PH dependency of the structural and photophysical properties of the atypical 2',3-dihydroxyflavone.

ABSTRACT: 2',3-Dihydroxyflavone (2'3HF) is a natural flavonol that has barely ever been studied, however the scarce studies of its physico-chemical properties have highlighted its atypical behaviour. We present a structural and spectral study of 2'3HF, performed using UV-visible absorption and fluorescence spectroscopies, coupled with DFT and TD-DFT calculations. Although its structure is close to that of 3-hydroxyflavone, 2'3HF shows a much lower pK _a value. We show that the origin of this particularity is the substitution by a hydroxyl group on position 2', that induces a stronger inter-ring interaction weakening the bonding of the proton at position 3. The main absorption band of the is red-shifted upon deprotonation. The remaining proton is highly bonded in between oxygen atoms

SUBMITTER: Labarriere L 

PROVIDER: S-EPMC9056863 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature