Synthesis and biological evaluation of 6H-pyrido[2′,1′:2,3]imidazo[4,5-c]isoquinolin-5(6H)-ones as antimitotic agents and inhibitors of tubulin polymerization.

Abstract: A series of 6H-pyrido[2′,1′:2,3]imidazo[4,5-c]isoquinolin-5(6H)-ones have been synthesized and evaluated for their antiproliferative activities. Among them, compounds 2j and 4d displayed potent cytotoxic activities in vitro against HeLa cell line with IC50 values of 0.07 and 0.06μM, respectively. In general, the antiproliferative activities are correlated with the inhibitory effect on tubulin polymerization and binding property of the colchicine binding site. In addition, flow cytometry and immunofluorescence analysis revealed selected compounds caused G2/M phase arrest of the cell cycle and disruption of the mitotic spindle assembly, which had correlation with proliferation inhibitory activity. [Copyright &y& Elsevier]