Electronic transitions of neutral and anionic quinolinone HIV-1 integrase inhibitor: Joint theory/experiment investigation

Abstract In this joint experimental and theoretical study, the solution-state conformation of [6-bromo-1-(4-fluorophenylmethyl)-4(1 H )-quinolinon-3-yl)]-4-hydroxy-2-oxo-3-butenoic acid (QDKA), a potential HIV-1 integrase inhibitor, is investigated by using UV–visible spectroscopy and Time-Dependent Density Functional Theory. The neutral, mono-anionic and di-anionic species have been identified and their spectral characteristics rationalized. The possibility of forming enol tautomers and keto structures is assessed.