Influence of Hydroxyl Functional Group on the Structure and Stability of Xanthone: A Computational Approach

Abstract

The present work addresses computational research focused on the energetic and structural properties of four isomers monohydroxyxanthone, using the G3(MP2)//B3LYP method, in order to evaluate the influence of the hydroxyl (—OH moiety) functional group on the xanthone molecule. The combination of these computational results with previous experimental data of these compounds enabled the determination of their enthalpies, entropies and Gibbs energies of formation, in the gaseous phase, and consequently to infer about the relative thermodynamic stability of the four isomers. Other issues were also addressed for the hydroxyxanthone isomers, namely the conformational and the tautomeric equilibrium analysis of the optimized molecular structures, the frontier orbitals, and the electrostatic potential energy maps. Complementarily, an energetic study of the intramolecular normalO—normalH⋯normalO hydrogen bond for 1-hydroxanthone was also performed.

From Natural Products to New Synthetic Small Molecules: A Journey through the World of Xanthones

“…As simple phenolic compounds, naturally-occurring simple oxygenated xanthones have been described for their antioxidant properties that have been implicated in their hepatoprotective, anti-inflammatory, and cancer chemopreventive actions [ 18 ]. The influence of these substituents in the xanthone stability is important to understand the biological effects of these compounds [ 41 ]. Our group has been gathering physical-chemical-biological properties of these simple derivatives to use this information in drug design of more complex xanthones.…”

Spectral deep learning for prediction and prospective validation of functional groups

“…The arrangement of atoms within a molecule dictates its physical, chemical, and spectral properties. Small discrete, or large repeating arrangements of atoms which give rise to measurable changes in a molecule's reactivity, [1][2][3] boiling point, 4,5 melting point, 6,7 and other characteristics are called functional groups. Given the structural formula of a molecule, a chemist can identify functional groups present (e.g.…”

Synthesis of 1-Hydroxy-3-O-Substituted Xanthone Derivatives and their Structure-activity Relationship on Acetylcholinesterase Inhibitory Effect

“…For the alkylatedphenyl series (2o-2r), the presence of an aromatic ring in the side chain were con rmed by the observation of three additional methine proton peaks at the region of δ 7.1-7.3 ppm, in comparison to that of 1. On the other hand, the substitution of 1-OH was omitted due to a robust intramolecular hydrogen bonding with the adjacent carbonyl group 44 . The evidence is the presence of a down eld singlet at around δ 12.8 ppm, which is associated with the chelated hydroxyl group at position C-1 in the 1 H NMR spectra of 1 and 2a-2r.…”

“…This nding shows that the hydroxyl group at position C-1 of xanthone failed to contribute favourable effects to anti-AChE activities. This might be due to its close distance to the adjacent carbonyl group, resulting in a signi cant chelating effect 37,44 .…”