AbstractTwo libraries of quinoline‐based hybrids 1‐(7‐chloroquinolin‐4‐yl)‐1H‐pyrazolo[3,4–d]pyrimidin‐4‐amine and 7‐chloro‐N‐phenylquinolin‐4‐amine were synthesized and evaluated for their α‐glucosidase inhibitory and antioxidant properties. Compounds with 4‐methylpiperidine and para‐trifluoromethoxy groups, respectively, showed the most promising α‐glucosidase inhibition activity with IC50=46.70 and 40.84 μM, compared to the reference inhibitor, acarbose (IC50=51.73 μM). Structure‐activity relationship analysis suggested that the cyclic secondary amine pendants and para‐phenyl substituents account for the variable enzyme inhibition. Antioxidant profiling further revealed that compounds with an N‐methylpiperazine and N‐ethylpiperazine ring, respectively, have good DPPH scavenging abilities with IC50=0.18, 0.58 and 0.93 mM, as compared to ascorbic acid (IC50=0.05 mM), while the best DPPH scavenger is NO2‐substituted compound (IC50=0.08 mM). Also, compound with N‐(2‐hydroxyethyl)piperazine moiety emerged as the best NO radical scavenger with IC50=0.28 mM. Molecular docking studies showed that the present compounds are orthosteric inhibitors with their quinoline, pyrimidine, and 4‐amino units as crucial pharmacophores furnishing α‐glucosidase binding at the catalytic site. Taken together, these compounds exhibit dual potentials; i. e., potent α‐glucosidase inhibitors and excellent free radical scavengers. Hence, they may serve as structural templates in the search for agents to manage Type 2 diabetes mellitus. Finally, in preliminary assays investigating the anti‐tubercular potential of these compounds, two pyrazolopyrimidine series compounds and a 7‐chloro‐N‐phenylquinolin‐4‐amine hybrid showed sub‐10 μM whole‐cell activities against Mycobacterium tuberculosis.
摘要 合成了两个喹啉基杂交化合物库 1-(7-氯喹啉-4-基)-1H-吡唑并[3,4-d]嘧啶-4-胺和 7-氯-N-苯基喹啉-4-胺,并评估了它们的 α-葡萄糖苷酶抑制和抗氧化特性。与参考抑制剂阿卡波糖(IC50=51.73 μM)相比,分别带有 4-甲基哌啶和对三氟甲氧基的化合物显示出最有前途的 α-葡萄糖苷酶抑制活性,IC50=46.70 和 40.84 μM。结构-活性关系分析表明,环状仲胺垂体和对位苯基取代基是造成不同酶抑制作用的原因。抗氧化分析进一步表明,与抗坏血酸(IC50=0.05 mM)相比,分别具有 N-甲基哌嗪和 N-乙基哌嗪环的化合物具有良好的 DPPH 清除能力,IC50=0.18、0.58 和 0.93 mM,而最佳的 DPPH 清除剂是 NO2 取代的化合物(IC50=0.08 mM)。此外,含有 N-(2-羟乙基)哌嗪分子的化合物是最佳的 NO 自由基清除剂,IC50=0.28 mM。分子对接研究表明,这些化合物是正交型抑制剂,其喹啉、嘧啶和 4-氨基单元是在α-葡萄糖苷酶催化位点结合的关键药效团。综合来看,这些化合物具有双重潜力,即既是强效的 α-葡萄糖苷酶抑制剂,又是出色的自由基清除剂。因此,它们可以作为结构模板,用于寻找控制 2 型糖尿病的药物。最后,在研究这些化合物抗结核潜力的初步试验中,两个吡唑嘧啶系列化合物和一个 7-氯-N-苯基喹啉-4-胺杂合物对结核分枝杆菌显示出低于 10 μM 的全细胞活性。