituted human prothrombinase (system included FXa, calcium, and washed platelets) with an IC(50) value of 51 nM. In a rat model of balloon injury, thrombin activity on the surface of injured vessels increased to 3.2-, 22-, and 5.8-fold the activity on the surface of the intact aorta at 5 minutes, 1 hour, and 24 hours after the injury, respectively. At approximately 1 hour after the injury, TAK-442 blocked platelet-associated thrombin generation on the surface of injured aortas with an IC(50) value of 19 nM. (source: J Cardiovasc Pharmacol. 2011 Feb;57(2):201-6.)

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Letaxaban is not in stock, but may be available through custom synthesis. For cost-effective reason, minimum 1 gram order is requested. The product will be characterized by NMR, HPLC and MS analysis. Purity (HPLC) is usually >98%. CoA, QC data, MSDS will be provided when product is successfully made. The estimated lead time is 2-3 months. Please send email to sales@medkoo.com to inquire quote.

Chemical Structure


Theoretical Analysis

MedKoo Cat#: 205895
Name: Letaxaban
CAS#: 870262-90-1
Chemical Formula: C22H26ClN3O5S
Exact Mass: 479.12817
Molecular Weight: 479.98
Elemental Analysis: C, 55.05; H, 5.46; Cl, 7.39; N, 8.75; O, 16.67; S, 6.68

Synonym: Letaxaban TAK442; TAK 442; TAK-442.

IUPAC/Chemical Name: (S)-1-(1-(3-((6-chloronaphthalen-2-yl)sulfonyl)-2-hydroxypropanoyl)piperidin-4-yl)tetrahydropyrimidin-2(1H)-one


InChi Code: InChI=1S/C22H26ClN3O5S/c23-17-4-2-16-13-19(5-3-15(16)12-17)32(30,31)14-20(27)21(28)25-10-6-18(7-11-25)26-9-1-8-24-22(26)29/h2-5,12-13,18,20,27H,1,6-11,14H2,(H,24,29)/t20-/m1/s1


Technical Data

Solid powder


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).

Soluble in DMSO, not in water

Shelf Life:
>5 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).

Harmonized System Code:

Additional Information



1: Deftereos S, Bouras G, Giannopoulos G, Kossyvakis C, Panagopoulou V, Pyrgakis V, Stefanadis C. Novel oral anticoagulants in the treatment of acute coronary syndromes: is there any room for new anticoagulants? Curr Clin Pharmacol. 2012 Aug;7(3):195-208. PubMed PMID: 22564121.

2: Konishi N, Hiroe K, Kawamura M. Effects of fondaparinux and a direct factor Xa inhibitor TAK-442 on platelet-associated prothrombinase in the balloon-injured artery of rats. J Cardiovasc Pharmacol. 2011 Feb;57(2):201-6. PubMed PMID: 21052010.

3: Zufferey PJ, Samama CM, Rosencher N. Improve the results of phase II trials of thromboprophylaxis with the new oral anticoagulant drugs. Thromb Haemost. 2010 Dec;104(6):1083-4. Epub 2010 Sep 30. PubMed PMID: 20886198.

4: Weitz JI, Cao C, Eriksson BI, Fisher W, Kupfer S, Raskob G, Spaeder J, Turpie AG. A dose-finding study with TAK-442, an oral factor Xa inhibitor, in patients undergoing elective total knee replacement surgery. Thromb Haemost. 2010 Dec;104(6):1150-7. Epub 2010 Sep 30. PubMed PMID: 20886185.

5: Konishi N, Hiroe K, Kawamura M. Differential effects of TAK-442, a novel orally active direct factor Xa inhibitor, and ximelagatran, a thrombin inhibitor, on factor V-mediated feedback on coagulation cascade and bleeding. Thromb Haemost. 2010 Sep;104(3):504-13. Epub 2010 Jul 20. PubMed PMID: 20664909.

6: Konishi N, Hiroe K, Kawamura M. Synergistic effect of a factor Xa inhibitor, TAK-442, and antiplatelet agents on whole blood coagulation and arterial thrombosis in rats. Thromb Res. 2010 Aug;126(2):124-9. Epub 2010 May 10. PubMed PMID: 20452654.

7: Kawamura M, Konishi N, Hiroe K, Shofuda K, Imaeda Y, Fujimoto T, Kubo K. Antithrombotic and anticoagulant profiles of TAK-442, a novel factor Xa inhibitor, in a rabbit model of venous thrombosis. J Cardiovasc Pharmacol. 2010 Aug;56(2):156-61. Erratum in: J Cardiovasc Pharmacol. 2010 Oct;56(4):439. PubMed PMID: 20410831.

8: Fujimoto T, Imaeda Y, Konishi N, Hiroe K, Kawamura M, Textor GP, Aertgeerts K, Kubo K. Discovery of a tetrahydropyrimidin-2(1H)-one derivative (TAK-442) as a potent, selective, and orally active factor Xa inhibitor. J Med Chem. 2010 May 13;53(9):3517-31. PubMed PMID: 20355714.

9: Perzborn E. Factor Xa inhibitors--new anticoagulants for secondary haemostasis. Hamostaseologie. 2009 Aug;29(3):260-7. PubMed PMID: 19644596.

10: Gómez-Outes A, Lecumberri R, Pozo C, Rocha E. New anticoagulants: focus on venous thromboembolism. Curr Vasc Pharmacol. 2009 Jul;7(3):309-29. Review. PubMed PMID: 19601856.

11: Eriksson BI, Quinlan DJ, Weitz JI. Comparative pharmacodynamics and pharmacokinetics of oral direct thrombin and factor xa inhibitors in development. Clin Pharmacokinet. 2009;48(1):1-22. doi: 10.2165/0003088-200948010-00001. Review. PubMed PMID: 19071881.