Design, synthesis and pro-apoptotic antitumour properties of indole-based 3,5-disubstituted oxadiazoles.

A series of new indole-based 3,5-disubstituted 1,2,4-oxadiazoles has been designed and synthesised as potential pro-apoptotic antitumour agents, via the base-catalysed condensation reaction between substituted amidoximes and indole esters. Evaluation of antiproliferative activity against the human cancer cell lines COLO 320 (colorectal) and MIA PACA-2 (pancreatic) revealed IC(50) values in the low micromolar range. Selected compounds were able to trigger apoptosis in sensitive cell lines, for example via activation of caspase-3/7, demonstrating that indole-based oxadiazoles possess in vitro antitumour and pro-apoptotic activity.