With the aim of reducing side effects of acetylcholinesterase inhibitors (AChEIs) during symptomatic treatment of Alzheimer’s disease, we report herein a new class of donepezil-based “bio-oxidizable” prodrugs 1 designed to be converted into dual binding site AChEIs 2. While most of indanone-derived N-benzylpyridinium salts 2 revealed to be highly potent dual binding site hAChEIs (IC₅₀ up to 3 nM), outperforming the standard drug donepezil (IC₅₀ = 11 nM), most of the corresponding 1,4-dihydropyridines 1 were found to be inactive. Promisingly, whereas the selected prodrug 1r showed good permeability in the PAMPA-BBB model and high in vitro antioxidant activity, its conversion to AChEI 2r could be easily achieved under mild conditions when incubated in various oxidizing media. Lastly, both compounds 1r and 2r did not show genotoxicity in vitro and displayed high LD₅₀ values in mice, making this prodrug 1r/drug 2r couple a good candidate for further in vivo biological experiments.

中文翻译：

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基于“生物可氧化”前药策略的基于多奈哌齐的中央乙酰胆碱酯酶抑制剂：设计，合成和体外生物学评估

为了减少对症治疗阿尔茨海默氏病期间乙酰胆碱酯酶抑制剂（AChEIs）的副作用，我们在此报告了一种新型的基于多奈哌齐的“生物可氧化”前药1，旨在将其转变为双结合位点AChEIs 2。茚满酮衍生的N-苄基吡啶鎓盐2揭示具有高度有效的双重结合位点hAChEI（IC ₅₀高达3 nM），优于标准药物多奈哌齐（IC ₅₀ = 11 nM），大多数相应的1,4-二氢吡啶1被发现处于非活动状态。很有希望，而所选的前药1r在PAMPA-BBB模型中显示出良好的渗透性，并具有很高的体外抗氧化活性，在温和条件下，在各种氧化介质中孵育时，可以轻松实现向AChEI 2r的转化。最后，化合物1r和2r在体外均未显示出遗传毒性，并且在小鼠中显示出较高的LD ₅₀值，这使该前药1r /药物2r成为了进一步体内生物学实验的良好候选者。