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Blood oxygen transport regulation by physical activity increase within training dynamics is provided with different mechanisms: from the quantitative and qualitative erythron restructure (including endogenous erythropoietin rise and main erythrocyte index shifts) to change in haemoglobin affinity to oxygen, its heterogeneous structure and blood flow growth as a result of endothelium hyperpolarisation. However, the erythrocyte itself remains a key performer in blood velocity control, due to its structure and functions. This review summarizes the data of modern scientific literature on the characteristics of erythrocytes, which make these cells one of the key links in the oxygen transport system of the blood. The focus on this property of erythrocytes during physical activity is based on the fact that the athlete’s muscles must be supplied with enough oxygen to ensure high performance. Specific training and extra-training factors affecting the content of erythrocytes have been determined. The membrane structure is treated as a significant erythrocyte part in determining its deformation and microvascular blood transport. Enzymes associated with the erythrocyte membrane and affecting cell viability and performance are described. Besides, it is stressed on monitoring erythrocyte indices via modern equipment and assessing lipid peroxidation, which leads to disorders in erythrocyte membrane structure and functions.

This work is dedicated to the study of structural, morphological, and optical properties of stable isoindole derivative, which keeps o-quinoid structure. Corresponding properties were studied using...

Today, a search in the experiment and practice of sports training of pharmacological agents, which at various levels of organization of the living organism, including both muscle tissue and muscle cells, were able to mitigate the negative consequences ofsuper-intense long-term physical loads, does not have to stop. One such universal means is succinic acid, which is a natural metabolite of the Krebs cycle, and, therefore, directly related to the mechanisms of energy generation in the body. Since this process in cells, and muscle tissue cells is no exception, it takes place in mitochondria. The definition of the structural-functional rearrangements of the mitochondrium of myocytes during physical loads is very interesting especially when succinic acid is used as an organoprotector. Material and methods. Physical load was simulated for three weeks in rats by swimming with an additional load. 10 intact animals served as control, and the remaining 20 were equally divided into two study groups, the first was with physical load and the second group had the same load application of succinic acid in a daily dosage of 2.5 mg per animal weighing 220-250 g, based on the corresponding extrapolation of dosages to an adult human. Research on experimental animals was carried out in compliance with all norms of bioethics. Electron microscopic studies were carried out on the material of the tissue gastrocnemius’ muscle. Results and discussion. The results of the studies showed that hypoxia of the subcompensated load was found in the cells of this tissue, as well as activation of mitochondrial morphogenesis by 58.3% and 69.0% in both the subsarcoleal and the intraamyofibrillic subpopulations, respectively. In the experiment we established an increase in the number of membrane structures and an increase in the average diameter of mitochondria, leading to an increase in the energy capacity of the mitochondrium. These phenomena can be attributed to compensatory-adaptive changes under the influence of physical load. The application of succinic acid activates these processes to an even greater extent, i.e. the application of this pharmacological agent has a powerful protective effect on the optimization of energy metabolism of muscle tissue under physical loads. Thus, it showed that succinic acid contributed to the reduction of the structural signs of endothelial and mitochondrial dysfunction, contributing, in accordance to its known properties, optimization of energy metabolism and preservation of the integrity of mitochondria with levelling of the structural manifestations of mitochondrial dysfunction. This, in turn, leads to the optimization of macroergs products and hence increases in physical performance. Conclusion. The stated facts at a new level of development of science prove the expediency and effectiveness of using succinic acid and pharmacological agents based on it in order to improve the functional state of the body of athletes and their motor qualities

In this work, we have studied the dibenzofluorene derivative belonging to the KuQuinones family. We have investigated the structural, morphological and optical properties of this derivative, which is part of the new sub-class of dibenzofluorenes, due to its existence as a zwitterion, in contrast to other KuQuinones. The optimization of the dibenzofluorene derivative was performed using density functional theory (DFT) by the M06-2X/cc-pVTZ + PCM (CH3CN) method. The UV spectra were calculated using CAM-B3LYP/cc-pVTZ and W97X/cc-pVTZ + PCM (CH3CN) methods. Our theoretical results confirm and explain the obtained experimental data.

The influence of the main parameters on the process of obtaining artificial carnallite and its quality has been established. It is shown that to obtain a product with a high content of the carnallite phase and a low content of bischofite and KCl, it is necessary to use magnesium chloride solution with the concentration of 27-30 % and preheated ground potassium chloride. The process should be carried out at the temperature of 80 °C. The formation of synthetic carnallite, close in composition to the enriched one, occurs when the ratio of potassium chloride to magnesium chloride in the initial mixture is equal or close to their stoichiometric ratio in carnallite. With an excess of potassium chloride in the reaction mixture, an increased content of potassium and sodium chlorides in the product is observed, and with its deficiency, the product contains an increased amount of bischofite phase. To reduce the hydrolysis of magnesium chloride during dehydration, a slight excess of potassium chloride should be maintained in the mixture entering the synthesis. It is shown that the most advantageous scheme for producing artificial carnallite provides for incomplete evaporation of desulfurized liquor in the presence of potassium chloride with the return of circulating carnallite liquor to the desulfurization stage.

A study has been carried out on the effect of the domestic pharmacological armadin long preparation (2-ethyl-6-methyl-3-hydroxypyridine succinate) on the physical working capacity of athletes under the maximum in-tensity force loads characteristic of modern sports. Since pharmacology in sports is constantly searching for non-toxic drugs of the metabolithotropic origin that would have the ability to promote physical efficiency and slow down fatigue without toxic effects on the body, we have chosen for our research a drug based on succinic acid, which is a natural metabolite of the Krebs cycle. It has been shown that the armadin long preparation, when applied on a course for three weeks, positively affects the parameters of special working capacity associated with the improvement of the oxygen-transport function of blood. The metabolic basis of this phenomenon is the inhibition of a decrease in the pH of the internal environment of the body with the subsequent development of lactate-acidosis and the ability of the armadin long drug to accelerate the processes of angiogenesis, and, accordingly, the transport of oxygen to the athlete’s working muscles. The intensity of the formation of new growth factor (VEGF). Such data substantiate the expediency of the use of succinic acid-based agents to prevent negative metabolic changes and to slow down the onset of fatigue in athletes under intense physical loads

The synthesis of a new tetratopic extended-TTF (exTTF; 9,10-di(1,3-dithiol-2-ylidene)-9,10-dihydroanthracene) ligand, bearing four pyridyl coordinating functions on the dihydroanthracenyl platform rather than on the 1,3-dithiol rings (previously described regioisomer), was reported. The self-assembly behaviors of both electroactive regioisomers were compared. While a M4L2 container was obtained with the previous one when reacted with the square planar Pd(dppf)OTf2 complex, the new ligand, when reacted under the same conditions, affords a M6L3 hexagonal structure that is composed of nine electro-active subunits that can be reversibly oxidized.

Formyl MIDA boronate has been known to be an elusive type of acylboronate that has not been obtained to date. In this work, an approach to the one-pot preparation and chemical transformations of formyl MIDA boronate were developed to provide new types of α-functionalized organoboron compounds. Among them are acylboronate reagents which present boron-substituted analogues of ynones and β-dicarbonyl compounds. The developed synthetic procedures, utilizing formyl MIDA boronate, are tolerant to diverse functional groups, making this reagent an advantageous C1 building block for extending the scope of organoboron chemistry.

Thin films from the LaVO4:Eu, Ca nanoparticles were successfully grown by pulsed laser deposition method on glass and silicon substrates for the first time. Morphology and thickness of the films depend on the type of substrate and number of pulses. The films are of 27–220 nm thickness and formed by very small particles (up to 20 nm) and also can contain single nanoparticles with dimensions of 40–60 nm and sometimes agglomerates of nanoparticles. Spectral properties of the samples have been investigated and discussed. The vanadate films deposited on the silicon substrates lead to appearance of antireflection properties in the visible range. Luminescence spectra of the investigated films consist of narrow lines caused by f–f transitions in the Eu3+ ions. For the samples on glass substrates the wide bands of glass emission also contributed to the spectra. The optimal experimental conditions which allowed to obtain films with promising applications as luminescent converters are considered.

Long-term physical activity causes restructuring in the various functions and systems of the body, which are, as a rule, adaptive in nature and occur at all levels of the structural organization of the body. The question of changes in the functional state of the cardiovascular system and, especially, the microcirculatory section of the circulatory system in normal and under the physical exertion and their relationship with ultrastructural remodelling in tissues, cells and cellular organelles is still remaining unclear. The aim of the study was to assess structural changes in the tissues of the calf muscle and myocardium that cause the development of adaptive mechanisms in response to prolonged physical exertion. We studied the structural components of tissue samples of calf muscle and the apex of the heart taken from mature Wistar male rats weighing 220-250 g in mass exposed to prolonged physical exertion by using electron microscopy. It has been shown that a long and intense physical loading causes the development of a number of compensatory-adaptive reactions directed at improving microcirculation processes, oxygen supply of skeletal muscles and myocardium, as well as maintaining an adequate level of metabolic processes. A detailed assessment of the functional state of the tissues studied is necessary for the early detection of signs of maladjustment under the constant loading in sports and the prevention of pathological states.

The results are presented of a study on spectral characteristics, electron microscopy data and antibacterial properties of Lactobacillus plantarum cell matrices filled with biologically synthesized in the presence of surfactants (S) silver nanoparticles (bioAgNP). The dependences of spectral characteristic of cell suspension of lactic acid bacteria L.plantarum with synthesized bioAgNP on S concentration were analyzed, namely: cationic two quaternary ammonium salt (CS) aethonium and anionic sodium decyl phosphate (AS). To control the process of bioAgNP production in microorganism cells, the method of spectroscopy in ultraviolet and visible regions was used. The antibacterial properties of modified L. plantarum cells dependent on synthesis condition and their composition were testified by disco diffusion method. The results are presented of electron-microscopy investigation of treated with concentrated sulfuric acid bionanocomposite material. It is shown that addition at the synthesis of an ionogenic S to the precursor solution affects structural and size descriptions of biogenic silver formed in L. plantarum cells. Since a concentration more then the critical concentration of micelle formation, aethonium presence resulted in forming of two NPs fractions, namely: stabilized in a cell wall subcolloidal particles having absorption band at 380 nm and also aggregated particles having spectral shoulder at 440 nm. S addition promoted the red shift of absorption spectra dependent on CS concentration and medium pH, however not dependent on AS concentration. It is shown that antibacterial properties of modified with S nanobiocomposite materials mainly depend on the NPs content in lactic acid matrices and on their size. Joint application of bionanocomposite and aethonium preparation close to the critical micelle concentration allowed to rise their activity in relation to Gram(+)bacteria and, at the same time, to bring down on an order (from 1.0 to 0.1 %) the ordinary therapeutic dose of aethonium.

A convenient methodology for constructing 6,6-difluorospiro[3.3]heptane scaffold – a conformationally restricted isostere of gem-difluorocycloalkanes – is developed. Alarge array of novel 2-mono- and 2,2-bifunctionalized difluorospiro[3.3]heptane building blocks was obtained through the convergent synthesis strategy using a common synthetic precursor – 1,1-bis(bromomethyl)-3,3-difluorocyclobutane. The target compounds and intermediates were prepared by short reaction sequences (6–10 steps) on multigram scale (up to 0.47 kg).

The effect of neodymium addition in the composition of complex bismuth cuprates Bi2Sr2–xNdxCaCu2Oy (0 ≤ x ≤ 0.1) on their structural and electrophysical characteristics and catalytic properties is found. It is established that increase in the neodymium content is accompanied by antibate (inverse) change in the unit cell parameters, increased structural defectiveness, and slight increase of the superconducting temperature. The increased activity of the Nd-substituted cuprates in the oxidation of CO is due to increase in the defectiveness of the structure and the content of mobile oxygen in the crystal lattice.

The high level of nuclear radiation threats in the modern world determines the need to find new means of pharmacological protection of the health of military personnel and civilians from the effects of ionizing radiation. Of particular scientific interest in this aspect are natural polyphenols as a promising basis for the development of newdrugs, radiomodifiers.Justification of the prospects of creating radioprotective agents based on compositions of plantpolyphenolic substances (PPS) and polysaccharides.The experiments were performed on 130 laboratory white rats-male of Wistar line sexually mature weighting 180-240 g. Animals once received a total X-ray dose equivalent to 4.25 Gy. The effects ofquercetin and patulaten to the processes of reparative regeneration under conditions of X-ray irradiation andagainst the background of butadione suppression were investigated. Indicators in the study groups were compared using the Student's t-test for independent samples; the differences were considered statistically significantat p0.05.The various biological properties of quercetin, in particular, the ability to bind hydroxyl radicals, is thepotential for developing radioprotective agents based on it. At the first stage of the study, the effect of PPS andtheir compositions with polysaccharides on reparative regeneration was studied against the background of its suppression in intact and irradiated animals. With the oral administration of PPS and their compositions with pectin towhite rats, 30 minutes before the administration of butadion, an increase in the processes of reparative regeneration in the cells of the covering epitheliumof the esophagus was observed. At the same time, quercetin granulescaused the most expressive effect, which increased the statistically significant value of the mitotic index by 78.5 %in relation to the group of animals injected with butadion. At the second stage of the study, the effect of polyphenolic substances and their compositions with pectin on the processes of reparative regeneration in intact and irradiated white rats was studied on a model of linear skin wounds. The prophylactic administration of quercetin granules and the treatment of wounds with 20 % sterile quercetin gel significantly accelerated the healing process.Experimental data indicate that quercetin granules have the ability to stimulate the processes of reparative regeneration, quercetin showed the greatest efficiency with simultaneous use inside and topically.The research results indicate the promise of developing radioprotective drugs that can stimulatereparative regeneration processes based on compositions of plant polyphenolic substances and polysaccharides invarious qualitative and quantitative ratios.Vysokyĭ riven' radiatsiĭno-iadernykh zagroz v suchasnomu sviti vyznachaie neobkhidnist' poshuku diievykh zasobiv farmakologichnogo zakhystu zdorov’ia viĭs'kovosluzhbovtsiv i tsyvil'nogo naselennia vid diï ionizuiuchogo vyprominiuvannia. Osoblyvyĭ naukovyĭ interes v ts'omu aspekti predstavliaiut' pryrodni polifenoly iak perspektyvni spolukydlia rozrobky farmpreparativ radiozakhysnoï diï.Meta. Obґruntuvannia perspektyv stvorennia zasobiv radiozakhysnoï diï na osnovi kompozytsiĭ roslynnykh polifenol'nykh spoluk (PFS)i polisakharydiv.Material ta metody. Eksperymenty provedeno na 130 laboratornykh bilykh statevozrilykh shchurakh-samtsiakh liniïWistar masoiu 180–240 g. Tvaryny odnorazovo otrymaly zagal'ne rentgenivs'ke oprominennia v dozi, ekvivalentniĭ 4,25 Gr. Doslidzhuvaly vplyv kvertsetynu i patulatenu na reparatyvnu regeneratsiiu na modeli liniĭnykhran shkiry na foni oprominennia ta na foni prygnichennia Butadionom. Pokaznyky v grupakh doslidzhennia porivniuvaly za dopomogoiu t-kryteriiu St'iudenta dlia nezalezhnykh vybirok; vidminnosti vvazhaly statystychno znachushchymy pry0,05.Rezul'taty doslidzhennia. Riznomanitni biologichni vlastyvosti kvertsetynu, zokrema spromozhnist' zv’iazuvatygidroksyl'ni radykaly, ie potentsialom dlia rozrobky na ĭogo osnovi radiozakhysnykh zasobiv. Pry peroral'nomuvvedenni polifenol'nykh spoluk ta ïkh kompozytsiĭ z pektynom bilym shchuram za 30 khv do vvedennia butadionu sposterigaly posylennia protsesiv reparatyvnoï regeneratsiï v klitynakh pokryvnogo epiteliiu stravokhodu. Pry ts'omunaĭbil'sh vyrazhenu diiu chynyly kvertsetynu granuly, iaki zbil'shuvaly statystychno dostovirnu velychynu mitotychnogo indeksu na 78,5 % porivniano z grupoiu tvaryn, iakym vvodyly butadion (kontrol'). Na drugomu etapidoslidzhennia vyvchavsia vplyv polifenol'nykh spoluk (PFS) ta ïkh kompozytsiĭ z pektynom na protsesy reparatyvnoï regeneratsiï u intaktnykh i oprominenykh bilykh shchuriv na modeli liniĭnykh ran shkiry. Profilaktychne vvedenniakvertsetynu granul i obrobka ran 20 % steryl'nym gelem kvertsetynu znachno pryskoriuvalo protses zagoienniaran. Eksperymental'ni dani svidchat' pro zdatnist' kvertsetynu granul posyliuvaty protsesy reparatyvnoï regeneratsiï, osoblyvo pry odnochasnomu zastosuvanni peroral'no i mistsevo.Vysnovky. Rezul'taty doslidzhen' vkazuiut' na perspektyvnist' rozrobky radiozakhysnykh preparativ, zdatnykhstymuliuvaty protsesy reparatyvnoï regeneratsiï na osnovi kompozytsiĭ roslynnykh polifenol'nykh spoluk ipolisakharydiv u riznykh iakisnykh i kil'kisnykh spivvidnoshenniakh.

International audience; A M2L2 metalla-macrocycles contructed through coordination driven self-assembly from the Pd(dppf)OTf2 complex (dppf = 1,1′-Bis(diphenylphosphino)ferrocene) and an electron-rich 9-(1,3-dithiol-2-ylidene)fluorene bis-pyridyl ligand is depicted. This molecular tweezer exhibits a cavity able i) to promote dimerization upon oxidation and ii) to bind an electro-deficient substrate with a remarquable association constant. Those properties are compared with those of a previously described regioisomer.

Simple and efficient synthesis of 2-(1,2,4-oxadiazol-5-yl)-2,3-dihydro-4H-chromen-4-ones is elaborated. The method relies on CDI-mediated cyclocondensation of substituted 4-oxochromane-2-carboxylic acids and amidoximes. The protocol allows the preparation of 2-oxadiazolylchromanones decorated with two pharmacophores (2,3-dihydro-4H-chromen-4-one and 1,2,4-oxadiazole) that are in high demand in drug discovery.

Selective chemical reactions create new possibilities for controlled synthesis of compounds with pre-designed properties for further use in medical chemistry, material science and other fields. This is especially useful for such synthetic methodology as [4+2] cycloaddition. Current work is dedicated to study of reactions between N-chiral maleinimides with cyclic dienes based on the pyridoisoindol. Pyrido[2,1-a]isoindol turned out to be the most practical object to study the first example of asymmetric variant of the Diels-Alder reaction involving condensed isoindols. Previously, we established that this heterocyclic system, in contrast to other azino- and azoloisoindols, upon undergoing cycloaddition with non-chiral maleinimides gives only rearranged adducts of the first type. This type of compounds have also interesting stereochemistry: in solid state they have twisted double bond (twist angle 7-10°), while in solution they exist as a mixture of athropodiastereomeres due to the asymmetric Carbon atom and hindered rotation around С–С bond between exocyclic double bond and 2-(α-pyridil)phenyl fragment. Initial expectation was that chiral induction would influence the ratio of corresponding athropodiastereomeres. Calculations show that there are four possible athropodiastereomeres due to the chiral center and sterically hindered chiral axis. In case of non-chiral dienophiles, reaction results in two major diastereomeres (for our purposes marked as A and B) with 70:30 ration and two minor isomers (marked С and D respectively), the latter constituting less than 5% of the total amount. Major and minor isomers are in constant complex equilibrium, controlled via slow rotation of around corresponding С-С bond on one hand (which is the reason for athropodiastereomeres between major forms A and B, shown via NMR spectra at different temperatures), and on the other hand – fast equilibrium due to the 1,5-sigmatropic shift (cause for the minor forms C and D). Target reaction was studied under standard conditions for this rearrangement and under the kinetic control in the inert atmosphere at -80°С using TiCl4 as catalyzer. We therefore show that reaction pathway is similar to our previous examples and results in rearranged adducts of the first type. Ratio of athropodiastereomeres (both major and minor forms) is different from previous examples using non-chiral 2-substituted maleimides. Asymmetric induction spontaneously transfers from influencing the Diels-Alder reaction to influencing synchronic sigmatropic rearrangement, which is the final stage in the formation of the rearranged adduct of the first type in condensed isoindol systems.

Previously, we have characterized the capsaicin-insensitive low pH-sensitive (caps−lpH+) subtype of small-sized nociceptive dorsal root ganglion (DRG) neurons that express acid-sensing ion channels, T-type Ca2+ channels, and have isolectin B4-negative phenotype. These neurons demonstrated increased excitability in a model of long-term diabetes, contributing to chronic pain sensation. Here we studied changes in the excitability of the caps−lpH+ neurons and underlying changes in the functional expression and gating properties of ion channels under complete Freund's adjuvant (CFA)-induced peripheral inflammation. We have found that, under these pathological conditions, the functional expression of the acid-sensing ion channels (ASICs) and voltage-gated Na+ channels, was increased. In addition, T-type Ca2+ current was significantly increased in the neurons at the membrane potentials close to its resting value. Altogether, the observed changes in the channel functioning shifted a pH level evoking an action potential (AP) toward its physiological value and led to an increase of evoked and spontaneous excitability of the caps−lpH+ neurons that may contribute to hyperalgesia and chronic inflammatory pain.

Mechanical stirring of particles into a melt is used to obtain a composite material based on alloy Al – 3.5% Mg – 0.4% Mn – 0.15% Zr – 0.15% Sc reinforced with particles of B4C. The microstructure, the phase composition, the density, the adaptability to rolling, and the mechanical properties of the composite material are determined. The material has a high corrosion resistance and a yield strength exceeding 245 MPa, which is higher than the yield strength of the steels used today for making spent-fuel storage racks.

Optimized synthesis of 1-methyltetrazolo[5,1-a]isoindole-derived amides and thioamides was elaborated. Based on 13C NMR spectroscopy and X-Ray diffraction studies data, it was proposed that zwitterionic resonance structures contributed significantly to the structure of these compounds. Geometry optimization was performed in vacuo using m06-2x/cc-pvtz method taking into account polarizing effect of environment (PCM model) and specific intermolecular interactions. Electronic density distribution in these molecules was analyzed using NBO method. Using Δ(HOMOdiene–LUMOdienophile) for amides and thioamides in vacuo and in a protic solvent, possibility of Diels–Alder reaction was evaluated. Energies of π-π conjugation and n→σ* hyperconjugation for the amide derivative were estimated in vacuo, aprotic and protic solvents.

Results from experiments on the radial distribution of the magnetic fields in axial plasma flows formed during the compression of a plasma–current sheath carried out at the KPF-4-PHOENIX plasmafocus installation are presented. The plasma flows were generated in a discharge with stationary filling of the chamber with a working gas of argon or hydrogen, and also with a pulsed injection of argon. Analysis of the radial profiles of the magnetic field distribution and their time variations are used to localize regions of trappedmagnetic field, as well as regions where a return current flows at the periphery of the plasma flow. It is shown that the transverse (radial) size of the plasma flow depends on the density of the ambient medium (background gas) through which it propagates. These experiments were carried out in the framework of a project on laboratory simulations of non-relativistic jets from young stars.

This paper reports on the synthesis of new derivatives of ε-aminocaproic and γ-aminobutyric acid modified with a pyridin-2-yl substituent at the ω-position of the main chain. The hemostatic activity of both ε-aminocaproic acid itself and its various synthetic analogues is widely known. Likewise, numerous γ-aminobutyric acid derivatives are strong neurotransmitters extensively used in the treatment of the nervous system disorders. No less popular are biologically active substances containing a pyridine or piperidine fragment; among which there are antibiotics, antimalarial, anti-sclerotic and antiallergic drugs, as well as anti-depressants and analgesics. Therefore, the introduction of the pyridine fragment into the amino acid structures is interesting in terms of their potential biological activity investigation. So, a method for the synthesis of 5-amino-5-(pyridin-2-yl)pentanoic and 6-amino-6-(pyridin-2-yl)hexanoic acid has been developed by us. The proposed scheme is based on the available reagents using. The key stage is the Schmidt rearrangement of 2-(pyridin-2-yl)cyclopentanone and 2-(pyridin-2-yl)cyclohexanone, previously synthesized from pyridine N-oxide and cycloalkenyl morpholinide. For synthesized pyridine substituted cycloalkanones according to NMR spectroscopy, the presence of keto-enol tautomerism was established. As a result of Schmidt rearrangement, lactams (2-(pyridin-2-yl)piperidone and 2-(pyridin-2-yl)azepanone) are formed, and the last ones had been hydrolyzed in an acidic medium to open the lactam cycle. Thus, 5-amino-5-(pyridin-2-yl)pentanoic and 6-amino-6-(pyridin-2-yl)hexanoic acid were isolated as hydrochlorides and the hydrochlorides were converted to the zwitterion form using propylene oxide. The first stage of the developed scheme (preparation of pyridylalkanones) occurs in rather low yields, about 35 %. But, after the rearrangement, hydrolysis and the formation of zwitterion do not cause difficulties and are characterized by high yields. Consequently, the proposed synthetic sequence is preparatively advantageous.

Through N-acylation of a- or b-amino acid units by 2-(3-oxo-2,3-dihydro-1H-inden-5-yloxy)acetic acid using the method of N-hydroxysuccinimide esters new dipeptide indan-1-one derivatives were obtained. In general, the direct interaction of the acetic carboxyl group of the substrate with the amino group of the a- or b-dipeptide is a more productive strategy than the sequential peptidic condensation of the two amino acids.

International audience; A M8L2 metalla-cage constructed through coordination-driven self-assembly from a quinonato bis-ruthenium complex and an electron-rich tetrathiafulvalene (TTF) tetrapyridyl ligand is depicted. In this molecular box, both TTF units are highly bent and are separated by a distance as short as 3.48 Å in the solid state. This system offers a unique opportunity to study the electronic interactions occurring between two TTF units facing each other in a conformationally rigid environment.

Thin films containing luminescent active vanadate nanoparticles were applied by spin-coating, solution evaporation and pulsed laser deposition methods on glass substrates. The films are formed by pure vanadate layers as well as by silicon gel layers used as matrices and incorporated with vanadate nanocrystallites. Morphology of the films was studied using optical, atomic force and scanning electron microscopy. It was shown that films obtained from the same compositions but under different procedures have different morphology. Optical properties of the films were studied using absorption, reflection and luminescence spectroscopy in comparison with properties of the initial vanadate nanoparticles. Influence of procedure methods and growth conditions on spectral characteristics of the films was discussed. Advantages and disadvantages of the noted methods of luminescent films growing from vanadate nanoparticles were studied and discussed.

The EuVO$_4$ nanoparticles doped with Ca$^{2+}$ impurities were synthesized by citrate-nitrate sol-gel method and investigated. Diffuse reflection spectra of the EuVO$_4$:Ca samples contain two additional bands around 400 and 470 nm those were not observed for the undoped EuVO$_4$ . These bands were ascribed to Ca-induced defects in the vanadate crystal lattice. Origin of these defects is studied taking into account results of high resolution XRD measurements. The additive XRD peaks were found for the Eu$_{0.8}$Ca$_{0.2}$VO$_4$ , sample. These peaks were identified as traces of the Ca$_2$ V$_2$ O$_7$ second crystal phase in the synthesized nanoparticles. The maximal concentrations of the Ca$^{2+}$ heterovalent impurity permits to keep single phase EuVO$_4$:Ca sol-gel nanoparticles were estimated.

International audience; The development of methodologies to control on demand and reversibly supramolecular transformations from self-assembled metalla-structures requires the rational design of architectures able to answer to an applied stimulus. While solvent, concentration, guest, light, addition of a chemical have been largely explored to provide these transformations, the case of pH sensitive materials is less described. Herein, we report the first example of a pH-triggered dissociation of a coordination-driven self-assembled interlocked molecular link. It incorporates a pH sensitive benzobisimidazolebased ligand that can be selectively protonated on its bisimidazole moieties. This generates intermolecular electrostatic repulsions that reduces drastically the stability of the interlocked structure, leading to its dissociation without any sign of protonation of the basic pyridine moieties involved in the coordination bonds. Importantly, the dissociation process is reversible through addition of a base.

The vanadate-borate glass samples were synthesized by melt-quenching method and investigated. The glass compositions showed the best optical characteristics were incorporated with luminescent oxide nanoparticles. Structural and spectral properties of the glass and glass-ceramic composites were studied by XRD, SEM, reflection and luminescent techniques. Dependency of band gap energy on concentrations of glass components was studied using Kubelko-Munk transformations of the measured reflection spectra. Luminescent spectra of the activated glass-ceramic composites depend on matrix composition and method of incorporation of crystalline nanoparticles in the glass matrix. Conditions of synthesis and optimal ratios of the composites components those allow obtaining of samples promising for practical applications are discussed.

For the ternary system Ba-Cu-O, the polycrystalline samples with different Ba/Cu ratios were prepared at interaction between barium nitrate and copper (II) oxide. Using XRD phase analysis, have determined phase composition of the synthesized complex oxide and analyzed variation of powder diffractograms with thermal treatment time. It was found that formation of single-phase products occurs at Ba/Cu ratios 1: 1 and 2:3. The electrical properties of cuprates were studied with the impedance spectroscopy technique, while the oxygen index was determined using iodometric titration.

The Eu and Ca-doped LaVO 4 luminescent vanadate nanoparticles synthesized by sol-gel method have been successfully applied on silicon and solar cell substrates by pulsed laser deposition method for the first time. Morphology and structure of the obtained films were investigated. The films are formed by very small particles (up to 20 nm) and also can contain some agglomerates of nanoparticles. Optical properties of the samples have been studied and discussed. The vanadate films have caused improvement of antireflection properties of the used substrates. Luminescence spectra of the deposited films consist of spectral lines corresponded to f-f transitions in the Eu3+ ions. Spectra of the samples on solar cell substrates contain also very weak wide bands caused by emission of substrate. The optimal conditions of deposition of nanoparticles for obtaining of films promising for applications as luminescent spectral converters for improvement of efficiency of silicon solar cells are discussed.

Asymptotics for the electrostatic interaction energy between two point charges or dipoles located on a flat insulating (solid or liquid) surface or at the interface between two dielectric media were calculated analytically in the case of distances between the objects. Vertical and planar dipole alignments were considered. The spatial dispersion of the dielectric permittivities was taken into account, which resulted in a significant reduction of interaction in comparison with the classical case. The results were discussed in connection with the patterns exhibited by colloid particles on the liquid surface and at the interface between immiscible liquids. The presented theory can also be applied to the explanation of molecular patterns observed on the surfaces of solid insulators.

1-(Trimethylsilyl)vinyl MIDA boronate — a trifunctional C2 building block — is prepared in only two laboratory steps and 54% overall yield starting from readily available trimethyl(vinyl)silane. The title compound undergoes orthogonal functionalization at either of the groups present in its structure, for example, iodination at the trimethylsilyl moiety, epoxidation at the double bond, and Suzuki–Miyaura coupling at the MIDA boronate.

Condensation of bifunctional 1-aminoisoindole with bis-electrophilic methyl 4-chloro-3-oxobutanoate undergoes regioselectively to afford 2-(chloromethyl)-2-hydroxy-2,6-dihydro­pyrimido[2,1-a]isoindol-4(3H)-one. The structure of the reaction product was unambiguously established by HMQC and HMBC heteronuclear correlations. The functionalization of the synthesized compound by reactions with a series of aliphatic amines was carried out.

4-Amino-9-(2,5-dioxo-pyrrolidin-1-phenyl-3-yl)-1-phenyl-benzo[f]isoindole-1,3-dione (1) and 4-amino-9-(2,5- dioxo-1-(4-methylphenyl)-pyrrolidin-3-yl)-1-(4-methylphenyl)-benzo[f]isoindole-1,3-dione (2) were studied as fluorescent indicators for water determination in acetonitrile. The intensity of fluorescence of these compounds in acetonitrile solutions increases in presence of water along with red shift of the emission peak. Intensity-based and wavelength-based procedures of water determination in acetonitrile are suggested with detection limit of 0.2 % (v/v) H2O in both cases. The linear response covers a concentration range of 0.2–20 % (v/v). The relative standard deviation at 1 % (v/v) water content is 0.20. The interferences of acetic acid, ammonia and metal ions have been studied. Ammonia and acetic acid don’t interfere with the determination of water by wavelength-based fluorescence technique. In intensity-based mode the determination of water is possible at concentration of these impurities up to 0.25 and 0.02 mol·L -1, respectively. Cu(II) ions have almost no effect on fluorescence of indicators up to 1·10 -5 mol·L -1 ; Zn (II) ions enhance fluorescence of 1 at concentration ≥ 5·10-6 mol·L-1 . The 4-amino-benzo[f]- isoindole-1,3-dione-based fluorescent indicators are pH-insensitive.

A synthetical approach to acyl(N-methyliminodiacetyl)boronates starting from 1-substituted alkenylboronates has been developed. A comparison of different methods of oxidative cleavage of an α-borylated C-C bound was made. It was found, that the best results can be obtained by sequential osmium tetroxide-catalyzed dihydroxylation of an alkene moiety followed by cleavage of the obtained vicinal diol. The cleavage procedure takes place at 0°C in homogeneous conditions (solution of periodic acid in THF) and it is complete in 10 minutes (more prolonged contact with an oxidant solution results in degradation of the target compound). On the other hand, using of ruthenium tetroxide-based reagents results in overoxidation with simultaneous loss of boron moiety. Potassium permanganate protocols leads to the α-borylated-α-hydroxyketone, which is prone to further oxidation. Although 1-alkyl-vinylboronates react smoothly with 3-chloroperbenzoic acid to give corresponding oxiranes (without cleavage of C-B bound), the latter ones are stable toward action of sodium meta-periodate or periodic acid. The results were shown on the model compound – phenylacetyl MIDA boronate. Precursor of this compound, namely, Z-2-(N-methyliminodiacetylboryl)-1-phenylbut-2-ene was prepared in four steps, starting from common-use reagents with 32% overall yield. Thus the new approach allows acetyl MIDA boronates to be prepared just in 6 linear steps. It is remarkable, that mild and homogeneous conditions of the oxidation step permit to carry out this transformation on gram scale. A preliminary investigation of these substances stability towards common methods of working up and purification procedures was made. It was found, that phenylacetyl MIDA boronate and preceding diol, both are stable to storage at ambient conditions (tightly closed vessel, ambient temperature) at least for one month, showing no changes in its NMR spectra. Also, these compounds are stable to extractive work up with NaHCO3, Na2S2O3 and diluted acids. Stability toward chromatography on silica, prolonged contact with water or alcohols is limited. Structures and purity of compounds in this work was established by 1H, 13C – NMR and HPLC-analyses.

In our previous researches we have shown, that 1-aminoisoindole, which exists predominantly in isoindoline tautomeric form, can undergo [4+2]-cycloaddition reactions with maleimides according to the Curtin-Hammet principle. We continued to study this reaction, but with another dienophile – 1,4-naphtoquinone. In this case, the reaction does not stop when the bis-Michael adduct is obtained, but continues with the formation of a more complex compound, the structure of which we have studied by two-dimensional NMR spectroscopic methods.

The article represents the results of the research aimed to study the possible use of probiotics in the development of biotechnology for producing soft rennet cheeses with increased biotechnological value. The researchers found that the use of yeast consisting of L. Lactis and B. Subtilis made cheeses ripen faster and achieve the desired values of active and titratable acidity quicker. In control and experimental samples the ripening process took 8 hours while for other rennet cheeses with other probiotic consortiums including L. Lactis it took 12–14 hours to ripe. The addition of B. Subtilis to soft rennet cheese makes cells of probiotic cultures grow faster and more abundantly in comparison to the control sample. However, the microbiological analysis showed that at the end of the ripening process the number of L. Lactis bacteria cells, as well as B. Subtilis in experimental samples was higher than in the control sample by 0.5 and 1.2l g CFU/g respectively. The organoleptic evaluation showed that among seven samples of cheese the sixth sample had the best colour, smell, taste, consistency, pattern, and appearance. The sample had a sweetish cheesy taste, a tender homogeneous plastic consistency, a uniform white colour with holes of irregular, angular, slotlike, and oval forms of 1–2mm. The most rational concentration of Bacillus subtilis (strain 534) bacteria is 5 %. In this case 1ml contains 480 thousand microbial cells. This concentration gives a product a moderately marked cheesy, spicy taste that is inherent to soft cheeses. This indicates the feasibility of using Bacillus subtilis bacteria (strain 534) in the 5 % amount by milk weight.

Eight alkyl triarylstannanecarbodithioates were synthesized starting from the corresponding triarylstannyl chlorides. They were fully characterized by IR and 1 H, 13 C, and 119 Sn NMR spectroscopy and mass spectrometry. Their solid-state structures and geometric parameters were determined and compared to those of other classes of thiocarbonylthio compounds. These new organotin derivatives are efficient reversible chain-transfer agents for reversible addition-fragmentation chain transfer (RAFT) polymerization of styrene (St) and n-butyl acrylate (BA), with controlled number-average molecular weights and narrow dispersities (Ð