Copper(II) thiosemicarbazonate molecular modifications modulate apoptotic and oxidative effects on U937 cell line

► Two copper thiosemicarbazonates cytotoxic effects are compared using U937 cells. ► The morpholine derivative is more effective in cell growth inhibition. ► The morpholine complex induces apoptosis. ► ROS and TBARS increased, GSH levels decrease and SOD is activated. ► The complexes differently interact with DNA and induce structure modifications.