Synthesis and Evaluation of 3,5‐Disubstituted‐1,2,4‐Oxadiazolyl Benzamides as Potential Anti‐Breast Cancer Agents: In Vitro and In Silico Studies

Herein, the synthesis, anti-cancer evaluation, and in silico studies of a series of 1,2,4-oxadiazole compounds (8-15) are disclosed. The synthesized molecules were tested in vitro for anti-cancer activity against MCF-7, MDA-MB-231, HeLa, Ishikawa cell lines and human embryonic kidney (HEK-293) cell lines. Among the synthesized compounds, 9 and 15 exhibited significant cytotoxicity, with IC₅₀ values of 7.82 μM and 6.02 μM, respectively, against MCF-7 cell line, better than that of anti-breast cancer drug, tamoxifen (IC₅₀=11.92 μM), used as control. Significantly, both 9 and 15 exhibited very low toxicity (IC₅₀>20 μM) against normal HEK-293 cells. This suggests them as potentially effective anti-cancer lead molecules. The in vitro anti-cancer data was supported by in silico studies which also identified compounds 9 and 15 as potent inhibitors of the 17β-hydroxysteroid dehydrogenase1 (17β-HSD1) proteins, demonstrating strong interactions and stability The atom-based QSAR model exhibited high accuracy, significant regression, and predictive reliability, aiding in understanding and optimizing biological activity. The drug-likeness study of compounds 9 and 15 indicated favorable pharmacokinetics, with in silico toxicity predictions showing compound 15 to be non-toxic. These findings suggest compounds 9 and 15 as potential lead molecules against breast cancer.