Paraoxon

{{short description|Chemical compound}}

{{cs1 config|name-list-style=vanc|display-authors=6}}

{{Drugbox

| Verifiedfields = changed

| Watchedfields = changed

| verifiedrevid = 417767322

| IUPAC_name = Diethyl 4-nitrophenyl phosphate

| image = Paraoxon structure.svg

| image_class = skin-invert-image

| width = 200px

| image2 = Paraoxon-3D-balls.png

| width2 = 170px

| tradename =

| pregnancy_category =

| legal_status = Uncontrolled

| routes_of_administration =

| bioavailability =

| protein_bound =

| metabolism =

| elimination_half-life =

| excretion =

| CAS_number_Ref = {{cascite|correct|??}}

| CAS_number = 311-45-5

| ATC_prefix = S01

| ATC_suffix = EB10

| PubChem = 9395

| DrugBank_Ref = {{drugbankcite|correct|drugbank}}

| DrugBank =

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| ChemSpiderID = 9026

| UNII_Ref = {{fdacite|changed|FDA}}

| UNII = Q9CX8P80JW

| ChEBI_Ref = {{ebicite|changed|EBI}}

| ChEBI = 27827

| ChEMBL_Ref = {{ebicite|correct|EBI}}

| ChEMBL = 23838

| KEGG_Ref = {{keggcite|changed|kegg}}

| KEGG = D10529

| C=10 | H=14 | N=1 | O=6 | P=1

| smiles = [O-][N+](=O)c1ccc(OP(=O)(OCC)OCC)cc1

| StdInChI_Ref = {{stdinchicite|correct|chemspider}}

| StdInChI = 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

| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}

| StdInChIKey = WYMSBXTXOHUIGT-UHFFFAOYSA-N

}}

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.{{cite journal | vauthors = Deshpande LS, Carter DS, Phillips KF, Blair RE, DeLorenzo RJ | title = Development of status epilepticus, sustained calcium elevations and neuronal injury in a rat survival model of lethal paraoxon intoxication | journal = Neurotoxicology | volume = 44 | pages = 17–26 | date = September 2014 | pmid = 24785379 | pmc = 4176600 | doi = 10.1016/j.neuro.2014.04.006 | bibcode = 2014NeuTx..44...17D }}{{cite journal | vauthors = Deshpande LS, Phillips K, Huang B, DeLorenzo RJ | title = Chronic behavioral and cognitive deficits in a rat survival model of paraoxon toxicity | journal = Neurotoxicology | volume = 44 | pages = 352–7 | date = September 2014 | pmid = 25172410 | pmc = 4175062 | doi = 10.1016/j.neuro.2014.08.008 | bibcode = 2014NeuTx..44..352D }} 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.{{cite web | url = http://www.nti.org/e_research/profiles/SAfrica/Chemical/2440_3598.html | location = Washington, DC | publisher = Nuclear Threat Initiative | work = NTI Country Overviews: South Africa: Chemical Capabilities | title = Paraoxon | archive-url = https://web.archive.org/web/20080708231705/http://www.nti.org/e_research/profiles/SAfrica/Chemical/2440_3598.html | archive-date=2008-07-08 | date = March 2004 }}

EA-1370 is a phosphonate analogue, isopropyl para-nitrophenyl methylphosphonate, the junction of the nerve agent sarin with the leaving group of paraoxon.{{cite report | vauthors = Higuchi T | title = Molecular Catalysis and Interactions in Aqueous Solutions. | id = Contract No. DA 18-108-AMC-88A - Final Report. | date = 24 March 1964 | url = https://apps.dtic.mil/sti/tr/pdf/AD0437607.pdf }} Contact with the fluoride ion in a polar-aprotic solvent regenerates it to sarin.{{Cite journal | vauthors = Davis GT, Demek MM, Sowa JR, Epstein J |date=1971-08-01 |title=Solvent effects on displacement of fluoride ion from isopropyl methylphosphonofluoridate |journal=Journal of the American Chemical Society |volume=93 |issue=17 |pages=4093–4103 |doi=10.1021/ja00746a001 |bibcode=1971JAChS..93.4093D |issn=0002-7863}}{{cite journal | vauthors = Camp HB, Fukuto TR, Metcalf RL |title=Toxicity of isopropyl parathion. Effect of structure on toxicity and anticholinesterase activity |journal=Journal of Agricultural and Food Chemistry |date=March 1969 |volume=17 |issue=2 |pages=243–248 |doi=10.1021/jf60162a038 |bibcode=1969JAFC...17..243C }}