Tetroxime: reactivation potency - in vitro and in silico study

Acetylcholinesterase (AChE) reactivators (oximes) are generally used as treatment in cases of nerve agent poisoning. There is no single oxime applicable in every case of nerve agent intoxication. Based on this fact, novel candidates with broader efficacy are still being sought. In this study, tetroxime a bisquaternary compound bearing four oxime groups, was evaluated for its potency to reactivate rat brain AChE inhibited by selected nerve agents (tabun, sarin, cyclosarin and VX agent). Despite the fact that this oxime contains four oxime groups that could be plausibly responsible for reactivation, it did not achieve broader reactivation activity. Satisfactory results were obtained only in the case of VX agent-inhibited AChE. In the cases of sarin-and cyclosarin-inhibited AChE, acceptable results were reached at higher oxime concentration only. Tetroxime was unable to reactivate tabun-inhibited AChE. However, compared with the gold standard pralidoxime, this oxime achieved more promising results.