A new ternary Cu (II) complex with 4,7‐dimethyl‐1,10‐phenanthroline and NOO‐type tridentate Schiff base ligand: Synthesis, crystal structure, biomacromolecular interactions , and radical scavenging activities

NOO‐type tridentate Schiff base, N ‐salicylidene‐2‐aminobenzoic acid, (H 2 L), and its ternary Cu (II) complex containing H 2 L Schiff base and 4,7‐dimethyl‐1,10‐phenanthroline (4,7‐dmphen), [Cu(4,7‐dmphen)(H 2 L)] 2 7H 2 O, have been synthesized and characterized by CHN analysis, ESI‐MS, FTIR, and single‐crystal X‐ray diffraction techniques. The interaction of alone H 2 L Schiff base ligand and ternary Cu (II) complex with biomacramolecules {calf thymus DNA (CT‐DNA) and bovine serum albumin (BSA)} has been investigated by electronic absorption and fluorescence spectroscopy. The experimental results indicate that H 2 L Schiff base ligand and ternary Cu (II) complex bind to CT‐DNA by means of a moderate intercalation mode. Furthermore, the fluorescence quenching mechanism between H 2 L Schiff base ligand and ternary Cu (II) complex with BSA possesses a static quenching process. Radical scavenging activity of H 2 L Schiff base ligand and ternary Cu (II) complex was measured in terms of EC 50 , using the DPPH and H 2 O 2 methods. Biomacromolecule interactions and scavenging activity studies revealed that ternary Cu (II) complex yielded better results than H 2 L Schiff base ligand alone.