Synthesis and design of manganese and nickel complexes with potential anticancer and antibacterial activities and antiviral properties for therapeutic applications

Abstract

Two new triclinic coordination complexes, [M(L)₂]·solvent {M = Mn(III) (1) and Ni(II) (2), L = synthesized tridentate Schiff base (SB) ligand, and solvent = DMF for complex (1) and DMSO for complex (2)}, were synthesized via a solvent-controlled reaction of Mn(OAc)₃·2H₂O/Ni(OAc)₂·4H₂O with SB. The solid-state structures of complexes (1) and (2) were determined using single crystal X-ray crystallography, which revealed a distorted octahedral geometry. Quantum computational calculations provided the structure–activity relationship. Hirshfeld surfaces were used to visualize and analyze intermolecular interactions. The CT-DNA and BSA protein binding interaction ability of complexes (1) and (2) were explored using a UV-visible study. To gain insights into the potential biological applications, a superior biological activity study (in vitro cytotoxicity) was conducted for investigating the effects of complexes (1) and (2) on breast cancer (MCF-7), cervical cancer (HeLa) and lung cancer (A549) cell lines, which were compared with those on the human normal kidney epithelial (NKE) cell line. Moreover, complexes (1) and (2) were tested for in vitro antibacterial activity. Besides biological potentials, we examined the antiviral molecular docking of complexes (1) and (2) with SARS-CoV-2 proteins (PDB ID: 8FXC, 6M0J and 8DV1), SARS-CoV-2 Omicron viral RBD proteins (PDB ID: 7TN0 and 7WBP) and a DNA-binding protein (PDB ID: 7UR0). The complexes showed good inhibition performance with the intended drug targets of the viral proteins and may be used as potential inhibitors for the development of new anti-SARS-CoV-2 Omicron drugs. Both the triclinic Mn(III) and Ni(II) complexes showed superior biological characteristics and antiviral properties for therapeutic applications.