Nerve agents, sometimes also called nerve gases, are a class of organic chemicals that disrupt the mechanisms by which nerves transfer messages to organs. The disruption is caused by the blocking of acetylcholinesterase (AChE), an enzyme that catalyzes the breakdown of acetylcholine, a neurotransmitter. Nerve agents are irreversible acetylcholinesterase inhibitors used as poison.
Tabun or GA is an extremely toxic synthetic organophosphorus compound. It is a clear, colorless, and tasteless liquid with a faint fruity odor. It is classified as a nerve agent because it can fatally interfere with normal functioning of the mammalian nervous system. Its production is strictly controlled and stockpiling outlawed by the Chemical Weapons Convention of 1993. Tabun is the first of the G-series nerve agents along with GB (sarin), GD (soman) and GF (cyclosarin).
Soman is an extremely toxic chemical substance. It is a nerve agent, interfering with normal functioning of the mammalian nervous system by inhibiting the enzyme cholinesterase. It is an inhibitor of both acetylcholinesterase and butyrylcholinesterase. As a chemical weapon, it is classified as a weapon of mass destruction by the United Nations according to UN Resolution 687. Its production is strictly controlled, and stockpiling is outlawed by the Chemical Weapons Convention of 1993 where it is classified as a Schedule 1 substance. Soman was the third of the so-called G-series nerve agents to be discovered along with GA (tabun), GB (sarin), and GF (cyclosarin).
Alkylation is a chemical reaction that entails transfer of an alkyl group. The alkyl group may be transferred as an alkyl carbocation, a free radical, a carbanion, or a carbene. Alkylating agents are reagents for effecting alkylation. Alkyl groups can also be removed in a process known as dealkylation. Alkylating agents are often classified according to their nucleophilic or electrophilic character. In oil refining contexts, alkylation refers to a particular alkylation of isobutane with olefins. For upgrading of petroleum, alkylation produces a premium blending stock for gasoline. In medicine, alkylation of DNA is used in chemotherapy to damage the DNA of cancer cells. Alkylation is accomplished with the class of drugs called alkylating antineoplastic agents.
In organic chemistry, a carbamate is a category of organic compounds with the general formula R2NC(O)OR and structure >N−C(=O)−O−, which are formally derived from carbamic acid. The term includes organic compounds, formally obtained by replacing one or more of the hydrogen atoms by other organic functional groups; as well as salts with the carbamate anion H2NCOO−.
Cyclosarin or GF is an extremely toxic substance used as a chemical weapon. It is a member of the G-series family of nerve agents, a group of chemical weapons discovered and synthesized by a German team led by Gerhard Schrader. The major nerve gases are the G agents, sarin (GB), soman (GD), tabun (GA), and the V agents such as VX. The original agent, tabun, was discovered in Germany in 1936 in the process of work on organophosphorus insecticides. Next came sarin, soman and finally, cyclosarin, a product of commercial insecticide laboratories prior to World War II.
Novichok is a family of nerve agents, some of which are binary chemical weapons. The agents were developed at the GosNIIOKhT state chemical research institute by the Soviet Union and Russia between 1971 and 1993. Some Novichok agents are solids at standard temperature and pressure, while others are liquids. Dispersal of solid form agents is thought possible if in ultrafine powder state.
Organosulfur chemistry is the study of the properties and synthesis of organosulfur compounds, which 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 is abound with organosulfur compounds—sulfur is vital for life. Of the 20 common amino acids, two are organosulfur compounds, and the antibiotics penicillin and sulfa drugs both contain sulfur. While sulfur-containing antibiotics save many lives, sulfur mustard is a deadly chemical warfare agent. Fossil fuels, coal, petroleum, and natural gas, which are derived from ancient organisms, necessarily contain organosulfur compounds, the removal of which is a major focus of oil refineries.
1,3,2,4-Dithiadiphosphetane 2,4-disulfides are a class of organophosphorus, four-membered ring compounds which contain a P2S2 ring. Many of these compounds are able to act as sources of the dithiophosphine ylides; the most well known example is Lawesson's reagent.
Organoselenium chemistry is the science exploring the properties and reactivity of organoselenium compounds, chemical compounds containing carbon-to-selenium chemical bonds. Selenium belongs with oxygen and sulfur to the group 16 elements or chalcogens, and similarities in chemistry are to be expected. Organoselenium compounds are found at trace levels in ambient waters, soils and sediments.
Dimethyl methylphosphonate is an organophosphorus compound with the chemical formula CH3PO(OCH3)2. It is a colourless liquid, which is primarily used as a flame retardant.
The Barton reaction, also known as the Barton nitrite ester reaction, is a photochemical reaction that involves the photolysis of an alkyl nitrite to form a δ-nitroso alcohol.
VR is a "V-series" unitary nerve agent closely related to the better-known VX nerve agent. It became a prototype for the series of Novichok agents. According to chemical weapons expert Jonathan Tucker, the first binary formulation developed under the Soviet Foliant program was used to make Substance 33, differing from VX only in the alkyl substituents on its nitrogen and oxygen atoms. "This weapon was given the code name Novichok."
Desulfonylation reactions are chemical reactions leading to the removal of a sulfonyl group from organic compounds. As the sulfonyl functional group is electron-withdrawing, methods for cleaving the sulfur–carbon bonds of sulfones are typically reductive in nature. Olefination or replacement with hydrogen may be accomplished using reductive desulfonylation methods.
Methylphosphonyl dichloride (DC) or dichloro is an organophosphorus compound. It has a number of commercial uses but is most notable as being a precursor to several chemical weapons agents. It is a white crystalline solid that melts slightly above room temperature.
A-234 is an organophosphate nerve agent. It was developed in the Soviet Union under the FOLIANT program and is one of the group of compounds referred to as Novichok agents that were revealed by Vil Mirzayanov. In March 2018 the Russian ambassador to the UK, Alexander Yakovenko, claimed to have been informed by British authorities that A-234 had been identified as the agent used in the poisoning of Sergei and Yulia Skripal. Vladimir Uglev, one of the inventors of the Novichok series of compounds, said he was "99 percent sure that it was A-234" in relation to the 2018 Amesbury poisonings, noting its unusually high persistence in the environment.
Methylfluorophosphonylcholine (MFPCh) is an extremely toxic chemical compound related to the G-series nerve agents. It is an extremely potent acetylcholinesterase inhibitor which is around 100 times more potent than sarin at inhibiting acetylcholinesterase in vitro, and around 10 times more potent in vivo, depending on route of administration and animal species tested. MFPCh is resistant to oxime reactivators, meaning the acetylcholinesterase inhibited by MFPCh can't be reactivated by cholinesterase reactivators. MFPCh also acts directly on the acetylcholine receptors. However, despite its high toxicity, methylfluorophosphonylcholine is a relatively unstable compound and degrades rapidly in storage, so it was not deemed suitable to be weaponised for military use.
A-242 is an organophosphate nerve agent. It was developed in the Soviet Union under the FOLIANT program and is one of the group of compounds referred to as Novichok agents that were revealed by Vil Mirzayanov. Mirzayanov gives little specific information about A-242, stating that it is highly toxic but no figures are given to compare it to other related agents. It is reportedly a solid rather than a volatile liquid as with most nerve agents, and in order to weaponise it successfully, it had to be milled into a fine powder form that could be dispersed as a dust.
A-262 is an organophosphate nerve agent. It was developed in the Soviet Union under the FOLIANT program and is one of the group of compounds referred to as Novichok agents that were revealed by Vil Mirzayanov. Mirzayanov gives little specific information about A-262, stating that it is highly toxic, but no figures are given to compare it to other related agents. It is reportedly a solid rather than a volatile liquid as with most nerve agents, and in order to weaponise it successfully, it had to be milled into a fine powder form that could be dispersed as a dust.
Dimethyl trithiocarbonate is an organic compound with the chemical formula S=C(SCH3)2. It is a methyl ester of trithiocarbonic acid. This chemical belongs to a subcategory of esters called thioesters. It is a sulfur analog of dimethyl carbonate O=C(OCH3)2, where all three oxygen atoms are replaced with sulfur atoms. Dimethyl trithiocarbonate is a yellow liquid with a strong and unpleasant odor.
