Synthesis of 3-N-/O-/S-methyl-imidazo[1,2-a] pyridine derivatives for caspase-3 mediated apoptosis induced anticancer activity

•49 compounds of imidazo[1,2-a]pyridines with different aminomethyl thiomethyl and oxomethyl moieties were synthesized.•5b showed anti-proliferative activity at 3.5 μM in HCT-116 cells in time dependent manner and no toxicity in normal cells.•ROS generation, decreased MMP and induced morphological changes in HCT-116 by 5b validate the apoptosis mechanism.•Anticancer potential of compound 5b was correlated with up regulation of PTEN and subsequent caspase-3 cleavage.•5b displayed strong binding at the active site of PI3Kα with the dock score of −6.932.