• USA Home
  • P7791 - Prazosin hydrochloride

P7791 Sigma-Aldrich

Prazosin hydrochloride

≥99.0% (HPLC)

Synonym: 1-(4-Amino-6,7-dimethoxy-2-quinazolinyl)-4-(2-furanylcarbonyl)piperazine hydrochloride, Furazosin hydrochloride

  • CAS Number 19237-84-4

  • Empirical Formula (Hill Notation) C19H21N5O4 · HCl

  • Molecular Weight 419.86

  •  Beilstein/REAXYS Number 4303561

  •  EC Number 242-903-4

  •  MDL number MFCD00058177

  •  PubChem Substance ID 24277793

  •  NACRES NA.77



Related Categories Adrenergics, Adrenergics - Antagonists, Antagonists- Adrenergics, Approved Therapeutics/Drug Candidates, Bioactive Small Molecule Alphabetical Index,
Quality Level   100
assay   ≥99.0% (HPLC)
solubility   H2O: 0.5 mg/mL
  methanol: 6 mg/mL
  dilute aqueous acid: insoluble
originator   Pfizer
SMILES string   Cl.COc1cc2nc(nc(N)c2cc1OC)N3CCN(CC3)C(=O)c4ccco4
InChI   1S/C19H21N5O4.ClH/c1-26-15-10-12-13(11-16(15)27-2)21-19(22-17(12)20)24-7-5-23(6-8-24)18(25)14-4-3-9-28-14;/h3-4,9-11H,5-8H2,1-2H3,(H2,20,21,22);1H
Gene Information   human ... ADRA1A(148), ADRA1B(147), ADRA1D(146)


General description

Prazosin is a member of the class of α-adrenergic blockers. It is considered as a peripheral vasodilator antihypertensive agent. Prazosin is a derivative of quinazoline.


Prazosin hydrochloride has been used:
• to block the α1adrenergic receptors that mediate sympathetic vasoconstriction in mice
• as an α1-adrenoceptor blocker,administered intragastrically in rats
• as a vasodilator,administered together with inuslin into the left ventricle of mice for the assessment of its effects on renal functions

Biochem/physiol Actions

Peripheral α1-adrenoceptor antagonist; vasodilator. Prazosin can be used to treat chronic posttraumatic stress disorder (PTSD). It plays a role in reducing blood pressure by relaxing blood vessels, hence used in the treatment of high blood pressure.

Features and Benefits

This compound is a featured product for ADME Tox and Neuroscience research. Discover more featured ADME Tox and Neuroscience products. Learn more about bioactive small molecules for other areas of research at sigma.com/discover-bsm.

This compound is also offered as part of Sigma′s Library of Pharmacologically Active Compounds (LOPAC®1280), a biologically annotated collection of high-quality, ready-to-screen compounds. Click here to learn more.

This compound is featured on the α1-Adrenoceptors, α2-Adrenoceptors and Melatonin Receptors pages of the Handbook of Receptor Classification and Signal Transduction. To browse other handbook pages, click here.

This compound was developed by Pfizer. To browse the list of other pharma-developed compounds and Approved Drugs/Drug Candidates, click here.


Bottomless glass bottle. Contents are inside inserted fused cone.


Hygroscopic; light sensitive.

Legal Information

LOPAC is a registered trademark of Sigma-Aldrich Co. LLC

Safety & Documentation

Safety Information

Signal word 
Hazard statements 
Target organs 
Respiratory system
Personal Protective Equipment 
NONH for all modes of transport
WGK Germany 
Flash Point(F) 
Not applicable
Flash Point(C) 
Not applicable


Certificate of Analysis (COA)

Please Enter a Lot Number

Certificate of Origin (COO)

Please Enter a Lot Number
Protocols & Articles


Alpha 1 Adrenoceptor Modulators

α1-Adrenoceptors are widely distributed, and are activated either by norepinephrine released from sympathetic nerve terminals or by epinephrine released from the adrenal medulla. Receptor activation ...
Keywords: Apoptosis, Atomic absorption spectroscopy, Gene expression, Gluconeogenesis, Transduction

Alpha 2 Adrenoreceptor Modulators

α2-Adrenoceptors are widely distributed and are activated by norepinephrine (A7257, A0937), released from sympathetic nerve terminals or by epinephrine (E4250, E4375), released from the adrenal medul...
Keywords: Analgesics, Atomic absorption spectroscopy, Cardiovascular, Eliminations, Gene expression, Genetic, Neurotransmission, Neurotransmitters, Transduction

Antihypertensive Agents

Agents that inhibit angiontensin-converting enzymes (ACE) and angiotensin II formation are essential to cardiovascular medicine.1 These inhibitors are used not only to treat essential hypertension an...
Sami Barghshoon
BioFiles v7 n5, 2012, 5–20
Keywords: AGE, Antihypertensives, Cardiovascular, Clinical, Diuretics, PAGE, Reductions

Discover Bioactive Small Molecules for ADME/Tox

A significant number of drugs that fail in clinical trials have been associated with safety issues, including unexpected drug-drug interactions (DDI) or lack of efficacy due to poor pharmacokinetics....
Keywords: Absorption, Bioactive small molecules, Clinical, Metabolism

Discover Bioactive Small Molecules for Neuroscience

The nervous system, comprised of the brain and spinal cord (central nervous system, or CNS) and network of nerves that connects the CNS to the rest of the body (peripheral nervous system, or PNS) is ...
Keywords: Bioactive small molecules, Central Nervous System, Diseases, Metabolism, Neurodegenerative Diseases, Neuroscience, Neurotransmission, Neurotransmitters

Peer-Reviewed Papers


Related Products

Technical Service:

Our team of scientists has experience in all areas of research including Life Science, Material Science, Chemical Synthesis, Chromatography, Analytical and many others.

Bulk Ordering & Pricing:

Need larger quantities for your development, manufacturing or research applications?