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Efaroxan Synthesis
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)oxirane-2-carboxylateCID:100942311(3). A catalytic hydrogenation over Pd/C would give ethyl 2- 2-fluorophenyl)methyl2-hydroxybutanoateCID:77591056(4). Saponification of the ester then gives 2- 2-Fluorophenyl)methyl2-hydroxybutanoic acidCID:53869347(5). Treatment with 2 molar equivalents of sodium hydride apparently gives 2-Ethyl-2,3-dihydrobenzofuran-2-carboxylic acid 11080-50-3(6). Treatment of the carboxylic acid with thionyl chloride then gives the acid chloride and subsequent treatment of this with ethylenediamine in the presence of trimethylaluminium completed the synthesis of ' (8). See also * Fluparoxan * Idazoxan Idazoxan (INN) is a drug which is used in scientific research. It acts as both a selective α2-adrenergic receptor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha-2 Adrenergic Receptor
The alpha-2 (α2) adrenergic receptor (or adrenoceptor) is a G protein-coupled receptor (GPCR) associated with the Gi alpha subunit, Gi heterotrimeric G-protein. It consists of three highly homologous subtypes, including α2A-adrenergic, α2A-, α2B-adrenergic, α2B-, and α2C-adrenergic, α2C-adrenergic. Some species other than humans express a fourth α2D-adrenergic receptor as well. Catecholamines like norepinephrine (noradrenaline) and epinephrine (adrenaline) signal through the α2-adrenergic receptor in the central nervous system, central and peripheral nervous systems. Cellular localization The Alpha-2A adrenergic receptor, α2A adrenergic receptor is localised in the following central nervous system (CNS) structures: * Brainstem (especially the locus coeruleus as presynaptic & somatodendritic autoreceptor ) * Midbrain * Hypothalamus * Olfactory system * Hippocampus * Spinal cord * Cerebral cortex * Cerebellum * Septum Whereas the Alpha-2B adrenergic receptor, α2B adren ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Receptor Antagonist
A receptor antagonist is a type of receptor ligand or drug that blocks or dampens a biological response by binding to and blocking a receptor rather than activating it like an agonist. Antagonist drugs interfere in the natural operation of receptor proteins.Pharmacology Guide: In vitro pharmacology: concentration-response curves ." '' GlaxoWellcome.'' Retrieved on December 6, 2007. They are sometimes called blockers; examples include alpha blockers, beta b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 yet uncertain functions but is implicated in several psychiatric conditions, and I3 regulates insulin secretion. Classes As of 2017, there are three known subtypes of imidazoline receptors: I1, I2, and I3. I1 receptor The I1 receptor appears to be a G protein-coupled receptor that is localized on the plasma membrane. It may be coupled to PLA2 signalling and thus prostaglandin synthesis. In addition, activation inhibits the sodium-hydrogen antiporter and enzymes of catecholamine synthesis are induced, suggesting that the I1 receptor may belong to the neurocytokine receptor family, since its signaling pathways are similar to those of interleukins. It is found in the neurons of the reticular formation, the dorsomedial medulla oblo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Efaroxan Synthesis
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)oxirane-2-carboxylateCID:100942311(3). A catalytic hydrogenation over Pd/C would give ethyl 2- 2-fluorophenyl)methyl2-hydroxybutanoateCID:77591056(4). Saponification of the ester then gives 2- 2-Fluorophenyl)methyl2-hydroxybutanoic acidCID:53869347(5). Treatment with 2 molar equivalents of sodium hydride apparently gives 2-Ethyl-2,3-dihydrobenzofuran-2-carboxylic acid 11080-50-3(6). Treatment of the carboxylic acid with thionyl chloride then gives the acid chloride and subsequent treatment of this with ethylenediamine in the presence of trimethylaluminium completed the synthesis of ' (8). See also * Fluparoxan * Idazoxan Idazoxan (INN) is a drug which is used in scientific research. It acts as both a selective α2-adrenergic receptor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Darzens Reaction
The Darzens reaction (also known as the Darzens condensation or glycidic ester condensation) is the chemical reaction of a ketone or aldehyde with an α-haloester in the presence of a base to form an α,β-epoxy ester, also called a "glycidic ester". This reaction was discovered by the organic chemist Auguste Georges Darzens in 1904. : Reaction mechanism The reaction process begins with deprotonation at the halogenated position. Because of the ester substituents, this carbanion is a resonance-stabilized enolate. This nucleophile next attacks the carbonyl reagent, forming a carbon–carbon bond. These two steps are similar to a base-catalyzed aldol reaction. The oxygen anion in this aldol-like product then SN2 attacks on the formerly-nucleophilic halide-bearing position, displacing the halide to form an epoxide. This reaction sequence is thus a condensation reaction since there is a net loss of HCl when the two reactant molecules join. If the starting halide is an α-halo a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saponification
Saponification is a process of cleaving esters into carboxylate salts and Alcohol (chemistry), alcohols by the action of aqueous alkali. Typically aqueous sodium hydroxide solutions are used. It is an important type of alkaline hydrolysis. When the carboxylate is long chain, its salt is called a soap. The saponification of ethyl acetate gives sodium acetate and ethanol: : Saponification of fats Vegetable oils and animal fats are the traditional materials that are saponified. These greasy materials, triesters called triglycerides, are usually mixtures derived from diverse fatty acids. In the traditional saponification, the triglyceride is treated with lye, which cleaves the ester bonds, releasing fatty acid salts (soaps) and glycerol. In one simplified version, the saponification of stearin gives sodium stearate. : This process is the main industrial method for producing glycerol (). Some soap-makers leave the glycerol in the soap. Others precipitation (chemistry), precipitate t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Hydride
Sodium hydride is the chemical compound with the empirical formula Na H. This alkali metal hydride is primarily used as a strong yet combustible base in organic synthesis. NaH is a saline (salt-like) hydride, composed of Na+ and H− ions, in contrast to molecular hydrides such as borane, silane, germane, ammonia, and methane. It is an ionic material that is insoluble in all solvents (other than molten sodium metal), consistent with the fact that H− ions do not exist in solution. Basic properties and structure NaH is colorless, although samples generally appear grey. NaH is around 40% denser than Na (0.968 g/cm3). NaH, like LiH, KH, RbH, and CsH, adopts the NaCl crystal structure. In this motif, each Na+ ion is surrounded by six H− centers in an octahedral geometry. The ionic radii of H− (146 pm in NaH) and F− (133 pm) are comparable, as judged by the Na−H and Na−F distances. "Inverse sodium hydride" (hydrogen sodide) A very unusual situation occurs in a com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thionyl Chloride
Thionyl chloride is an inorganic compound with the chemical formula . It is a moderately Volatility (chemistry), volatile, colourless liquid with an unpleasant acrid odour. Thionyl chloride is primarily used as a Halogenation, chlorinating reagent, with approximately per year being produced during the early 1990s, but is occasionally also used as a solvent. It is toxic, reacts with water, and is also List of Schedule 3 substances (CWC), listed under the Chemical Weapons Convention as it may be used for the production of chemical weapons. Thionyl chloride is sometimes confused with sulfuryl chloride, , but the properties of these compounds differ significantly. Sulfuryl chloride is a source of chlorine whereas thionyl chloride is a source of chloride ions. Production The major industrial synthesis involves the reaction of sulfur trioxide and sulfur dichloride. This synthesis can be adapted to the laboratory by heating oleum to slowly distill the sulfur trioxide into a cooled fla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 500,000 tonnes produced in 1998. Ethylenediamine is the first member of the so-called polyethylene amines. Synthesis Ethylenediamine is produced industrially by treating 1,2-dichloroethane with ammonia under pressure at 180 °C in an aqueous medium (EDC process): : In this reaction hydrogen chloride is generated, which forms a salt with the amine. The amine is liberated by addition of sodium hydroxide and can then be recovered by fractional distillation. Diethylenetriamine (DETA) and triethylenetetramine (TETA) are formed as by-products. Another industrial route to ethylenediamine involves the reaction of ethanolamine and ammonia:Hans-Jürgen Arpe, Industrielle Organische Chemie, 6. Auflage (2007), Seite 275, Wiley VCH : Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluparoxan
Fluparoxan (developmental code name GR50360A) is a potent alpha-2 adrenergic receptor, α2-adrenergic receptor receptor antagonist, antagonist (pKB = 7.9) with excellent binding selectivity, selectivity for this receptor over the alpha-1 adrenergic receptor, α1-adrenergic receptor (2,630-fold), and is the only well-studied α2-adrenergic receptor antagonist in its structural family which does not antagonize any variant of the imidazoline receptor. It was shown to possess central α2-adrenoceptor antagonist activity after oral doses in man and was patented as an antidepressant by Glaxo in the early 1980s, but its development was discontinued when the compound failed to show a clear clinical advantage over existing therapies. Pharmacology Pharmacodynamics Fluparoxan is a very selective α2-adrenergic blocker, that readily crosses the blood–brain barrier. Blockade of α2-adrenoreceptors, particularly presynaptic autoreceptors in noradrenergic neurons by fluparoxan, produces an in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Idazoxan
Idazoxan (INN) is a drug which is used in scientific research. It acts as both a selective α2-adrenergic receptor antagonist, and an antagonist for the imidazoline receptor. Idazoxan has been under investigation as an antidepressant, but it did not reach the market as such. More recently, it is under investigation as an adjunctive treatment in schizophrenia. Due to its α2 receptor antagonism, it is capable of enhancing therapeutic effects of antipsychotics, possibly by enhancing dopamine neurotransmission in the prefrontal cortex of the brain, a brain area thought to be involved in the pathogenesis of schizophrenia. Research Alzheimer’s disease Mice treated with idazoxan, which blocks the α2A-adrenergic receptor, 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 disease pathology and symptoms in two mouse models, potentially offering an immediate treatment ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
