Fine Chemical Technologies

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Vol 15, No 6 (2020)
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9-15 19

Objectives. The study aims to analyze the dichlorocarbenation of the isoamylene fraction, which is a mixture of 2-methyl-butene-1 and 2-methyl-butene-2, in order to obtain the corresponding alkyl-gem-dichlorocyclopropanes in quantitative yield, and also to determine their structure.

Methods. In order to determine the qualitative and quantitative composition of the reaction masses, the following analysis methods were used: gas-liquid chromatography (using the Crystal 2000 hardware complex), mass spectrometry (using a Chromatec-Crystal 5000M device with NIST 2012 database), and nuclear magnetic resonance (NMR) spectroscopy (using a Bruker AM-500 device at operating frequencies of 500 and 125 MHz).

Results. Alkyl-gem-dichlorocyclopropanes were synthesized from an isoamylene fraction in the presence of catamine AB as a catalyst. Alternatively, isomeric alkenyl-gem-dichlorocyclopropanes were obtained on the basis of isoprene, and by reduction, the corresponding alkyl-gemdichlorocyclopropanes were synthesized. The synthesized substances were analyzed by gasliquid chromatography, mass spectrometry, and NMR spectroscopy, as previously mentioned above.

Conclusions. The results show that the dichlorocyclopropanation of the isoamylene fraction proceeds quantitatively with the formation of a mixture of 2-methyl-2-ethyl-1,1dichlorocyclopropane and 2,3,3-trimethyl-1,1-dichlorocyclopropane. Using isoprene, countersynthesis through successive dichlorocarbenation and hydrogenation was used to synthesize 2-methyl-2-ethyl-1,1-dichlorocyclopropane, one of the products of dichlorocarbenation of the isoamylene fraction.


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Objectives. This study aims to obtain the amino acid derivatives of chlorophyll a and bacteriochlorophyll a for the targeted delivery of pigments to tumor foci. This will increase biocompatibility and, as a result, reduce toxic side effects. In addition to photodynamic efficiency, an additional cytotoxic effect is expected for the obtained conjugates of photosensitizers (PSs) with amino acids. This is owing to the participation of the latter in intracellular biochemical processes, including interaction with the components of the glutathione antioxidant system, leading to the vulnerability of tumor cells to oxidative stress.

Methods. In this work, we have implemented the optimization of the structure of a highly efficient infrared PS based on O-propyloxim-N-propoxybacteriopurpurinimide (DPBP), absorbing at 800 nm and showing photodynamic efficacy for the treatment of deep-seated and pigmented tumors, by introducing L-lysine, L-arginine, methionine sulfoximine (MSO), and buthionine sulfoximine (BSO) methyl esters. The structure of the obtained compounds was proved by mass spectrometry and nuclear magnetic resonance spectroscopy, and the photoinduced cytotoxicity was studied in vitro on the HeLa cell line.

Results. Conjugates of DPBP with amino acids and their derivatives, such as lysine, arginine, MSO, and BSO have been prepared. The chelating ability of DPBP conjugate with lysine was shown, and its Sn(IV) complex was obtained.

Conclusions. Biological testing of DPBP with MSO and BSO showed a 5–6-fold increase in photoinduced cytotoxicity compared to the parent DPBP PS. Additionally, a high internalization of pigments by tumor cells was found, and the dark cytotoxicity (in the absence of irradiation) of DPBP-MSO and DPBP-BSO increased fourfold compared to the initial DPBP compound. This can be explained by the participation of methionine derivatives in the biochemical processes of the tumor cell.

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Objectives. The purpose of this study was to develop an objective instrumental method for assessing microbial contamination and expressing the probiotic and antibiotic properties of food, pharmacological, and other products.

Methods. The developed method consists of periodic (every 2 h) registration of changes in pH, redox potential, and electrical conductivity of a liquid nutrient medium incubated in the presence and absence of viable test microorganisms and test samples.

Results. Using liquefied CO2 from 10 different types of plant materials, we carried out a comparative analysis of probiotic and antibiotic activities against Lactobacillus acidophilus of various concentrations of subcritical whole extracts obtained.

Conclusions. Among the studied plant extracts, the most active prolonged antibiotic properties were exhibited by extracts from the leaves of Eucalyptus globulus Labill. and seeds of Illicium verum Hook.f. at a concentration in the test medium (CTE) more than 3 vol %, whereas the most active prolonged probiotic properties were exhibited by an extract from the herb of Mentha arvensis L. at CTE = 0.2 vol %. In most cases, the initial antibiotic activity of the tested extracts (TEs) was greater than their prolonged activity. Also, the mid-term (in terms of TEs interaction time with test microorganisms) antibiotic activity of TEs was intermediate in value between their initial and prolonged activity. In the test medium, the decreasing concentration of TEs decreases their antibiotic activity monotonically and increases their probiotic activity, suggesting that the biological activity of products, including various plant extracts, is largely determined not only by the raw material and the method of extracting biologically active substances from it but also by the concentration of the extract in the product and by the interaction time of the said product with microbiota and others. In most cases, a significant number of tests could establish the exact nature of these dependencies. The proposed method is much more rapid, objective, and informative and less laborious and material-intensive than using standard microbiological methods in assessing the initial microbial contamination and the probiotic and antibiotic properties of various samples of both the new and already approved pharmaceuticals, foods, and other products, as well as the individual ingredients and additives.


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Objectives. This work aimed to develop technology to produce biodegradable hybrid composite (BHC) films based on low-density polyethylene (LDPE) 115030-070 and thermoplastic starches (TPS) of various origins (corn, pea, and rice), with distilled monoglycerides as the plasticizer. The properties of the produced BHC films were studied and the optimal native starch : glycerol : monoglycerides ratio is proposed.

Methods. TPS and BHC films based on this material were produced from different types of native starches in laboratory extruders (Brabender and MashPlast, Russia), and the extruded melts were subjected to ultrasonic vibrations. The structure and appearance of the BHC films were studied using scanning electron microscopy and rheology. Their biodegradability was assessed by immersing them in biocompost for three months. To evaluate the mechanical performance of the BHC films produced with and without ultrasound, the changes in tensile stress and elongation at break were determined during the biodegradation process.

Results. The BHC films had a homogeneous structure, except small agglomerates (non-melted starch grains), which did not reduce their quality. The films with monoglycerides had high tensile strength, which was comparable with low-density polyethylene. After removing samples of the BHC films from the biocompost, their tensile strength decreased by 20%, which shows their biodegradability.

Conclusions. The produced biodegradable composite films and the technology used to produce them will be applicable for the packaging industry to reduce environmental impact.

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Objectives. The main indicator that determines electrical conductivity of rubbers is specific volumetric electrical resistance (ρv ). The purpose of this work is to investigate changes in this indicator during swelling and deswelling of electrically conductive rubbers. When considering the swelling process of rubbers in liquid media at a molecular level, an analogy of this process with mechanical deformation of the material is drawn and common features and differences of these processes are revealed.

Methods. For rubber compositions based on paraffinate and alkyl sulfonate nitrile butadiene rubbers, the degree of their swelling and the change in linear dimensions in heptane and in gasoline grades 80, 92, and 95 were determined. The ρ v value was determined by a potentiometric method: the initial value was measured after temperature control of rubbers for 1 h at 120°C, and the second measurement was carried out after these rubbers were swollen in the solvents for 48 h, followed by drying at 20°C to a constant weight and repeated temperature control under the same conditions. Using an IR Fourier spectrometer, spectra of the solvents used were obtained before and after identification of the investigated rubber samples in them.

Results. It was shown that the type of rubber and solvent used influence the degree of rubber swelling. Rubber compositions based on natural rubbers with a large amount of attached acrylonitrile, obtained in the presence of an alkyl sulfonate emulsifier, have the highest resistance to swelling. The effect of the used solvent on the change in the degree of swelling is determined by its affinity for rubber and the presence of polar additives that increase the octane number of gasoline. It was established that the linear change of the samples upon swelling in the indicated solvents varies according to the length and thickness of the samples. Results show that depending on the type of rubber used and the degree of its filling, the described rubber processing technology leads to a decrease in the ρ v value by 2 to 20 times. The greatest effect of ρ v reduction is observed in low-filled rubber compositions based on paraffinate nitrile rubbers. The spectra of the frustrated total internal reflection of the solvents after their interaction with the studied rubbers show that particulate extraction of dibutyl phthalate, which was used as a plasticizer in rubber compounding, takes place as a result of rubber swelling.

Conclusions. The proposed method of rubber processing reduces the ρ v value by removing dibutyl phthalate from the studied rubbers and forming a more developed carbon–elastomer structure. Furthermore, it solves the problem of the negative effect of the plasticizer on the ρ v value of rubber without excluding it from the rubber composition.


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Objectives. To develop physical and chemical bases and methods to obtain rhenium–ruthenium isoproxide Re4-yRuyO6(OPri)10 —a precursor for obtaining a high-temperature alloy—from ruthenium acetylacetonate and rhenium isoproxide acquired by electrochemical methods.

Methods. IR spectroscopy (EQUINOX 55 Bruker, Germany), X-ray phase and elemental analyses, energy-dispersive microanalysis (EDMA, SEM JSM5910-LV, analytical system AZTEC), powder X-ray diffraction (diffractometer D8 Advance Bruker, Germany), experimental station XSA beamline at the Kurchatov Synchrotron Radiation Source.

Results. The isoproxide complex of rhenium–ruthenium Re4-yRuyO6(OPri)10 was obtained, and its composition and structure were established. Previously conducted quantum chemical calculations on the possibility of replacing rhenium atoms with ruthenium atoms in the isopropylate complex were experimentally proven, and the influence of the electroconductive additive on the composition of the obtained alloy was revealed.

Conclusions. Physical and chemical bases and methods for obtaining rhenium–ruthenium isoproxide Re4-yRuyO6(OPri)10 were developed. The possibility of using rhenium–ruthenium Re4-yRuyO6(OPri)10 as a precursor in the production of ultra- and nanodisperse rhenium–ruthenium alloy powders at a record low temperature of 650°C were shown.


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Objectives. The technological process for the production of sheet glass by the float method is continuous and large-scale. Most European cars (up to 90%) are factory-tinted green; the bulk of the glass is painted in the desired color during the production process. The introduction of modern information technologies and digitalization has opened up opportunities for a significant increase in the efficiency of glass production. Accounting for the amount of drawn and cut glass allows you to evaluate an important indicator of the production work—the glass utilization rate, which determines the percentage of quality glass in the total output. The yield of the quality glass depends on the technological waste in the production process. To assess the effect of waste arising at the production stages on the glass utilization rate, an analysis of the statistical data of the float line operation was carried out. These statistical data differ from the normal law of probability distribution, which limits the use of traditional statistical control methods. Regression models do not always give an accurate mathematical description of the process since the variance of the conditional mathematical expectation of the output variable relative to the input is not a consistent characteristic of the relationship between the input and output variables. The purpose of this work is to study the application of information modeling theory for the analysis and control of the technological process of green glass production in terms of its utilization rate.
Methods. The technique of modeling technological chains has some peculiarities with that for operations modeling. It analyzes operations to identify possible information links between parameters. Thus, the process of obtaining the utilization rate of green glass in the production process can be followed. This study analyzes the influence of the paired and triple interactions of waste on the process of affording the utilization rate of glass at the stages of green glass production.
Results. Information modeling of the technological process of affording the utilization rate of green glass in the production process has been carried out. Informational analysis results in a conclusion about the sufficiency of the control of the utilization rate of green glass in the production process according to informatively related parameters—waste at the stages of glass melting, annealing, and flanging.
Conclusions. The selected method of information control of the glass utilization rate can be used in quality management systems in the production of green glass by the float method.

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Objectives. This article aims to describe, elaborate, and test a general algorithmic method for constructing the structure–property models for organic compounds.
Results. The construction of the models is based on the statistical analysis of some sets of chemical structures of definite classes with known property values. These models have some forms of correlation equations. For the representation of chemical structures in this method, the special weighted molecular graphs (MGs) that reflect some peculiarities of the spatial structures of the corresponding molecules are used. The proposed method is realized in two steps. First, it is assumed that the required structure–property equation has a definite form and depends on several adjusted numerical parameters and two changeable functions of one variable. In this step, from some set of functions, the pair of functions that provide the best model is selected. In the second step, the best model (from the previous step) is modified. For this purpose, the classification of the vertices of MG by the chemical symbols of the corresponding atoms and their first-order environments is fulfilled. Further, the graph edges are classified according to the classes of the vertices which they connect. Furthermore, the numerical correction terms for the initial weights of the vertices and edges are introduced, and they improve the obtained model. The final result of the model-construction process is the equation of the definite form containing concrete numerical values of its parameters. Some examples of the application of the elaborated method for constructing the structure–property models for the concrete properties and classes of compounds are presented. The following classes of organic compounds and their physicochemical properties are considered: 1) the boiling point of alcohols, 2) the water solubility of alcohols, 3) the boiling point of sulfides, and 4) the retention indices of alkylphenols. The obtained results indicate the efficiency of the proposed approach and the significance of introducing the second step to the method.
Conclusions. In this work, a general algorithmic and computerized method for constructing the structure–property models of organic compounds is suggested. Examples of the application of this method demonstrated its high efficiency. The method is suitable for any class of organic compounds and properties, which are quantitatively measured. Owing to its high efficiency, the structure–property models obtained by this approach can be employed to calculate the properties of chemical compounds for which experimental data are unavailable. 

ISSN 2410-6593 (Print)
ISSN 2686-7575 (Online)