In this work, readily achievable synthetic pathways were utilized for construction of a library of /S analogues based on the pyrazolopyrimidine scaffold with terminal alkyl or aryl fragments. Subsequently, we evaluated the anticancer effects of these novel analogs against the proliferation of various cancer cell lines, including breast, colon, and liver lines. The results were striking, most of the tested molecules exhibited strong and selective cytotoxic activity against the MDA-MB-231 cancer cell line; IC 1.13 µM. Structure-activity relationship (SAR) analysis revealed that -substituted derivatives generally enhanced the cytotoxic effect, particularly with aliphatic side chains that facilitated favorable target interactions. We also investigated apoptosis, DNA fragmentation, invasion assay, and anti-migration effects, and discussed their underlying molecular mechanisms for the most active compound 7c. We demonstrated that 7c -propyl analogue could inhibit MDA-MB-231 TNBC cell proliferation by inducing apoptosis through the regulation of vital proteins, namely c-Src, p53, and Bax. In addition, our results also revealed the potential of these compounds against tumor metastasis by downregulating the invasion and migration modes. Moreover, the inhibitory effect of active analogs against c-Src kinase was studied and proved that might be the main cause of their antiproliferative effect. Overall, these compelling results point towards the therapeutic potential of these derivatives, particularly those with -substitution as promising candidates for the treatment of TNBC type of breast cancer.

中文翻译：

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N-和S-取代的吡唑并嘧啶：一类有前景的新型有效c-Src激酶抑制剂，具有显着的抗肿瘤活性

在这项工作中，利用易于实现的合成途径来构建基于具有末端烷基或芳基片段的吡唑并嘧啶支架的/S类似物文库。随后，我们评估了这些新型类似物对各种癌细胞系（包括乳腺癌、结肠癌和肝癌细胞系）增殖的抗癌作用。结果令人震惊，大多数测试分子​​对 MDA-MB-231 癌细胞系表现出强烈的选择性细胞毒活性； IC 1.13 µM。构效关系（SAR）分析表明，β-取代衍生物通常会增强细胞毒性作用，特别是具有促进有利靶点相互作用的脂肪族侧链。我们还研究了细胞凋亡、DNA 断裂、侵袭测定和抗迁移作用，并讨论了最活跃的化合物 7c 的潜在分子机制。我们证明，7c-丙基类似物可以通过调节重要蛋白（即 c-Src、p53 和 Bax）诱导细胞凋亡，从而抑制 MDA-MB-231 TNBC 细胞增殖。此外，我们的结果还揭示了这些化合物通过下调侵袭和迁移模式来对抗肿瘤转移的潜力。此外，还研究了活性类似物对c-Src激酶的抑制作用，并证明这可能是其抗增殖作用的主要原因。总体而言，这些令人信服的结果表明了这些衍生物的治疗潜力，特别是那些带有β-取代的衍生物，作为治疗 TNBC 型乳腺癌的有希望的候选者。