Theoretical Characterization by Density Functional Theory (DFT) of Delphinidin 3-O-Sambubioside and Its Esters Obtained by Chemical Lipophilization

Abstract

Anthocyanins are water-soluble phenolic pigments. However, their poor solubility in lipidic media limits their use. This hurdle can be overcome with the lipophilization of anthocyanins, which consists of adding an aliphatic chain to a hydrophilic compound, in order to increase its solubility in lipids. Still, the unspecific chemical lipophilization of anthocyanin-esters produces molecules with different properties from their precursors. In this work, experimental changes of anthocyanin-esters obtained by chemical lipophilization are investigated in silico aiming specifically at observing their molecular behavior and comparing it with their anthocyanin precursor. Thus, the analysis of delphinidin 3-O-sambubioside and its esters employing Density Functional Theory (DFT) methods, such as the hybrid functional B3LYP in combination with the 6-31++G(d,p) Pople basis set, provides the ground state properties, the local reactivity and the molecular orbitals (MOs) of these compounds. Excited states properties were analyzed by TD-DFT with the B3LYP functional, and the M06 and M06-2X meta-GGA functionals. Local reactivity calculations showed that the electrophilic site for all the anthocyanin-esters was the same as the one for the anthocyanin precursor, however the nucleophilic site changed depending localization of the esterification. TD-DFT results indicate that the place of esterification could change the electronic transitions and the MOs spatial distribution.

Chemistry and Pharmacological Actions of Delphinidin, a Dietary Purple Pigment in Anthocyanidin and Anthocyanin Forms

“…Results evaluated by density functional theory demonstrated esterification of the sambubioside (sugar) moiety to yield the most fruitful results. It resulted in high solubility in lipophilic medium without interfering with physical properties of Dp, as lipophilization of the sugar moiety averts the loss of absorbance intensity and its excited states are same with its precursor, Dp-3-S ( 47 ). Glycosides of Dp showed poor stability profile compared to other anthocyanins (Cy, Pt, Pn, and Mv) because of the number of -OH groups in the B ring, whereas methoxy group substitution in ring B augmented the stability as in Pt, Pn, and Mv.…”

Theoretical Analysis of OLED Performances of Some Aromatic Nitrogen-Containing Ligands

“…One of the principal goals of theoretical chemists is to develop new and useful rules and theories to explain the reactivity properties and to predict the directions and mechanisms of chemical reactions [1][2][3][4][5][6][7][8][9][10]. Density Functional Theory (DFT) that was revealed in accordance with this goal uses the electron density to identify the reactivity or stability [11][12][13][14][15][16][17].…”

In silico approach: Anthocyanin derivatives as potential inhibitors of the COVID-19 main protease

“…The combination of several computational techniques used such as molecular docking, and molecular dynamic simulation is expected to be able to provide accurate prediction results through complex calculations [30]. Besides, the quantum mechanics approach using density functional theory (DFT) on small molecules especially anthocyanin derivative molecules shows promising results in molecular modeling [31,32]. Therefore, the selection of an in silico approach is able to offer fast, effective, and accurate alternatives in finding a SARS-CoV2 drug or vaccine.…”