In our earlier paper, we described ferulic acid (FA) template based novel series of multifunctional cholinesterase (ChE) inhibitors for the management of AD. This report has further extended the structure-activity relationship (SAR) studies of this series of molecules in a calibrated manner to improve upon the ChEs inhibition and antioxidant property to identify the novel potent multifunctional molecule. To investigate the effect of replacement of phenylpiperazine ring with benzylpiperazine, increase in the linker length between FA and substituted phenyl ring, and replacement of indole moiety with tryptamine on this molecular template, three series of novel molecules were developed. All synthesized compounds were tested for their acetyl and butyryl cholinestrases (AChE and BChE) inhibitory properties. Enzyme inhibition and PAS binding studies identified compound 13b as a lead molecule with potent inhibitor property towards AChE/BChE (AChE IC₅₀ = 0.96 ± 0.14 µM, BChE IC₅₀ = 1.23 ± 0.23 µM) compared to earlier identified lead molecule EJMC-G (AChE IC₅₀ = 5.74 ± 0.13 μM, BChE IC₅₀ = 14.05 ± 0.10 μM, respectively). Molecular docking and dynamics studies revealed that 13b fits well into the active sites of AChE and BChE, forming stable and strong interactions with key residues Trp86, Ser125, Glu202, Trp 286, Phe295, Tyr 337 in AChE, and with Trp 82, Gly115, Tyr128, and Ser287 in BChE. The compound, 13b was found to be three times more potent antioxidant in a DPPH assay (IC₅₀ = 20.25 ± 0.26 µM) over the earlier identified EJMC-B (IC₅₀ = 61.98 ± 0.30 µM) and it also was able to chelate iron. Co-treatment of 13b with H₂O₂, significantly attenuated and reversed H₂O₂-induced toxicity in the SH-SY5Y cells. The parallel artificial membrane permeability assay-blood brain barrier (PAMPA-BBB) revealed that 13b could cross BBB efficiently. Finally, the in-vivo efficacy of 13b at doses of 5 and 10 mg/kg in scopolamine AD model has been demonstrated. The present study strongly suggests that the naturally inspired multifunctional molecule 13b may behave as a potential novel therapeutic agent for AD management.

在我们之前的论文中，我们描述了基于阿魏酸 ( FA ) 模板的新型多功能胆碱酯酶 (ChE) 抑制剂系列，用于治疗 AD。本报告以校准的方式进一步扩展了该系列分子的构效关系 (SAR) 研究，以提高对 ChE 的抑制和抗氧化性能，从而鉴定出新型强效多功能分子。研究用苄基哌嗪取代苯基哌嗪环的效果，增加FA之间的接头长度和取代苯环，并在该分子模板上用色胺取代吲哚部分，开发了三个系列的新分子。测试了所有合成化合物的乙酰胆碱酯酶和丁酰胆碱酯酶（AChE 和 BChE）抑制特性。酶抑制和PAS结合研究鉴定的化合物13B，为先导分子朝向乙酰胆碱酯酶/ BChE的强效抑制剂属性胆碱酯酶（AChE的IC ₅₀ = 0.96±0.14 μ男，IC的BChE ₅₀ = 1.23±0.23 μ M）相比，先前确定先导分子EJMC- G（AChE IC ₅₀ = 5.74 ± 0.13 μ M，BChE IC ₅₀ = 14.05 ± 0.10 μ分别为 M）。分子对接和动力学研究表明，13b与 AChE 和 BChE 的活性位点非常吻合，与 AChE 中的关键残基 Trp86、Ser125、Glu202、Trp 286、Phe295、Tyr 337 以及 Trp 82、Gly115、 BChE 中的 Tyr128 和 Ser287。在 DPPH 测定中，发现化合物13b 的抗氧化剂（IC ₅₀ = 20.25 ± 0.26 µ M）是早期鉴定的EJMC-B（IC ₅₀ = 61.98 ± 0.30 µ M）的三倍，并且它还能够螯合铁。13b与 H ₂ O ₂共同处理，显着减弱和逆转 H ₂O ₂诱导的SH-SY5Y细胞毒性。平行人工膜通透性测定-血脑屏障 (PAMPA-BBB) 表明13b可以有效穿过 BBB。最后，13b在东莨菪碱 AD 模型中以 5 和 10 mg/kg 的剂量显示了体内功效。本研究强烈表明，自然启发的多功能分子13b可能作为 AD 管理的潜在新型治疗剂。