β‐ and γ‐Amino Acids‐Containing Cu(II) Coordination Complexes: Synthesis, Structure, and Antibacterial Activity

Abstract Two coordination complexes of Cu(II) with N ‐phthaloyl‐β‐alanine and N ‐phthaloyl‐γ‐aminobutyric acid have been achieved in this work. The Cu(II) complexes have been characterized and studied by FT‐IR, absorption and emission spectroscopy, mass spectrometry, EPR, TGA, and FE‐SEM. The crystallographic structural descriptions along with the antibacterial activity of these two coordination complexes have been explored. From X‐ray crystallography, in complex 1 , the Cu(II)‐center shows a penta‐coordinated geometry with oxygen donor sites from two N ‐phthaloyl‐β‐alanine, two pyridines, along with one coordinated water molecule. In complex 2 , the Cu(II)‐center shows a hexa‐coordinated geometry with oxygen donor sites from two N‐phthaloyl‐γ‐aminobutyric acid and two pyridines. The complexes adopt a paddle‐wheel conformation that eventually forms a porous structure in higher‐order packing through multiple π‐π stacking interactions. We have also investigated their inhibitory effects against both gram‐negative ( Escherichia coli ) and gram‐positive ( Bacillus subtilis ) bacteria. The Cu(II) complex with N ‐phthaloyl‐β‐alanine showed the highest inhibitory effects. Gaining insight into the atomic level details can help design tailor‐made coordination complexes with enhanced antibacterial performance.