A series of novel matrine derivatives incorporating thiosemicarbazide moieties was designed and synthesized. The in vitro cytotoxicity of these compounds was evaluated against four human cancer cell lines: MCF-7, HepG2, SGC-7901, and A549. Results demonstrated that their cytotoxic activity was significantly higher than that of matrine. Notably, compound 11d exhibited potent antiproliferative activity, exhibiting an IC50 value of 8.06 ± 0.1 μM against A549 cells. Further investigations revealed that compound 11d inhibits tumor cell proliferation by inducing S-phase cell cycle arrest. This inhibitory effect is associated with enhanced mitochondria-mediated apoptosis, manifested as suppressed cell migration and increased intracellular reactive oxygen species (ROS) levels. These effects were accompanied by increased p53 protein expression, upregulation of Bax expression, downregulation of Bcl-2 expression, and activation of the caspase cascade. Additionally, compound 11d functions as a topoisomerase I inhibitor, disrupting DNA synthesis and transcription, thereby impeding cancer cell proliferation. Using ADMET predictive analysis, the in vivo pharmacokinetic properties of the optimized derivatives were preliminarily evaluated, thus providing a critical theoretical foundation for subsequent in-depth preclinical investigations.
