In this work, we present a computational study on the antioxidant potential of myricetin 3-O-α-L-rhamnopyranoside (Compound M3) and myricetin 4-O-α-L-rhamnopyranoside (Compound M4). Structural parameters, bond dissociation enthalpies (BDEs), ionization potentials (IPs), proton dissociation enthalpies (PDEs), proton affinities (PAs), and electron transfer enthalpies (ETEs), which are properties connected with different mechanisms related to antioxidant activity, were determined using density functional theory (DFT) with B3LYP, LC-ωPBE, M06-2X, and BMK functionals along with the 6-311G(d,p) and 6-311+G(d,p) basis sets in the gas phase, water, and pentylethanoate. The values obtained were compared with results previously available in the literature for myricetin (the parent molecule and a well-known antioxidant) and myricetin 3,4-di-O-α-L-rhamnopyranoside (Compound M3,4).
View Article and Find Full Text PDFIn this work, we present a computational investigation on the reactions between two well-known antioxidants (quercetin and morin) and 2,2-diphenyl-1-picrylhydrazyl (DPPH). A density functional theory (DFT) approach with the B3LYP functional and the 6-31G(d,p) basis set was used for the simulations. The structural and energetic parameters (Gibbs free-energy, ΔG, and Gibbs free-energy of activation, ΔG) were determined to provide information on the antioxidant activity as well as to evaluate the contributions of each hydroxyl group to the referred property.
View Article and Find Full Text PDFIn this work, we present a computational study on the antioxidant potential of myricetin 3,4[Formula: see text]-di-O-α-L-rhamnopyranoside (Compound M). A density functional theory (DFT) approach with the B3LYP and LC-ωPBE functionals and with both the 6-311G(d,p) and 6-311+G(d,p) basis sets was used. The focus of the investigation was on the structural and energetic parameters including both bond dissociation enthalpies (BDEs) and ionization potentials (IPs), which provide information on the potential antioxidant activity.
View Article and Find Full Text PDFPrevious research in our group showed that tellurophenes with pinacolboronate (BPin) units at the 2- and/or 5-positions displayed efficient phosphorescence in the solid state, both in the presence of oxygen and water. In this current study, we show that luminescence from a tellurophene is possible when various aryl-based substituents are present, thus greatly expanding the family of known (and potentially accessible) Te-based phosphors. Moreover, for the green phosphorescent perborylated tellurium heterocycle, 2,3,4,5-TeCBPin (4BTe), oxygen-mediated quenching of phosphorescence is an important contributor to the lack of emission in solution (when exposed to air); thus, this system displays aggregation-enhanced emission (AEE).
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