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A new pyridine-fused selenodiazolium salt, 3-(phenylselanyl)[1,2,4]selenadiazolo[4,5-a]pyridin-4-ylium chloride dichloromethane 0.352-solvate, C12H9N2Se2+·Cl−·0.352CH2Cl2, was obtained from the reaction between 2-pyridylselenenyl chloride and phenylselenocyanate. Single-crystal structural analysis revealed the presence of C—H...N, C—H...Cl−, C—H...Se hydrogen bonds as well as chalcogen–chalcogen (Se...Se) and chalcogen–halogen (Se...Cl−) interactions. Non-covalent interactions were explored by DFT calculations followed by topological analysis of the electron density distribution (QTAIM analysis). The structure consists of pairs of selenodiazolium moieties arranged in a head-to-tail fashion surrounding disordered dichloromethane molecules. The assemblies are connected by C—H...Cl− and C—H...N hydrogen bonds, forming layers, which stack along the c-axis direction connected by bifurcated Se...Cl−...H—C interactions.

The reaction between 2-pyridylselenenyl chloride and isobutyronitrile results in the formation of the corresponding cationic pyridinium-fused 1,2,4-selenodiazole, namely, 3-(propan-2-yl)-1,2,4-[1,2,4]selenadiazolo[4,5-a]pyridin-4-ylium chloride, C9H11N2Se+·Cl−, in high yield (89%). The structure of the compound, established by means of single-crystal X-ray analysis at 100 K, has monoclinic (P21/c) symmetry and revealed the presence of bifurcated chalcogen-hydrogen bonding Se...Cl−...H—Cl, and these non-covalent contacts were analysed by DFT calculations followed by a topological analysis of the electron-density distribution (ωB97XD/6-311++G** level of theory).

The purpose of the study is to analyze the morphological features of the Russian speech of two generations of Russian-German bilinguals living in Germany and Russian monolinguals living in Russia. The relevance of this study is due to the need to study the state of the Russian language abroad, its preservation and development. Four groups of informants took part in the study: 22 bilingual adults, 26 their children, 19 monolingual adults, 23 their children. The age of the parents is 35-50 years, the age of the children is 10-15 years. The material of the study was transcripts of audio recordings of oral stories based on pictures from the book by M. Mayer “Frog: where are you?”. Research methods are directed sampling, descriptive, systematization, statistical and comparative. Deviations from morphological norms were grouped into two structural types: 1) deviations from the norms of constructing word forms; 2) deviations from the norms of the choice of word forms. The study determined the average number of deviations from morphological norms in the stories of four groups of informants. It was found that in families seeking to preserve the Russian language in conditions of emigration, the morphological system remains relatively stable. At the same time, the average proportion of deviations from morphological norms in the speech of bilinguals is higher than in the speech of monolinguals, and in the speech of children is higher than in the speech of their parents. The average values of the number of typical deviations from the norms in each of the groups were determined. The heterogeneity of the number of deviations from the norms in individual representatives of each of the groups of informants was revealed. It is established that in some families the literary language is preserved, and the influence of the German language is not revealed, in others the vernacular is the means of communication, and some deviations from morphological norms may be caused by interlanguage interference. It should be noted that the greatest difficulty for all native speakers of the Russian language is the norms of the use of case forms and prepositional-case.

The study is devoted to the syntactic characteristics of the Russian speech at the level of a complex sentence of two generations of Russian-German bilinguals: the speakers of inherited Russian, aged 10-15, who were born in Germany or came to Germany at an early age, and their parents, aged 35-50, who moved to Germany in 1990-2010, and the Russian monolinguals of the same age, living in Russia. The relevance of the study is due to the importance of exploring complex sentences in oral speech, as well as the need to analyze the syntactic level of Russian speech of the inherited language speakers. The aim of the study is to analyze the deviations in using complex sentences in the stories of two generations of Russian-German bilinguals and to compare them with similar deviations in the stories of Russian monolinguals. Research material: transcripts of story recordings based on pictures from the book “Frog, where are you?” by M. Mayer. Linguistic observation, descriptive, statistical and comparative methods were applied. The average share of deviations from syntactic norms in the informants' stories was revealed, the violations were ranked according to their structural types. The most typical deviations, connected with the organization of a complex sentence parts, the use of connective and correlative words, were established. It is noted, that the speech of children has much more deviations from syntactic norms, than the speech of their parents. This fact is explained by a higher level of education of parents. In the speech of bilinguals, more deviations from syntactic norms were revealed than in the speech of monolinguals, which is caused by the different status of the Russian language in Germany and Russia. The conclusion is made about the perspective of the structural approach to the analysis of the syntactic features of the oral speech of different categories of Russian native speakers at the level of a complex sentence.

The molecular and crystal structures of the title compound, [Cu2I2(C18H12N2)2], were examined by single-crystal X-ray diffraction and Hirshfeld surface analysis. The Cu atom is coordinated in a distorted tetrahedral geometry by two N atoms from the 2,2′-biquinoline ligands and the two μ2-bridging iodide ligands. The molecules are in contact via π–π-stacking interactions. Hirshfeld surface analysis showed that the most important contributions to the intermolecular interactions are H...H (39.7%), H...I/I...H (17.8%), C...H/H...C (17.5%), C...C (16.5%), N...C/C...N (3.9%) and N...H/H...N (3.5%).

A new pyridine-fused selenodiazolium salt, 3-(phenylselanyl)[1,2,4]selenadiazolo[4,5-a]pyridin-4-ylium chloride dichloromethane 0.352-solvate, C12H9-N2Se2+ ·Cl ·0.352CH2Cl2, was obtained from the reaction between 2-pyridylselenenyl chloride and phenylselenocyanate. Single-crystal structural analysis revealed the presence of C—H...N, C—H...Cl, C—H...Se hydrogen bonds as well as chalcogen–chalcogen (Se...Se) and chalcogen–halogen (Se...Cl ) interactions. Non-covalent interactions were explored by DFT calculations followed by topological analysis of the electron density distribution (QTAIM analysis). The structure consists of pairs of selenodiazolium moieties arranged in a head-to-tail fashion surrounding disordered dichloromethane molecules. The assemblies are connected by C—H...Cl and C—H...N hydrogen bonds, forming layers, which stack along the c-axis direction connected by bifurcated Se...Cl- ...H—C interact [ABSTRACT FROM AUTHOR]

A new pyridine-fused selenodiazolium salt, 3-(phenylselanyl)[1,2,4]selenadiazolo[4,5-a]pyridin-4-ylium chloride dichloromethane 0.352-solvate, C12H9N2Se2+·Cl-·0.352CH2Cl2, was obtained from the reaction between 2-pyridylselenenyl chloride and phenylselenocyanate. Single-crystal structural analysis revealed the presence of C--H⋯N, C--H⋯Cl-, C--H⋯Se hydrogen bonds as well as chalcogen-chalcogen (Se⋯Se) and chalcogen-halogen (Se⋯Cl-) interactions. Non-covalent interactions were explored by DFT calculations followed by topological analysis of the electron density distribution (QTAIM analysis). The structure consists of pairs of selenodiazolium moieties arranged in a head-to-tail fashion surrounding disordered dichloromethane molecules. The assemblies are connected by C--H⋯Cl- and C--H⋯N hydrogen bonds, forming layers, which stack along the c-axis direction connected by bifurcated Se⋯Cl-⋯H--C interactions. [ABSTRACT FROM AUTHOR]

This work focuses on the first use of ultrasonic phenol-ene coupling as a polymer analogous transformation. The ultrasonic reaction was introduced into chitin chemistry, resulting in the fast and convenient preparation of new water-soluble cationic chitin derivatives. Since water-soluble derivatives of fully deacetylated chitin are poorly described in the literature, the synthesis of each new type of these derivatives is a significant event in polysaccharide chemistry. Polycations, or cationic polymers, are of particular interest as antibacterial agents. Consequently, the resulting polymers were tested for their antibacterial activity and toxicity. We found that the highly substituted polymer of medium molecular weight exhibited the most pronounced in vitro antibacterial effect. We prepared nanoparticles using the ionic gelation technique. The most effective in vitro antibacterial chitin-based systems were tested in vivo in rats. These tests demonstrated outstanding antibacterial effects combined with an absence of toxicity. Additionally, we found that the resulting polymers, unlike their nanoparticle counterparts, also exhibited strong antioxidant effects. In summary, we demonstrated the effectiveness of ultrasound in polymer chemistry and highlighted the importance of the sonochemical approach in the chemical modification of polysaccharides. This approach enables the synthesis of derivatives with improved physicochemical and biological properties. [ABSTRACT FROM AUTHOR]

In this study, we elaborated new chitosan-based films reinforced by iron(III)-containing chitosan nanoparticles Fe(III)-CS-NPs at different concentrations. We found that the optimum concentration of Fe(III)-CS-NPs for the improvement of antibacterial and mechanical properties of the films was 10% (σb = ca. 8.8 N/mm2, εb = ca. 41%, inhibition zone for S. aureus = ca. 16.8 mm and for E. coli = ca. 11.2 mm). Also, using the click-chemistry approach (thiol–ene reaction), we have synthesized a novel water-soluble cationic derivative of chitin. The addition of this derivative of chitin to the chitosan polymer matrix of the elaborated film significantly improved its mechanical (σb = ca. 11.6 N/mm2, εb = ca. 75%) and antimicrobial (inhibition zone for S. aureus = ca. 19.6 mm and for E. coli = ca. 14.2 mm) properties. The key mechanism of the antibacterial action of the obtained films is the disruption of the membranes of bacterial cells. The elaborated antibacterial films are of interest for potential biomedical and food applications.

The title compound, C23H19BrN4O2, is a product of an azo coupling reaction between 3,4-bis(4-methoxyphenyl)imidazole and 4-bromophenyldiazonium tetrafluoroborate. Its crystal structure was determined using data collected at 120 K. The molecule adopts a trans configuration with respect to the N=N double bond. The imidazole and aryl rings attached to the azo linkage are coplanar within 12.73 (14)°, which indicates significant electron delocalization within the molecule. In the crystal, the molecules form centrosymmetric dimers via pairs of N—H...O hydrogen bonds.

The title compound, C27H24N2O5, is a product of the deamination reaction from aza-14-crown-4 ether containing the γ-piperidone subunit. The title molecule contains a 16-membered macrocycle with the conformation of the C—O—C—C—O—C—C—O—C polyether chain being t–g(-)–t–t–g(+)–t (t = trans, 180°; g = gauche, ±60°). The dihedral angle between the planes of the benzene rings fused to the aza-14-crown-4-ether moiety is 31.11 (14)°. The cavity size inside the macrocycle is 4.72 Å. The macrocycle is significantly flattened as a result of the extended conjugated system. Steric repulsion between the pyridylcarboxamide fragment and the benzene ring results in a slight deviation of macrocycle from planarity. The structure also features intramolecular hydrogen bonding, which results in a deviation of the angle between the planes of amide and pyridyl groups from planarity: this angle is 16.32 (18)°. In the crystal, the molecules are linked into infinite zigzag chains via intermolecular C—H...π contacts. The chains are bound into layers parallel to (100) by weak intermolecular C—H...O hydrogen bonds.

Microorganisms, fermentation processes, and the resultant metabolic products are a key driving force in biotechnology and, in particular, in food biotechnology. The quantity and/or quality of final manufactured food products are directly related to the efficiency of the metabolic processes of producer microorganisms. Food BioTech companies are naturally interested in increasing the productivity of their biotechnological production lines. This could be achieved via either indirect or direct influence on the fundamental mechanisms governing biological processes occurring in microbial cells. This review considers an approach to improve the efficiency of producer microorganisms through the use of several types of substances or complexes affecting the metabolic processes of microbial producers that are of interest for food biotechnology, particularly fermented milk products. A classification of these supplements will be given, depending on their chemical nature (poly- and oligosaccharides; poly- and oligopeptides, individual amino acids; miscellaneous substances, including vitamins and other organic compounds, minerals, and multicomponent supplements), and the approved results of their application will be comprehensively surveyed.

The series of substituted 1,2,4-selenodiazolium tetraphenylborate complexes were synthesized via cyclization between 2-pyridylselenylchloride, followed by the anion metathesis, and fully characterized. The utilization of tetraphenylborate anion, a strong π-electron donor via its phenyl rings, promoted the formation of assemblies exhibiting selenium–π interactions. The chalcogen bonding (ChB) interactions involving the π-systems of the tetraphenylborate anion were studied using density functional theory (DFT) calculations, where “mutated” anions were used to estimate the strength of the Se···π chalcogen bonds. Moreover, molecular electrostatic potential (MEP) surfaces were used to investigate the electron-rich and poor regions of the ion pairs. The quantum theory of atoms-in-molecules (QTAIM) and the noncovalent interaction (NCI) plot methods based on the topology of the electron density were used and combined to characterize the ChBs. The investigation reported herein disclosed that the formation of symmetrical dimers can be broken by the introduction of a stronger π-acceptor and, consequently, forming stronger Se···π contacts with selenodiazolium cations.

Ciprofloxacin is one of the most effective antibiotics, but it is characterized by a range of side effects. Elaboration of drug-releasing systems which allow to diminish toxicity of ciprofloxacin is a challenging task in medicinal chemistry. The current study is focused on development of new ciprofloxacin releasing systems (CRS). We found that ultrasound efficiently promotes N,N′-dicyclohexyl carbodiimide-mediated coupling between COOH and NH2 functionalities in water. This was used for conjugation of ciprofloxacin to chitosan. The obtained ciprofloxacin/chitosan conjugates are capable of forming their self-assembled nanoparticles (SANPs) in aqueous medium. The SANPs can be additionally loaded by ciprofloxacin to form new CRS. The CRS demonstrated high loading and encapsulation efficiency and they are characterized by extended release profile (20 h). The elaborated CRS were tested in vivo in rats. The in vivo antibacterial effect of the CRS exceeded that of the starting ciprofloxacin. Moreover, the in vivo acute and subacute toxicity of the nanoparticles was almost identical to that of the chitosan, which is considered as the non-toxic biopolymer.

A practical method for the synthesis of 2-selenoxo-1,2,3,4-tetrahydro-4-quinazolinone was reported. The latter compounds were found to undergo facile oxidation with H2O2 into corresponding diselenides. Novel organoselenium derivatives were characterized by the 1H, 77Se, and 13C NMR spectroscopies, high-resolution electrospray ionization mass spectrometry, IR, elemental analyses (C, H, N), and X-ray diffraction analysis for several of them. Novel heterocycles exhibited multiple remarkable chalcogen bonding (ChB) interactions in the solid state, which were studied theoretically.

The bis(anil) molecule of the title compound, C47H32N2O2·C6H4Cl2, contains two anil fragments in the enol–enol form, exhibiting intramolecular O—H...N hydrogen bonds. The two hydroxynaphthalene ring systems are approximately parallel to each other with a dihedral angle of 4.67 (8)° between them, and each ring system makes a large dihedral angle [55.11 (11) and 48.50 (10)°] with the adjacent benzene ring. In the crystal, the bis(anil) molecules form an inversion dimer by a pair of weak C—H...O interactions. The dimers arrange in a one-dimensional column along the b axis via another C—H...O interaction and a π–π stacking interaction between the hydroxynaphthalene ring system with a centroid–centroid distance of 3.6562 (16) Å. The solvent 1,2-dichlorobenzene molecules are located between the dimers and bind neighbouring columns by weak C—H...Cl interactions. Theoretical prediction of potential biological activities was performed, which suggested that the title anil compound can exhibit histone deacetylase SIRT2, histone deacetylase class III and histone deacetylase SIRT1 activities, and will act as inhibitor to aspulvinone dimethylallyltransferase, dehydro-l-gulonate decarboxylase and glutathione thiolesterase.

The synthesis and structural characterization of α-haloalkyl-substituted pyridinium-fused 1,2,4-selenadiazoles with various counterions is reported herein, demonstrating a strategy for directed supramolecular dimerization in the solid state. The compounds were obtained through a recently discovered 1,3-dipolar cycloaddition reaction between nitriles and bifunctional 2-pyridylselenyl reagents, and their structures were confirmed by the X-ray crystallography. α-Haloalkyl-substituted pyridinium-fused 1,2,4-selenadiazoles exclusively formed supramolecular dimers via four-center Se···N chalcogen bonding, supported by additional halogen bonding involving α-haloalkyl substituents. The introduction of halogens at the α-position of the substituent R in the selenadiazole core proved effective in promoting supramolecular dimerization, which was unaffected by variation of counterions. Additionally, the impact of cocrystallization with a classical halogen bond donor C6F3I3 on the supramolecular assembly was investigated. Non-covalent interactions were studied using density functional theory calculations and topological analysis of the electron density distribution, which indicated that all ChB, XB and HB interactions are purely non-covalent and attractive in nature. This study underscores the potential of halogen and chalcogen bonding in directing the self-assembly of functional supramolecular materials employing 1,2,4-selenadiazoles derived from recently discovered cycloaddition between nitriles and bifunctional 2-pyridylselenyl reagents. [ABSTRACT FROM AUTHOR]

In this study, Rhodamine B-containing chitosan-based films were prepared and characterized using their mechanical, photophysical, and antibacterial properties. The films were synthesized using the casting method and their mechanical properties, such as tensile strength and elongation at break, were found to be dependent on the chemical composition and drying process. Infrared spectroscopy and X-ray diffraction analysis were used to examine the chemical structure and degree of structural perfection of the films. The photophysical properties of the films, including absorption spectra, fluorescence detection, emission quantum yields, and lifetimes of excited states, were studied in detail. Rhodamine B-containing films exhibited higher temperature sensitivity and showed potential as fluorescent temperature sensors in the physiological range. The antibacterial activity of the films was tested against Gram-positive bacteria S. aureus and Gram-negative bacteria E. coli, with Rhodamine B-containing films demonstrating more pronounced antibacterial activity compared to blank films. The findings suggest that the elaborated chitosan-based films, particularly those containing Rhodamine B can be of interest for further research regarding their application in various fields such as clinical practice, the food industry, and agriculture due to their mechanical, photophysical, and antibacterial properties. [ABSTRACT FROM AUTHOR]

Aim. To improve the results of surgical treatment of patients with esophageal diverticulum of various localization using intraoperative intraluminal endoscopy. Materials and Methods: The Department of Surgery of the Esophagus and Stomach, the Petrovsky National Research Centre of Surgery, has accumulated a large experience in treating diverticulosis patients. Thus, during the 2010–2018 period, 74 patients with esophageal diverticula of various localization were operated. Out of them, 56 (75.7 %), 10 (13.5 %) and 8 (10.8 %) patients underwent surgical treatment with respect to faringo-esophageal, bifurcation and epiphrenic diverticula, respectively. The patients were divided into two groups: 31 people (41.9 %) in the main group underwent diverticulectomy with intraoperative intraluminal endoscopic assistance (IVEA), while 43 (58.1 %) people in the control group underwent diverticulectomy without IVEA. Intraoperatively, at the stage of discovering diverticulum, the endoscopist applied transillumination and air insufflation in the cavity of the diverticulum, followed by controlling the mobilization of diverticulum. At the resection stage, the completeness of the surgical removal was controlled, along with the absence of esophageal lumen narrowing after sewing the neck of the diverticulum using a linear stapler.Results. The average duration of the operation in patients with Zenker’s diverticula and those in the control group was 45.5 ± 8.8 min and 73.8 ± 12.7 min (p < 0.05), respectively. In patients with the diverticula of the middle and lower third of the esophagus, the average surgery duration was equal to 120.3 ± 11.2 min and 150.5 ± 17.3 (p

Nitro functionalized dibromodiazadiene dyes were prepared and fully characterized including X-ray single crystal analysis. Electron deficient dibromodiazadienes were found to be able to act as donors of halogen bonding (XB), while the nitro group acted as an acceptor of the XB. Depending on the substituents, the Br···O XB competed with other weak interactions, and for some of the dyes, they even outcompeted the XB involving the nitro group. However, the nitro functionalized dibromoalkenes 6a and 10a, which had only the nitro moiety as the most plausible acceptor of the XB, reliably formed 1D chains via Br⋯O XB. Experimental work was supported by the DFT calculations and topological analysis of the electron density distribution within the framework of Bader’s theory (QTAIM method).

The aim of this prospective randomized clinical study was to investigate the role of preoperative carbohydrate admnistration in surgery-induced metabolic, immune and inflammatory reactions after thoracoabdominal operations. At the Surgical department I (B.V. Petrovsky National Research Center of Surgery), we investigated a modulatory role of carbohydrate preload upon surgical stress observed after major thoracoabdominal operations (thoracoscopic and open esophagectomy, retrosternal colonic esophagoplasty) followed by the enhanced recovery protocol. The study was performed in 2014-2017, it included 30 patients, divided into 2 groups. Group A patients (n = 16) received carbohydrates preload (12.5% maltodextrin solution per os or enterally). In patients with dysphagia, the 12.5% dextrose solution was used intravenously in equal volumes. Group B patients didn’t receive any additional preload with carbohydrates. The groups were age- and gendermatched, similar for disease and surgery types. Glucose and insulin levels (with HOMA insulin resistance index, HOMA-IR) were measured before surgery and on day +1, interleukin levels (IL-6, IL-10, IL-8) and index IL-8/IL-10 were assessed before surgery, and on days +1 and +5 after surgery. Cell-mediated immunity was investigated before surgery and on day +5.The stress-induced hyperglycemia (> 7.8 mmol/L) was detected more frequently in group B (50%), than in group A (6%), p = 0.012. Insulin resistance measured by HOMA-IR in group B was detected in 71% of patients and in 25% patients of group A only, p = 0.027. Individual analysis of immune response demonstrated that a trend for immune recovery was detected by the day +5 post-op in the group A. Postoperative levels of IL-6 and IL-10 were lower on day +1 and +5 in group A. Morbidity rates and the terms of hospitalization were similar in both groups. Local postsurgical infections in group A were developed in 6% of the patients vs 35.6% in group B (p = 0.072).In conclusion, a complex study of surgical stress, i.e., metabolic, immune and inflammatory reactions after esophageal surgery has shown that the carbohydrate preload decreased the incidence of postoperative insulin resistance and stress-induced hyperglycemia, being accompanied by lower release of proinflammatory cytokines and provides positive effects upon the patient’s immune system.

Novel triarylazoimidazoles containing strong electron donors (p-NEt2) or acceptors (p-NO2) by the azoaryl group, and their group 12 metal complexes were synthesized and fully characterized, including X-ray analysis for several complexes. Novel complexes exhibit red photo-luminescence emission (Φ up to 0.21) in a solution. Moreover, the antibacterial activity of complexes was tested against Gram-positive microorganism S. aureus and Gram-negative microorganism E. coli.

Gold(I) isocyanide complexes featuring Au···Au interactions attract considerable attention because of their tunable photophysical properties. Although the synthetic exploration of isocyanide gold(I) complexes seems reasonable, their structural diversity is mainly limited to linear gold(I) derivatives. The synthesis and structural characterization of cationic three-coordinate gold(I) mixed 2,2′-bipyridyl/isocyanide complex are presented here for the first time. Cationic gold species form supramolecular dimers in the solid state via attractive Au···Au interactions. The nature and energies of aurophilic contacts, which are responsible for dimerization in the solid state, were studied by DFT calculations together with QTAIM, ELF, RDG, and NCI techniques and Hirshfeld surface analysis. The estimated energy of the aurophilic interactions was 6.3 kcal/mol.