Synthesis, Characterization, Biological Activity and Molecular Docking Studies of Phthalic Acid based Macrocyclic Transition Metal Complexes

Abstract

A novel series of macrocyclic complexes of [M(L)Cl2] (M = Co(II), Ni(II) and Cu(II), L = macrocyclic ligand) were synthesized by template condensation method using 3,4-diaminotoluene and phthalic acid in the presence of divalent transition metal ions e.g., Co(II), Ni(II) and Cu(II) in their chloride form. These synthesized metal complexes were fully characterized by spectroscopic techniques, namely UV-Visible, IR, ESR and ESI-MS. Their thermal behaviour was determined by TGA and DTA. Further these macrocyclic complexes were screened for antimicrobial activity against bacterial species (Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa and Escherichia coli) and fungi (Aspergillus niger and Candida albicans) and then compared against standard drug streptomycin and itraconazole, respectively. In addition to these the antioxidant activity of the macrocyclic complexes were also investigated through scavenging effect on the DPPH radicals. Finally, the biological potency of synthesized compounds was evaluated using Auto Dock Vina. All the synthesized macrocyclic complexes were found to be potent against bacterial and fungal species, which suggest their potential application as antibacterial and antifungal agents.