Thiosarin, sulfursarin or GBS, is the organophosphorus compound with the formula . It is closely related to sarin ().U.S. Chemical Warfare Policy: Hearings, Ninety-third Congress, Second Session. May 1, 2, 7, 9 and 14, 1974. pg 341-344 It is an extremely toxic substance related to G-agents.Ledgard, J. A Laboratory History of Chemical Warfare Agents.171-174
Characteristics Thiosarin belongs to the group of methylphosphonofluoridothioate nerve agents, comparatively less toxic than the standard G series.Augerson, W. S. Review of the Scientific Literature as it Pertains to Gulf War Illnesses. Volume 5. Chemical and Biological Warfare Agents. p 200 It is reported as a colorless liquid with a characteristic organosulfur odor when pure. It is estimated to have a boiling point of 144-167 °C. It is a more nonpolar compound, with a solubility in water of 7 g/L. Thiosarin probably belongs to the IVA compound series, leaving it much less volatile than sarin. It has a greater persistence in the environment than sarin.
Absorption frequencies of sarin derivatives showed that the frequency of stretching of the P-F and P=S bond of thiosarin is lower than that of its oxygenated analogue.
CW history and candidate Its toxicity was discovered in the 1970s by Friedrick Wilhelm Hoffmann and Ray King Irino. They were responsible for synthesizing and analyzing a series of sulfur G-agent compounds.Hoffmann et al. US 4,012,465 The open literature reports that the compound has been cataloged as GS, but this statement is incorrect, it belongs to EA-1246. GBS is generally inferior than sarin. The little open military literature may be due to the low toxicity of this series of compounds and its high aquatic and environmental persistence.
The possibility of a chemical warfare agent candidate was raised when Bogomazov and his colleagues discovered that thiosarin had the ability to break through military gas mask filters, where it would then be converted to its analogue. An investigation by Vil Mirzayanov refuted these results.
Thiosarin has been investigated as a chemical warfare agent by Iraq.INVISIBLE WEAPONS - History Of The Development And Use Of Non-Lethal Chemical Weapons. Nerve Agents: Intermediate Volatility Agent (IVA).
Thiosarin is used as a precursor to sarin.
Synthesis The preparation route is quite similar to that of sarin. The synthesis routes of thiosarin are manifold.
Regardless of the synthesis route chosen, the final reaction is usually the reaction of isopropyl methylthiophosphonochloridate with fluorides.
Reactions Thiosarin has a tendency to convert to the all oxygen analogue by divers mechanisms..Senkbeil et al. US 3,337,658 In anhydrous medium, thiosarin is oxidized to form GB.
In the controlated aqueous medium, without the presence of oxygen, the tendency is to evolve hydrogen sulfide.
Sarin-S Along with the discovery of the high toxicity of this series of compounds, Hoffmann discovered that the S-alkyl isomers, unlike the alkyl alkylphosphonothiol compounds, were less toxic than the G(S) agents and less persistent than classic G-agents.
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