Catalog Number: 3858
Chemical Name: 1-Methyl-N-[2-methyl-4-[2-(2-methylphenyl)diazenyl]phenyl-1H-pyrazole-5-carboxamide
Biological Activity
Potent aryl hydrocarbon receptor (AhR) antagonist (IC50 = 30 nM). Exhibits no AhR agonist-like activity (at concentrations up to 100 μM). Inhibits 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD)-induced AhR-dependent transcription in vitro and reduces TCDD-induced toxicity in vivo. Attenuates Th17 differentiation of naive CD4 T cells and promotes expansion of hematopoietic stem cells in vitro.
Technical Data
  • M.Wt:
  • Formula:
  • Solubility:
    Soluble to 100 mM in DMSO and to 10 mM in ethanol
  • Purity:
  • Storage:
    Store at +4°C
  • CAS No:
The technical data provided above is for guidance only. For batch specific data refer to the Certificate of Analysis. All Tocris products are intended for laboratory research use only.
Background References
  1. CXCR4 activation maintains a stem cell population in tamoxifen-resistant breast cancer cells through AhR signalling.
    Dubrovska A, Hartung A, Bouchez LC
    Br. J. Cancer, 2012;107(1):43-52.
  2. Novel compound 2-methyl-2H-pyrazole-3-carboxylic acid (2-methyl-4-o-tolylazo-phenyl)-amide (CH-223191) prevents 2,3,7,8-TCDD-induced toxicity by antagonizing the aryl hydrocarbon receptor.
    Kim et al.
    Mol.Pharmacol., 2006;69:1871
  3. Natural agonists for aryl hydrocarbon receptor in culture medium are essential for optimal differentiation of TH17 T cells.
    Veldhoen et al.
    J.Exp.Med., 2009;206:43
  4. Aryl hydrocarbon receptor antagonists promote the expansion of human hematopoietic stem cells.
    Boitano et al.
    Science, 2010;329:1345

The citations listed below are publications that use Tocris products. Selected citations for CH 223191 include:

3 Citations: Showing 1 - 3
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  1. A TDO2-AhR Signaling Axis Facilitates Anoikis Resistance and Metastasis in Triple-Negative Breast Cancer.
    Authors: D'Amato Et al.
    Cancer Res 2015;75:4651
  2. IDO1 suppresses inhibitor development in hemophilia A treated with factor VIII.
    Authors: Matino Et al.
    Br J Pharmacol 2015;125:3766
  3. Regulation of plasmacytoid dendritic cell development in mice by aryl hydrocarbon receptor.
    Authors: Liu Et al.
    Immunol Cell Biol 2014;92:200

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