Pricing Availability   Qty
Cat.No. 2228 - Leflunomide | C12H9F3N2O2 | CAS No. 75706-12-6
Description: Inhibitor of DHODH
Alternative Names: HWA 486, RS-34821
Chemical Name: 5-Methyl-N-[4-(trifluoromethyl)phenyl]-4-isoxazolecarboxamide
Purity: ≥99% (HPLC)
Citations (1)
Literature (2)

Biological Activity

Inhibitor of dihydroorotate dehydrogenase (IC50 = 2.5 μM). Inhibits de novo pyrimidine synthesis in human T cells in vitro; also inhibits lymphocyte proliferation. Exhibits efficacy in several animal models of autoimmune disease, arthritis and graft rejection. Active metabolite, teriflunomide (A77 1726, Cat. No. 5069), also available.

Technical Data

M. Wt 270.21
Formula C12H9F3N2O2
Storage Store at +4°C
Purity ≥99% (HPLC)
CAS Number 75706-12-6
PubChem ID 3899
Smiles CC1=C(C=NO1)C(=O)NC1=CC=C(C=C1)C(F)(F)F

The technical data provided above is for guidance only. For batch specific data refer to the Certificate of Analysis.

Tocris products are intended for laboratory research use only, unless stated otherwise.

Solubility Data

Solvent Max Conc. mg/mL Max Conc. mM
ethanol 27.01 100
DMSO 27.01 100

Preparing Stock Solutions

The following data is based on the product molecular weight 270.21. 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.

Select a batch to recalculate based on the batch molecular weight:
Concentration / Solvent Volume / Mass 1 mg 5 mg 10 mg
1 mM 3.7 mL 18.5 mL 37.01 mL
5 mM 0.74 mL 3.7 mL 7.4 mL
10 mM 0.37 mL 1.85 mL 3.7 mL
50 mM 0.07 mL 0.37 mL 0.74 mL

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.


References are publications that support the biological activity of the product.

Greene et al (1995) Inhibition of dihydroorotate dehydrogenase by the immunosuppressive agent leflun. Biochem.Pharmacol. 50 861 PMID: 7575649

Cherwinski et al (1995) The immunosuppressant leflun. inhibits lymphocyte proliferation by inhibiting pyrimidine biosynthesis. J.Pharmacol.Exp.Ther. 275 1043 PMID: 7473131

Brazelton and Morris (1996) Molecular mechanisms of action of new xenobiotic immunosuppressive drugs: tacro. (FK506), siro. (rapamycin), mycophen. mofetil and leflun. Curr.Opin.Immunol. 8 710 PMID: 8902398

If you know of a relevant reference for Leflunomide, please let us know.

View Related Products by Product Action

View all Dihydroorotate Dehydrogenase Inhibitors

Keywords: Leflunomide, Leflunomide supplier, Dihydroorotate, inhibitors, inhibits, dehydrogenases, DHOD, HWA486, immunosuppressants, HWA, 486, RS-34821, Immunosuppressants, Dihyroorotate, Dehydrogenase, DNA,, RNA, and, Protein, Synthesis, 2228, Tocris Bioscience

1 Citation for Leflunomide

Citations are publications that use Tocris products. Selected citations for Leflunomide include:

Risse et al (2011) Interleukin-13 inhibits proliferation and enhances contractility of human airway smooth muscle cells without change in contractile phenotype. J Biomol Res Ther 300 L958 PMID: 21460123

Do you know of a great paper that uses Leflunomide from Tocris? Please let us know.

Reviews for Leflunomide

There are currently no reviews for this product. Be the first to review Leflunomide and earn rewards!

Have you used Leflunomide?

Submit a review and receive an Amazon gift card.

$50/€35/£30/$50CAN/¥300 Yuan/¥5000 Yen for first to review with an image

$25/€18/£15/$25CAN/¥75 Yuan/¥1250 Yen for a review with an image

$10/€7/£6/$10 CAD/¥70 Yuan/¥1110 Yen for a review without an image

Submit a Review

Literature in this Area

Tocris offers the following scientific literature in this area to showcase our products. We invite you to request* or download your copy today!

*Please note that Tocris will only send literature to established scientific business / institute addresses.

Multiple Sclerosis

Multiple Sclerosis Poster

Multiple sclerosis (MS) is an autoimmune disease that is characterized by focal demyelination and axon degeneration in the central nervous system. This poster summarizes the neurobiology and current therapies of MS.

Rheumatoid Arthritis

Rheumatoid Arthritis Poster

Rheumatoid arthritis (RA) is a chronic destructive inflammatory autoimmune disease that results from a breakdown in immune tolerance, for reasons that are as yet unknown. This poster summarizes the pathology of RA and the inflammatory processes involved, as well as describing some of the epigenetic modifications associated with the disease and the potential for targeting these changes in the discovery of new treatments.