Biophysical and theoretical investigation of benzo[c]coumarin functionalized Schiff base with human serum albumin

The studies on molecular interactions of drug candidates with HSA have considerably contributed to the understanding of primary biological evaluation of potential drug. In this context, Schiff base, (E)-2-((2-hydroxy-3-methoxybenzylidene)amino)-6H-benzo[c]chromen-6-one (1) derived from o-vanillin and 6-amino-3,4-benzocoumarin was synthesized and characterized by elemental analysis, UV–Vis, IR, NMR, and ESI–MS. The HSA interaction studies of compound 1 was carried out employing various biophysical techniques, viz., UV–Vis titration, fluorescence quenching experiments, and CD measurements. The compound 1 displayed non-covalent hydrophobic mode of binding (Kb = 3.4 × 103 M−1). The fluorescence spectroscopic results revealed that compound 1 exhibited strong capability to quench the intrinsic fluorescence of HSA at Trp214 site (Ksv = 4.1 × 103 M−1). Also ADME and Lipinski’s drug-likeness predicted favorable physicochemical properties for oral bioavailability. To ascertain the specific binding to HSA, molecular docking was performed deciphering that electrostatic steady-state interactions have key role in binding of compound 1 to HSA with ΔG of −9.21 kcal mol−1. Moreover, DFT calculations were conducted to obtain electronic and structural properties of compound 1. The theoretical calculations and the experimental data are in well agreement, and hence, the findings suggest that compound 1 might exhibit a potent role in the biomedical and pharmaceutical application.