Paraoxon

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Paraoxon
Paraoxon structure.svg
Paraoxon-3D-balls.png
Clinical data
ATC code
Legal status
Legal status
  • In general: uncontrolled
Identifiers
  • Diethyl 4-nitrophenyl phosphate
CAS Number
PubChem CID
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard 100.005.657 OOjs UI icon edit-ltr-progressive.svg
Chemical and physical data
Formula C10H14NO6P
Molar mass 275.197 g·mol−1
3D model (JSmol)
  • [O-][N+](=O)c1ccc(OP(=O)(OCC)OCC)cc1
  • InChI=1S/C10H14NO6P/c1-3-15-18(14,16-4-2)17-10-7-5-9(6-8-10)11(12)13/h5-8H,3-4H2,1-2H3 Yes check.svgY
  • Key:WYMSBXTXOHUIGT-UHFFFAOYSA-N Yes check.svgY
 X mark.svgNYes check.svgY  (what is this?)    (verify)

Paraoxon is a parasympathomimetic drug which acts as an cholinesterase inhibitor. It is an organophosphate oxon, and the active metabolite of the insecticide parathion. It is also used as an ophthalmological drug against glaucoma. Paraoxon is one of the most potent acetylcholinesterase-inhibiting insecticides available, around 70% as potent as the nerve agent sarin, and so is now rarely used as an insecticide due to the risk of poisoning to humans and other animals. Paraoxon has been used by scientists to study acute and chronic effects of organophosphate intoxication. [1] [2] It is easily absorbed through skin, and was allegedly used as an assassination weapon by the apartheid-era South African chemical weapons program Project Coast. [3]

See also

Related Research Articles

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<span class="mw-page-title-main">Neurotoxin</span> Toxin harmful to nervous tissue

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<span class="mw-page-title-main">Cholinesterase</span> Esterase that lyses choline-based esters

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<span class="mw-page-title-main">Malathion</span> Chemical compound

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<span class="mw-page-title-main">Organophosphate poisoning</span> Toxic effect of pesticides

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<span class="mw-page-title-main">Benzofuranylpropylaminopentane</span> Chemical compound

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<span class="mw-page-title-main">Acetylcholinesterase inhibitor</span> Drugs that inhibit acetylcholinesterase

Acetylcholinesterase inhibitors (AChEIs) also often called cholinesterase inhibitors, inhibit the enzyme acetylcholinesterase from breaking down the neurotransmitter acetylcholine into choline and acetate, thereby increasing both the level and duration of action of acetylcholine in the central nervous system, autonomic ganglia and neuromuscular junctions, which are rich in acetylcholine receptors. Acetylcholinesterase inhibitors are one of two types of cholinesterase inhibitors; the other being butyryl-cholinesterase inhibitors. Acetylcholinesterase is the primary member of the cholinesterase enzyme family.

<span class="mw-page-title-main">Cholinesterase inhibitor</span> Chemicals which prevent breakdown of acetylcholine and butyrylcholine

Cholinesterase inhibitors (ChEIs), also known as anti-cholinesterase, are chemicals that prevent the breakdown of the neurotransmitter acetylcholine or butyrylcholine. This increases the amount of the acetylcholine or butyrylcholine in the synaptic cleft that can bind to muscarinic receptors, nicotinic receptors and others. This group of inhibitors is divided into two subgroups, acetylcholinesterase inhibitors (AChEIs) and butyrylcholinesterase inhibitors (BChEIs).

<span class="mw-page-title-main">Profenofos</span> Chemical compound

Profenofos is an organophosphate insecticide. It is a liquid with a pale yellow to amber color and a garlic-like odor. It was first registered in the United States in 1982. As of 2015, it was not approved in the European Union.

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Fenpropathrin, or fenopropathrin, is a widely used pyrethroid insecticide in agriculture and household. Fenpropathrin is an ingestion and contact synthetic pyrethroid. Its mode of action is similar to other natural (pyrethrum) and synthetic pyrethroids where in they interfere with the kinetics of voltage gated sodium channels causing paralysis and death of the pest. Fenpropathrin was the first of the light-stable synthetic pyrethroids to be synthesized in 1971, but it was not commercialized until 1980. Like other pyrethroids with an α-cyano group, fenpropathrin also belongs to the termed type II pyrethroids. Type II pyrethroids are a more potent toxicant than type I in depolarizing insect nerves. Application rates of fenpropathrin in agriculture according to US environmental protection agency (EPA) varies by crop but is not to exceed 0.4 lb ai/acre.

<span class="mw-page-title-main">Guanitoxin</span> Chemical compound

Guanitoxin (GNT), formerly known as anatoxin-a(S) "Salivary", is a naturally occurring cyanotoxin commonly isolated from cyanobacteria. It is a potent covalent acetylcholinesterase inhibitor, and thus a potent rapid acting neurotoxin which in cases of severe exposure can lead to death. Guanitoxin was first structurally characterized in 1989, and consists of a cyclic N-hydroxyguanidine organophosphate with a phosphate ester moiety.

References

  1. Deshpande LS, Carter DS, Phillips KF, Blair RE, DeLorenzo RJ (September 2014). "Development of status epilepticus, sustained calcium elevations and neuronal injury in a rat survival model of lethal paraoxon intoxication". Neurotoxicology. 44: 17–26. doi:10.1016/j.neuro.2014.04.006. PMC   4176600 . PMID   24785379.
  2. Deshpande LS, Phillips K, Huang B, DeLorenzo RJ (September 2014). "Chronic behavioral and cognitive deficits in a rat survival model of paraoxon toxicity". Neurotoxicology. 44: 352–7. doi:10.1016/j.neuro.2014.08.008. PMC   4175062 . PMID   25172410.
  3. NTI Country Overviews:South Africa:Chemical Capabilities:Paraoxon Archived 2008-07-08 at the Wayback Machine