NOO-type tridentate Schiff base ligand and its one-dimensional Cu(II) coordination polymer: Synthesis, crystal structure, biomacromolecular interactions and radical scavenging activities

N-salicylidene-2-amino5-chlorobenzoic acid, (H2L), NOO-type tridentate Schiff base and its one-dimensional Cu (II) coordination polymer, [Cu-2(H2L)(2)(MeOH)(n), have been synthesized and characterized by CHN analysis, FTIR, (HNMR)-H-1, C-13 NMR, ESI-MS and XRD techniques. Interaction of the H2L Schiff base ligand and its the Cu(II) coordination polymer with biomacramolecules {calf thymus DNA (CT-DNA) and bovine serum albumin (BSA)} has been investigated by electronic absorption and fluorescence spectroscopy. The experimental outcomes indicate that the H2L Schiff base ligand and its the Cu(II) coordination polymer bind to CT-DNA by means of a moderate intercalation mode. Furthermore, the fluorescence quenching mechanism between the H2L Schiff base ligand and its the Cu(II) coordination polymer and BSA is a static quenching process. Radical scavenging activity of the H2L Schiff base ligand and its the Cu(II) coordination polymer was determined in terms of IC50, using the DPPH and H2O2 method. In biomacromolecules interaction and radical activity studies, the Cu(II) coordination polymer was found to give better results than free the H2L Schiff base ligand.

Automated summary

In this study, N-salicylidene-2-amino-5-chlorobenzoic acid (H2L) and its Cu(II) coordination polymer were synthesized and characterized, with their interactions with biomacromolecules investigated. The results indicated that the mode of binding with DNA and protein differed between the two compounds, with the Cu(II) coordination polymer showing superior activity in biomacromolecules interaction and radical scavenging compared to the free H2L Schiff base ligand.