AM251
AM251 (CAS: 183232-66-8), with the empirical formula C22H21N4OCl2I and a molecular weight of 555.24, is a selective CB1 cannabinoid receptor antagonist. This white solid compound is primarily used in research settings to investigate the endocannabinoid system's role in neurological processes. Its applications include studying its effects on neuronal activity and its potential modulation of memory and cognitive functions in preclinical models.
- IUPAC
- 1-(2,4-Dichlorophenyl)-5-(4-iodophenyl)-4-methyl-N-1-piperidinyl-1H-pyrazole-3-carboxamide

Neuroscience Research
AM251 is utilised in neurobiological studies to investigate the function of CB1 cannabinoid receptors in the central nervous system. It aids in understanding receptor-mediated signalling pathways relevant to memory and learning.
Pharmacological Tool
As a selective antagonist, AM251 serves as a valuable tool in pharmacological research for probing the effects of CB1 receptor blockade. It has been employed in studies examining its interaction with hippocampal neurons to enhance spatial memory in mice.
Cell Biology Studies
This compound can be applied in cell biology research to explore the impact of cannabinoid receptor signalling on cellular processes and neuronal excitability.
| Molecular weight | 555.24 |
|---|---|
| Empirical formula | C22H21N4OCl2I |
| Assay | >98% (HPLC) |
| Form | solid |
| Colour | white |
| Solubility | DMSO: >10 mg/mLH2O: insoluble |
| Application | AM251, a CB1 cannabinoid receptor antagonist, has been used in a study to determine its interaction with hippocampal neurons to enhance spatial memory in mice. |

Hazard statements
- H315Causes skin irritation
- H319Causes serious eye irritation
- H335May cause respiratory irritation
Precautionary statements
- P261Avoid breathing dust, fume, gas or vapours
- P305IF IN EYES
| Protective equipment | dust mask type N95 (US), Eyeshields, Gloves |
|---|---|
| Water hazard class (WGK, DE) | 3 |
| Hazard codes (EU) | Xi |
| Risk statements (R) | 36/37/38 |
| Safety statements (S) | 26-36 |
Hazard information is provided for guidance. Always consult the product Safety Data Sheet (SDS), available on request, before handling.
| Gene Information | mouse ... Cnr1(12801), Cnr2(12802)rat ... Cnr1(25248) |
|---|
Documentation
Every batch ships with a Certificate of Analysis covering assay, identity and purity; the grade is confirmed against your enquiry. Safety Data Sheets and technical data sheets are available on request.
Supply & logistics
Samples for technical evaluation; bulk MOQ by grade and packaging. In-stock material ships in 7–10 working days, worldwide, with full export documentation.
What is AM251 used for?
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AM251 is used as a selective CB1 cannabinoid receptor antagonist primarily in research settings to study the endocannabinoid system's role in neurological processes, including its effects on neuronal activity and memory.
What is the CAS number and molecular formula for AM251?
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The CAS number for AM251 is 183232-66-8, and its empirical formula is C22H21N4OCl2I.
What grade and purity does Tech Serve Solutions supply for AM251?
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Tech Serve Solutions supplies AM251 with an assay of >98% (HPLC). This product is intended for research purposes and is not represented as USP, BP, or EP grade.
How should AM251 be handled safely?
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AM251 is classified as a Warning substance, causing skin irritation (H315), serious eye irritation (H319), and respiratory irritation (H335). When handling, use a dust mask type N95 (US), wear eyeshields, and gloves. Ensure good ventilation and avoid breathing dust. In case of contact, rinse cautiously with water for several minutes.
How is AM251 packed, shipped, and exported?
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AM251 is supplied as a white solid. As a specialist global supplier, Tech Serve Solutions exports fine chemicals worldwide, adhering to all necessary shipping regulations and documentation for international transit.
How can I request a sample or quote for AM251?
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To request a sample or obtain a quote for AM251, please contact the Tech Serve Solutions sales team via our website or directly via email/phone, referencing the product name and CAS number.
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