Zn(II), Cu(II), and Fe(III) complexes of 2-(((4-(Methylselanyl)phenyl)imino)methyl)phenol: Synthesis, characterization, and multidisciplinary investigations

Organoselenium (OSe) Schiff bases and their corresponding complexes have recently shown promising biological activities. In this work, the synthesis of a novel selenated Schiff base, namely 2-(((4-(methylselanyl)phenyl)imino)methyl)phenol (MeSeOH), is described, starting from 4-(methylselanyl)aniline and 2-hydroxybenzaldehyde. Furthermore, their Zn(II), Cu(II), and Fe(III) chelates were also synthesized and characterized using various spectroscopic techniques, and were found to exist in octahedral geometry. Moreover, their antimicrobial, antitumor, and antioxidant activities were evaluated against multiple pathogens, tumors, and healthy cells, as well as using the SOD and DPPH assays. Computational analysis revealed that the ligand exhibits lower reactivity relative to its metal complexes, based on the ΔE gap and η values, which represent the energy gap and hardness, respectively. The parameters examined in this study offered valuable insight into the bonding, electronic properties, reactivity, and polarity of the OSe compounds under investigation. Ultimately, these findings demonstrated that the synthesized OSe Schiff base complexes exhibited promising biological activity, thereby highlighting their potential application in drug design and development. The examined MeSeOH analogue together with its Fe, Cu, and Zn complexes were docked against the SARS-CoV-2 M^pro target (PDB ID: 2Z94) to investigate their anti-SARS-CoV-2 potential further. Overall, the OSe agents exhibited promising antitumor, antimicrobial, and antioxidant properties, and the docking and computational studies proposed their potential as anti-SARS-CoV-2 agents. Accordingly, these results highlight their considerable potential in drug design and development, especially for therapeutic investigations against cancer, microbial infections, and viral diseases.