AM 251

Cat. No. 1117

AM 251 C22H21Cl2IN4O [183232-66-8]

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Chemical Name: N-(Piperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide

Biological Activity

Potent CB1 receptor antagonist (IC50 = 8 nM, Ki = 7.49 nM) that displays 306-fold selectivity over CB2 receptors. Also potent GPR55 agonist (EC50 = 39 nM). Also available in a fluorescent form (Cat. No. 2540).

Technical Data

Soluble to 25 mM in ethanol and to 100 mM in DMSO
>99 %
Store at RT

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.

Certificate of Analysis / Safety Data Sheet

Certificate of Analysis: View current batch
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Safety Data Sheet: View Safety Data Sheet


Gatley et al (1996) 125I-labeled AM 251: a radioiodinated ligand which binds in vivo to mouse brain cannabinoid CB1 receptors. Eur.J.Pharmacol. 307 331. PMID: 8836622.

Gatley et al (1997) Binding of the non-classical cannabinoid CP 55,940, and the diarylpyrazole AM251 to rodent brain cannabinoid receptors. Life Sci. 61 191. PMID: 9335234.

Lan et al (1999) Structure-activity relationships of pyrazole derivatives as cannabinoid receptor antagonists. J.Med.Chem. 42 769. PMID: 10052983.

Pertwee (2005) Inverse agonism and neutral antagonism at cannabinoid CB1 receptors. Life Sci. 76 1307. PMID: 15670612.

Ryberg et al (2007) The orphan receptor GPR55 is a novel cannabinoid receptor. Br.J.Pharmacol. 152 1092. PMID: 17876302.

If you know of a relevant citation for this product please let us know.

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Keywords: AM 251, supplier, Potent, CB1, antagonist, GPR55, agonist, cannabinoid, receptors, AM251, cb1r, CB1 Receptor Antagonists

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