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L5025

Sigma-Aldrich

Leflunomide

Immunosuppressant

Synonym(s):

5-Methylisoxazole-4-(4-trifluoromethyl)carboxanilide

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About This Item

Empirical Formula (Hill Notation):
C12H9F3N2O2
CAS Number:
75706-12-6
Molecular Weight:
270.21
MDL number:
MFCD00867593
UNSPSC Code:
12352202
PubChem Substance ID:
24278516
NACRES:
NA.77

Quality Level

200

Assay

≥98% (TLC)

form

powder

mp

166.5 °C

solubility

methanol: 19.60-20.40 mg/mL, clear, colorless to faintly yellow

Mode of action

enzyme | inhibits

storage temp.

2-8°C

SMILES string

Cc1oncc1C(=O)Nc2ccc(cc2)C(F)(F)F

InChI

1S/C12H9F3N2O2/c1-7-10(6-16-19-7)11(18)17-9-4-2-8(3-5-9)12(13,14)15/h2-6H,1H3,(H,17,18)

InChI key

VHOGYURTWQBHIL-UHFFFAOYSA-N

Gene Information

human ... DHODH(1723)

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Application

By virtue of its immunosuppressant effects, leflunomide has found use in organ transplantation and treatment of rheumatoid arthritis and other autoimmune diseases.

Biochem/physiol Actions

Immunosuppressive; inhibits T and B cell proliferation. Activity is attributed mainly to its metabolite, a malononitrile derivative, which is believed to inhibit dihydroorotate dehydrogenase (in the de novo pyrimidine synthesis pathway) as well as several protein tyrosine kinases.

Pictograms

Skull and crossbones
GHS06

Signal Word

Danger

Hazard Statements

H301,H315,H319,H335

Hazard Classifications

Acute Tox. 3 Oral - Eye Irrit. 2 - Skin Irrit. 2 - STOT SE 3

Target Organs

Respiratory system

Storage Class Code

6.1C - Combustible acute toxic Cat.3 / toxic compounds or compounds which causing chronic effects

WGK

WGK 1

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Certificates of Analysis (COA)

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K F Siemasko et al.
Transplantation, 61(4), 635-642 (1996-02-27)
Leflunomide is an immunosuppressive drug capable of inhibiting cellular and humoral mediated responses in vivo. The mechanism responsible for suppression of B cell antibody responses in vivo has not been identified. In this study we demonstrate that leflunomide functions to
J M Kremer et al.
Clinical and experimental rheumatology, 22(5 Suppl 35), S95-100 (2004-11-24)
Leflunomide was first shown to have disease-modifying properties in a rat model of adjuvant-induced arthritis. Leflunomide has been subsequently used with success in several animal models of tissue and organ allograft and of autoimmune disease including collagen- and adjuvant-induced arthritis
Nicolae Leca
Current opinion in organ transplantation, 14(4), 370-374 (2009-06-11)
Leflunomide has been used off-label in renal transplantation because of the attractive combination of antiviral and immunosuppressive effects. This study intends to review the clinical applications of leflunomide with interest to transplantation. In renal transplantation, particularly in BK nephropathy, the
T R Brazelton et al.
Current opinion in immunology, 8(5), 710-720 (1996-10-01)
Among all the new immunosuppressive molecules being investigated either preclinically or clinically, four stand out: tacrolimus (FK506), sirolimus (rapamycin), mycophenolate mofetil and leflunomide (and its malononitriloamide analogs). Each drug has distinct mechanisms of immunosuppressive action, and in the past year
X Xu et al.
Biochemical pharmacology, 52(4), 527-534 (1996-08-23)
Previous studies have demonstrated that the active metabolite of leflunomide, A77 1726 [N-(4-trifluoromethylphenyl-2-cyano-3-hydroxycrotoamide)], is capable of inhibiting the activities of tyrosine kinases and dihydroorotate dehydrogenase (DHO-DHase). In the present study, we define the relative contribution of these activities to the
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