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Protunkevych O. O., Prysiazhniuk K. O., Rakipov I. M. ADVANTAGES OF CIRCULATION EXTRACTION FOR ISOLATION OF FLAVONOIDS FROM FLORES SOPHORAE JAPONICAE. Актуальні проблеми транспортної медицини / Actual problems of transport medicine / 2019;3(57):108-118. ISSN 1818-9385 DOI http://dx.doi.org/10.5281/zenodo.3465426 http://aptm.org.ua УДК 66.048.5: 577.164.3: 661.12 ADVANTAGES OF CIRCULATION EXTRACTION FOR ISOLATION OF FLAVONOIDS FROM FLORES SOPHORAE JAPONICAE Protunkevych O. O., Prysiazhniuk K. O., Rakipov I. M. Odessa National Polytechnic University Odessa, Shevchenko ave., 1, 65044 E-mail: o.o.protunkevych@opu.ua Summary Phyto-preparations based on extracts from plant raw materials have an important place in modern pharmacy. Medicinal plant Japanese pagoda tree (Sophora japonica), family Fabaceae, contains a rutin, which is a bioactive compound with pronounced antioxidant activity. Rutin drugs have capillary strengthening, anti-inflammatory and anti-edema effects. The raw material base expansion for rutin production is a priority of modern research in the pharmacognosy. It is of interest in-depth study of flavonoids content in Sophora japonica various organs and modern methods optimization of rutin extraction from raw materials. The study aim: circulation extraction optimal conditions determination for a flavonoids complex from Flores Sophorae japonicae, optimal concentration determination of ethyl alcohol for rutin isolation, determination of conditions for flavonoids recrystallization, and also the target product qualitative analysis. Dry Flores Sophorae japonicae crushed to 3-5 mm particles were used for the studies. The rutin was isolated by circulation extraction in a Soxhlet apparatus. 50 %, 70 % and 96 % ethyl alcohol were used to determine the optimum concentration of the extractant. The dynamics of the rutin release at different concentrations of the extractant were investigated. In the experimental extracts, the quantitative content of flavonoids (in terms of rutin) was evaluated by spectrophotometry by the level of aluminum chloride complexation. The extracts were concentrated on a rotary evaporator for crystallization of rutin. The flavonoid precipitates were released from the impurities by recrystallization and subjected to qualitative analysis by TLC, differential spectrophotometry, and mass spectroscopy. Ethanol 70 % exhibited the best flavonoid extraction properties, for complete raw material depletion, the circulation extraction duration was 2 hours 30 minutes. A solvent system of 96 % ethanol-water was used for recrystallization, in the purified flavonoid precipitate the proportion of impurities was about 4 %. In the qualitative analysis, the presence of rutin and quercetin in the experimental sediments was confirmed by TLC, differential spectrophotometry and mass spectrometry. The circulating extraction method is promising to obtain the rutin of Flores Sophorae japonicae, it allows to achieve complete depletion of raw materials and the extractant significant savings. Keywords: japanese pagoda tree flowers, rutin, quercetin, circulating extraction.

Protunkevich О. О., Prisyazhnyuk K. A., Rakipov I. M., Marchenko S. I., Ponomareva L. A. OPTIMAL CONDITIONS FOR SELECTIVE EXTRACTION OF FLAVONOIDS FROM FLORES SOPHORAE JAPONICAE. Актуальні проблеми транспортної медицини / Actual problems of transport medicine / 2019;2(56):132-138. ISSN 1818-9385 DOI http://dx.doi.org/10.5281/zenodo.3251637 http://aptm.org.ua OPTIMAL CONDITIONS FOR SELECTIVE EXTRACTION OF FLAVONOIDS FROM FLORES SOPHORAE JAPONICAE О. О. Protunkevich, K. A. Prisyazhnyuk, I. M. Rakipov, S. I. Marchenko, L. A. Ponomareva Odessa National Polytechnic University E-mail: o.o.protunkevych@opu.ua Summary Rutin and quercetin are part of many phytopreparations with antioxidant and anti-inflammatory effects. Flores Sophorae japonicae contain up to 20 % rutin. The authors investigated the optimal conditions for the selective extraction of rutin and quercetin from Flores Sophorae japonicae with alkyls and alkyl acetates. Flores Sophorae japonicae was harvested according to the requirements of the State Pharmacopoeia of Ukraine. For research, the raw material was ground to particles of 3-5 mm in size. Flavonoids from Flores Sophorae japonicae were isolated with 70 % ethanol, the primary aqueous-alcoholic extract was used for further selective extraction of rutin and quercetin with organic solvents (butanol, ethyl acetate and butyl acetate). The quantitative content of total flavonoids (X %, in terms of rutin) in the extracts was determined by the photometric method according to the levels of complexation with aluminum chloride. In the primary water-alcohol extracts, the content of flavonoids was 0,132 ± 0,06 %. To evaluate the properties of alkyls and alkyl acetates, to extract rutin from primary extracts, a two-phase selective extraction was performed in a system — water-alcohol extract: organic solvent (butanol, ethyl acetate and butyl acetate). The selective properties of solvents were evaluated by the quantitative content of flavonoids in organic phases. For crystallization of flavonoids, organic phases were concentrated using a rotary evaporator. Based on experimental data for butanol, ethyl acetate and butyl acetate, quantitative extraction characteristics were calculated, such as the distribution coefficient (D) and the levels of rutin extraction (R, %). It was determined that butyl acetate showed the most pronounced ability of selective extraction (R = 82.7 %). In the ethyl acetate and butanol phases in the cold, crystallization of flavonoids was observed during the day. The precipitates were studied by TLC, IR spectrophotometry and mass spectrometry. Chromatograms showed spots with yellow-green fluorescence and corresponding Rf = 0.5 (rutin) and Rf = 0.81 (quercetin). In the infrared spectra of flavonoid precipitation, absorption bands characteristic of phenolic and alcoholic hydroxyl groups are visible (lanes 1660, 1610, 1580, 1510, 1460 cm-1) and the “fingerprint” area of 800-1200 cm-1, which confirm the presence of rutin. The mass spectrum of precipitation has a peak 60, which corresponds to the mass of glucose and a peak 302, which confirms the presence of quercetin. It was determined that butanol proved to be the optimal selective extractant of flavonoids. Key words: rutin, quercetin, flavonoids, selective extraction.

Методом мас-спектрометрії з бомбардуванням прискореними атомами в режимі позитивних та негативних іонів вивчена фрагментація ряду RGD-пептидоміме-тиків, які містять фрагмент піперазіну. Встановлені основні напрямки розпаду та аналітичні ознаки досліджуваних сполук., Fragmentation of series RGD-peptidomimetics containing piperazine fragment was studied by positive and negative mode of fast atom bombardment mass spectrometry. Main decay pathways and analytical characters of analyzed compounds were determined.

© 2017 American Chemical Society.Piperidine and N-methylpiperidine hydrates aggregate in liquid aqueous solutions due to hydrogen bonds between hydration water molecules. No such effects occur in the mixtures of the amines with methanol, that supports the idea of active role of water solvent in the aggregation. However, the question of contributions in thermodynamic functions due to specific interactions, van der Waals forces, and the size and shape of the molecules remains open. In the present study, limiting partial molar enthalpies of solution of pyrrolidine, N-methylpyrrolidine, piperidine, and N-methylpiperidine in water and methanol and vice versa were measured and compared with those assessed from theoretically calculated molecular interaction energies using a simple "chemical reaction" model. Nearly quantitative agreement of the enthalpies was achieved for the systems studied, except the amines in water. The latter required an empirical hydrophobic hydration term to be considered. The hydrogen bonds formation and breaking which accompany the mixtures formation leads to considerable excess volumes, while the size of the solute molecules is manifested rather in the compressibility of aqueous solutions. SANS evidenced that aqueous solutions are microheterogeneous on the nanometer-order length scale. The propensity to promote phase separation increases in the order: N-methylpiperidine < N-methylpyrrolidine < piperidine < pyrrolidine.

© 2017 Elsevier B.V. In present work a thermochemistry of hydrogen bond formation of proton acceptors (B) in the medium of linear (N-methylformamide (NMF)) and cyclic (2-pyrrolidone (Py)) amides was studied. The infinite dilution solution enthalpies of nitriles, ketones, esters, ethers and amines in amides were measured at 298.15 K. Enthalpies of hydrogen bonding of proton acceptors in solution linear and cyclic amides were calculated and compared with previously determined the enthalpies of hydrogen bonding of amides in proton acceptor media. The cooperative effects of hydrogen bonding in multi-particle complexes of amides with proton acceptors were evaluated. It was shown that cooperativity coefficients were decreased with increasing the basicity of proton acceptors.

© 2017 Elsevier B.V.In present work thermochemistry of hydrogen bond formation of linear (acetamide (АА), N-methylacetamide (NMA), N,N-dimethylacetamide (DMAA)) and cyclic amides (2-pyrrolidone (Py), N-methyl-2-pyrrolidone (MPY)) in the medium of proton acceptors (B) was studied. Enthalpies of solution of amides in nitriles, ketones, esters, ethers and amines were measured at 298.15 and infinite dilution conditions. Enthalpies of hydrogen bonding of studied solutes with proton acceptor solvents were determined on the basis of experimental data. It was shown that proton donor properties of 2-pyrrolidone are more pronounced than linear amides. Enthalpies of hydrogen bonding of acetamide in proton acceptors are twice more than N-methylacetamide due to formation of 1:2 complexes.

© 2016 Journal of Advanced Pharmaceutical Technology and Research. In this work enthalpies of dissolution in water of polyethylene glycols (PEGs) having an average molecular weight of 1000 and 1400, Pluronic-F127, phenacetin as well as the composites prepared from them were measured using solution calorimetry at 298.15 K. Intermolecular interaction energies of polymer-phenacetin were calculated on the basis of an additive scheme. It was shown that for mixtures with high content of polymer (>90 wt%) Pluronic-F127 has the highest solubilizing effect, while for mixtures with (4-6):1 polymer: phenacetin ratio the best solubilizing agent is PEG-1400. Infrared-spectra showed a decrease of the number of self-associated molecules of phenacetin with increasing of polymer content in the composites. The obtained results enabled us to identify the features of intermolecular interactions of polymers with a model hydrophobic drug and may be used for optimizing the conditions for preparing solid dispersions based on hydrophilic polymers.

© 2016 American Chemical Society.Densities and speeds of sound were measured for binary mixtures of 2-pyrrolidone or N-methyl-2-pyrrolidone with acetonitrile or chloroform at temperatures of (293.15 to 323.15) K and at atmospheric pressure, with uncertainties of 0.5 kg·m-3 and 0.5 m·s-1, respectively. From the measured speeds and densities, isentropic compressibilities and molar excesses of volume, isentropic compression, and thermal expansion were calculated. All of the excesses are negative, which is due to the geometries of the molecules and changes in the hydrogen bonding upon mixing. In the simplest case of the N-methyl-2-pyrrolidone + acetonitrile system, the negative excesses result only from the different sizes of the molecules because the components are incapable of forming either self- or cross-associates. For the other systems, the net effects of the formation and/or dissociation of the hydrogen bonds lead to bigger negative excesses of molar volume and thermal expansion. The negative excesses of compression are probably caused mainly by filling of the gaps between the big lactam molecules with the smaller acetonitrile or chloroform molecules, while the formation of the hydrogen-bonded cross-associates plays a minor role.

© 2016 Elsevier B.V.Enthalpies of dissolution of pyrrole, N-methylpyrrole in proton acceptor solvents and proton acceptors in the medium of pyrrole, N-methylpyrrole were measured. The enthalpies of hydrogen bond of pyrrole, N-methylpyrrole with proton acceptors were calculated from experimental data of solution enthalpy of amines with organic compounds. The hydrogen bond enthalpies of proton acceptors with N- methylpyrrole are equal to zero unlike with pyrrole. The hydrogen bond enthalpies of proton acceptors (B) in pyrrole are significantly lower than the enthalpies of hydrogen bonding of systems of pyrrole-base in the complexes 1:1 due to reorganization effects of pyrrole as solvent. The cooperative effects in multi-particle complexes of pyrrole with bases are negligible.

© 2016 Taylor & Francis Group, LLC.In this research, thermal characteristics and model free kinetics of five different °American Petroleum Institute gravity crude oil samples from different locations were studied using combustion calorimetry and thermogravimetry (TGA) techniques. Higher heating values of crude oils were determined from the combustion calorimetry experiments. It was shown that these values increase with an increase in saturate fraction and °API gravity of studied samples and decrease with an increase in viscosity, aromatics fraction, and resin fraction of crude oils. In thermogravimetry, experiments were performed at 10, 20, and 30°C/min heating rates under an air atmosphere. Thermal characteristics of the samples such as reaction intervals and corresponding peak temperatures, mass loss, and residue of the crude oil samples were also determined. Two different model free kinetic methods, known as Ozawa-Flynn-Wall (OFW) and Kissinger-Akahira-Sunose (KAS), were used in order to determine the activation energy values of the crude oil samples studied.

В случае взаимодействия метил-N-хлор-N-алкоксикарбаматов с трифторацетатом серебра образуются N,N-бис(метоксикарбонил)-N-алкоксиимиды. Исследование строения N,N-бис(метоксикарбонил)-N-метоксиимида с помощью РСА позволяет доказать наличие аномерного эффекта nO(Me)→σ*NX в NXN-метоксисечовинах (X = OAc, Cl, OMe, N+C5H5)., У разі взаємодії метил-N-хлор-N-алкоксикарбаматів з трифторацетатом срібла утворюються N,N-біс(метоксикарбоніл)-N-алкоксиіміди. Дослідження будови N,N-біс(метоксикарбоніл)-N-метоксиіміду за допомогою РСА дозволяє довести наявність аномерного ефекту nO(Me)→σ*N-X у N-X-N-метоксисечовинах (X = OAc, Cl, OMe, N+C5H5).

Ethyl ethers of N-[4-(isoindoline-5-yl)amino-4-oxobutyryl]-D,L-β-substituted-β-alanines were synthesized. Estimation of antiaggregatory activity of the compounds obtained has showed that the compounds possess an oral activity ex vivoin mice with the use of human rich platelet plasma., Синтезовано етилові ефіри N-[4-(ізоіндолін-5-іл)аміно-4-оксобутирил]-D,L-бета- заміщених-бета-аланінів. Вивчення антиагрегаційної активності показало, що отримані сполуки проявляють пероральну активність у дослідах ex vivo на ми­шах з використанням багатої на тромбоцити плазми крові людини.

© 2015 Elsevier B.V. Enthalpies of solution at infinite dilution at 298 K, ΔsolnHA/Solvent, have been measured by isothermal solution calorimetry for 43 and 72 organic solutes dissolved in chlorobenzene and 1,2-dichlorobenzene, respectively. The measured ΔsolnHA/Solvent data, along with published ΔsolnHA/Solvent values taken from the published literature for solutes dissolved in both chlorobenzene solvents, were converted to enthalpies of solvation, ΔsolvHA/Solvent, using standard thermodynamic equations. Abraham model correlations were developed from the experimental ΔsolvHA/Solvent data. The best derived correlations describe the experimental gas-to-chlorobenzene and gas-to-1,2-dichlorobenzene enthalpies of solvation to within standard deviations of 1.5 kJ mol-1 and 1.9 kJ mol-1, respectively. Enthalpies of X-H⋯π (X - O, N, and C) hydrogen bond formation of proton donor solutes (alcohols, amines, chlorinated hydrocarbons, etc.) with chlorobenzene and 1,2-dichlorobenzene were calculated based on the Abraham solvation equation. Obtained values are in good agreement with the results determined using conventional methods.

Copyright © Taylor & Francis Group, LLC. In this study, nonisothermal kinetics and thermal analysis of Siberian and Tatarstan regions crude oils is studied by differential scanning calorimetry (DSC) at different heating rates. DSC curves revealed two reaction regions in the temperature range of 20-600°C, known as low and high temperature oxidation, respectively. Three different kinetic methods (ASTM, Borchardt and Daniels, and Roger and Morris) were used to determine the kinetic parameters of the samples and it was observed that the activation energy values are varied.

© 2015 American Chemical Society. In the paper, results of calorimetric measurements, IR spectra, and calculated ab initio stabilization energies of dimers are reported for binary systems butan-2-one + (methanol, ethanol, propan-1-ol, butan-1-ol, and chloroform). Changes in the total enthalpy of specific interactions due to dissolution of butan-2-one in the alcohols, calculated using equations derived in previous works, are positive. That results from the endothermic breaking of the O-H···O-H bonds not completely compensated by the exothermic effects of formation of the O-H···O - C ones. Moreover, the concentration of nonbonded molecules of butan-2-one is significant even in dilute solutions, as is evidenced by the shape of the C - O stretching vibrations band in the IR spectra. Apart from that, the spectra do not confirm 1:2 complexes in spite of two lone electron pairs in the carbonyl group of butan-2-one capable of forming the hydrogen bonds. The changes in enthalpy of specific interactions are negative for dilute solutions of alcohols and chloroform in butan-2-one and of butan-2-one in chloroform, because no hydrogen bonds occur in pure butan-2-one. The experimental results are positively correlated with the enthalpies estimated from the ab initio energies using a simple chemical reaction approach.

© 2015 Springer Science+Business Media New York. We have studied the effect of the ratio of hydroxyethylidene diphosphonic acid and nitrilotri(methylphosphonic acid) and also polyaminopolyether methylenephosphonate chelating agent additives on scale inhibition in simulated formation water. We show that replacing the water with an aqueous-alcohol solvent lowers considerably the pour point of the reagent without having an appreciable effect on its effectiveness. We have developed a composition that exhibits high effectiveness of scale inhibition for scale composed of calcium carbonate and also calcium and barium sulfates when added at 10-20 mg/L.

© 2014 American Chemical Society. Densities and speeds of sound were measured for binary mixtures of butan-2-one with methanol, propan-1-ol, butan-1-ol, and chloroform at temperatures of 293.15-323.15 K and at atmospheric pressure, with the uncertainties of 0.05 kg·m-3 and 0.5 m·s-1, respectively. The molar excesses of volume, isentropic compression, and thermal expansion were calculated for those systems from the measured speeds and densities and for the mixture of butan-2-one with ethanol from the data reported in the literature. The negative excess volumes for the mixtures with alcohols decrease with the elongation of the hydrocarbon chain, and they eventually become positive for propan-1-ol and butan-1-ol at higher temperatures. That probably reflects the vanishing difference in size of the molecules in the mixture. The excess volume of butan-2-one + chloroform is close to that of butan-2-one + methanol. The excess expansion of butan-2-one + chloroform is negative, and it is positive for butan-2-one + alcohols, while the excess compression isotherms are approximately mirror images of those of the excess expansion. That results probably from the counteracting effects of temperature and pressure on the aggregation due to hydrogen bonds.(Graph Presented).

© 2014 Pleiades Publishing, Ltd. Enthalpies of dissolution at infinite dilution (298.15 K) of aniline, N-methylaniline, and N,N-dimethylaniline in a series of proton-acceptor solvents of different classes of compounds have been measured. The solvation enthalpies have been determined, and its relationship with the anilines structure has been analyzed. Enthalpy of hydrogen bonding in the complexes of aniline (1: 2) and N-methylaniline (1: 1) with the solvents has been calculated. In the case of aniline complexes, negative cooperativity of hydrogen bonding has been revealed, the effect enhancing with increasing the solvent proton-acceptor ability.

© 2014 Pleiades Publishing, Ltd. Enthalpies of dissolution are measured at infinite dilution of nitrogen-containing cyclic (pyrrolidine, piperidine) and aromatic compounds (aniline, N-methylaniline, N,N-dimethylaniline, N-methylimidazole, pyridine, 2-, 3-, 4-methylpyridine, pyrrole, N-methylpyrrole) in chloroform and dichloromethane, and vice versa (T = 298.15 K). The enthalpies of hydrogen bonds in the above systems are calculated. Relationships between resulting thermochemical data and the structure of nitrogen-containing cyclic and aromatic compounds are explored.

Enthalpies of solution at infinite dilution of 53 organic solutes in dichloromethane and 10 organic solutes in 1,4-dioxane were measured using semi-adiabatic solution calorimeter. Enthalpies of solvation for 103 organic vapors and gaseous solutes in dichloromethane and for 116 gaseous compounds in 1,4-dioxane were determined from the experimental and literature data. It is shown that an Abraham solvation equation with five descriptors can be used to correlate the experimental solvation enthalpies within standard deviations of 2.07 and 2.29 kJ mol-1 for dichloromethane and 1,4-dioxane, respectively. The derived correlations provide very accurate mathematical descriptions of the measured enthalpy of solvation data at 298 K, which in the case of 1,4-dioxane span a range of 121 kJ mol-1. Division of the experimental values into a training set and a test set shows that there is no bias in predictions, and that the predictive capability of the correlations is better than 3.5 kJ mol-1. Enthalpies of hydrogen bond formation of proton donor solutes (alcohols, amines, chlorinated hydrocarbons, etc.) with 1,4-dioxane were calculated based on the Abraham solvation equation. Obtained values are in good agreement with the available literature data. © 2013 Springer Science+Business Media New York.

Formamide and its derivatives have a large number of practical applications; also they are structural fragments of many biomolecules. Hydrogen bonds strongly affect their physicochemical properties. In the present work a calorimetric study of formamide and its methyl derivatives was carried out. Enthalpies of solution at infinite dilution of formamide, N-methylformamide, and N, N-dimethylformamide in organic solvents at 298.15 K were measured. The relationships between the obtained enthalpies of solvation and the structure of the studied compounds were observed. Hydrogen-bond enthalpies of amides with chlorinated alkanes, ethers, ketones, esters, nitriles, amines, alcohols, and water were determined. The strength of hydrogen bonds of formamide, N-methylformamide, and N, N-dimethylformamide with proton donor solvents is practically equal. Enthalpies of hydrogen bonds of formamide with the proton acceptor solvents are two times larger in magnitude than the enthalpies of N-methylformamide. The process of hydrogen bonding of amides in aliphatic alcohols and water is complicated. The obtained enthalpies of hydrogen bonding in aliphatic alcohols vary considerably from the amide structure due to the competition between solute-solvent and solvent-solvent hydrogen bonds. Fourier transform infrared spectroscopic measurements were carried out to explain the calorimetric data. Hydration enthalpies of methyl derivatives of formamides contain a contribution of the hydrophobic effect. New thermochemical data on the hydrogen bonding of formamides may be useful for predicting the properties of biomacromolecules. © 2012 Springer Science+Business Media New York.

The measurements of enthalpies of triethylamine and tri-n-butylamine dissolution in aliphatic alcohols and, vice versa, of aliphatic alcohols in amines were carried out. Enthalpies of specific interactions in the studied systems were calculated. The enthalpy of specific interaction determined in the alcohol medium, are significantly less than those obtained at dissolving alcohols in amines. The mechanism of specific interaction of amines with alcohols is discussed. Enthalpies of cooperative hydrogen bonds of tertiary amines with alcohol clusters are calculated. The dependences between the enthalpies of hydrogen bond and the spatial structure of interacting molecules are revealed. © 2010 Pleiades Publishing, Ltd.