Design, synthesis and anticancer activity of 5-aryl-4-(4-arylpiperazine-1-carbonyl)-1,2,3-thiadiazoles as microtubule-destabilizing agents.

Hereby, we report our efforts on discovery and optimization of a new series of 5-aryl-4-(4-arylpiperazine-1-carbonyl)-1,2,3-thiadiazoles as new microtubule-destabilizing agents along our previous study. Guided by docking model analysis, we introduced the 1,2,3-thiadiazole moiety containing the hydrogen-bond acceptors as B-ring of XRP44X analogues. Extensive structure modifications were performed to investigate the detailed structure and activity relationships (SARs). Some compounds exhibited potent antiproliferative activities against three human cancer cell lines (SGC-7901, A549 and HeLa). The compound 5m exhibited the highest potency against the three cancer cell lines. The tubulin polymerization experiments indicated that compound 5m effectively inhibited the tubulin polymerization, and immunostaining assay revealed that it significantly disrupted microtubule dynamics. Moreover, cell cycle studies revealed that compound 5m dramatically arrested cell cycle progression at G2/M phase.