Перегляд за Автор "Mayboroda, Elena"

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2-Acylthioamides in the Biginelli reaction
(2017) Simurova, Natalia; Mayboroda, Elena; Britsun, Vasiliy
Absorption anisotropy studies of polymethine dyes
(2004) Lepkowicz, R.; Przhonska, Olga; Stryland, E.; Slominsky, Yu.; Kachkovski, A.; Mayboroda, Elena; Bondar, Nikolai
The determination of the spectral position of the excited states and orientation of the transition dipole moments of polymethine molecules is experimentally measured using two methods: the steady-state fluorescence anisotropy method, and a two-color polar¬ization-resolved pump-probe method. This novel use of the pump-probe method is described in detail and a comparison to the flu¬orescence method is given. Quantum-chemical modeling on the effects of the bridge structure in the polymethine chromophore on the linear absorption spectrum is also discussed.
Antiviral activity of 1,2,4-triazole derivatives (microreview)
(2021) Simurova, Natalia; Mayboroda, Elena
Today, 1,2,4-triazole derivatives are the preferred structural moieties in the development of new drugs with a wide range of pharmacological activity, as evidenced by several reviews.This is due to the fact that the triazole ring can be considered a bioisostere of an amide, ester, or carboxyl groups. Relatively low toxicity, good pharmacokinetic and pharmacodynamic properties of triazole, its resistance to metabolic degradation are another advantages. In recent years, against the background of the emergence of new viral infections and the lack of effective chemotherapeutic agents for their treatment, the number of studies on the antiviral properties of 1,2,4-triazole derivatives has significantly increased. In the presented review, we focused on current publications devoted to the study of the antiviral properties of compounds containing the 1,2,4-triazole ring. Isosteric analogs of known drugs, as well as new molecules, are considered.
Biginelli reaction – an effective method for the synthesis of dihydropyrimidine derivatives
(2017) Simurova, Natalia; Mayboroda, Elena
A brief review of the publications over the past 5 years devoted to the synthesis of 3,4-dihydropyrimidin-2(1H)-one derivatives using Biginelli reaction is presented. The impact of reaction conditions (solvents, catalysts) on the yield is discussed. New combinations of reagents enabling the synthesis of a wide range of 3,4-dihydropyrimidin-2(1H)-one derivatives with various functional groups are considered.
Chemical resistance of sunflower oil enriched with cumin oil
(2020) Podobiy, Olena; Kovaleva, Svetlana; Zhytnetskyi, Ihor; Mayboroda, Elena
Антиоксидантні властивості олії кмину використовуються для гальмування руйнівних процесів в соняшниковій олії. Досліджено хімічну стійкість соняшникової олії та суміші соняшникової олії та олії кмину. Йодне число олій знижується під час смаження, що означає руйнування подвійних С-С зв’язків залишку жирних кислот у молекулах тригліцеридів. Природні антиоксиданти в олії кмину гальмують утворення вторинних продуктів окиснення під час смаження. Змішування соняшникової олії з олією кмину позитивно впливає на хімічну стійкість масляних композицій в умовах нагрівання. The antioxidant properties ofcumin oil are used to inhibit destructive processes in sunflower oil. The chemical resistanse of sunflower oil and f mixtures of sunflower oil and cumin seed oil was studied. The iodine value of oils decreases during frying, that means a destruction double C-C bonds of fatty acids residue in triglyceride molecules. Natural antioxidants in cumin oil have an inhibitory effect on the formation of secondary oxidation products during frying terms. Blending sunflower oil with cumin oil leads to a positive effect on the chemical resistance of oil compositions under heating conditions.
Development of the method of non-destructive analysis of heavy metals in the raw material that contains carbohydrates
(2016) Mayboroda, Elena; Mazur, Larisa
The effect of specific carbohydrates (matrices) on the results of analysis of microelement in the feedstock has been investigated. Some samples of carbohydrates (mono-, di- and polysaccharides), containing various amounts of salts Cd, Zn, Pb and Hg, have been studied.
Syntheses of 4-aryl-1-R2-6-R1-5-(N-arylthiocarbamoyl)-1,2,3,4-tеtrahydropyrimidine-2-ones (thiones)
(2016) Mayboroda, Elena; Simurova, Natalia
It was found that 2-acylthioacetamides enter into Biginelli reaction with aromatic aldehydes and ureas / thioureas with formation of 4-aryl-1-R2-6-R1-5-(N-Aryl-thiocarbamoyl)-1,2,3,4-tetrahydropyrimidine-2-ones(thiones). When exposed to K3[Fe(CN)6] in alkaline environment, 4-aryl-5-(benzothiazole-2'-yl)-1-R2-6-R1-1,2,3,4-tetrahydropyrimidine-2-ones (thiones), and 4-aryl-1-R2-6-R1-5-(N-Ary1-carbamoyl)-1,2,3,4-tetrahydropyrimidine-2-ones (thions) are unexpected products of interaction. Було з'ясовано, що 2-ацилтіоацетаміди вступають в реакцію Біджинеллі з ароматичними альдегідами і сечовинами/тіосечовинами з утворенням 4-арил-1-R2-6-R1-5-(N-Ar1-тіокарбамоїл)-1,2,3,4-тетрагідропіримідин-2-онів(тіонів). При дії на них K3[Fe(CN)6] в лужному середовищі продуктами взаємодії є не очікувані 4-арил-5-(бензтіазол-2'-іл)-1-R2-6-R1-1,2,3,4-тетрагідропіримідин-2-они(тіони), а 4-арил-1-R2-6-R1-5-(N-Ar1-карбамоїл)-1,2,3,4-тетрагідропіримідин-2-они(тіони). Было установлено, что 2-ацилтиоамиды вступают в реакцию Биджинелли с ароматическими альдегидами и мочевиной/тиомочевиной с образованием 4-арил-1-R2-6-R1-5-(N-арил-тиокарбамоил)-1,2,3,4- тетрагидропиримидидин-2-онов (тионов). При воздействии на них K3[Fe(CN)6] в щелочной среде продуктами взаимодействия являются не ожидаемые 4-арил-5-(бензтиазол-2'-ил)-1-R2-6-R1-1,2,3,4-тетрагидропиримидин-2-оны(тионы), а 4-арил-1-R2-6-R1-5-(N-Ar1-карбамоил)-1,2,3,4-тетрагидропиримидин-2-оны(тионы).
The analisis of interaction monosaccharides with aminoacides in food row by quantum-chemical methods
(2020) Popova, Inna; Mayboroda, Elena; Simurova, Natalia; Karmashov, Oleksandr
The object of research is the products of hydrolysis of the polysaccharide inulin (glucose, fructose) of plant raw materials used for the production of food products for health-improving and prophylactic purposes. The search for optimal conditions for the transformation of polysaccharides in the processes of hydrolytic cleavage into fructose-oligosaccharide products requires a thorough study of both the chemical composition of the raw material and the interaction between the components. This affects both the stability of the initial, intermediate and final products of the hydrolysis of the polysaccharide, and its release from plant materials and the further course of its fragmentation. Literature data indicate that the chemical composition of carbohydrate-containing plant materials, in particular the content of mineral components, has not yet been fully studied and requires additional research and refinement. After all, macro- and microelements in its composition are not only important nutrients, but can also take an active part in the transformation of organic components through complexation at intermediate stages of these processes. In addition, the question of the possible interaction of organic compounds in the composition of food raw materials, in particular biopolymers, which make up a significant part of the mass – carbohydrates and protein compounds, also requires attention. Such interaction under normal conditions has practically not been studied, but it can affect the course of technological processes of processing. The study of intermolecular interac-tions occurring in complex natural systems is often complicated either by the absence of direct (selective) physical and physicochemical research methods, or by the multicomponent chemical composition of the system, or by the complexity of the objects (substances) of the study themselves. This is especially true for natural substances of a polymeric nature – proteins, peptides, poly- and oligosaccharides. Therefore, the work paid special attention to the study of the interaction of these components. The spatial structure of inulin molecules, oligosaccharides and elementary units of these polymers has been investigated using quantum chemical modeling. The distribution of ef-fective charges on carbohydrate atoms is calculated; it directly affects their reactivity. And also quantum-chemical models of the interaction of protein substances of plant materials with carbohydrates in vacuum and in aqueous solutions are created, depending on their dilution.