Sesquimustard (military code Q) is the
organosulfur compound
Organosulfur compounds are organic compounds that contain sulfur. They are often associated with foul odors, but many of the sweetest compounds known are organosulfur derivatives, e.g., saccharin. Nature abounds with organosulfur compounds—sulfu ...
with the formula . Although it is a colorless solid, impure samples are often brown. The compound is a type of
mustard gas
Mustard gas or sulfur mustard is a chemical compound belonging to a family of cytotoxic and blister agents known as mustard agents. The name ''mustard gas'' is technically incorrect: the substance, when dispersed, is often not actually a gas, b ...
, a
vesicant
A blister agent (or vesicant), is a chemical compound that causes severe skin, eye and mucosal pain and irritation. They are named for their ability to cause severe chemical burns, resulting in painful water blisters on the bodies of those affec ...
used as a
chemical weapon
A chemical weapon (CW) is a specialized munition that uses chemicals formulated to inflict death or harm on humans. According to the Organisation for the Prohibition of Chemical Weapons (OPCW), this can be any chemical compound intended as a ...
. From the chemical perspective, the compound is both a
thioether
In organic chemistry, an organic sulfide (British English sulphide) or thioether is an organosulfur functional group with the connectivity as shown on right. Like many other sulfur-containing compounds, volatile sulfides have foul odors. A sul ...
and an
alkyl chloride
An organochloride, organochlorine compound, chlorocarbon, or chlorinated hydrocarbon is an organic compound containing at least one covalently bonded atom of chlorine. The chloroalkane class (alkanes with one or more hydrogens substituted by chlor ...
.
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
Phosgene is the organic chemical compound with the formula COCl2. It is a toxic, colorless gas; in low concentrations, its musty odor resembles that of freshly cut hay or grass. Phosgene is a valued and important industrial building block, espe ...
, or as a solution. Since 1997, it has been listed under
Schedule I of the
Chemical Weapons Convention
The Chemical Weapons Convention (CWC), officially the Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons and on their Destruction, is an arms control treaty administered by the Organisation for ...
, as a substance with few uses outside of chemical warfare (although since then, it has been found to be useful in
chemotherapy
Chemotherapy (often abbreviated to chemo and sometimes CTX or CTx) is a type of cancer treatment that uses one or more anti-cancer drugs (chemotherapeutic agents or alkylating agents) as part of a standardized chemotherapy regimen. Chemotherap ...
).
See also
*
Half mustard
*
HN3 (nitrogen mustard)
Tris(2-chloroethyl)amine is the organic compound with the formula N(CH2CH2Cl)3. Often abbreviated HN3 or HN-3, it is a powerful blister agent and a nitrogen mustard used for chemical warfare. HN3 was the last of the nitrogen mustard agents develop ...
*
O-Mustard
O-Mustard (T) is a vesicant chemical weapon, a type of mustard gas, with around 3 times the toxicity of the original sulfur mustard. It was developed in England in the 1930s as a thickener for mustard gas to make it more persistent when used in wa ...
*
Selenium mustard
Bis(2-chloroethyl)selenide is the organoselenium compound with the formula . As a haloalkyl derivative of selenium, it is an analogue of bis(2-chloroethyl)sulfide, the prototypical sulfur mustard used in chemical warfare. Bis(2-chloroethyl)selenid ...
References
Sulfur mustards
Blister agents
Chloroethyl compounds
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