Quantum chemical studies, spectroscopic NMR and FT-IR analysis, and molecular docking investigation of 3,3′-di-O-methyl ellagic acid (DMA) as a potent Mycobacterium tuberculosis agent

Tuberculosis which is mainly caused by Mycobacterium tuberculosis remains of public health importance due to the resistance of the causative pathogen to the present antibiotics used as treatment options. This resistance has led to the need for the discovery of new treatment options. Herein, the isolation, geometrical optimization, spectroscopic NMR and FT-IR analysis, a study of weak interactions, electronic properties, and the in-silico biological activity of 3,3′-di-O-methyl ellagic acid (DMA) were determined. In addition, the effect of solvent on the kinetic stability, reactivity, and other electronic properties of DMA was determined in three solvents; DMSO, methanol, and water. Also, the biological activity potential and the drug-likeness of DMA were determined using molecular docking protocol and ADMET studies. The studied compound was isolated using column and thin-layer chromatography techniques while characterization was done using spectroscopic techniques. Key vibrations in the compound are C = O vibrations, C = C vibrations, C-H vibrations, –CH3 vibrations, and O-H vibrations. A study of quantum descriptors revealed that DMA is more reactive in water with an energy gap of −3.162 eV and those in three solvents are −3.163, −3.944, and −4.3022 eV in methane, gas, and water respectively. The compound shows great optical potentials with dipole moments of 3.2415D, 5.221D, 5.2015D, and 4.469D in water, DMSO, methanol, and Gas-phase respectively which are greater than that of urea used in the comparison. The QTAIM analysis based on the bond ellipticity