Abstract：
Organophosphorus (OP) nerve agents inhibit acetylcholinesterase (AChE), creating a cholinergic crisis in which death can occur. The phosphylated serine residue spontaneously dealkylates to the OP-aged form, which current therapeutics cannot reverse. Soman\'s aging half-life is 4.2 min, so immediate recovery (resurrection) of OP-aged AChE is needed. In 2018, we showed pyridin-3-ol-based quinone methide precursors (QMPs) can resurrect OP-aged electric eel AChE in vitro, achieving 2% resurrection after 24 h of incubation (pH 7, 4 mM). We prepared 50 unique 6-alkoxypyridin-3-ol QMPs with 10 alkoxy groups and five amine leaving groups to improve AChE resurrection. These compounds are predicted in silico to cross the blood-brain barrier and treat AChE in the central nervous system. This library resurrected 7.9% activity of OP-aged recombinant human AChE after 24 h at 250 μM, a 4-fold increase from our 2018 report. The best QMP (1b), with a 6-methoxypyridin-3-ol core and a diethylamine leaving group, recovered 20.8% (1 mM), 34% (4 mM), and 42.5% (predicted maximum) of methylphosphonate-aged AChE activity over 24 h. Seven QMPs recovered activity from AChE aged with Soman and a VX degradation product (EA-2192). We hypothesize that QMPs form the quinone methide (QM) to realkylate the phosphylated serine residue as the first step of resurrection. We calculated thermodynamic energetics for QM formation, but there was no trend with the experimental biochemical data. Molecular docking studies revealed that QMP binding to OP-aged AChE is not the determining factor for the observed biochemical trends; thus, QM formation may be enzyme-mediated.
摘要：
有机磷（OP）神经毒剂抑制乙酰胆碱酯酶（AChE），造成胆碱能危机，其中可能发生死亡。磷酸化的丝氨酸残基自发地脱烷基化为OP老化的形式，目前的疗法无法逆转。Soman的衰老半衰期为4.2分钟，因此，需要立即恢复（复活）OP年龄的AChE。在2018年，我们发现基于吡啶-3-醇的醌甲基化物前体（QMPs）可以在体外复活OP老化的电鳗鱼AChE，孵育24小时后实现2%的复活(pH7,4mM)。我们制备了50种具有10个烷氧基和5个胺离去基团的独特的6-烷氧基吡啶-3-醇QMPs，以改善AChE的复活。预测这些化合物在电脑中穿过血脑屏障并治疗中枢神经系统中的AChE。该文库在250μM下24小时后复活了7.9％的OP老化的重组人AChE活性，比我们的2018年报告增加了4倍。最好的QMP（1b），具有6-甲氧基吡啶-3-醇核心和二乙胺离去基团，恢复20.8%(1mM)，34%（4mM），和42.5%(预测的最大值)甲基膦酸酯老化的AChE活性超过24小时。七个QMP从用Soman和VX降解产物(EA-2192)老化的AChE中恢复活性。我们假设QMPs形成醌甲基化物（QM）以重新烷基化磷酸化的丝氨酸残基，这是复活的第一步。我们计算了QM形成的热力学能量学，但是实验生化数据没有趋势。分子对接研究表明，QMP与OP老化的AChE结合并不是观察到的生化趋势的决定因素；因此，QM形成可以是酶介导的。
