Oxindoline Containing Thiazolidine‐4‐one Tethered Triazoles Act as Antimitotic Agents by Targeting Microtubule Dynamics

Abstract

Oxindoline containing thiazolidine‐4‐ones linked triazole hybrids (24 a–l) series were synthesized by multistep synthesis and tested for their cytotoxic activity against four human cancer cell lines. Significantly higher susceptibility was observed in liver (HepG2) cancer cells. Among them conjugates 24 c and 24 e exhibited promising cytotoxicity with IC50 values of 1.64 μM, and 2.07 μM respectively when compared to the standard 5‐fluorouracil (IC50=20.8 μM) against the HepG2 cell line. Later on, these compounds changed the morphology of HepG2 cells and significantly inhibited colony formation in HepG2 in a dose‐dependent manner. The scratch assay divulged that these compounds decreased wound size and inhibited cell migration. Interestingly, they induced the cell cycle arrest at the S phase. Moreover, the DCFDA assay indicated ROS production proportionate to compound dose and AO/Eb staining revealed increased apoptotic cell count with higher doses. The tubulin polymerization assay reveals that they inhibited the microtubules and acted as antimitotic agents. In‐silico results of these conjugates also support their tubulin inhibitory properties. Interestingly, these compounds have adequate ADME‐toxicity parameters. Based on free energy calculation results, it was observed that these inhibitors influence the conformational flexibility of the target tubulin protein.