Synthesis, structural characterization, and biological evaluation of novel iodophenyl-anthracene Schiff bases: Insights from X-ray crystallography, DFT, antibacterial, and molecular docking studies

Abstract

Two novel iodophenyl-anthracene Schiff bases, (E)-1-(10-bromoanthracen-9-yl)-N-(2-iodophenyl)methanimine (I5) and (E)-1-(10-bromoanthracen-9-yl)-N-(4-iodophenyl)methanimine (I6), were synthesized and extensively characterized using advanced spectroscopic techniques (FT-IR, NMR, UV–Vis), single-crystal X-ray diffraction, Hirshfeld surface analysis, Density Functional Theory (DFT) calculations, and molecular docking studies. Structural analyses confirmed the presence of the characteristic azomethine linkage (–CH=N–) and elucidated distinct supramolecular architectures stabilized predominantly by π–π stacking, halogen bonding, and non-covalent interactions. Hirshfeld surface mappings quantified intermolecular interactions, revealing significant contributions from aromatic stacking and halogen-involved contacts. Quantum chemical analyses highlighted extensive electron delocalization across both compounds, with subtle differences in electronic descriptors suggesting slightly higher reactivity for I6. Molecular docking simulations against key proteins from Klebsiella pneumoniae, Staphylococcus aureus, and Candida albicans demonstrated potent binding affinities, indicating robust antimicrobial potential. Experimental antimicrobial assays supported these computational findings, with both compounds exhibiting selective inhibition profiles against bacterial and fungal pathogens. Collectively, these multidisciplinary insights establish iodophenyl-anthracene Schiff bases as promising scaffolds for future antimicrobial agent development.