Naphthalene-based bis-N-salicylidene aniline dyes: Crystal structures, Hirshfeld surface analysis, computational study and molecular docking with the SARS-CoV-2 proteins

In this work, we report structural and computational studies of a series of naphthalene-based bis-N-salicylidene aniline dyes, namely N,N′-bis-salicylidene-1,5-diaminonaphthalene (1), N,N′-bis(3-hydroxysalicylidene)-1,5-diaminonaphthalene (2) and N,N′-bis(3-methoxysalicylidene)-1,5-diaminonaphthalene (3). For 3, two polymorphs are known, namely 3red and 3yellow. Both polymorphs of 3 were analyzed and discussed. All the molecules adopt an enol-imine tautomer, stabilized by two intramolecular O–H⋯ N hydrogen bonds. The structure of 2 is further stabilized by a couple of additional O–H⋯ O hydrogen bonds and by intermolecular O–H⋯ O interactions, yielding a 1D zig-zag supramolecular chain. Molecules of 2, 3red and 3yellow are interlinked through intermolecular C–H⋯ π interactions, while the crystal packing of 1 and 2 is also described by intermolecular π⋯ π interactions. More than 90% of the total Hirshfeld surface area for all the discussed molecules is occupied by H⋯ H, H⋯ C, H⋯ O and C⋯ C contacts. The polymorphs 3red and 3yellow, despite being chemically the same, differ geometrically, thus yielding remarkably different Hirshfeld surfaces. The Hirshfeld surface of 3yellow is very similar to that of 2. All structures are mainly characterized by the dispersion energy framework followed by the less significant electrostatic energy framework contribution. Molecular docking studies were employed to inspect the effect of 1–3 on the SARS-CoV-2 protein targets. The docking analysis revealed that the dye 2 showed the best binding energies toward Papain-like protease (PLpro, –10.40 kcal/mol), nonstructural protein 14 (nsp14 (N7-MTase), –10.10 kcal/mol), RdRp-RTP (–9.70 kcal/mol) and nonstructural protein 3 (nsp3_range 207-379-MES, –9.30 kcal/mol). The obtained results can give an insight into chemical and biological activities of the studied molecules that could aid in designing of potent reagents SARS-CoV-2. © 2021, Iranian Chemical Society.Ministry of Education and Science of the Russian Federation, Minobrnauka: 730000Ф.99.1, БВ09АА00006The authors thank Esin Akı Yalcin and the research group for technical assistance. This work was supported by state assignment of the Ministry of Science and Higher Education of the Russian Federation (Project Reg. No. 730000Ф.99.1.БВ09АА00006. This work was supported by state assignment of the Ministry of Science and Higher Education of the Russian Federation (Project Reg. No. 730000Ф.99.1.БВ09АА00006)

Computational Analysis of Molnupiravir

In this work, we report in-depth computational studies of three plausible tautomeric forms, generated through the migration of two acidic protons of the N4-hydroxylcytosine fragment, of molnupiravir, which is emerging as an efficient drug to treat COVID-19. The DFT calculations were performed to verify the structure of these tautomers, as well as their electronic and optical properties. Molecular docking was applied to examine the influence of the structures of tautomers on a series of the SARS-CoV-2 proteins. These tautomers exhibited the best affinity behavior (−9.90, −7.90, and −9.30 kcal/mol, respectively) towards RdRp-RTR and Nonstructural protein 3 (nsp3_range 207–379-MES). © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Funding: This work was supported by state assignment of the Ministry of Science and Higher Education of the Russian Federation (Project Reg. No. 720000Φ.99.1.БЗ85AA13000)

In silico analyses of betulin: DFT studies, corrosion inhibition properties, ADMET prediction, and molecular docking with a series of SARS-CoV-2 and monkeypox proteins

We report detailed computational studies of betulin — a pentacyclic naturally occuring triterpene, which is a precursor for a broad family of biologically active derivatives. The structure, electronic, and optical properties of betulin were studied by the density functional theory (DFT) calculations in gas phase. The reactivity and the reactive centers of betulin were revealed through its global reactivity descriptors and molecular electrostatic potential (MEP). The DFT calculations were also applied to probe betulin as a potential corrosion inhibitor for some important metals used in implants. Electron charge transfer from the molecule of betulin to the surface of all the examined metals (Ti, Fe, Zr, Co, Cu, Cr, Ni, Mn, Mo, Zn, Al, W, Ag, Au) was revealed, of which the best results were obtained for Ni, Au and Co. Bioavailability, druggability as well as absorption, distribution, metabolism, excretion and toxicity (ADMET) properties of betulin were evaluated using the SwissADME, BOILED-Egg and ProTox-II tools. Molecular docking was applied to examine the influence of the title compound on a series of the SARS-CoV-2 proteins as well as one of the monkeypox proteins. It was established that betulin is active against all the applied proteins with the best binding affinity with papain-like protease (PLpro) and spike protein (native) of SARS-CoV-2. The title compound is also active against the studied monkeypox protein. Interaction of betulin with papain-like protease (PLpro) was studied using molecular dynamics simulations. © 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.Ministry of Education and Science of the Russian Federation, Minobrnauka: 720000Ф.99.1, БЗ85AA13000This work was supported by state assignment of the Ministry of Science and Higher Education of the Russian Federation (Project Reg. No. 720000Ф.99.1.БЗ85AA13000)

Ecological and genetic assessment of the consequences of radiation influence on contaminated areas

The objects of study are the territory of the districts of the West Kazakhstan region of the Republic of Kazakhstan adjacent to the Kapustin Yar test site: Bokeyordinsky, Zhangalinsky, Zhanibeksky, Kaztalovsky, Akzhayiksky and Syrymsky. The purpose of the work is to conduct a radioecological survey of contaminated areas and to study the content of pollutants in environmental objects, biota (rodents, fish and biosubstrates of domestic animals) by physicochemical methods to assess the risk of the landfill’s impact on biota and humans. This paper presents the results of expeditionary and laboratory research on the pollution of environmental objects in the areas adjacent to the landfill. Indicators of the gamma-survey of the levels of radiation background of the surveyed territories as wellas data on pollution of soil, surface and ground waters, dominant forms of plants, biosubstrates (hair of domestic animals: camel, horse, cow) are given. The generally accepted research methods were used: standard sampling me thods, radiological, atomic adsorption spectrophotometry, cytogenetic (micronucleus) method. A reconnaissance and radioecological examination of environmental objects was carried out using analytical methods, which made it possible to determine the quantitative content of toxic components, the content of priority pollutants and radioactive isotopes. It has been established that the values of the volumetric activity of natural and man-made radionuclides in soil samples, drinking water and biosubstrates (pet hair, human peripheral blood samples) from settlements correspond to the value of the control level for this region. The measurements of radiation activity by gamma radiation showed that along the perimeter of the surveyed territory of the test site and in nearby settlements the radiation level is in the range of 0.06–0.014 μSv/h. A slight excess of the level of radioactivity persists in the area near the fall of missiles in the Bokeyordin region. The investigated regions are characterized by an insignificant level of background radiation, the average DER value for the regions as a whole is 0.14 μSv/h. The absolute maximum, 0.73 μSv/h, was recorded at the points of missile impact in the Kaztal region

Endophytic Bacillus bacteria with RNase activity in the resistance of potato plants to viruses

Viral diseases annually cause significant crop losses and significantly reduce the quality of products, including potatoes, some of the most important crops. Currently, viruses cannot be controlled with chemical pesticides, since known antiviral compounds are teratogenic and hazardous to people’s health. Biocontrol agents based on endophytic microorganisms may be an alternative to them. Many strains of Bacillus produce ribonucleases (RNases). Our laboratory possesses a collection of bacteria that produce various metabolites and have RNase activity. The results showed that the inoculation of potato with B. subtilis 26D and B. thuringiensis increased the grain yield by 32–43 %. In addition, the treatment of potato plants with Bacillus spp. significantly reduced the infection of potato plants with virus M. The prevalence of the disease in potato plants was significantly reduced from 60 % in the control to 18 % (B. subtillis 26D) and 25–33 % (B. thuringiensis) in the inoculated plants. Similarly, the infection index decreased from 14 in the control to 1 in the inoculated plants. The further study of molecular mechanisms related to bacterial induction of plant defense reactions in response to viral infections will lead to a better understanding of stress resistance problems. The endophytic microorganisms studied in this report may become the basis for the creation of biological agents for plant protection

EVALUATION OF PLAGUE EPIZOOTIC CONDITION OF PREARAL-QARAQYM PLAGUE FOCUS OF KAZAKHSTAN IN SPRING AND SUMMER TIME OF 2013

In the Republic of Kazakhstan, there a re the natural plague foci. For the analysis, the passport data of plague epizooty activity in the PreAral-Qaraqym plague focus of Qyzylorda Province were collected. The data were received in the spring and summer seasons of2013. For the research of plague epizooty, the places ofstucfy were determined. The selection of places was based on the parameters as a presence of settlements, annual data of plague epizooty activity in the focus. Then the places were studied by serological and bacteriological methods; and the plague epizooty was found in some of them. During spring and summer seasons the plague strains were isolatedfrom the plague hostRhombomys opimus and plague vectors X. skrjabini, H. asiaticum, N. laeviceps, Cit. tesguorum, E. oshanini. For spatial and temporal analysis, the received positive data were processed by ArcGIS 10 program. The tasks of the analysis were definition of the plague epizooty center for plague risk zoning of the area; definition of direction of the plague epizooty for calculation of possibility of the plague epizooty increasing; calculation of plague epizooty radius for conducting of plague prophylaxis measures; definition of zones where the possibility to be infected with plague is high for population. The plague epizooty model of PreAral-Qaraqym plague focus was created, in the framework of plague epidemiological surveillance system, application the modeling in program ArcGIS 10 is useful instrument for detection of plague risk areas, and conduction of plague prophylaxis measures for protection of local population form the plague

Morphological structure, agrophysical and agrochemical properties of irrigated typical gray and grass soils

The article presents information on morphological structures, general physical and agrochemical properties of typical irrigated gray and grassland soils. The general physical properties of the soil are that in typical gray soils the bulk density decreases and the porosity increases, while in grassland soils the bulk density decreases and the total porosity increases compared to typical gray soils. A typical irrigated gray soil is composed of large dust particles according to its mechanical composition and belongs to the category of medium sandy loam. According to the level of availability of humus and nutrients of the studied soils, typical gray and meadow soils irrigated are low in humus (0.36-0.87%), very low in mobile phosphorus (5.33-15.60 mg/kg), exchangeable potassium It is highlighted that it is provided with low (100-200 mg/kg)

Psychological Fundamentals of Child Raising in the Family

This article discusses the fact that the main part of child rearing is up to 5 years, the psychological features of family upbringin