A7257 Sigma-Aldrich


≥98%, crystalline

Synonym: (R)-4-(2-Amino-1-hydroxyethyl)-1,2-benzenediol, L-Arterenol, L-Noradrenaline, Levarterenol

  • CAS Number 51-41-2

  • Empirical Formula (Hill Notation) C8H11NO3

  • Molecular Weight 169.18

  •  Beilstein/REAXYS Number 2804840

  •  EC Number 200-096-6

  •  MDL number MFCD00025592

  •  PubChem Substance ID 24891196

  •  NACRES NA.77



Related Categories Adrenergics, Adrenergics - Agonists, Agonists, Bioactive Small Molecule Alphabetical Index, Bioactive Small Molecules,
assay   ≥98%
form   crystalline
color   off-white to tan
storage temp.   −20°C
Gene Information   human ... ADRA2A(150), ADRA2B(151), ADRA2C(152)
rat ... Adra1a(29412), Adra1d(29413), Adra2a(25083), Adrb1(24925), Adrb2(24176), Drd1a(24316), Drd2(24318)



Norepinephrine is an adrenergic neurotransmitter used in the treatment of hypotension, depression, schizophrenia, and attention deficit/hyperactivity disorders.


1, 5 g in poly bottle

500 mg in poly bottle

Biochem/physiol Actions

Adrenergic neurotransmitter

Features and Benefits

This compound is a featured product for Neuroscience research. Click here to discover more featured Neuroscience products. Learn more about bioactive small molecules for other areas of research at

Safety & Documentation

Safety Information

GHS06  GHS06
Signal word 
Hazard statements 
Precautionary statements 
UN 2811 6.1 / PGII
WGK Germany 


Certificate of Analysis (COA)

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Certificate of Origin (COO)

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Frequently Asked Questions

Which document(s) contains shelf-life or expiration date information for a given product?
If available for a given product, the recommended re-test date or the expiration date can be found on the Certificate of Analysis.
How do I get lot-specific information or a Certificate of Analysis?
The lot specific COA document can be found by entering the lot number above under the "Documents" section.
How should Product A7257,(-)-Norepinephrine, be dissolved?
This product is soluble in 0.5M HCl at a concentration of 50mg/mL, yielding a clear faint yellow solution.
What are the differences between Product No. A7257, (-)-Norepinephrine and Product No. A0937, (±)-Norepinephrine (+)-bitartrate salt?
Product No. A7257, is the free base form of the (-) isomer; it is not water soluble. Product No. A0937 is the bitartrate salt of the racemic (+/-) mixture; it is soluble in water at a concentration of 50 mg/mL.
How long is a solution of Product A7257, (-)-Norepinephrine, stable?
A stock solution of 1 mg/ml or greater may be stored frozen in aliquots. Avoid freeze-thaw cycles. When the solution gets a pink cast, the product has degraded.
How do I find price and availability?
There are several ways to find pricing and availability for our products.Once you log onto our website, you will find the price and availability displayed on the product detail page.You can contact any of our Customer Sales and Service offices to receive a quote. USA customers: 1-800-325-3010 orview local office numbers.
What is the Department of Transportation shipping information for this product?
Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product.
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