An efficient synthetic route for the synthesis of 2H-pyrazolo[4,3-c]pyridines, primarily varying by the substituents at the 2-, 4- and 6-positions, is described here. A Sonogashira-type cross-coupling reaction was employed to yield 3-alkynyl-1H-pyrazole-4-carbaldehydes, ethanones and propanones from the corresponding 1H-pyrazol-3-yl trifluoromethanesulfonates. Subsequent treatment of the coupling products with dry ammonia afforded a versatile library of 2H-pyrazolo[4,3-c]pyridines, which were then evaluated for their cytotoxicity against K562 and MCF-7 cancer cell lines. The most potent of these compounds displayed low micromolar GI₅₀ values in both cell lines. Active compounds induced dose-dependent cell-cycle arrest in mitosis, as shown by flow cytometric analysis of DNA content and phosphorylation of histone H3 at serine-10. Moreover, biochemical assays revealed increased activities of caspases-3/7 in treated cells, specific fragmentation of PARP-1, and phosphorylation of Bcl-2, collectively confirming apoptosis as the mechanism of cell death.

本文描述了一种合成2 H-吡唑并[4,3- c ]吡啶的有效合成途径，主要由2、4-和6-位的取代基决定。利用Sonogashira型交叉偶联反应从相应的1 H-吡唑-3-基三氟甲烷磺酸酯产生3-炔基-1 H-吡唑-4-甲醛，乙酮和丙烷。随后用干燥的氨水处理偶联产物，得到了2 H-吡唑并[4,3- c ]吡啶的多功能文库，然后评估了其对K562和MCF-7癌细胞系的细胞毒性。这些化合物中最有效的化合物显示出低的微摩尔GI ₅₀两个单元格行中的值。活性化合物在有丝分裂中诱导了剂量依赖性的细胞周期停滞，如流式细胞仪分析的DNA含量和丝氨酸10处组蛋白H3的磷酸化所示。此外，生化分析显示，caspases-3 / 7在处理过的细胞中具有增强的活性，PARP-1的特异性片段化，以及Bcl-2的磷酸化，共同证实了凋亡是细胞死亡的机制。