The pivotal role of the carbonyl group in methoxy chalcones: comprehensive analyses of the structure and computational insights into binding affinity towards monoamine oxidase enzymes†

Abstract

The present study explores the comprehensive investigations of two methoxy-oriented chalcone structures (HK1 and HK2), each featuring distinct halogen substituents (chlorine and bromine). The crystals of the derivatives were grown and confirmed via single-crystal X-ray diffraction (XRD), revealing that HK1 crystallizes in the orthorhombic system with the space group Pbca, while HK2 crystallizes in the monoclinic system with the space group P2₁/c. Intermolecular interactions, such as hydrogen bonding, π–π stacking, and van der Waals forces, were examined for their role in molecular assembly. Hirshfeld surface analysis and enrichment ratio provided further insights into these intermolecular interactions within the lattice. Density functional theory (DFT) calculations using the B3LYP functional and 6-311++G (d,p) basis set was employed to explore the electronic structure and physicochemical properties. Quantum theory of atoms in molecules (QTAIM) and non-covalent interaction (NCI) analyses elucidated the topology of these compounds. In silico biological studies of the derivatives were also carried out, focusing on their inhibitory potential targeting monoamine oxidase (MAO-A and MAO-B) enzymes. Drug-likeness was evaluated through ADME-T profiling predictions, followed by molecular docking and dynamics simulations to determine the favorable binding configurations within the MAOs. Dynamics simulations over a 100 ns period confirmed the stability of the ligand–protein complexes. Overall, the present study offers a deeper understanding of the structural intricacies of the reported molecules by providing valuable insights into their chemical and biological properties through molecular interactions.