光笼型周期蛋白依赖性激酶2抑制剂的设计、合成及生物活性评价

Design, synthesis, and biological activity evaluation of photocaged cyclin-dependent kinase 2 inhibitors

摘要

基于周期蛋白依赖性激酶 2(CDK2) 抑制剂 AT7519 与靶点的精确结合模式，设计并合成一系列新型光笼化合物，以实现对分子活性的精准光控调控。以 AT7519 为母核结构，在其吡唑环 NH 和哌啶环 NH 两个关键药效团位点引入不同类型的光笼基团，设计并合成了 8 个双光笼化合物。利用核磁共振波谱和质谱确证所有目标化合物的结构，并系统考察了其光化学性质，包括光解离波长、光解动力学及光解效率。采用 MTT 比色法评估化合物对人 HCT116 结肠癌细胞增殖的光控抑制活性。研究结果表明，光笼基团的类型及其引入位点显著影响了光笼化合物的光响应特性。化合物1a、1b 和 2d 表现出优异的光解效率，光解转化率均在 90% 以上。其中，化合物 1b 和 2d 具有显著的光控活性差异：在黑暗条件下，其对细胞增殖的抑制作用极弱，半数抑制浓度 (IC₅₀) 均大于 150 μmol/L；而在光照后，其抑制活性显著增强，与阳性对照药 AT7519 水平相当。综上所述，化合物 1b 和 2d 展现出优异的光控开关性能，可作为潜在的光控 CDK2 抑制剂候选药物用于后续研究。

Abstract

This study aimed to design and synthesize a series of novel photocaged compounds based on the precise binding mode of cyclin-dependent kinase 2 (CDK2) inhibitor AT7519 with its target, to achieve precise optical control over molecular activity. Using AT7519 as the structural foundation, different types of photoremovable protecting groups were introduced at its key interaction sites (the NH of the pyrazole ring and the NH of the piperidine ring), resulting in the synthesis of eight dual-photocaged compounds. Their structures were confirmed by NMR and mass spectrometry, and their photochemical properties —including photolysis wavelength, photolysis time, and photolysis efficiency—were systematically evaluated. The optically controlled inhibitory effects of the compounds on HCT116 cell proliferation were assessed using MTT assay. The photoresponsive characteristics of the photocaged compounds were significantly influenced by the type of photoremovable protecting group and its introduction site. Among them, compounds 1a, 1b, and 2d exhibited excellent photolysis efficiency, each achieving a rate exceeding 90%. Particularly, compounds 1b and 2d demonstrated excellent optically controlled activity: under dark conditions, their half maximal inhibitory concentration (IC₅₀) values were both greater than 150 µmol/L, indicating negligible cell proliferation inhibitory activity; however, upon irradiation, their cell proliferation inhibitory activity significantly increased, with IC ₅₀ values comparable to those of the positive control AT7519. The obtained compounds 1b and 2d possess excellent optically controlled properties, and can be further investigated as potential candidates for optically controlled CDK2 inhibitors.

关键词

细胞周期蛋白依赖性激酶 / AT7519 / 光药理学 / 光保护基

Key words

cyclin-dependent kinase / AT7519 / photopharmacology / photoprotective group

参考文献

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基金资助

无锡转化医学中心项目(2022ZHZD02)