Idazoxan (
INN
Inns are generally establishments or buildings where travelers can seek lodging, and usually, food and drink. Inns are typically located in the country or along a highway; before the advent of motorized transportation they also provided accommo ...
) is a
drug
A drug is any chemical substance that causes a change in an organism's physiology or psychology when consumed. Drugs are typically distinguished from food and substances that provide nutritional support. Consumption of drugs can be via insuffla ...
which is used in
scientific research
The scientific method is an empirical method for acquiring knowledge that has characterized the development of science since at least the 17th century (with notable practitioners in previous centuries; see the article history of scientific m ...
. It acts as both a selective
α2 adrenergic receptor
The adrenergic receptors or adrenoceptors are a class of G protein-coupled receptors that are targets of many catecholamines like norepinephrine (noradrenaline) and epinephrine (adrenaline) produced by the body, but also many medications like beta ...
antagonist
An antagonist is a character in a story who is presented as the chief foe of the protagonist.
Etymology
The English word antagonist comes from the Greek ἀνταγωνιστής – ''antagonistēs'', "opponent, competitor, villain, enemy, riv ...
, and an antagonist for the
imidazoline receptor Imidazoline receptors are the primary receptors on which clonidine and other imidazolines act. There are three main classes of imidazoline receptor: I1 is involved in inhibition of the sympathetic nervous system to lower blood pressure, I2 has as ye ...
. Idazoxan has been under investigation as an
antidepressant
Antidepressants are a class of medication used to treat major depressive disorder, anxiety disorders, chronic pain conditions, and to help manage addictions. Common side-effects of antidepressants include dry mouth, weight gain, dizziness, hea ...
, but it did not reach the market as such. More recently, it is under investigation as an adjunctive treatment in
schizophrenia
Schizophrenia is a mental disorder characterized by continuous or relapsing episodes of psychosis. Major symptoms include hallucinations (typically hearing voices), delusions, and disorganized thinking. Other symptoms include social withdra ...
. Due to its alpha-2 receptor antagonism it is capable of enhancing therapeutic effects of
antipsychotics
Antipsychotics, also known as neuroleptics, are a class of Psychiatric medication, psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), principally in schizophrenia but ...
, possibly by enhancing
dopamine
Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic compound, organic chemical of the catecholamine and phenethylamine families. Dopamine const ...
neurotransmission
Neurotransmission (Latin: ''transmissio'' "passage, crossing" from ''transmittere'' "send, let through") is the process by which signaling molecules called neurotransmitters are released by the axon terminal of a neuron (the presynaptic neuron), ...
in the
prefrontal cortex
In mammalian brain anatomy, the prefrontal cortex (PFC) covers the front part of the frontal lobe of the cerebral cortex. The PFC contains the Brodmann areas BA8, BA9, BA10, BA11, BA12, BA13, BA14, BA24, BA25, BA32, BA44, BA45, BA46, ...
of the brain, a brain area thought to be involved in the
pathogenesis
Pathogenesis is the process by which a disease or disorder develops. It can include factors which contribute not only to the onset of the disease or disorder, but also to its progression and maintenance. The word comes from Greek πάθος ''pat ...
of schizophrenia.
Alzheimer's research
Mice treated with idazoxan, which blocks the
α2A receptor which regulates
norepinephrine
Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic chemical in the catecholamine family that functions in the brain and body as both a hormone and neurotransmitter. The name "noradrenaline" (from Latin '' ad'', ...
, behaved similarly to control animals despite still having amyloid-beta plaques in the brain, as a proof-of-concept experiment that dramatically reduced
Alzheimer's
Alzheimer's disease (AD) is a neurodegenerative disease that usually starts slowly and progressively worsens. It is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As t ...
pathology and symptoms in two mouse models, potentially offering an immediate treatment for this devastating disease.
Synthesis
Note that the literature method claims that the old original patented procedure gives a different reaction product formed through a rearrangement.
![Idazoxan synthesis](https://upload.wikimedia.org/wikipedia/commons/7/76/Idazoxan_synthesis.svg)
The reaction of catechol (1) with 2-Chloroacrylonitrile
20-37-6(2) gives 2-cyano-1,4-benzodioxan
008-92-0(3).
Pinner reaction
The Pinner reaction refers to the acid catalysed reaction of a nitrile with an alcohol to form an imino ester salt (alkyl imidate salt); this is sometimes referred to as a Pinner salt.
The reaction is named after Adolf Pinner, who first described ...
with alcoholic hydrogen chloride leads to the iminoether,
(4). Treatment with
ethylenediamine
Ethylenediamine (abbreviated as en when a ligand) is the organic compound with the formula C2H4(NH2)2. This colorless liquid with an ammonia-like odor is a basic amine. It is a widely used building block in chemical synthesis, with approximately ...
07-15-3(5) gives the imidazoline ring affording ' (6).
See also
*
Imiloxan
Imiloxan is a drug which is used in scientific research. It acts as a selective antagonist for the α2B adrenergic receptor, and has been useful for distinguishing the actions of the different α2 adrenergic subtypes.
Synthesis
The imidazole
...
*
Efaroxan
Efaroxan is an α2-adrenergic receptor antagonist and antagonist of the imidazoline receptor. Synthesis
The Darzens reaction between 2-fluorobenzaldehyde 7848-46-1(1) and Ethyl 2-bromobutyrate 33-68-6(2) gives ethyl 2-ethyl-3-(2-fluorophenyl ...
*
Fluparoxan
Fluparoxan (developmental code name GR50360A) is a potent α2-adrenergic receptor antagonist (pKB = 7.9) with excellent selectivity for this receptor over the α1-adrenergic receptor (2,630-fold), and is the only well-studied α2-adrenergic rec ...
References
Alpha blockers
Imidazoline antagonists
Benzodioxans
Imidazolines
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