Synthesis, Structural Elucidation, Cytotoxic, Antimicrobial, Antioxidant, Density Functional Theory and Molecular Docking Studies of Mononuclear Ru(II) Complexes of N 4 O 4 -Bearing Macrocyclic Ligands

The novel macrocyclic ligands (N 4 MacL 1 -N 4 MacL 3 ) and their Ru(II) complexes were synthesized by using 4-fulorobenzene-1,2-diamine, dicarboxylic acids (malonic acid, succinic acid, glutaric acid), and a 1:1 molar ratio of ligand to metal was used to create their metal complexes with the transition metals Ru (II). These metal complexes were identified using a variety of advanced methods, including, FTIR, 1 H-NMR, mass spectrophotometry, UV–Visible, PXRD, TGA and density functional theory (DFT) analysis. Kinetic and thermodynamic parameters were computed using the Coats-Redfern equations. Calculations based on molecular modelling (DFT) support the complexes' structural geometry. Synthesized macrocyclic compounds were tested for antimicrobial activity against bacterial strains B. subtilis, S. aureus, E. coli and K. pneumonia and fungal strains A. flavious and fusarium . When the ligands and their Ru(II) complexes were tested for their in vitro antimicrobial properties against some bacterial, fungal strains B. subtilis, S. aureus, E. coli , K. pneumonia and A. flavius, fusarium, respectively results revealed that the Ru(II) macrocyclic complexes were more effective against bacterial and fungal strains than tetraaza macrocyclic ligands (N 4 MacL 1 -N 4 MacL 3 ). The antioxidant capacity of ligands and Ru(II) complexes were also assessed using the DPPH free radical test, with an IC 50 range of 10.01–28.45 M. B. subtilis (PDB ID;5H67), S. aureus (PDB ID;3TY7), E. coli (PDB ID;3T88), K. pneumonia (PDB ID;6WII), and F. oxysporum (PDB ID;8EBB) proteins, were all subjected to docking studies using the AutoDock vina programme. Using the SRB test, the anticancer activity was assessed against four distinct cell lines HeLa, MCF-7, A549 and IMR-32. Comparing the ligands and complexes to the reference medication cis-platin revealed that it had far stronger cytotoxic effects. The research presented here proposes using these ligands in the creation of novel anticancer medications. Graphical Abstract