Synthesis, spectroscopic characterization of new series of alizarin derivatives and their anti-microbial activities: DFT and molecular docking approach

Abstract

A series of novel alizarin-derived containing a pyridine moiety were designed and synthesized with a reaction yield of 89–93% as antibacterial agents. Characterization of the three ligands was deduced by the analysis of NMR (1H and 13C NMR), UV–Vis, FT-IR spectroscopy, and mass spectrometry technique. Standard functional B3LYP/6–31G(d,p) density functional theory (DFT) calculations method in the aqueous phase were utilized for these synthesized molecules. The optimized molecular geometry, thermal free energies, molecular electrostatic potential and nonlinear optical studies were performed. The charge transfer inside the molecule was demonstrated using HOMO-LUMO energy calculations and Mulliken atomic charges. Furthermore, docking studies were performed to predict and describe the interactions of FabH enzyme with the three alizarin derivatives. This result demonstrates that the title compounds have a potent inhibitor effect against bacterial infection.