Scrutinizing the DNA interactions and antimicrobial potential of mixed ligand metal complexes incorporating salicylaldehyde-isoniazid Schiff base ligand and quercetin

Abstract

In this work, four mixed ligand transition metal complexes were synthesized to achieve the maximum level of biological efficiency. These complexes were designed by employing a Schiff base incorporating salicylaldehyde and isoniazid (primary ligand), along with quercetin as the co-ligand. Notably, the quercetin meaning a phenolic compound with a greater number of hydroxyl groups, is being used to assess its impact on biological activity. Elemental analysis and various spectroscopic techniques confirm the formation of the complexes. Physico-chemical analyses indicate that all the synthesized metal(II) complexes exhibit an octahedral geometry. The antimicrobial properties of both the ligand and metal(II) complexes were assessed against different bacterial and fungal strains. Additionally, the SWISS ADME online tool was employed to assess their drug-like properties and pharmacokinetic profiles. Further investigations into the DNA binding activity of these metal complexes were conducted using UV absorption studies and viscosity titrations, which supported an intercalative binding mechanism. Notably, molecular docking studies were performed to evaluate interactions with the 1BNA. The outcome of this work suggests that the synthesized complexes exhibit higher biological efficiency when related to the isoniazid incorporated Schiff base ligand due to chelation effect.