Design, synthesis, anticancer evaluation, and molecular dynamics-based computational investigation of novel pyrimidine-benzothiazole/phenyl hybrid-based VEGFR-2-targeted derivatives with antioxidant, DNA nicking, DNA interaction, and cytotoxicity studies.

A series of novel pyrimidine-based benzothiazole/phenyl hybrids was rationally designed and synthesized via molecular hybridization to develop promising anticancer agents. The compounds were evaluated against human lung carcinoma (A549) and breast adenocarcinoma (MCF-7) cell lines, while HEK-293 cells were used to assess selectivity toward normal cells. Among the derivatives, K12, K5, and K4 showed potent activity against A549 cells, with IC50 values of 6.18, 7.01, and 7.54 μM, respectively. K5 and K12 also showed significant activity against MCF-7 cells, with IC50 values of 8.33 and 9.30 μM, respectively. All compounds displayed minimal cytotoxicity toward HEK-293 cells, indicating favorable selectivity for cancer cells. UV-Vis DNA-binding studies suggested a probable intercalative binding mode, while DNA nicking assays demonstrated protection against oxidative DNA damage. K12 showed the strongest DNA-binding affinity and DNA-protective activity. Molecular docking against the VEGFR-2 kinase domain (PDB ID: 4ASD), followed by 501 ns MD simulations, revealed stable protein-ligand complexes, supported by RMSD, RMSF, DCCM, PCA, and free energy landscape analyses. MM/GBSA calculations indicated favorable binding free energies, dominated by van der Waals interactions. Overall, K12 emerged as the most promising lead compound, combining potent antiproliferative activity, high selectivity, efficient DNA-binding characteristics, and robust computational performance, highlighting its potential for further development as a novel anticancer agent.