AM 251

Name: AM 251
Brand: Tocris Bioscience
SKU: 1117
Rating: 5 (1 reviews)

Tocris Bioscience, part of Bio-Techne | Catalog # 1117

(1)

Citations (1198)

COA / SDS

Potent CB1 antagonist; also GPR55 agonist

Key Product Details

Description:	Potent CB₁ antagonist; also GPR55 agonist
Chemical Name:	N-(Piperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide
Purity:	≥98% (HPLC)
Molecular Weight:	555.24

View Full Technical Details for AM 251

Technical Data
Citations / Reviews (1)

Biological Activity for AM 251

AM 251 is a potent CB₁ receptor antagonist (IC₅₀ = 8 nM, K_i = 7.49 nM) that displays 306-fold selectivity over CB₂ receptors. Also potent GPR55 agonist (EC₅₀ = 39 nM) and μ-opioid receptor antagonist (K_i = 251 nM).

Fluorescent Form also available.

Technical Data for AM 251

M. Wt	555.24
Formula	C₂₂H₂₁Cl₂IN₄O
Storage	Store at RT
Purity	≥98% (HPLC)
CAS Number	183232-66-8
PubChem ID	2125
InChi Key	BUZAJRPLUGXRAB-UHFFFAOYSA-N
Smiles	CC1=C(N(N=C1C(=O)NN1CCCCC1)C1=C(Cl)C=C(Cl)C=C1)C1=CC=C(I)C=C1

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 for AM 251

	Solvent	Max Conc. mg/mL	Max Conc. mM
Solubility
	ethanol	13.88	25
	DMSO	55.52	100

Preparing Stock Solutions for AM 251

The following data is based on the product molecular weight 555.24.

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	1.80 mL	9.01 mL	18.01 mL
5 mM	0.36 mL	1.80 mL	3.60 mL
10 mM	0.18 mL	0.90 mL	1.80 mL
50 mM	0.04 mL	0.18 mL	0.36 mL

Molarity Calculator

Calculate the mass, volume, or concentration required for a solution.

Mass

Concentration

Volume

M. Wt*

g/mol

*When preparing stock solutions always use the batch-specific molecular weight of the product found on the vial label and CoA (available online).

Dilution Calculator

Calculate the dilution required to prepare a stock solution.

Concentration 1 (C1)

Volume 1 (V1)

Concentration 2 (C2)

Volume 2 (V2)

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.

Volume (to add to vial)

Mass (in vial)

Desired Reconstitution Concentration

References for AM 251

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

Seely AM-251 and rimon. act as direct antagonists at mu-opioid receptors: implications for opioid/cannabinoid interaction studies. Neuropharmacology 2012 PMID: 22771770
Ellermann Endocannabinoids inhibit the induction of virulence in enteric pathogens. Cell 2020 PMID: 33031742
Ryberg The orphan receptor GPR55 is a novel cannabinoid receptor. Br.J.Pharmacol. 2007 PMID: 17876302
Gatley Binding of the non-classical cannabinoid CP 55,940, and the diarylpyrazole AM251 to rodent brain cannabinoid receptors. Life Sci. 1997 PMID: 9335234
Pertwee Inverse agonism and neutral antagonism at cannabinoid CB₁ receptors. Life Sci. 2005 PMID: 15670612
Lan Structure-activity relationships of pyrazole derivatives as cannabinoid receptor antagonists. J.Med.Chem. 1999 PMID: 10052983
Gatley ¹²⁵I-labeled AM 251: a radioiodinated ligand which binds in vivo to mouse brain cannabinoid CB₁ receptors. Eur.J.Pharmacol. 1996 PMID: 8836622