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Article
Structure and Antiradical Activity of Hydrogen-Bound Complexes of Protocatechoic Acid with Monosaccharides in Aqueous Media
It was found by the photocolorimetry method that binary compositions of protocatechic acid with monosaccharides (galactose, mannose) exhibit a pronounced antiradical synergistic effect in reaction with 2,2ʹ-di...
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Article
Effect of Solvent Polarity on the Synergistic Effects in Radical Oxidation of Natural Phenols in the Presence of Mono- and Oligosaccharides
As shown by photocolorimetry, NMR spectroscopy, and calculations based on the density functional theory, the synergistic antiradical effect of binary formulations of vegetable phenols with mono- and oligosacch...
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Article
Regression-Classification Algorithm for Screening of Antiradical Activity of Flavonoids and the Related Structures
A regression-classification algorithm for screening the antiradical activity of flavonoids and the related structures in the media with physiological pH and a specialized kinetic reaction scheme have been prop...
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Article
Two-Variable Predictive Model of the Antiradical Activity of Hydroxybenzoic Acids in Media with Physiological pH
A regression–classification algorithm to screen natural hydroxybenzoic acids for antiradical activity in media with physiological pH was proposed. The algorithm is based on a combination of descriptor–activity...
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Article
Mechanism of the Antiradical Action of Natural Phenylpropanoids in Nonionizing Polar Media
The kinetics and mechanisms of the reactions of some natural phenylpropanoids from the group of hydroxycinnamic acids with the stable radical 2,2'-diphenyl-1-picrylhydrazyl in polar nonionizing media were stud...
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Article
Phenolcarboxylic Acids in the Reaction with Electrogenerated Hydroperoxyl Radical
Using the chronovoltammetric method, it has been shown that the reduction of oxygen on a mercury electrode in the presence of phenolcarboxylic acids in an acidic medium occurs as reversible electrode process f...
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Article
Predictive Model of the Relationship of the Antiradical Activity and the Ionization Potential of Molecules and Ions of Flavonoids
A relationship between the antiradical activity of flavonoids and the molecular descriptors related to the mechanism of their antiradical action was determined by single-variable linear regression analysis in ...
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Article
Factor Analysis of the Relationship of the Chemical Structure and Anti-Radical Activity of Natural Phenols
Using multiple linear regression analysis, a relationship has been established between the antiradical activity of various classes of natural phenols and descriptors of their electronic structure in the form o...
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Article
Proton Coupled Electron Transfer in the Reaction of Hydroxybenzenes with Hydrazyl Radical in Aqueous Media
Possible electron transfer mechanisms have been studied for the reaction of 2,2′-diphenyl-1-picrylhydrazyl with a number of natural hydroxybenzenes in aqueous buffer solutions at pH = 2–9 using the methods of ...
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Article
Spectrokinetic Studies of the Products of Conversion of Natural Phenols in Radical Reactions
Fourier-transform IR and NMR spectroscopy are used to show that, in the reaction with 2,2'‑diphenyl-1-picrylhydrazyl radical, the secondary products of natural phenol conversion are dimeric compounds formed by...
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Article
Transition State Structure and Mechanism of the Reaction of Hydroxybenzenes with N-Centered Radical in Non-Ionizing Media
Experimentaly and theoretically, using the method of density functional theory, the structure of 2,2'-diphenyl-1-picrylhydrazyl radical and the mechanism of its reaction with di- and trihydroxybenzenes in non-...
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Article
Determination of Relative Rate Constants for Reactions of 2,2’-Azobis-(2-Amidinopropane) Dihydrochloride Peroxyl Radicals with Dihydroxybenzenes and Their Derivatives
An iodometric method for determining the antiradical activity (ARA) of dihydroxybenzenes in the reaction with 2,2′-azobis-(2-amidinopropane) (AAP) peroxyl radicals (rOO• ) in conditions close to those obtaining i...
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Article
The effect of the medium polarity on the mechanism of the reaction of hydroxybenzenes with hydrazyl radical in aprotic solvents
Mechanisms of the reaction of di- and trihydroxybenzenes with 2,2′-diphenyl-1-picrylhydrazyl (stable radical) in aprotic media of different polarity have been elucidated by experimental and quantum-chemical me...
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Article
The Antiradical Activity of Plant Tannins in Reactions with Electrochemically Generated Reactive Oxygen Species
The activities of tannins from various plant extracts prepared by electroextraction were studied in a reaction with oxygen radicals during cathodic electroreduction of oxygen in an aqueous medium on a drop**...
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Article
Natural phenolic compounds in the reaction with a nitrogen-centered radical in an aprotic solvent
Kinetics and mechanism of the reaction of vegetable phenols (PhOH) with 2,2′-diphenyl-1-picrylhydrazyl radical (DPPH•) in a polar aprotic solvent, dimethyl sulfoxide, were studied. The reaction of natural phen...
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Article
Dissociation constants of phenol in the presence of polyoxyethylene sorbitan monooleate
Potentiometric titration was used to determine the dissociation constants of di- and trihydroxybenzenes in a 1: 1 deoxygenated water-ethanol system at a temperature of 293 ± 1 K in the presence of a nonionogen...
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Article
Reactions of unsubstituted hydroxybenzenes with 2,2-diphenyl-1-picrylhydrazyl in the system water-aprotic solvent
The reactivity of natural unsubstituted di- and trihydroxybenzenes in the reaction with a stable free radical 2,2-diphenyl-1-picrylhydrazyl in a mixed solvent water-dimethyl sulfoxide (2:1) was investigated. K...
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Article
Antiradical activity of fruit juices in reactions with diphenylpicrylhydrazyl
The antiradical activity (ARA) of fresh squeezed juices and those reconstituted from concentrate was examined in reactions with diphenylpicrylhydrazyl (DPPH). Fresh squeezed juices contain a higher amount of p...
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Article
Optimization of conditions for the extraction of antioxidants from solid parts of medicinal plants
The extraction of phenolic antioxidants from solid plant raw materials (bark and roots) under the action of an electric current was studied. A relationship between the amount and antioxidant activity of extrac...
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Article
Electric-field-assisted extraction of antioxidants from bearberry leaves
Conditions for improving the extraction of substances with antioxidant properties from bearberry (Arctostaphylos Adams) leaves have been studied. It is established that the natural antioxidants are most completel...
