Potential acetylcholinesterase reactivators: oxime and amidoxime derivatives.

Out of 12 oximes and amidoximes (3 of which were new to the literature) the following showed a distinct antilethal effect in DFP poisoning: RA14 (1-methylbenzimidazole-2-aldoxime methiodide), RA14 (pyridine-4-aldoxime dodecyl bromide), and RA24 (pyridine-2-aldoxime dodecyl bromide). These compounds also reactivated acetylcholinesterase (AChE) in vitro, but had no effect on this enzyme in vivo. Moreover, addition of the dodecyl chain to pyridinealdoxtimes, or in a less degree replacement of the pyridine ring with benzimidazole in aldoximes, distinctly increased acute toxicity and lipophilicity when compared with the parent pyridine compounds, along with protective action in DFP poisoning.