Synthesis of aryl dihydrothiazol acyl shikonin ester derivatives as anticancer agents through microtubule stabilization

The high incidence of cancer and the side effects of traditional anticancer drugs motivate the search for new and more effective anticancer drugs. In this study, we synthesized 17 kinds of aryl dihydrothiazol acyl shikonin ester derivatives and evaluated their anticancer activity through MTT assay. Among them, C13 showed better antiproliferation activity with IC50=3.14 ± 0.21 μM against HeLa cells than shikonin (IC50=5.75 ± 0.47 μM). We then performed PI staining assay, cell cycle distribution, and cell apoptosis analysis for C13 and found that it can cause cell arrest in G2/M phase, which leads to cell apoptosis. This derivative can also reduce the adhesive ability of HeLa cells. Docking simulation and confocal microscopy assay results further indicated that C13 could bind well to the tubulin at paclitaxel binding site, leading to tubulin polymerization and mitotic disruption.