A-234 (nerve agent)

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
A-234 (according to Mirzayanov)
Chemical structure of A-234 according to Mirzayanov
IUPAC name
ethyl N-[(1E)-1-(diethylamino)ethylidene]-phosphoramidofluoridate
Other names
3D model (JSmol)
Molar mass 224.216 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

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.[1][2][3][4] 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.[5] Vladimir Uglev, one of the inventors of the Novichok series of compounds, said he was "99 per cent sure that it was A-234" in relation to the 2018 Amesbury poisonings, noting its unusually high persistence in the environment.[6]

According to a classified (secret) report by the US Army National Ground Intelligence Center in Military Intelligence Digest dated 24 January 1997,[7] the agent designated as A-232 and its ethyl analog A-234, developed under the Foliant program, "are as toxic as VX, as resistant to treatment as soman, and more difficult to detect and easier to manufacture than VX". Of the agent's binary versions, one is reportedly formed by acetonitrile and an organic phosphate "that can be disguised as a pesticide precursor," while for another, Bill Gertz wrote, "soldiers need only add alcohol".

Alternative structure[edit]

A-234 (according to Hoenig)
Chemical structure of A-234 according to Hoenig
IUPAC name
([(2-chloro-1-methylpropoxy)fluorohydroxyphosphinyl]oxy)carbonimidic chloride fluoride[citation needed]
3D model (JSmol)
Molar mass 269.99 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

An alternative structure for A-234 and the related Novichok agents has been put forward by Western chemical weapons experts such as Steven Hoenig and D. Hank Ellison.[8][9] These structures are supported by Soviet literature of the time and were tested as acetylcholinesterase inhibitors,[10][11][12] however Mirzayanov claims that a number of weaker agents developed as part of the Foliant program were published in the open literature as organophosphate pesticides, in order to disguise the secret nerve agent program as legitimate pesticide research.

See also[edit]


  1. ^ Mirzayanov, Vil S. (2008). State Secrets: An Insider's Chronicle of the Russian Chemical Weapons Program. Outskirts Press. ISBN 978-1-4327-2566-2.
  2. ^ Vásárhelyi, Györgyi; Földi, László (2007). "History of Russia's chemical weapons" (PDF). AARMS. 6 (1): 135–146.[permanent dead link]
  3. ^ Halámek, E.; Kobliha, Z. (2011). "Potenciální Bojové Chemické Látky". Chemicke Listy. 105 (5): 323–333.
  4. ^ Peplow, Mark (19 March 2018). "Nerve agent attack on spy used 'Novichok' poison". Chemical & Engineering News. 96 (12): 3. Retrieved 16 March 2018.
  5. ^ Russian spy: What are Novichok agents and what do they do? BBC News, 19 March 2018
  6. ^ Novichok inventor on Amesbury poisoning: ‘I completely understand panic of those living in Salisbury’. The Independent, 6 July 2018
  7. ^ Bill Gertz. Russia dodges chemical arms ban. The Washington Times, 4 February 1997
  8. ^ Hoenig, Steven L. (2007), Compendium of Chemical Warfare Agents, Springer, ISBN 978-0-387-34626-7
  9. ^ Ellison, D. Hank (2008), Handbook of Chemical and Biological Warfare Agents (Second ed.), CRC Press, ISBN 978-0-849-31434-6
  10. ^ Kruglyak, Yu. L.; Malekin, S. I.; Martynov, I. V. (1972). "Phosphorylated oximes. XII. Reactions of 2-halophospholanes with dichlorofluoronitrosomethane". Zhurnal Obshchei Khimii. 42 (4): 811–14.
  11. ^ Raevskii, O. A.; Chapysheva, N. V.; Ivanov, A. N.; Sokolov, V. B.; Martynov, I. V. (1987). "Effect of Alkyl Substituents in Phosphorylated Oximes". Zhurnal Obshchei Khimii. 57 (12): 2720–2723.
  12. ^ Raevskii, O. A.; Grigor'ev, V. Yu.; Solov'ev, V. P.; Ivanov, A. N.; Sokolov, V. B.; Martynov, I. V. (1987). "Electron-Donor Functions of Ethyl Methylchloroformimino Methylphosphonate". Zhurnal Obshchei Khimii. 57 (9): 2073–2078.