Synthesis, Molecular Docking Studies, and In vitro Anticancer Evaluation of Novel Tolfenamic Acid Derivatives

Background: Accumulating experimental evidence has demonstrated that tolfenamic acid (TA) has anticancer activity. TA has been shown to modulate the expression of several cancer-related genes involved in apoptosis and cell cycle arrest, as well as metastasis and angiogenesis. Objective: The current study was carried out to evaluate the anticancer activities of eight newly synthesized TA derivatives by conducting in silico molecular docking studies and in vitro biological evaluations to validate their VEGFR-2 tyrosine kinase inhibitory activities. Methods: The novel TA derivatives (3A-F-5) were obtained by reacting TA hydrazide with substituted aldehydes, phthalic anhydride, and succinic anhydride. Spectroscopic techniques were used to characterize the target molecules. Docking studies were performed to determine the binding patterns to the potential molecular target VEGFR-2, and these were compared with the results of the in vitro VEGFR-2 tyrosine kinase (TK) inhibition assay. Results: Our findings indicate that the newly synthesized compounds are cytotoxic, with compound 4 being the most potent. Additionally, all compounds inhibited VEGFR-2 TK activity. The EC50 value of compound 4 was nearly identical to that of the conventional VEGFR TK inhibitor sorafenib. SAR studies revealed that the presence of an aryl or a heteroaryl fragment attached to the hydrophilic linker (as found in compound 4) is crucial to the anticancer activity. Conclusion: The outcomes suggest that the isoindoline derivative (compound 4) is a good candidate for further investigation. The docking results provide evidence for a correlation between the experimental and predicted VEGFR-2 TK inhibitory activity. Moreover, ADMET studies indicate that all ligands have good pharmacokinetic properties.