Synthesis, crystal structure and anticancer activity of a novel ternary copper(II) complex with Schiff base derived from 2-amino-4-fluorobenzoic acid and salicylaldehyde

Abstract

The ternary copper(II) complex with 1,10-phenanthroline and Schiff base derived from 2-amino-4-fluorobenzoic acid and salicylaldehyde, was synthesized and characterized by IR and 1H NMR spectroscopy, elemental analysis, and single crystal X-ray diffraction. X-ray crystallography shows that the copper atom adopts square pyramidal geometry and is five coordinated by the nitrogen atom from CN, two nitrogen atoms from 1,10-phenanthroline, the hydroxyl oxygen atom and the carboxylate oxygen atom. Our studies on the anticancer activity of the complex indicate that the complex can inhibit the cellular proliferation in human breast cancer MDA-MB-231 cells. In addition, it has proteasome-inhibitory activity in human breast cancer MDA-MB-231 cells. The inhibition of the tumor proteasomal activity results in the accumulation of ubiquitinated proteins and ubiquitinated form of IκB-α, a natural proteasome substrate, followed by induction of apoptosis. The results suggest that the title complex, as a potent proteasome inhibitor, has potential to be developed into a novel anticancer drug.