A QSAR study of radical scavenging antioxidant activity of a series of flavonoids using DFT based quantum chemical descriptors – the importance of group frontier electron density

Abstract

In a pursuit of electronic level understanding of the antioxidant activity of a series of flavonoids, quantitative structure-activity relationship (QSAR) studies have been carried out using density functional theory (DFT) based quantum chemical descriptors. The best QSAR model have been selected for which the computed square correlation coefficient r(2) = 0.937 and cross-validated squared correlation coefficient q(2) =0.916. The QSAR model indicates that hardness (η), group electrophilic frontier electron density (F(E)(A)) and group philicity (ω(B)(+)) of individual molecules are responsible for in vitro biological activity. To the best our knowledge, the group electrophilic frontier electron density (F(E)(A)) has been used for the first time to explain the radical scavenging activity (RSA) of flavonoids. The excellent correlation between the RSA and the above mentioned DFT based descriptors lead us to predict new antioxidants having very good antioxidant activity.

Computational Studies of Free Radical-Scavenging Properties of Phenolic Compounds

“…In other cases, when % inhibition data at a single concentration are reported for stoichiometric assays of polyphenols, the insufficiency in the concentration of the radical reactant is masked [ 141 , 142 ]. In this way the data from assays designed as (almost) "all-or-none" binary classification tests are not treated in QSAR modelling as such [ 143 - 145 ], thus producing activity cliff-bearing models [ 29 , 146 ].…”

Crystal Structure, Hirshfeld Analysis and DFT Study of 6,7-Dimethoxy-3-[(5-Chloro-1,3,3-Trimethylindolin-2-Ylidene)Methyl]Isobenzofuran-1(3h)-One

“…compared to the reported phthalide derivatives. Thus, suggested that our compound has better or higher biological activity, as it has been reported that small energy gap can lead to high anti-oxidant activity and good inhibition corrosion efficiency (Bentiss et al 2003;Sarkar et al 2012).…”

In silico structure‐based design of GABAB receptor agonists using a combination of docking and QSAR

“…Using the above‐mentioned molecular descriptors, the first QSAR was attempted with all the study compounds. Models with relatively good Q 2 and R 2 values were found; however, two outliers were identified (compounds 4 and 6 ); according to Sarkar, Middya, & Jana (), if the difference in the calculated and experimental activity values of one molecule exceeds three times the standard deviation, it can be considered as an outlier. The two outliers were removed, and the analysis was carried out again, which led to the generation of several good models.…”