sesquimustard

{{Chembox

| Name = Sesquimustard

| ImageFile = Sesquimustard.svg

| ImageSize = 250px

| ImageFile1 = Sesquimustard-3D-vdW.png

| ImageSize1 = 250px

| PIN = 1,2-Bis[(2-chloroethyl)sulfanyl]ethane

| OtherNames = Agent Q
TL-86
One-and-one-half mustard

| Section1 = {{Chembox Identifiers

| CASNo = 3563-36-8

| CASNo_Ref = {{Cascite|correct|CAS}}

| ChemSpiderID = 18025

| PubChem = 19092

| UNII = 5Y1NV229PO

| SMILES = C(CSCCCl)SCCCl

| StdInChI = 1S/C6H12Cl2S2/c7-1-3-9-5-6-10-4-2-8/h1-6H2

| StdInChIKey = AMGNHZVUZWILSB-UHFFFAOYSA-N

}}

| Section2 = {{Chembox Properties

| C=6|H=12|Cl=2|S=2

| Appearance = white solid (impure samples: pale brown)

| MeltingPtC = 56.5

| Solubility = Insoluble, slowly degrades

| SolubleOther = Alcohols, hydrocarbons, lipids, ethers, THF

}}

| Section3 = {{Chembox Hazards

| LD50 =

}}

}}

Sesquimustard (military code Q) is the organosulfur compound with the formula {{chem2|(ClCH2CH2SCH2)2}}. Although it is a colorless solid, impure samples are often brown. The compound is a type of mustard gas, a vesicant used as a chemical weapon. From the chemical perspective, the compound is both a thioether and an alkyl chloride.

Because sesquimustard is a solid at room temperature, it is not as easily deployed as related liquid mustards. It was only ever deployed as mixtures with the original mustard, with phosgene, or as a solution. Since 1997, it has been listed under Schedule I of the Chemical Weapons Convention, as a substance with few uses outside of chemical warfare{{cite journal |last1=Vocci |first1=Frank J. |last2=Ballard |first2=Thomas A. |last3=Yevich |first3=Paul |last4=Punte |first4=Charles L. |date=1963 |title=Inhalation toxicity studies with aerosols of sesqui-mustard |journal=Toxicology and Applied Pharmacology |volume=5 |issue=6 |pages=677–684 |doi=10.1016/0041-008X(63)90061-9 |pmid=14082474 |s2cid=2261517}}{{cite journal |last1=Gupta |first1=A.K. |last2=Dubey |first2=D.K. |last3=Kaushik |first3=M.P. |date=2007 |title=A simple and economical chemical neutralization method for the destruction of sulfur mustard and its analogues |journal=Journal of Hazardous Materials |volume=139 |issue=1 |pages=154–159 |doi=10.1016/j.jhazmat.2006.06.016 |pmid=16846683 |bibcode=2007JHzM..139..154G |s2cid=36625534}}{{cite journal |last1=Blum |first1=Marc-Michael |last2=Richter |first2=Annika |last3=Siegert |first3=Markus |last4=Thiermann |first4=Horst |last5=John |first5=Harald |date=2020 |title=Adduct of the blistering warfare agent sesquimustard with human serum albumin and its mass spectrometric identification for biomedical verification of exposure |journal=Analytical and Bioanalytical Chemistry |volume=412 |issue=28 |pages=7723–7737 |doi=10.1007/s00216-020-02917-w |doi-access=free |pmc=7550388 |pmid=32902690 |s2cid=221542205 |s2cid-access=free}} (although since then, it has been found to be useful in chemotherapy).{{cite journal |last1=Smith |first1=Susan L. |title=War! What is it good for? Mustard gas medicine |journal=CMAJ |date=27 February 2017 |volume=189 |issue=8 |pages=E321–E322 |doi=10.1503/cmaj.161032 |pmid=28246228 |pmc=5325736 }}