New thiazole-2(3H)-thiones containing 4-(3,4,5-trimethoxyphenyl) moiety as anticancer agents

A new series of thiazole-2(3H)-thiones containing 4-(3,4,5-trimethoxyphenyl) moiety were synthesized as diaryl-heterocylic analogs of combretastatin A-4 with anticancer activity. The cytotoxicity evaluation of synthesized compounds against cancer cell lines (A549, MCF-7 and SKOV3) revealed that most of them had potent cytotoxic activity toward all tested cell lines (IC₅₀s < 10 μg/mL). Among them, 3-(chlorobenzyl) derivatives 5c and 5d showed the best inhibitory effect on MCF-7 cells (IC₅₀ values of 1.14 and 2.41 μg/mL, respectively). Furthermore, the ability of tubulin polymerization inhibition and apoptosis induction were evaluated for the promising compounds 5c and 5d. Results suggested that these compounds remarkably inhibit tubulin polymerization and induce apoptosis resulting in cell death. In vitro studies revealed that these compounds had no significant cytotoxicity against normal cells at the concentrations required for growth inhibition of cancer cells. In vitro biding assay and in silico docking study also confirmed the binding of prototype compound to the colchicine binding site of tubulin.