Spectroscopic characterization of hydroxyquinoline derivatives with bromine and iodine atoms and theoretical investigation by DFT calculations, MD simulations and molecular docking studies

Abstract

© 2018 Elsevier B.V. In the present work, spectroscopic characterization of 5,7-dibromo-8-hydroxy quinoline (DBHQ(1)) and 5,7-diiodo-8-hydroxy quinoline (DIHQ(2)) has been obtained theoretically and experimentally. On the basis of potential energy distribution of vibrational modes, complete assignments of wavenumbers were performed yielding good agreement between experimental and theoretical wavenumbers. The HOMO-LUMO plots in the title molecules show the charge transfer in the molecular system through the conjugated paths. The electrophilic and nucleophilic sites are revealed from the molecular electrostatic potential maps. Experimental investigation encompassed spectroscopic characterization by FT-IR and Raman techniques while computational studies included DFT calculation, molecular dynamics (MD) simulations and molecular docking studies. MD simulations provided insights into the reactivity with water and with selected proteins. The molecular docking studies reveal that the ligands bind at the active site of the macromolecule and could restrict or block the functioning of Plasmodium falciparum dihydrofolatereductase-thymidylate synthase (PfDHFR-TS), there by acting as antiprotozoal agents. Drug activity and binding affinity of halogen positional changes in the title molecules with target protein were reported and this study thesaurus the effects of bio-efficiency in the molecule.