Distilled Off Research Articles

CYCLOALKYLATION OF PARA-CHLOROPHENOL WITH 1-METHYL-CYCLOALKENES IN THE PRESENCE OF A ZEOLITE-CONTAINING CATALYST

The results of alkylation reactions of para-chlorophenol with 1-methylcyclopentene and 1-methylcyclohexene in the presence of zeolite-containing catalyst Seokar-2 (TU38-101483-77) are presented in the paper. Para-chlorophenol (PCP) interacted with 1-methylcycloalkenes on a laboratory batch setup. The reaction products were separated from the catalyst by hot filtration (40-50 °C) and undergone to distillation. Methylcyclene was distilled off at atmospheric pressure, then unreacted para-chlorophenol and the target reaction product were isolated under vacuum (10 mm Hg). Optimal conditions ensuring maximum yield of 2-cycloalkyl-4-chlorophenols were determined by studying effect of temperature, reaction time, molar ratio of PCP to 1-methylcycloalkenes, and amount of catalyst on the yield and selectivity. The reaction temperature was varied from 80 to 140 °C, duration of the experiments was from 2 to 8 h, molar ratio of PCP to 1-methylcycloalkenes was from 2:1 to 1:2 mol/mol, amount of catalyst was from 5 to 15% mas. It resulted in determining of the optimal conditions for alkylation reaction of para-chlorophenol with 1-methylcyclopentene and 1-methylcyclohexene in the presence of the zeolite-containing catalyst Seokar-2: reaction temperature 110-120 °C, duration 4-6 h, molar ratio of PCP to 1-methylcycloalkenes 1:1, catalyst amount 12-15% (on the taken PCP). These conditions allow having 68.2-73.6% yield of theory for 2-cycloalkyl-4-chlorophenols for the taken PCP, and 89.3-91.8% of selectivity for the target product. The physicochemical properties, elemental composition and structure were determined by 1H NMR and IR spectroscopy after separation of the target products from alkylate by distillation.

Antibacterial, Antifungal and Antiviral Activities of Euphorbia Greenwayi var. Greenwayi Bally & S. Carter

The interest in many traditional natural products is increasing. Natural products continue producing bioactive agents owing to the remarkable available chemical diversity. They were evaluated as prospective therapeutic candidates for the treatment of human and animal infectious diseases. Euphorbiaceae, the spurge family, holds a significant place in the domain of plant families, with scientific evidence of antiviral, antibacterial, anticancer, cytotoxic and antitumor properties. In this regard, the current study intends to investigate the antibacterial, antifungal, antiviral and cytotoxic properties of Euphorbia greenwayi var. greenwayi Bally & S. Carter. The dried aerial parts of E. greenwayi var. greenwayi Bally & S. Carter were used, then extracted with 70% ethanol, solvent was distilled off till dryness. The antimicrobial activity of the extract and both MIC and MBC were evaluated against one strain of Gram-positive bacteria: Staphylococcus aureus ATCC9144; four strains of Gram-negative bacteria: Klebsiella pneumonia ATCC10031, Escherichia coli ATCC10536, Salmonella typhi ATCC14028, Pseudomonas aeruginosa ATCC9027and yeast: Candida albicans ATCC10231. The antiviral activity of hydroalcoholic extract against Rotavirus infection was determined as well as the cytotoxic properties. The antibacterial examination revealed potential activity of the hydroalcoholic extract against all tested species with the inhibition zone ranged from 14.7 to 29.7 mm. The highest activity was against S. aureus and C. albicans. MIC and MBC results proved that the extract is potentially bacteriostatic and bactericidal agents against both Gram-positive and Gram-negative bacteria and against the tested yeast. Also, the extract has the ability to prevent Rotavirus attachment with the cell host. This research revealed that the hydroalcoholic extract of aerial parts of E. greenwayi var. greenwayi Bally & S. Carter has significant antimicrobial potential that can be implemented in different pharmaceutical formulations.

Characteristics of the Main- and Side-Stream Products of Microwave Assisted Torrefaction of Lignocellulosic Biomass of Different Origination

In this paper, the yields and composition of solid and condensable products that were obtained by microwave-assisted torrefaction of softwood, wheat straw, and peat fuel pellets, defined as main- and side-stream torrefaction products, were studied. The torrefaction process, at temperatures varied in the range of 200–300 °C, was performed using a laboratory-scale torrefactor of original construction. Water-enriched fractions were distilled off from condensable products to isolate tar fractions, the fuel characteristics of which were compared with those of solid fractions. Py-GC/MS/FID, GC/MS/FID, thermal analysis, elemental analysis, and wet chemistry methods were used to characterize the main- and side-stream torrefaction products, with a focus on their valorization according to the biorefinery approach. The simultaneous development of the destruction and condensation processes in lignocarbohydrate complexes during microwave treatment leads to an increase in the relative portion of aromatic compounds in torrefied biomass, increasing the higher heating value (HHV) of the solid fractions. The increase up to 60% of the heat amount that was liberated due to the thermal oxidative conversion of solid fractions vs. that of the non-treated ones was established by DSC tests. The heat that was liberated by the combustion of the tar fractions was much lower than that of solid fractions, which was explained by the composition of tars, influencing their thermal conversion.

Изучение кинетических закономерностей и механизма реакции циклоалкилирования фенола с 1-метилциклопентадиеном

The article presents the results of the reaction of phenol with 1-methylcyclopentadiene in the presence of the KU-23 catalyst. Cycloalkylation of phenol have been carried out in a batch laboratory installation. After the reaction, the alkylate is separated from the catalyst and rectified. Firstly, during rectification at atmospheric pressure MCP and phenol that did not enter into the reaction were distilled off (up to 200° C), and then, under vacuum (666.5 Pa) the target reaction product was isolated and its purity and physicochemical parameters were determined. The kinetic regularities of the reaction were studied, and the probable mechanism of its occurrence was established. A kinetic model of the phenol cycloalkylation reaction, consisting of a system of differential equations, that describes the change in the concentration of the initial substances and reaction products over time has been developed. The kinetic constants of differential equations were estimated using a modified random search method with automatic step selection. For this purpose, the developed package of applied programs was used. The orders, activation energies, and rate constants of individual stages are determined. It is shown that the proposed model adequately describes the experimental data.

Изучение химического состава надземной части щавеля приморского (Rumex maritimus L.) методом высокоэффективной жидкостной хроматографии

Introduction. Golden dock (Rumex maritimus L.) is a poorly studied annual plant from the buckwheat family (Polygonaceae Juss.), used by the peoples of South-East Asia to treat a number of diseases. The methanol extract of golden dock has several beneficial properties, including antibacterial activity. At the same time, the chemical composition of the plant is studied fragmentarily. Aim. To determine the qualitative composition of the aerial part of golden dock by high-performance liquid chromatography (HPLC). Materials and Methods. The dried aerial part of the plant at the stage of flowering and the beginning of fruiting was crushed and extracted with 95% ethanol. Ethanol was distilled off, and the extraction was treated sequentially with chloroform, ethyl acetate and n-butanol. We analyzed the obtained fractions and the aqueous residue of ethanol extraction after removal by reversed-phase HPLC. Compounds were identified using standard samples and literature data on the spectral characteristics of substances. Results. Phytochemical analysis of the aerial part of golden dock by reversed-phase HPLC showed the presence of such substances as anthraquinones, flavonoids, stilbenes, phenolic acids. In the chloroform fraction, anthracene derivatives of emodin, chrysophanol, fiscion, isochrysophanol, the flavonoid vogeletin were identified; in the ethyl acetate fraction – phenolic acids: gallic, syringic, p-coumaric, ferulic, trans-stilbene derivative resveratrol, as well as the flavonoids rutin and quercetin; in the butanol fraction – caffeic acid and catechin; in the aqueous residue – epigallocatechin-3-gallate and epicatechin-3-gallate.

HEPATOPROTECTIVE ACTIVITY OF THE WHOLE PLANT OF NEPTUNIA PROSTRATA L. IN CARBON TETRACHLORIDE INDUCED RATS

Objective: The aim of this study is to investigate the hepatoprotective activity of the whole plant of Neptunia Prostrata L.
 Methods: The whole plant was collected and identified as Neptunia Prostrata L. The collected plants were shade dried and pulverized to fine powdered of particle size (#) 40. It was then defatted with petroleum ether for 24 hour and soaked with methanol and ethanol, respectively. The extracts was filtered and distilled off using a rotary evaporator. The phytochemical screening of the extracts was carried out and thin layer chromatography study was also done. Acute toxicity study and in vivo hepatoprotective activity of the methanolic extract using CCL4 (carbon tetra chloride) induced model was investigated.
 Results: The phytochemical screening revealed the presence of alkaloids, glycosides (saponins), flavonoids, tannins, carbohydrates, proteins, phenolic, steroids and terpenoids. Thin-layer chromatography of the methanolic and ethanolic extracts with their fractions using different solvents were performed by taking petroleum ether and ethyl acetate (2:8) as mobile phase system and were able to observe the presence of many spots. Oral administration of methanolic extract of Neptunia prostrata at doses till 2000 mg/kg was found safe and shows good hepatoprotective activity by showing decreased levels of serum SGOT (serum glutamate oxaloacetate transaminase), SGPT (serum glutamate pyruvate transaminase) and ALP (alkaline phosphatase) when compared with the standard drug silymarin.
 Conclusion: The preliminary phytochemical screening of the methanol and ethanolic extract shows phytoconstituents such as flavonoids, triterpenoids, tannins, saponins, alkaloids and chromatographic studies indicates the presence of several components in varying abundance. The decrease of serum bilirubin level by the methanolic extract of the plant shows hepatoprotective activity. It has confirmed the traditional claim for its use in the treatment of jaundice.

Pentaphosphaferrocene-mediated synthesis of asymmetric organo-phosphines starting from white phosphorus

The synthesis of phosphines is based on white phosphorus, which is usually converted to PCl3, to be afterwards substituted step by step in a non-atomic efficient manner. Herein, we describe an alternative efficient transition metal-mediated process to form asymmetrically substituted phosphines directly from white phosphorus (P4). Thereby, P4 is converted to [Cp*Fe(η5-P5)] (1) (Cp* = η5-C5(CH3)5) in which one of the phosphorus atoms is selectively functionalized to the 1,1-diorgano-substituted complex [Cp*Fe(η4-P5R′R″)] (3). In a subsequent step, the phosphine PR′R″R‴ (R′ ≠ R″ ≠ R‴ = alky, aryl) (4) is released by reacting it with a nucleophile R‴M (M = alkali metal) as racemates. The starting material 1 can be regenerated with P4 and can be reused in multiple reaction cycles without isolation of the intermediates, and only the phosphine is distilled off.

Synthesis and research of polyfunctional silicon-containing amines – new promoters of adhesion

Currently, in order to obtain high-tech hybrid products, modern adhesives have high requirements for creating strong joints between dissimilar materials. It is known that adhesion depends on the compatibility of the adhesives with the surfaces of the materials. Amine compounds are the main hardeners for epoxy compositions. That is why, in this article, we synthesized silicon-containing amines based on polyfunctional aminoalkoxysiloxanes for epoxy compositions. Aminoalkoxysiloxanes were prepared by the interaction of 3-aminopropyltriethoxysilane with monoethanolamine in nitrogen at atmospheric pressure in the presence of a binary antioxidant and catalytic amounts of an alkali metal alcoholate. During the reaction in a homogeneous phase, the reaction mixture was heated to a temperature of 100-110 °C and distilled off to 90% of ethanol from the theoretically calculated amount. Further, the reaction was carried out at a reduced temperature of 10-20 mmHg pressure until the release of alcohol stops. At the same time, gravimetric control was carried out and the refractive index of the reaction mixture was measured. As a result, aminoalkoxysilanes were obtained in the form of light-yellow oily liquids. The structure of the obtained compounds was investigated by IR spectroscopy on an FSM-1202 Fourier spectrophotometer and 1H NMR spectroscopy on a high-resolution BrukerWM-250 NMR spectrometer. It was found that under the selected synthesis conditions, aminopropyltri-(2-aminoethoxy)silane is obtained with the highest yield of 97.6% at a molar ratio of 3-aminopropyltriethoxysilane AGM-9 with monoethanolamine 1:3.

Синтез и исследование полифункциональных кремнийсодержащих аминов в качестве промоторов адгезии эпоксиаминных компаундов

At present, in order to obtain high-tech hybrid products, high demands are placed on modern adhesives for creating durable joints between dissimilar materials. It is known that adhesion depends on the compatibility of the adhesives with the surfaces of the materials. For epoxy compositions, amine compounds are the main hardeners. In this regard, in the presented work, silicon-containing amines were synthesized based on polyfunctional aminoalkoxysiloxanes for epoxy compositions, the strength of attachment of which to various metal substrates was studied using these adhesion promoters. Aminoalkoxysiloxanes were prepared by reacting 3-aminopropyltriethoxysilane with monoethanolamine in nitrogen at atmospheric pressure in the presence of a binary antioxidant and catalytic amounts of an alkali metal alcoholate. To carry out the reaction in a homogeneous phase, the reaction mixture was heated to a temperature of 100-110 °C and distilled off to 90% of ethanol from the theoretically calculated amount. Further, the reaction was carried out at a reduced temperature of 10-20 millimeter of mercury pressure until the release of alcohol stops. At the same time, gravimetric control was carried out and the refractive index of the reaction mixture was measured. As a result, aminoalkoxysilanes were obtained in the form of light-yellow oily liquids. The structure of the obtained compounds was investigated by IR-spectroscopy on a Fourier spectrophotometer FSM-1202 and 1H NMR-spectroscopy on a high-resolution BrukerWM-250 NMR-spectrometer. It was found that under the selected synthesis conditions, aminopropyl-tri-(2-aminoethoxy)silane is obtained with the highest yield of 97.6% at a molar ratio of 3-aminopropyltriethoxysilane (AGM-9) with monoethanolamine 1: 3. The obtained compounds were used in the composition of epoxy compounds in order to improve their physical and mechanical properties. The adhesion properties of epoxy compositions based on ED-22 epoxy resin and isophorone diamine were studied using synthesized polyfunctional aminoalkoxysiloxanes as adhesion promoters. It was found that the most effective adhesion promoter is aminopropyl-tri-(2-aminoethoxy) silane.

Новые амидные производные хлорина е6 с фрагментами 1,3-диаминопропана

In this work, we studied the interaction of methylpheophorbide a with 1,3-diaminopropane and proposed a simple method for the synthesis of chlorin e6 derivatives with one, two, and three amino groups on the periphery of the macrocycle. It is shown that, when methylpheophorbide a acts on 1,3-diaminopropane in a medium of chloroform or methylene chloride, the exocycle opens chemically selectively and chlorin e6 13-amide derivative of with an amino group attached by a spacer of three methylene groups forms (chlorin e6 13-N-(3-aminopropyl)amide 15,17-dimethyl ether). By the action of 1,3-diaminopropane on chlorin e6 13-N-(3-aminopropyl)amide 15,17-dimethyl ether at room temperature without solvent, chlorin e6 13,17-N,N'-(3-aminopropyl) can be chemically selective diamide 15-methyl ether and chlorin e6 13,17-N,N',N''-(3-aminopropyl)triamide with two and three amino groups, respectively. The preparation of di- and triaminochlorins can be carried out both from chlorin e6 13-N-(3-aminopropyl)amide of 15,17-dimethyl ether, and directly from methylpheophorbide a without isolation of the intermediate monoaminochlorin. In the latter case, after the methylpheophorbide a exocycle is opened with 1,3-diaminopropane in chloroform or methylene chloride medium, the solvent is distilled off from the reaction mixture and the resulting monoaminochlorin reacts with the 1,3-diaminopropane present in the mixture without solvent. The structure of the obtained mono-, di, and triaminochlorins is confirmed by IR and NMR spectroscopy.

ХИМИЧЕСКИЙ СОСТАВ ОРГАНИЧЕСКОГО ВЕЩЕСТВА КОРЫ ДУБА ОБЫКНОВЕННОГО (ЧЕРЕШЧАТОГО) (QUERCUS ROBUR L, СЕМЕЙСТВО БУКОВЫЕ – FAGACCAC) (СООБЩЕНИЕ III – ХЛОРОФОРМНЫЙ ЭКСТРАКТ)

This report presents the results of chromatography-mass spectrometry of a chloroform extract obtained after preliminary sequential exhaustive extraction of the bark of ordinary oak (petiole) n-hexane and toluene. The purpose of the study is to significantly expand the range of compounds that determine the composition of the organic matter of the bark of ordinary oak (petiole). Materials and research methods. The dried raw material is ground to a powder in a porcelain laboratory mill, which is then subjected to exhaustive sequential extraction with n-hexane and toluene at boiling points. Then, the solid residue was dried to constant weight in a vacuum oven, and then extraction was carried out with chloroform at its boiling point. Extraction with chloroform was completed when the refractive index was reached equal to its initial value, after which chloroform was distilled off in a vacuum rotary evaporator to obtain a dark brown oily residue.
 Thus, we can conclude that the pharmacological effect of the chloroform extract of ordinary oak bark (petiolate) will be determined by the presence of significant amounts of sterols, hydrocarbons, which are dominated by arenes, alkenes and cycloalkanes, esters formed mainly by dicarboxylic acid (Oxalic acid).

Chemical Compostions of Essential Oils and Antimicrobial Activity of Hyptis suaveolens (L.) Poit. (Lamiaceae) from Vietnam

Aims: This present study described the chemical constituents and antimicrobial activity of essential oils hydrodistiled from the leaves and flowers of Hyptis suaveolens (L.) Poit.
 Study Design: This research was designed to accommodate different stages such as collection of authentic sample of Hyptis suaveolens, obtain essential oil by hydrodistillation, chemical analysis of the oil samples by gas chromatography (GC) and gas chromatography coupled with mass spectrometry (GC/MS) and screening of the essential oils for antimicrobial activity.
 Place and Duration of Study: School of Natural Science, Vinh University, Vinh City, Nghệ An Province, Vietnam, between August and December 2018.
 Methodology: The leaves and flowers of H. suaveolens used for this study were gotten from Đồng Văn Commune, Pù Hoạt Nature Reserve, Vietnam. The collection was done in December 2018. Essential oils were distilled off using hydrodistillation method according to established procedure. The determination of antimicrobial efficacy of essential oils of H. suaveolens will be achieved by the method of microdilution broth susceptibility assay. The minimum inhibitory concentration (MIC) and IC50 were evaluated accordingly.
 Results: The major compounds in the oil were b-caryophyllene (31.1% and 33.7%), caryophyllene oxide (17.6% and 3.9%), phytol (9.9% and 2.7%) and a-humulene (6.7% and 6.6%), respectively. The leaf oil displayed strong antimicrobial activity against Enterococcus faecalis ATCC299212, Bacillus cereus ATCC14579 and Candida albicans ATCC10231 with minimum inhibitory concentrations (MIC) of 16.0, 32.0 and 16.0 µg/mL respectively, while the IC50 values were 5.78, 9.35 and 6.78 µg/mL, respectively. The flower oil showed activity towards the same organisms with MIC values of 64.0, 64.0 and 16.0 µg/mL, respectively; with IC50 values of 20.45, 26.78 and 6.78 µg/mL, respectively. Both essential oils exhibited moderate activity towards Staphylococcus aureus ATCC25923 with MIC of 256.0 µg/mL.
 Conclusion: The results are indication of the potential of H. suaveolens essential oils as source of antimicrobial agents.

THE STUDY OF PHENOLIC COMPOUNDS OF THE BERRIES OF THREE SPECIES OF PLANTS OF THE GENUS VACCINIUM, GROWING IN THE KHANTY-MANSI AUTONOMOUS AREA

The chemical composition of polyphenolic compounds of cranberry fruits (Vaccinium oxycoccus L.), blueberries (Vaccinium myrtillus L.) and lingonberries (Vaccinium vitis-idaea L.), growing in the Surgut region of the Khanty-Mansiysk Autonomous Okrug – Ugra, was first studied. Fresh berries were extracted five times with an 80% aqueous-alcoholic mixture at room temperature. The obtained extracts were combined, filtered, and the solvent from the filtrate was distilled off under vacuum on a rotary evaporator. The composition of the obtained extracts by HPLC identified 15 glycosides of anthocyanidins, as well as 30 phenolic compounds related to hydroxybenzoic and hydroxycinnamic acids, flavonols, catechins and procyanidins. The phenolic compounds were identified in accordance with the retention times and absorption spectra of the corresponding analytical standards. The main phenolic compound of cranberry berry extract is chlorogenic acid. The increase in the polyphenol content in the series was established: cranberries–lingonberries– blueberries. Our data on the whole in terms of the content of polyphenols and antioxidant activity are comparable with the results of a study of cranberries and blueberries from the Alaska region, not significantly differing in the content of anthocyanins and individual flavones. Significant differences in phenolic components are revealed when comparing our data with data on cranberries and cranberries from the regions of northern and eastern Europe (Poland, Belarus, Norway). The quantitative differences found for individual polyphenols are likely to be related to geographic and local environmental conditions. The high content of polyphenols in the berries we studied suggests the possibility of using them as pharmaceutical raw materials.

Preparation of a Composite Material from Palm Oil Fiber and an Ecological Emulsion of Expanded Polystyrene Post-Consumption

The overproduction of plastics and the wide availability of natural fibers that become a source of contamination before ending their useful life, in a context of environmental crisis, has led researchers to study how to integrate them into the production of biocomposites. For this project, the development of a composite material that integrated expanded post-consumer polystyrene (EPS) and palm fiber (OPEFB) was proposed. OPEFB fibers were obtained from palm growers in the region, being processed by drying, grinding and sieving with a particle size (Mesh of 30,40, 50, 60 and 70). To obtain the solvent of the EPS, a volume of orange essential oil (Citrus sinensis) was distilled off by steam and the amount of d-limonene present was quantified using the gas chromatography technique coupled to mass spectrometry. Subsequently, the EPS was dissolved and a solubility of 0.5 g / mL was reached and with this volume a 1: 2 water / EPS-Citrus Sinensis emulsion was formulated which was characterized using the optical microscopy technique and two dyes of different polarity to observe its affinity with both phases, allowing it to be classified as a W/O type macroemulsion. The agglomerates were made by a process of molding, pressing and heating for baking. All the above parameters were kept constant and only the fiber size varied. The tests of resistance to compression and hardness showed that, to a smaller fiber size, less hardness, resistance to compression and stiffness, so the specimens made with mesh fibers (Mesh) No. 40 showed better performance in mechanical tests.

Свойства сополимеров бутилакрилата с винилизо-бутиловым эфиром, полученных с использованием инициирующей системы триэтилборан – кислород компенсационным способом

The synthesis of copolymers of butyl acrylate with vinyl isobutyl ether was carried out by adding the active monomer to the excess of the comonomer when boiling in the presence of triethylborane. An organoelement co-initiator was isolated from a complex with hexamethylenediamine in a solution of vinyl butyl ether, with addition of methacrylic acid in an amount proportional to the amount of amine in moles, together with butyl acrylate. As a co-initiator of triethylborane, air oxygen was present in the reaction mixture at boiling of the vinyl butyl ether. The introduction of butyl acrylate was completed within 20 minutes. After that, the process was stopped (in the first series of samples), or else the reaction mixture was thermostated for another 40 minutes (in the second series of samples). At the end of polymerization, the liquid fraction was distilled off. The copolymer samples were isolated by removing the monomers under vacuum, and their conversion was evaluated gravimetrically by the dry residue. Molecular weight parameters for the samples were determined by gel permeation chromatography. The composition of the copolymers was determined by IR spectroscopy using a calibration graph based on the area of the characteristic peak. The obtained data suggest that during the copolymerization of butyl acrylate with vinyl isobutyl ether, a macromolecular chain is formed along two centers: oligomeric and low-molecular. The formation of an oligomer along with a low-molecular polymer, usually formed under such conditions at traditional radical initiation, is explained by the presence of boroxyl radicals in the reaction mixture, which are known in the oxidation of trialkylboranes. Due to the interaction of the latter with initiating R• or RO• radicals, which are also observed during the oxidation of trialkylboranes, or with oligomeric growing radicals, a growth center of the polymer chain is formed by the mechanism of reversible inhibition with a very low degree of polymerization. Continued thermostating of the reaction mixture after dosing butyl acrylate with methacrylic acid leads to a shift in the oligomeric mode in the direction of increasing the value of molecular weight; accordingly, M n increases and M w /M n decreases. This occurs because the copolymerization process continues in the absence of the initiator due to the reversible inhibition reaction. The time-dependent conversion rate is characterized by an abrupt decrease in the conversion rate by 40–60 %, which is also associated with the transition of the method of forming macromolecules with the predominantly high-speed bimolecular break to a process following the reversible inhibition mechanism according to the scheme, which runs at a much lower rate. The composition of the copolymers is characterized by a slightly higher equimolar content of acrylate, with a higher value of the relative activity of vinyl isobutyl ether, paired with butyl acrylate during copolymerization (r BA = 1.45 ± 0.07; r VBE ≈ 0; r BA = 5.2 ± 1.5; r ViBE ≈ 0).

Development of Composition and Technology of Resveratrol Capsules

Introduction. Resveratrol is of scientific interest as a substance with a wide range of biological effects. However, its low bioavailability leads to limited use when administered orally. Therefore, the objective was to increase its solubility using various groups of excipients and create a solid dosage form. As a result of research, a group of twins was selected and the technology of manufacturing capsules containing 40 mg of resveratrol as a active substance was developed.Aim. The development of a solid dosage form – capsules containing resveratrol, tween 80 as a solubilizer and other excipients.Materials and methods. A composition with resveratrol, tween 80, glycerin, citric and ascorbic acids as stabilizers was developed. Methanol was used as a common solvent and was distilled off after complete dissolution of all components and obtaining a homogeneous mass. After adding olive oil (as a filler) to the resulting composition and a mixture of nipazole and nipagin (0.03 % by weight of the contents), the composition was manually mixed and poured into subsequently gelatin coated capsules for tightness. The quality indicators of the obtained capsules were studied in accordance with the requirements of the State pharmacopoeia XIV of Russian Federation (description, disintegration, dissolution, uniformity of dosage, residual organic solvents), as well as oxidation indicators.Results and discussion. During the research it was found that the obtained samples of capsules containing resveratrol 40 mg/caps. as an active substance, and tween 80 as a solubilizer, had a good disintegration. The substance is well soluble in hydrochloric acid condition, which indicates its high bioavailability.Conclusion. To produce capsules with resveratrol (40 mg/caps.) containing tween 80, glycerin, citric and ascorbic acids, excipients were selected according to studies that confirm the improvement of resveratrol bioavailability. The quality of the dosage form was assessed in accordance with the State Pharmacopoeia XIVth edition: it was shown that the use of Tween 80 as a solubilizer increases the release of resveratrol in the environment of gastric juice.

Novel pendrin inhibitor attenuates airway hyperresponsiveness and mucin expression in experimental murine asthma

Novel pendrin inhibitor attenuates airway hyperresponsiveness and mucin expression in experimental murine asthma

Особенности молекулярно-массовых характеристик сополимеров, синтезированных в присутствии системы триэтилбор – кислород, при варьировании времени введения бутилакрилата в кипящий винилбутиловый эфир

The copolymers of butyl acrylate with vinyl butyl ether were synthesized by dosing the active monomer in the presence of an oxidizing agent and triethylboron isolated from the complex with hexamethylenediamine in a solution of vinyl butyl ether by adding methacrylic acid in an amount proportional in moles to the amount of amine before introducing butyl acrylate. The triethylboron was oxidized by the air oxygen remaining in the reaction mixture during the boiling of vinyl butyl ether. The dosing of butyl acrylate was carried out at varying times: 20 minutes, 40 minutes and 60 minutes, and then the reaction mixture was thermostated for some time. At the end of the polymerization, the liquid fraction was distilled off. The obtained samples of copolymers, which were viscous, were dried; their conversion was evaluated by dry residue gravimetrically. Molecular weight parameters were determined for all samples by gel permeation chromatography. A differential refractometer R-403 (Å (Shimadzu) was used as a detector. Tetrahydrofuran was used as the eluent. Narrow-dispersed polystyrene standards were used for calibration. Polystyrene samples were converted to copolymer with the use of standard formulas for polystyrene samples. It has been shown immediately after finishing butyl acrylate dosing that copolymer molecular weight distribution curves are bimodal, oligomeric molecular weight distribution curves have low molecular mass (M n less than 1000) and polydispersity coefficient (M w /M n )=1.1-1.2. Significantly larger low molecular weight modes have a molecular weight value ~30000, in all cases. Similar proportions for these two peaks are observed after thermostating the reaction mixtures after the introduction of butyl acrylate at the boiling point of vinyl butyl ether for another 20 minutes, the oligomeric curve of the molecular weight distribution of the first sample shifts in relation to that for the copolymer sample, selected immediately after dosing butyl acrylate for 20 minutes, and increasing the values of its molecular weight while maintaining polydispersity coefficient of 1.1. At the same time, for the other two samples, no shift in the molecular weight distribution is observed, as well as changes in the molecular weight values. In addition, the proportion of oligomer in relation to the low molecular weight polymer with a molecular weight of ~ 30000 decreases. Longer temperature control of the reaction mixture for two hours and more, after the end of dosing of butyl acrylate for both 40 and 60 minutes, unlike the process with dosing butyl acrylate for 20 minutes, also does not shift the molecular mass distribution curves of both peaks. This decreases the proportion of oligomeric peak in both cases.

Electron-Beam Processing of Petroleum Sludge

Thermal radiolysis under the conditions of electron-beam distillation at a dose to 240 kGy converts petroleum sludge into C4–C31 hydrocarbons with a yield to 80 wt %. The condensate distilled off contains about 20 wt % alkenes, thereby indicating the chain regeneration and thermal fragmentation of bulky alkyl radicals. The yield of the condensate increases to 90 wt % in the case of mixing the initial petroleum sludge with lignin. In this case, the yield of alkenes is lower due to the binding of unsaturated compounds by the components of charcoal and tar and because of a change in the mechanism of alkane fragmentation in the presence of lignin.

Polymer Technology of Porous SiC Ceramics Using Milled SiO2 Fibers

The paper describes a developed polymer composition and a process for manufacturing highporous chemically pure silicon carbide ceramics from this composition, using milled industrial wastes of quartz fiber non-woven fabrics as the source of silicon dioxide, which is important as a rational utilization of these wastes. The necessity of pre-milling of the SiO2 fibers was experimentally substantiated. Without this stage, the duration of treatment at 1400°C under dynamic vacuum considerably (≥12 h) increased, because of the non-uniform distribution of the components in the polymer composite. In the case of stoichiometric ratio of SiO2 and carbon formed upon pyrolysis of the polymeric phenol binder, the obtained SiC ceramic contained a large amount of unreacted carbon. This indicaties that side reactions take place to give volatile silicon monoxide, which is distilled off from the reactor. The effects of the milling time of SiO2 fibers and the carbothermal reduction temperature on the elemental and phase composition, density, and porosity of the obtained samples and the ultimate compressive strength were studied. Analysis of the experimental results served for optimization of the composition of the initial polymer composites. As a result, highly porous (83%) and relatively strong (ultimate compressive strength of 8.2MPa) SiC-ceramic samples free from unreacted carbon and silicon dioxide and other stubborn impurities were fabricated at 1400°C (dynamic vacuum, heat treatment for 4 h).