Study on Synthesis, Antiproliferative Properties, Immunomodulatory Effects, and Anti-Breast Cancer Activity of New Δ2-Pyrazoline-1H-1,2,3-Triazole Derivatives.

In the current work, a new series of novel Δ2-pyrazoline-1H-1,2,3-triazole derivatives (6a-6j and 7a-7f) were synthesized, followed by in situ biological evaluation to assess their antiproliferative and immunomodulatory potential against breast cancer cells (MDA-MB-231 and MCF-7), HUVECs, and PBMCs. The compounds demonstrated antiproliferative effects with IC50 values ranging from 116.92 to 549.73 µM. Seven compounds (6c, 6f, 6h, 6i, 7b, 7e, and 7f) exhibited promising antiproliferative activities with IC50 values below 140 µM in both MDA-MB-231 and MCF-7 cancer cell lines. Compound 7f demonstrated the highest antiproliferative effect with IC50 values of 116.92 µM in MDA-MB-231 and 124.72 µM in MCF-7, with an acceptable cytotoxicity profile in normal HUVEC cells (IC50 = 208.41 µM); thus, immunomodulatory effects of 7f on checkpoint signaling were further evaluated. Compound 7f showed a dose-dependent increase of TIGIT, PD-1, and LAG-3 expression in CD3+ T cells. These changes may enhance responsiveness to checkpoint-targeted therapies while reflecting complex regulation of T-cell function. In silico target fishing and molecular docking reflect calpain as a probable target for 7f, while DFT analysis indicates electrophilic and nucleophilic positions within 7f may help its interaction with the target. Molecular dynamics (MD) simulation supports strong binding of 7f with binding energy (-22.259 ± 4.71 kcal mol-1).