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A POPOP analogue was synthesized using a progressive atom-economical click reaction with high yield. The resulting compound has similar photophysical properties compared to POPOP. The synthesized analogue has emission with a bathochromic shift. [ABSTRACT FROM AUTHOR]

10-(4,5-di-p-Tolyl-1H-1,2,3-triazol-1-yl)-2,3-dimethoxypyrido[1,2-a]indole 2 was obtained by interaction of 5,6-di-p-tolyl-3-(2-pyridyl)-1,2,4-triazine 1 with 4,5-dimethoxydehydrobenzene. The fluorescence properties of the compound 2 in the presence of nitroaromatic compounds were studied. [ABSTRACT FROM AUTHOR]

Two approaches towards "turn off" fluorescence detection of nitroanalytes (dinitro-ortho-cresol (DNOC), 2,4,6-trinitrotoluene (TNT) and Riamilovir (Triazavirin ®) are reported such as by tuning the chemosensors structure or by changing the environment. In both cases the great response was achieved with Stern-Volmer quenching constants (KSV) as high as 2.28–3.14 × 104 M−1 (for structure modification approach) and 4.67 × 105 M−1 (for changing of environment approach). [ABSTRACT FROM AUTHOR]

In laboratory conditions, we simulated furfural production from sunflower husk with a particle size of 6-10 µm. Furfural is one of the most common types of waste included in the top ten waste containing more than 25% pentosans. Besides, it is a convenient model, since it represents the accumulation of industrial waste with a low cost and composition typical of straw and wood materials. We focused on sunflower husk as raw materials, and for obtaining desired products, the three-stage process was used. This process involves the milling of raw sunflower husk to obtain particles up to 6-10 µm in size by using Retsch PM100 planetary mill, acid hydrolysis of the obtained particles in dilute sulfuric acid, and, finally, the multiple steam distillation of the reaction mixture. [ABSTRACT FROM AUTHOR]

1-Pyrenmagnesium bromide (Grignard reagent) was prepared in situ from 1-bromopyrene, and was successfully used for the syntheses of 1-pyrenecarbaldehyde and 1-pyrene carboxylic acid under mild conditions with high yields. [ABSTRACT FROM AUTHOR]

Nanophosphors in the amorphous state was first obtained by electron beam evaporation of bulk phosphors with an oxyapatite structure of the composition Sr2La8(1-x-y)ErxYbyGe6O26(x = y = 0.01÷0.15). A modification of the Raman spectrum was detected with a decrease in particles from the micro- to nanoscale state. The luminescent characteristics of the samples in micro- and nanostates were studied. The dependences of the luminescence intensity of nanophosphors for some transitions on the pump radiation power are analyzed. A laser pump critical power of ∼75 mW was found for the lines caused by the 4S3/2→4I15/2, 4S3/2→4I15/2 and 4I9/2→4I15/2 transitions. The effect of the cross-relaxation of the 4I11/2+4I11/2→4I15/2+4F7/2 state on the 4I11/2 level of the Er3+ ion has been established. This process is dominant, equally affects the filling of the 2H11/2, 4S3/2, and therefore level 4F9/2. [ABSTRACT FROM AUTHOR]

A new supramolecular complex of triterpene glycoside hederasaponin C (HedC) with flavonol quercetin (Quer) was obtained. The synthesis of Quer–GC complex was carried out in the liquid phase. The complexation was studied by ATR IR-Fourier spectroscopy and the method of isomolar series. The hydrogen bonds of types –(H)O...H–O– and –C=OQuer...H–O–HedC are formed in the molecular complex. [ABSTRACT FROM AUTHOR]

A new 1 : 1 molecular complex of glycyram (monoammonium salt of glycyrrhizic acid, GC) with salicylic acid (SalA) was obtained. The synthesis of SalA–GC complex was carried out in the liquid phase. The complexation was studied by the method of isomolar series in the spectrophotometric version and ATR IR-Fourier spectroscopy. It was shown that H-bonds are formed between the components of the complex (–C = OGC...HOOC–SalA and –(H)OGC...HOOC–SalA). Hydrophobic contacts of GC with SalA molecules are possible. [ABSTRACT FROM AUTHOR]

We herein report the synthesis of a series of novel pharmacologically relevant coumarins linked with amides. The three-step methodology was found to be facile and compatible with a range of aryl and heteroaryl amines leading to the diverse arena of amides of considerable pharmacological relevance. [ABSTRACT FROM AUTHOR]

The study is devoted to the detailed investigation of the ipso-chlorination reaction of calixarenes and search of an optimal combination of chlorinating reagents. This factor was varied in a number of experiments. It was established that the presence of sulphuryl chloride and the acidic proton is a necessary condition for successful ipso-chlorination of calix[4]arenes. The addition of any of phosphorus chlorides accelerates reaction speed and increases process yield. So the most promising chlorination mixture was that SO2Cl2 (4 eq.), POCl3 (1 eq.) and glacial acetic acid (1 eq.) which provided 64% yield of the desired compound after two days of the experiment. [ABSTRACT FROM AUTHOR]

The synthesis technology of porous silicon allows obtaining particles with significantly different properties. This article shows that porous silicon particles exhibit different toxic effects on eukaryotic microorganisms (for example, ciliates Paramecium caudatum Ehrenberg, 1838) due to the different influence of parameters: the diameter of the nanoparticles, type of conductivity. The research results are relevant for the use of porous silicon particles as transport systems for targeted drug delivery. [ABSTRACT FROM AUTHOR]

The strategy of metal-free nucleophilic addition of indoles to carborancarboxaldehyde has first been applied to afford novel boron-enriched 3-indolylmethanols that are of particular interest in the medicinal chemistry and materials science. [ABSTRACT FROM AUTHOR]

A series of new D-π-A chromophores containing a triphenylamine fragment as a terminal electron-donating group, as well as (5,5-dimethylcyclohex-2-en-1-ylidene) propanedinitrile or (6-methyl-4H-pyran-4-ylidene) propanedinitrile fragments as an acceptor. A comparative analysis of the optical and electrochemical properties of the obtained compounds is carried out. It was found that the replacement of the (5,5-dimethylcyclohex-2-en-1-ylidene) propanedinitrile fragment with a (6- methyl-4H-pyran-4-ylidene) propanedinitrile fragment leads to a slight increase in the bandgap of the compound, while the coefficient increases significantly molar absorption, as well as the quantum yield of luminescence. [ABSTRACT FROM AUTHOR]

Imidazolium Zwitterionic Molten Salt, an efficient green organo-catalyst, has been introduced for the three- component one-pot reaction of aldehyde, amine, and an alkyne to produce propargyl amines. By this protocol, we can avoid heavy metals, solvent and obtain the propargylamine in excellent yields. The molten salt can be recycled several times without any significant loss in its catalytic activity. [ABSTRACT FROM AUTHOR]

An efficient synthesis of 3-(1-(4-halobenzyl)-1H-1,2,3-triazol-4-yl)-9-alkyl-9H-carbazole has been developed in click chemistry approach by reacting 1-(Azidomethyl)-4-halobenzene and 3-Ethynyl-9-alkyl-9H-carbazole in presence of sodium ascorbate. The effective catalyst and solvent have been optimized by investigations and found that the desired product was effectively formed with CuSO4.5H2O as a catalyst in DMF. Then reaction has been employed for the synthesis of a library of analogues under the optimized conditions and obtained them in moderate to good yields. All the compounds were characterized by the spectral (IR, 1HNMR, 13CNMR, Maas) and elemental (C, H, N) analysis. [ABSTRACT FROM AUTHOR]

2-(2-(4-(3-Carboxy-1-ethyl-6-fluoro-4-oxo-1,4-dihydroquinolin-7-yl)piperazin-1-yl)-2-oxoethyl)-2- hydroxysuccinic acid (2) and 3-(4-(3-carboxy-1-ethyl-6-fluoro-4-oxo-1,4-dihydroquinolin-7-yl)piperazine-1-carbonyl)- 3-hydroxypentanedioic acid (3) derivatives, a class of norfloxacin analogues of dimethyl citrate conjugates have been synthesized. They were synthesized and characterized by 1H NMR, 13C NMR, IR, Mass, elemental analysis and their molecular modeling studies, antibacterial and anticancer activities have been assessed. Screening results indicate that compound 2 possess good antibacterial activity against several microorganisms, with MIC values in the range of 0.16-0.35 mg/mL and MBCs in the range of 0.55‒0.84 mg/mL. Experiments indicated that 3, the regioisomer of 2 demonstrated the most significant activity towards the human colon cancer cell line (HCT‒15) with IC50 value 8.2 and against human colorectal adenocarcinoma cell line (HT‒29) with IC50 8.9. Fascinated by the results, the title compounds were designed and evaluated for molecular and pharmacokinetic properties prediction, drug-likeness model scores by using Molinspiration-2008 and MolSoft-2007. The regioisomeric citrate conjugates followed Lipinski's 'Rule of five' and can be considered as potential antibacterial and anticancer bioavailable oral leads. [ABSTRACT FROM AUTHOR]

The aim of this study was the determination of the optimal ratio of vinpocetine and polyvinylpyrrolidone in the drug formulation ((1:2 or 1:5) according to the results of simulation by molecular dynamics technique concerning the release of the reactant into an aqueous medium. Molecular dynamics simulation for the release of vinpocetine from polyvinylpyrrolidone was performed for 100 nanoseconds with the use of Gromacs 2019 computer program in the force field Gromos 54a7. As a result, it was found that the equilibrium under release of vinpocetine from polyvinylpyrrolidone is ensued more rapidly for the ratio of vinpocetine to the carrier equal to 1:5, as compared to the ratio of 1:2. [ABSTRACT FROM AUTHOR]

The work is concerned with the simulation of the assembly process for liposome from phospholipids of soya lecithin in the presence of vinpocetine using molecular dynamics technique as well as simulation of molecular dynamics for the vinpocetine release from liposome in the aqueous medium. For the simulation of liposomes, a coarse-grain molecular dynamics technique was applied in the force field of Martini 2.2 with the use of Gromacs 2016.4 program suite. According to the results of simulation, it was found that the formation of liposomes with spherical shape from the purified soya lecithin in the aqueous medium occurred spontaneously at the concentration of lecithin of 5 mass% at the temperature of 298 R during 3 µs. The release of vinpocetine into the aqueous medium from the surface of the liposome is quite insignificant. Vinpocetine excess on the surface of liposome in the aqueous medium is of 1.099*10−7±1.13*10−9 mole/m2. [ABSTRACT FROM AUTHOR]

Alumina ceramic doped with Mg and Cr is produced at high-temperature sintering under vacuum at varying annealing temperature and dopant concentration. A differential thermal analysis, X-ray fluorescence, and X-ray diffraction methods are used for sample characterization. The effect of the characteristics described above on the formation of different defects and luminescence centers in the samples was studied with a thermoluminescence method. An increase in the dopant concentration leads to an increase in the pulsed cathodoluminescence intensity of the dopant center in Mg-doped alumina ceramics and a decrease in Cr-doped alumina ceramics. The thermoluminescence intensity for Al2O3:Mg ceramics increases with magnesium concentration growth. The highest thermoluminescence intensity under a pulsed electron beam was obtained for ceramics with chromium (0.1 wt. %) annealed under vacuum at the temperature of 1500 °C for 2 hours. On thermoluminescence curves, one isolated peak at a temperature in the range of 645–665 K was registered. [ABSTRACT FROM AUTHOR]

In order to create water-soluble non-toxic derivatives of the antitumor antibiotic daunomycin, two methods for the synthesis of organo-inorganic complexes based on daunomycin, polyvinylpyrrolidone, and selenium nanoparticles have been developed. The first method consisted of the preliminary stabilization of selenium nanoparticles with polyvinylpyrrolidone, followed by the addition of daunomycin. The second method was implemented by the preliminary formation of a complex between daunomycin and polyvinylpyrrolidone followed by the reaction of selenium reduction. The methods of optical spectroscopy, dynamic and static light scattering showed the possibility of changing the internal structural organization and size of the complexes. [ABSTRACT FROM AUTHOR]

Natural supramolecular complexes gain much attention of researches at nature-Like and biotechnologies due to their incomparably high efficiency. Cyanobacteria, as the ancient photosynthetic microorganisms, have a perfect mechanism for harvesting and converting solar energy. The effectiveness of their light-harvesting complex is near unity and exhibit multifarious self-fluorescent properties. The last intrinsic natural feature is essential for the fluorescent non- destructive analysis of the structure and functioning of supramolecular pigment-protein complexes on a single-cell level and gives a unique opportunity for steady-state and time-resolved investigations of living cyanobacterial cells in vivo. In this work, the advanced methods of fluorescent spectroscopy (i.e. confocal microscopic spectroscopy and excitation- emission fluorescence spectroscopy) are used to study natural pigment-protein complexes in connection with their possible application in biosensorics and green energy production. [ABSTRACT FROM AUTHOR]

A series of imidazolyl benzamides containing urea has been subjected to molecular docking studies against DNA Gyrase enzyme. Most of the molecules exhibited appreciably high binding energy with the protein when compared to the reference drug, Ciprofloxacin. [ABSTRACT FROM AUTHOR]

It was found that erythromycin sorption on molecularly imprinted sorbents with different architecture carried out in a quasi-equilibrium regime. Molecular imprinting of the polymer matrix led to an improvement in the diffusion mass transfer of erythromycin molecules into monolithic MIPS. As a result, the possibility of using molecularly imprinted monolithic polymeric sorbents for the effective extraction of small molecules from a constantly renewed solution was shown. [ABSTRACT FROM AUTHOR]

The purpose of this study was the determination of the optimal ratio of vinpocetine and β-cyclodextrin in the drug formulation (1:2 or 1:5) according to the results of simulation of molecular dynamics of the reactant release into an aqueous medium. Molecular dynamics simulation for the release of vinpocetine from ß-cyclodextrin was performed for 100 nanoseconds with the use of Gromacs 2019 computer program in the force field Gromos 54a7. The equilibrium under release of vinpocetine from the studied carrier is ensued more rapidly for the ratio of vinpocetine to the carrier equal to 1:5, as compared to the ratio of 1:2. The efficiency of vinpocetine release for pH 2,0 is higher as compared with its release in the neutral medium. [ABSTRACT FROM AUTHOR]

The work is devoted to obtaining a new functional material by the graft polymerization method. Methacrylic acid adamantyl ester was used as the graftable monomer. The regularities of the process were studied in order to obtain the maximum yield of grafted copolymers. The proposed method allows to obtain a material containing up to 33% of grafted fragments in a modified fiber. The study of the properties showed that the obtained functional polymer material has good mechanical properties and increased heat resistance. [ABSTRACT FROM AUTHOR]

Adsorption at water – air interface and micelle formation in water for nonionic gemini surfactants Dynol® 600 series with different degree of oxyethylation (5 and 6, respectively) and Surfynol® 2502 were investigated. Colloid- chemical properties of surfactants given were studied, their adsorption characteristics were experimentally determined. The decrease in the oxyethylation degree results in an increase in surface activity. The influence of the propoxylated group on these characteristics is ambivalent. Gemini surfactants have higher surface activities in comparison with monomeric surfactants (sodium lauryl sulfate and sodium Laureth sulfate). The wetting ability of Dynol® 600 series and Surfynol® 2502 on Teflon surface was studied. The decrease of the surfactant oxyethylation degree of Dynol® 600 results in improvement of wetting properties. Surfynol® 2502 takes an intermediate position among them. For gemini surfactants examined cloud point dependence from the oxyethylation degree is typical for ethoxylated nonionic surfactants. [ABSTRACT FROM AUTHOR]

Wetting of low-energy surfaces (teflon) by the aqueous solutions of binary mixtures of nonionic gemini surfactants Surfynol® 400 series with different degree of oxyethylation (30, 10, 3.5 and 1.3, respectively) with the anionic one sodium lauryl sulfate at the molar fraction of Surfynol® α=0.2, 0.4, 0.6 and 0.8 was studied in the wide concentration range. The extent of mutual enhancement of the wetting ability depends on the oxyethylation degree of nonionic gemini surfactant and its molar fraction in the mixture. This phenomenon was shown in all concentration ranges except binary mixtures at the molar fraction of Surfynol® α = 0.8 at concentrations higher than their CMC values. [ABSTRACT FROM AUTHOR]

Adsorption at the water – air interface and micelle formation in water in binary mixtures of nonionic gemini surfactants Surfynol® 400 series with different degree of oxyethylation (30, 10, 3.5 and 1.3, respectively) and short rigid spacer with triple –C≡C– bond and anionic surfactant of sodium lauryl sulfate were investigated. Their critical micelle concentration (CMC) values were experimentally determined. CMC values of binary mixtures are lower than thats of either surfactant by itself which shows non-ideal behavior of surfactant molecules in micelles. The values of interaction parameters in mixed micelles βm were calculated using the Rubingh thermodynamic approach, the compositions of mixed micelles Xm were determined. The higher surface activity and the lower are the CMC values of the gemini surfactants Surfynol®, the higher are its part in the mixed micelles and the range of molar fraction of Surfynol® within which the mixed micelles is enriched with it. The negative values of the interaction parameters βm and the fulfillment of the condition |ln (C1m/C2m)| < |βm| submit synergism in mixed micelle formation in binary surfactants mixtures studied. The parameter value depends on the oxyethylation degree of nonionic surfactant. The reason is that the gemini surfactant' oxyethyl chains interact with the sodium cation of sodium lauryl sulfate like crown ethers and transformation of the nonionic surfactant into the associated cationic one which is capable to electrostatic interaction with the anionic surfactant followed by molecules mutual attraction. It is also a fact that the gemini surfactants studied have a specific molecular structure. They have a short rigid spacer which sets a limit on the mutual disposition of the oxyethyl chains. [ABSTRACT FROM AUTHOR]

Composite Au@Pt nanoparticles were synthesized by the reduction of Pt4+ on gold nanoparticles (GNP) using ascorbic acid. Varying the concentration of Pt4+ (20-2000 µM), homogenous nanoparticles with sizes ranging from 20 to 55 nm were synthesized. Transmission electron microscopy and energy-dispersive electron spectroscopy indicated the formation of hierarchically-shaped nanoparticles composed from GNP cores and Pt shells. The measurement of the nanoparticles' surface roughness by atomic force microscopy confirmed the formation of spiky Pt shells on smooth GNPs. As synthesized, Au@Pt nanoparticles possessed peroxidase- and catalase-mimicking activities. In comparison with horseradish peroxidase, Au@Pt nanoparticles were more stable at elevated temperatures (up to 90 °C). Synthesized Au@Pt nanoparticles possess high optical and catalytic properties, these nanoparticles are prospective as labels for various analytical techniques. [ABSTRACT FROM AUTHOR]

Synthesis of benzothiazole which involves the condensation of o-aminothiophenols with substituted aldehydes in the presence of Brønsted acidic ionic liquid (BAIL) without any solvent and room temperature. The present protocol considers having a wide range of substrate scope in a greener manner. [ABSTRACT FROM AUTHOR]

Novel granular organic-inorganic molecularly imprinted polymers (MIPs) based on 2-hydroxyethyl ethacrylate (HEMA) and ethylene glycol dimethacrylate (EGDMA) were prepared by copolymerization on the surface of selenium (Se) nanoparticles stabilized with poly(vinyl pyrrolidone) (PVP) at different concentrations of cholesterol as a template molecule. The synthesis occurred in Pickering microemulsion. The obtained compounds are intended for use as selective hemosorbents in efferent therapy of hypercholesterolemia. The sorbents were characterized by scanning electron microscopy (SEM) and sorption experiments. It was revealed that MIPs possess a more pronounced porous structure as compared to that of the reference non-imprinted polymer (NIP). The influence of the amount of introduced cholesterol template on physico-chemical and sorption properties of MIPs was investigated. Formation of the surface sorption layer in the MIPs facilitates the availability of imprint sites and enhances the efficiency of specific cholesterol binding from blood plasma in vitro. [ABSTRACT FROM AUTHOR]

Although Lipinski's rule of five is considered as a default measure of oral drug-likeness of compounds having an acceptable range of ADME and toxicity, many molecules that satisfy these conditions are by no means drug-like. Therefore, In Silico model for predicting oral bioavailability is very important, both in the early stage of drug discovery to select the most promising compounds for further optimization and in the later stage to identify candidates for further clinical development. In the present investigation, a series of ten novel dialkyl (((1-(substituted phenyl)-1H-1,2,3-triazol-4-yl)methoxy)(phenyl)methyl)phosphonate derivatives were subjected to molecular properties prediction, drug-likeness by Molinspiration (Molinspiration, 2019) and MolSoft (MolSoft, 2019) software and found that compound b as effective. [ABSTRACT FROM AUTHOR]

Ag nanoparticles were synthesized on the surface of SnO2 and ZnO by photoreduction from an aqueous solution of silver nitrate and borohydride reduction, respectively. The influence of synthesis conditions on particle sizes was analyzed by atomic force microscopy. The study of gas-sensitive properties of Ag-ZnO composites showed that their response to isopropyl alcohol vapors enhanced compared to pure zinc oxide. [ABSTRACT FROM AUTHOR]

Chitosan is capable to be broken down during physical, chemical and enzymatic cleavage. Products of chitosan decomposition have biological activities and therefore great potential applications in various industries. Particularly, glucosamine, as a valuable final product, has the beneficial pharmacological effects to relieve osteoarthritis symptoms and can also be as a promising candidate for the prevention and/or treatment of some other diseases due to its antioxidant and anti-inflammatory activities. In the present study, we performed hydrolysis of chitosan using the following soluble complex enzymatic preparations: Amylosubtilin, GlucoLux-F, Protosubtilin, CelloLux-A, CelloLux-F produced by Sibbiopharm Ltd, Russia. Amylosubtilin had demonstrated the highest catalytic activity. So, we carried out immobilization of Amylosubtilin on powdered alumina in the gamma phase (γ-Al2O3) modified with the following silane binding agents such as trimethoxymethylsilane (TMOMS), 3-aminopropyltriethoxysilane (APTES), 3-(2,3-epoxy-propoxy) propyl-trimethoxysilane (EPPMS), 3-mercaptopropyl-trimethoxysilane (MPP-TMOS). Also, we immobilized this enzymatic preparation on γ-Al2O3 modified with APTES by covalent binding through glutaraldehyde. The catalytic activity of soluble and immobilized enzymatic preparations was determined in U (U or μmol/min), where 1 U releases 1 µmol of glucosamine from chitosan per minute at pH 5.0 and 50 °C measured using the Elson-Morgan method. The biocatalytic system based on γ-Al2O3 showed the highest immobilization yield (60,6 %), whereas the highest catalytic activity was showed by the system based on γ-Al2O3 modified with APTES, it was higher than that for soluble Amylosubtilin, i.e. 0.0099378 U and 0.0037209 U, respectively. [ABSTRACT FROM AUTHOR]

Zinc stannate is a semiconductor compound which, due to its attractive properties, has found application in various fields (gas sensors, catalysis, solar cells, etc.). In this work, the structures of zinc hydroxostannate were synthesized, and the transition "zinc hydroxostannate (ZHS) – zinc stannate (ZTO)" was studied during further thermal or UV treatment. Investigation of obtained structures was carried put via X-Ray diffraction analysis, scanning electron microscopy SEM, acid-base indicators adsorption method. [ABSTRACT FROM AUTHOR]

The review presents data on the biological activity (cytotoxic and antiviral, in particular) of semi-synthetic C(3) alkylated triterpenoids of the lupane and oleanane types in combination with the results of the structure-activity relationship (SAR) analysis. [ABSTRACT FROM AUTHOR]

The anion-exchange material based on silica gel with covalently immobilized imidazolium salt can be used as a stationary phase upon separation and determination of anion in the model mixture by non-suppressed ion chromatography. [ABSTRACT FROM AUTHOR]

As potential HDAC inhibitors, new derivatives of 1,2-dihydroquinazolin-4-one in combination with alkyl hydroxamic acid have been proposed. The latter were obtained by the interaction of an alkyl hydroxyamide derivative of anthranilamide with various aldehydes by boiling in ethanol with yields of 73-99% and were characterized by 1H-NMR and ESI-MS spectra. Cytotoxic properties of target compounds were also studied by the MTT test on cell lines of human tumors (MCF-7, A549, PC-3, and HCT-116). Based on the SAR results, the resulting products can potentially be used as a new candidate drug for a promising anti-cancer strategy. [ABSTRACT FROM AUTHOR]