WARNING: This product is for research use only, not for human or veterinary use.

MedKoo CAT#: 510338

CAS#: 183232-66-8

Description: AM251 is a cannabinoid receptor antagonist. AM251 improves recognition memory in rats and produces nocifensive behavior via activation of ERK signaling pathway. Moreover, AM251 alters mitochondrial physiology via proteolytic degradation of ERRα and attenuates mechanical allodynia and thermal hyperalgesia after burn injury.

Chemical Structure

CAS# 183232-66-8

Theoretical Analysis

MedKoo Cat#: 510338
Name: AM251
CAS#: 183232-66-8
Chemical Formula: C22H21Cl2IN4O
Exact Mass: 554.01371
Molecular Weight: 555.24
Elemental Analysis: C, 47.59; H, 3.81; Cl, 12.77; I, 22.86; N, 10.09; O, 2.88

Size Price Shipping out time Quantity
10mg USD 150 2 Weeks
25mg USD 250 2 Weeks
50mg USD 450 2 Weeks
100mg USD 650 2 Weeks
200mg USD 950 2 Weeks
500mg USD 1650 2 Weeks
1g USD 2850 2 Weeks
2g USD 4350 2 Weeks
5g USD 9750 2 Weeks
Inquire bulk and customized quantity

Pricing updated 2021-03-06. Prices are subject to change without notice.

AM251, purity > 98%, is in stock. Current shipping out time is about 2 weeks after order is received. CoA, QC data and MSDS documents are available in one week after order is received.

Synonym: AM251; AM 251; AM-251.

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


InChi Code: InChI=1S/C22H21Cl2IN4O/c1-14-20(22(30)27-28-11-3-2-4-12-28)26-29(19-10-7-16(23)13-18(19)24)21(14)15-5-8-17(25)9-6-15/h5-10,13H,2-4,11-12H2,1H3,(H,27,30)


Solid powder

>98% (or refer to the Certificate of Analysis)

Shipping Condition:
Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition:
Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Soluble in DMSO, not in water

Shelf Life:
>2 years if stored properly

Drug Formulation:
This drug may be formulated in DMSO

Stock Solution Storage:
0 - 4 C for short term (days to weeks), or -20 C for long term (months).

HS Tariff Code:

Handling Instructions:

Preparing Stock Solutions

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 1.15 mL 5.76 mL 11.51 mL
5 mM 0.23 mL 1.15 mL 2.3 mL
10 mM 0.12 mL 0.58 mL 1.15 mL
50 mM 0.02 mL 0.12 mL 0.23 mL

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1: Liu J, Pope C. The cannabinoid receptor antagonist AM251 increases paraoxon and chlorpyrifos oxon toxicity in rats. Neurotoxicology. 2015 Jan;46:12-8. doi: 10.1016/j.neuro.2014.11.001. Epub 2014 Nov 20. PubMed PMID: 25447325.

2: Ren Y, Wang J, Xu PB, Xu YJ, Miao CH. Systemic or intra-amygdala infusion of an endocannabinoid CB1 receptor antagonist AM251 blocked propofol-induced anterograde amnesia. Neurosci Lett. 2015 Jan 1;584:287-91. doi: 10.1016/j.neulet.2014.11.001. Epub 2014 Nov 6. PubMed PMID: 25445359.

3: Ueda M, Iwasaki H, Wang S, Murata E, Poon KY, Mao J, Martyn JA. Cannabinoid receptor type 1 antagonist, AM251, attenuates mechanical allodynia and thermal hyperalgesia after burn injury. Anesthesiology. 2014 Dec;121(6):1311-9. doi: 10.1097/ALN.0000000000000422. PubMed PMID: 25188001; PubMed Central PMCID: PMC4237656.

4: Ratano P, Everitt BJ, Milton AL. The CB1 receptor antagonist AM251 impairs reconsolidation of pavlovian fear memory in the rat basolateral amygdala. Neuropsychopharmacology. 2014 Oct;39(11):2529-37. doi: 10.1038/npp.2014.103. Epub 2014 May 7. PubMed PMID: 24801769; PubMed Central PMCID: PMC4149486.

5: Krzysik-Walker SM, González-Mariscal I, Scheibye-Knudsen M, Indig FE, Bernier M. The biarylpyrazole compound AM251 alters mitochondrial physiology via proteolytic degradation of ERRα. Mol Pharmacol. 2013 Jan;83(1):157-66. doi: 10.1124/mol.112.082651. Epub 2012 Oct 12. PubMed PMID: 23066093; PubMed Central PMCID: PMC3533472.

6: Aydin C, Oztan O, Isgor C. Nicotine-induced anxiety-like behavior in a rat model of the novelty-seeking phenotype is associated with long-lasting neuropeptidergic and neuroplastic adaptations in the amygdala: effects of the cannabinoid receptor 1 antagonist AM251. Neuropharmacology. 2012 Dec;63(8):1335-45. doi: 10.1016/j.neuropharm.2012.08.016. Epub 2012 Aug 31. PubMed PMID: 22959963; PubMed Central PMCID: PMC3697052.

7: Naderi N, Majidi M, Mousavi Z, Khoramian Tusi S, Mansouri Z, Khodagholi F. The interaction between intrathecal administration of low doses of palmitoylethanolamide and AM251 in formalin-induced pain related behavior and spinal cord IL1-β expression in rats. Neurochem Res. 2012 Apr;37(4):778-85. doi: 10.1007/s11064-011-0672-2. Epub 2011 Dec 27. PubMed PMID: 22201038.

8: Bialuk I, Winnicka MM. AM251, cannabinoids receptors ligand, improves recognition memory in rats. Pharmacol Rep. 2011;63(3):670-9. PubMed PMID: 21857077.

9: Raffa RB, Ward SJ. CB₁-independent mechanisms of Δ⁹-THCV, AM251 and SR141716 (rimonabant). J Clin Pharm Ther. 2012 Jun;37(3):260-5. doi: 10.1111/j.1365-2710.2011.01284.x. Epub 2011 Jul 11. Review. PubMed PMID: 21740450.

10: Dono LM, Currie PJ. The cannabinoid receptor CB₁ inverse agonist AM251 potentiates the anxiogenic activity of urocortin I in the basolateral amygdala. Neuropharmacology. 2012 Jan;62(1):192-9. doi: 10.1016/j.neuropharm.2011.06.019. Epub 2011 Jul 1. PubMed PMID: 21736884.

Additional Information