P2X7受体（P2X7R）在不同的病理条件中起着关键作用，尤其在癌症中过度表达和激活。我们探讨了三个新型吡嗪，喹啉-羧酰胺和噁二唑系列的结构活性关系（SAR）。它们在使用h-P2X7R-MCF-7细胞的Ca2 +移动试验中的选择性抑制效能在喹啉-羧酰胺和噁二唑衍生物中，通过苯环取代（-OCF3，-CF3和-CH3）分别得到改善。然而，高电负性的氟，氯和碘的取代增加了亲和力。 1e，2f，2e，1d，2g和3e对h-P2X7R（IC50值分别为0.457，0.566，0.624，0.682，0.813和0.890 µM）具有最强的选择性，在MCF-7和1321N1星形胶质细胞中对h-P2X4R、h-P2X2R、r-P2Y6R、h-P2Y2R、t-P2Y1R均无活性。细胞存活率（MTT测定，浓度为100 µM，细胞系）对于3e分别为62％（HEK-293T），70％（1321N1星形胶质瘤）和85％（MCF-7）。对于在所有未转染的细胞系中，2g和2e的细胞存活率均 >75％，1d的细胞存活率均>80％。选择性拮抗剂（10 µM）与对照（Bz-ATP）相比，抑制蛋白（anti-proliferative effects）为3e（11％），1d（19％），1e（70％，P=0.005）和2f（24％），表明P2X7R有参与。流式细胞仪显示，1e是最有前景的，细胞死亡率（PI阳性细胞）为35％，其次是2e（25％），2f（20％）和1d（19％），与对照组相比。通过荧光显微镜观察P2X7R转染细胞系的凋亡变化已确立。1e和2f在1X和2X IC50时导致细胞萎缩、核浓缩和PI / DAPI荧光增加。反应体模型预测了配体受体相互作用，并且所有化合物符合Lipinski规则。这些结果表明，吡嗪，喹啉-羧酰胺和噁二唑衍生物可能是中等强度的P2X7R拮抗剂，用于体内研究和抗癌药物开发。 版权所有© 2023 Elsevier Inc. 保留所有权利。

P2X7 receptor (P2X7R) has a key role in different pathological conditions, importantly overexpressed and activated in cancers. We explored the structure activity relationship (SAR) of three novel pyrazines, quinoline-carboxamide and oxadiazole series. Their selective inhibitory potency in Ca2+ mobilization assay using h-P2X7R-MCF-7 cells improved with phenyl ring substitutions (-OCF3, -CF3, and -CH3) in carboxamide and oxadiazole derivatives, respectively. However, highly electronegative fluoro, chloro, and iodo substitutions enhanced affinity. 1e, 2f, 2e, 1d, 2 g and 3e were most potent and selective toward h-P2X7R (IC50 values 0.457, 0.566, 0.624, 0.682, 0.813 and 0.890 µM, respectively) and were inactive at h-P2X4R, h-P2X2R, r-P2Y6R, h-P2Y2R, t-P2Y1R expressed in MCF-7 and 1321N1 astrocytoma cells. Cell viability (MTT assay at 100 µM, cell line) for 3e was 62% (HEK-293T), 70% (1321N1 astrocytoma) and 85% (MCF-7). >75% cell viability was noted for 2 g and >80% for 2e and 1d in all non-transfected cell lines. Anti-proliferative effects, compared to control (Bz-ATP), of selective antagonists (10 µM) were 3e (11%) 1d, (19%) 1e, (70%, P = 0.005) and 2f, (24%), indicating involvement of P2X7R. Apoptotic cell death by flow cytometry showed 1e to be most promising, with 35% cell death (PI positive cells), followed by 2e (25%), 2f (20%), and 1d (19%), compared to control. Fluorescence microscopic analysis of apoptotic changes in P2X7R-transfected cell lines was established. 1e and 2f at 1X and 2X IC50 increased cellular shrinkage, nuclear condensation and PI/DAPI fluorescence. In-silico antagonist modeling predicted ligand receptor interactions, and all compounds obeyed Lipinski rules. These results suggest that pyrazine, quinoline-carboxamide and oxadiazole derivatives could be moderately potent P2X7R antagonists for in vivo studies and anti-cancer drug development.Copyright © 2023 Elsevier Inc. All rights reserved.