View source for Allyl isothiocyanate

{{chembox
|Verifiedfields = changed
|Watchedfields = changed
|verifiedrevid = 477314225
|Name = Allyl isothiocyanate
|ImageFile = Allyl-isothiocyanate-2D-skeletal.png
|ImageSize = 200px
|ImageName = Allyl isothiocyanate
|ImageFile1 = Allyl-isothiocyanate-3D-vdW.png
|ImageSize1 = 150px
|ImageName1 = Space-filling model of allyl isothiocyanate
|PIN = 3-Isothiocyanatoprop-1-ene
|OtherNames = Synthetic mustard oil
|Section1={{Chembox Identifiers
|IUPHAR_ligand = 2420
|UNII_Ref = {{fdacite|correct|FDA}}
|UNII = BN34FX42G3
|ChEBI_Ref = {{ebicite|changed|EBI}}
|ChEBI = 73224
|KEGG_Ref = {{keggcite|correct|kegg}}
|KEGG = D02818
|KEGG1=C19317
|InChI = 1/C4H5NS/c1-2-3-5-4-6/h2H,1,3H2
|InChIKey = ZOJBYZNEUISWFT-UHFFFAOYAS
|StdInChI_Ref = {{stdinchicite|correct|chemspider}}
|StdInChI = 1S/C4H5NS/c1-2-3-5-4-6/h2H,1,3H2
|StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
|StdInChIKey = ZOJBYZNEUISWFT-UHFFFAOYSA-N
|CASNo_Ref = {{cascite|correct|CAS}}
|CASNo = 57-06-7
|ChEMBL_Ref = {{ebicite|correct|EBI}}
|ChEMBL = 233248
|ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
|ChemSpiderID = 21105854
|SMILES = C=CCN=C=S
|PubChem = 5971
|EINECS = 200-309-2
|RTECS = NX8225000
|UNNumber = 1545
}}
|Section2={{Chembox Properties
|C=4|H=5|N=1|S=1
|Density = 1.013–1.020 g/cm<sup>3</sup>
|MeltingPtC = −102
|BoilingPtC = 148 to 154
}}
|Section7={{Chembox Hazards
|GHSPictograms = {{GHS02}}{{GHS06}}{{GHS07}}{{GHS09}}
|GHSSignalWord = Danger
|HPhrases = {{H-phrases|226|301|310|315|319|330|335|410}}
|PPhrases = {{P-phrases|210|233|240|241|242|243|260|261|262|264|270|271|273|280|284|301+310|302+350|302+352|303+361+353|304+340|305+351+338|310|312|320|321|322|330|332+313|337+313|361|362|363|370+378|391|403+233|403+235|405|501}}
}}
}}

'''Allyl isothiocyanate''' ('''AITC''') is a naturally occurring unsaturated [[isothiocyanate]]. The colorless oil is responsible for the pungent taste of [[cruciferous vegetables]] such as [[mustard (condiment)|mustard]], [[radish]], [[horseradish]], and [[wasabi]]. This [[pungency]] and the [[tears|lachrymatory effect]] of AITC are mediated through the [[TRPA1]] and [[TRPV1]]  ion channels.<ref>{{cite journal | last1 = Everaerts | first1 = W. | last2 = Gees | first2 = M. | last3 = Alpizar | first3 = Y. A. | last4 = Farre | first4 = R. | last5 = Leten | first5 = C. | last6 = Apetrei | first6 = A. | last7 = Dewachter | first7 = I. | last8 = van Leuven | first8 = F. | last9 = Vennekens | first9 = R.| title = The Capsaicin Receptor TRPV1 is a Crucial Mediator of the Noxious Effects of Mustard Oil | journal = Current Biology | year = 2011 | volume = 21 | issue = 4 | pages = 316–321 | pmid = 21315593 | doi = 10.1016/j.cub.2011.01.031 | s2cid = 13151479 | doi-access = free| bibcode = 2011CBio...21..316E | hdl = 2078.1/121650 | hdl-access = free }}</ref><ref name="pmid18501939">{{cite journal |author1=Brône, B. |author2=Peeters, P. J. |author3=Marrannes, R. |author4=Mercken, M. |author5=Nuydens, R. |author6=Meert, T. |author7=Gijsen, H. J. | title = Tear gasses CN, CR, and CS are potent activators of the human TRPA1 receptor | journal = [[Toxicology and Applied Pharmacology]] | year = 2008 | volume = 231 | issue = 2 | pages = 150–156 | pmid = 18501939 | doi = 10.1016/j.taap.2008.04.005 |bibcode=2008ToxAP.231..150B }}</ref><ref name="pmid21741838">{{cite journal |author1=Ryckmans, T. |author2=Aubdool, A. A. |author3=Bodkin, J. V. |author4=Cox, P. |author5=Brain, S. D. |author6=Dupont, T. |author7=Fairman, E. |author8=Hashizume, Y. |author9=Ishii, N. | title = Design and Pharmacological Evaluation of [[PF-4840154]], a Non-Electrophilic Reference Agonist of the TrpA1 Channel | journal = Bioorganic & Medicinal Chemistry Letters | year = 2011 | volume = 21 | issue = 16 | pages = 4857–4859 | pmid = 21741838 | doi = 10.1016/j.bmcl.2011.06.035 |display-authors=etal}}</ref> It is slightly soluble in water, but more soluble in most organic solvents.<ref name=Ullmann>{{Ullmann | author = Romanowski, F. |author2=Klenk, H. | title = Thiocyanates and Isothiocyanates, Organic | doi = 10.1002/14356007.a26_749}}</ref>

==Biosynthesis and biological functions==
Allyl isothiocyanate can be obtained from the seeds of [[Rhamphospermum nigrum|black mustard]] (''Rhamphospermum nigrum'') or brown [[Brassica juncea|Indian mustard]] (''Brassica juncea''). When these [[mustard seed]]s are broken, the [[enzyme]] [[myrosinase]] is released and acts on a [[glucosinolate]] known as [[sinigrin]] to give allyl isothiocyanate.<ref name=pmid31771793>{{cite journal |doi=10.1016/j.phytochem.2019.112100 |doi-access=free |title=Glucosinolate structural diversity, identification, chemical synthesis and metabolism in plants |year=2020 |last1=Blažević |first1=Ivica |last2=Montaut |first2=Sabine |last3=Burčul |first3=Franko |last4=Olsen |first4=Carl Erik |last5=Burow |first5=Meike |last6=Rollin |first6=Patrick |last7=Agerbirk |first7=Niels |journal=Phytochemistry |volume=169 |page=112100 |pmid=31771793 |bibcode=2020PChem.169k2100B |s2cid=208318505 }}</ref>  This serves the plant as a defense against [[herbivore]]s; since it is harmful to the plant itself,<ref>{{Cite journal |last1=Li |first1=Yingbin |last2=Lu |first2=Daqing |last3=Xia |first3=Yan |last4=Xu |first4=Xinjing |last5=Huang |first5=Huichuan |last6=Mei |first6=Xinyue |last7=Yang |first7=Min |last8=Li |first8=Jianqiang |last9=Zhu |first9=Shusheng |last10=Liu |first10=Yixiang |last11=Zhang |first11=Zhiping |date=2023-09-30 |title=Effects of allyl isothiocyanate fumigation on medicinal plant root knot disease control, plant survival, and the soil bacterial community |journal=BMC Microbiology |volume=23 |issue=1 |pages=278 |doi=10.1186/s12866-023-02992-w |doi-access=free |issn=1471-2180 |pmc=10542678 |pmid=37775764 |quote=Allyl isothiocyanate (AITC) [...] has been used in agriculture because of its fungicidal [...] bactericidal, nematocidal [able to destroy nematodes], and herbicidal [able to destroy plants] biological activities. }}</ref> it is stored in the harmless form of the glucosinolate, separate from the myrosinase enzyme.  When an animal chews the plant, the allyl isothiocyanate is released, repelling the animal.  Human appreciation of the pungency is learned.<ref name=EFC>{{Cite book |editor-last=Melton |editor-first=Laurence |title=The Encyclopedia of Food Chemistry |publisher=Elsevier |year=2019 |isbn=978-0-12-814045-1 |location=Netherlands }}</ref>{{rp|105}}

The compound has been shown to strongly repel [[Red imported fire ant|fire ants]] (''Solenopsis invicta'').<ref>{{cite journal | doi = 10.1007/s13355-019-00613-5 | title = Wasabi versus red imported fire ants: Preliminary test of repellency of microencapsulated allyl isothiocyanate against Solenopsis invicta (Hymenoptera: Formicidae) using bait traps in Taiwan | date = 2019 | last1 = Hashimoto | first1 = Yoshiaki | last2 = Yoshimura | first2 = Masashi | last3 = Huang | first3 = Rong-Nan | journal = Applied Entomology and Zoology | volume = 54 | issue = 2 | pages = 193–196 | bibcode = 2019AppEZ..54..193H | url = https://oist.repo.nii.ac.jp/?action=repository_uri&item_id=1557 }}</ref>  AITC vapor is also used as an antimicrobial and shelf life extender in food packaging.<ref name=EFC/>{{rp|118–120}}

==Production and applications==
Allyl isothiocyanate is produced commercially by the reaction of [[allyl chloride]] and [[potassium thiocyanate]]:<ref name=Ullmann/>
:CH<sub>2</sub>=CHCH<sub>2</sub>Cl + KSCN → CH<sub>2</sub>=CHCH<sub>2</sub>NCS + KCl
The product obtained in this fashion is sometimes known as ''synthetic mustard oil''.  
Allyl thiocyanate isomerizes to the isothiocyanate:<ref name=JCE>{{cite journal |doi=10.1021/ed048p81 |title=The Preparation and Isomerization of Allyl Thiocyanate. An Organic Chemistry Experiment |date=1971 |last1=Emergon |first1=David W. |journal=Journal of Chemical Education |volume=48 |issue=1 |page=81 |bibcode=1971JChEd..48...81E }}</ref>
:{{chem2|CH2\dCHCH2SCN  ->  CH2\dCHCH2NCS}}
Allyl isothiocyanate can also be liberated by dry [[distillation]] of the seeds. The product obtained in this fashion is known as [[mustard oil|volatile oil of mustard]].  

It is used principally as a [[flavoring]] agent in foods.  Synthetic allyl isothiocyanate is used as an [[insecticide]], as an anti-mold agent <ref>US Patent No. 8691042</ref> <!--as an [[animal repellent]], to [[denatured alcohol|denature alcohol]], and as a [[topical anesthetic]].--> [[antibacterial|bacteriocide]],<ref>{{cite journal |last1=Masuda |first1=Shuichi |last2=Masuda |first2=Hideki |last3=Shimamura |first3=Yuko |last4=Sugiyama |first4=Chitose |last5=Takabayashi |first5=Fumiyo |title=Improvement Effects of Wasabi (Wasabia japonica) Leaves and Allyl Isothiocyanate on Stomach Lesions of Mongolian Gerbils Infected with Helicobacter pylori |journal=Natural Product Communications |date=April 2017 |volume=12 |issue=4 |pages=595–598 |doi=10.1177/1934578X1701200431 |pmid=30520603|s2cid=54567566 |doi-access=free }}</ref> and [[nematicide]], and is used in certain cases for crop protection.<ref name=Ullmann/> It is also used in fire alarms for the deaf.<ref>{{US patent reference|number= 20100308995A1|issue-date= 2015-06-24 |inventor= Hideaki Goto, Tomo Sakai, Koichiro Mizoguchi, Yukinobu Tajima, Makoto Imai| title= Odor generation alarm and method for informing unusual situation}}</ref><ref>{{cite web |last1=Phillipson |first1=Tacye |title=Why would you want a wasabai fire alarm? |url=https://blog.nms.ac.uk/2018/08/29/why-would-you-want-a-wasbai-fire-alarm/ |website=National Museums Scotland Blog |date=29 August 2018 |access-date=10 March 2022}}</ref>

Hydrolysis of allyl isothiocyanate gives [[allylamine]].<ref>{{OrgSynth | author = Leffler, M. T. | title = Allylamine | volume = 18 | pages = 5 | collvol = 2 | collvolpages = 24 | year = 1938 | prep = CV2P0024 }}</ref>

==Safety==
Allyl isothiocyanate has an [[Median lethal dose|LD<sub>50</sub>]] of 151&nbsp;mg/kg and is a [[lachrymator]] (similar to tear gas or mace).<ref name=Ullmann/>

===Oncology===
Based on ''[[in vitro]]'' experiments and [[animal model]]s, allyl isothiocyanate exhibits many of the desirable attributes of a cancer chemopreventive agent.<ref>{{Cite journal
 | pmid = 19960458
| year = 2010
| last1 = Zhang
| first1 = Y
| title = Allyl isothiocyanate as a cancer chemopreventive phytochemical
| journal = Molecular Nutrition & Food Research
| volume = 54
| issue = 1
| pages = 127–35
| doi = 10.1002/mnfr.200900323
| pmc = 2814364
}}</ref>

== See also ==
*[[Mustard plaster]], traditional home remedy
*[[Piperine]], the piquant chemical in [[black pepper]]
*[[Capsaicin]], the piquant chemical in [[chili pepper]]s
*[[Allicin]], the piquant flavor chemical in raw [[garlic]]

== References ==
{{reflist}}

{{Cruciferous Biochemistry}}
{{Transient receptor potential channel modulators}}
{{Xenobiotic-sensing receptor modulators}}

[[Category:Antibiotics]]
[[Category:Insecticides]]
[[Category:Isothiocyanates]]
[[Category:Pungent flavors]]
[[Category:Nematicides]]
[[Category:Allyl compounds]]
[[Category:Lachrymatory agents]]
[[Category:Transient receptor potential channel modulators]]