Multifunctional Novel Lanthanide Complexes Based on Chromone Moiety for Corrosion Inhibition, Molecular Docking, and Anticancer and Antimicrobial Applications

Abstract

Two novel multifunctional complexes [M(CCAM)₂(NO₃)](NO₃)₂·C₂H₅OH (M = Dy (III)/Er (III); CCAM = 2-cyano-N′-((4-oxo-4H-chromen-3-yl)methylene)acetohydrazide) were synthesized and characterized via elemental and thermal analyses, molar conductivity, UV–vis., and FT-IR spectroscopy, revealing a 1:2 metal-to-ligand stoichiometry. The CCAM ligand coordinated with Dy(III) or Er(III) ions through nitrogen of azomethine and oxygen of the carbonyl and γ-pyran groups. Corrosion inhibition studies for Dy(CCAM), Er(CCAM), and CCAM on carbon steel (C-steel) in 1-M HCl showed Dy(CCAM) and Er(CCAM) as highly efficient, with Er(CCAM) offering the best protection. In a 1-M HCl solution, Fe²⁺ at the C-steel surface interacts with the CCAM, Dy(CCAM), and Er(CCAM) compounds, as demonstrated by UV–vis spectroscopy. At a concentration of 10⁻³ M, the Dy(CCAM) and Er(CCAM) compounds showed greater performance efficiency in the weight loss test in 1-M HCl solution, reaching 93.34% and 95.67%, respectively. The Langmuir adsorption isotherm pronounced the mixed adsorption mechanisms. The surface characteristics SEM, EDX, AFM, and contact angle measurements confirmed surface shielding. In vitro antibacterial and antifungal activity of the prepared compounds against organisms, including Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis as bacteria, and Candida albicans and Aspergillus fumigatus as fungi is carried out. Er(CCAM) inhibitor exhibits the greatest action against different tested antimicrobials. Additionally, the in vitro cytotoxicity of the produced complexes as growth inhibitory effects against Erlish Acities Carcinoma was ascertained. Er(CCAM) and Dy(CCAM) were found to have cytotoxic levels with (IC₅₀ of 64 and 65 μM), respectively. As a result, Er(CCAM) inhibitor is a more effective therapeutic approach for the creation of novel antimicrobial and antitumor agents. For Er(CCAM) superior corrosion protection, the theoretical studies of molecular docking and DFT and MD simulations validated the experimental results.