Lawsone and its derivatives have a variety of applications in the field of pharmaceutical research: as drug candidates, reagents for the chelation and recognition of metal cations (including those for catalytic applications), chemosensors for anions, and materials for energy storage applications. Moreover, there are some reports on the application of lawsone and its derivatives in the forensic science field. One of the most attractive features of lawsones is their bright color and well-pronounced fluorescence, which can be altered due to covalent or non-covalent interactions with various species. In this work, we endeavor to present our recent findings on the fluorescence response of lawsone and its methyl ester to nitro compounds and explosives components, such as 2,4-dinitrotoluene (DNT), 2,4,6-trinitrotoluene (TNT), 2,4,6-trinitrophenole (picric acid, PA), 2-nitromesitylene (2-NM), 4-nitrophenol (NP) as well as Fe3+ (FeCl3). In all the cases a dramatic fluorescence turn-off response was observed with up to 104 M-1 quenching constants. To explore the practical application of lawsone derivatives a mechanochemical modification of polyvinyl chloride (PVC) with lawsone residues was carried out, and thus obtained polymer was found to exhibit a pronounced fluorescence turn-off response to the both nitro-compounds and Fe3+ with as high as 104 M–1 quenching constants.

Carwash facilities generate considerable amounts of wastewater, which presents both an environmental challenge and a potential alternative water source. To facilitate reuse, this wastewater must meet stringent quality standards. In this study, three novel ultrafiltration (UF) membranes were developed for the first time to treat carwash wastewater (CWW). These membranes were fabricated from postmodified (PM) polyvinyl chloride (PVC) derivatives: PVC modified with 4-tert-octylthiophenol (PP1), 4-tert-butylthiophenol (PP2), and thiophenol (PP3) using a mechanosynthesis approach. The membranes were synthesized by incorporating the respective modified polymers into a solvent mixture of tetrahydrofuran (THF) and N-methyl-2-pyrrolidone (NMP) via the casting solution technique. Structural characterization was performed using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The membranes exhibited thicknesses of 143 mu m (PP1), 178 mu m (PP2), and 139 mu m (PP3), porosity ranging from 64.67% to 73.33%, and average pore sizes between 23.41 and 28.81 nm. Performance testing revealed that PP1 demonstrated the highest rejection rates for suspended solids (99%), oil products (82.4%), and surfactants (79%), with a flux of 40.24 L/m2 h. Although PP3 achieved the highest water flux (61.82 L/m2 h), its rejection performance was slightly lower. Retentate underwent biological treatment, removing 85%-90% of organic matter, supporting sustainable wastewater reuse.

The reaction of pyrazines with 2,5-norbornadiene, an acetylene precursor, as a cascade of Diels-Alder reactions is reported yielding substituted pyridines. In contrast to the known examples of intermolecular Diels-Alder type reaction of pyrazines with acetylene, which usually leads to a mixture of products, in our case the formation of a single isomer was observed. The proposed approach allows the conversion of pyrazines with different types of substitution, except those containing methyl and amino donor groups, to pyridines. In addition, highly functionalized aminonicotic esters were obtained, which can be used for the synthesis of bioactive compounds. An unusual course of the Diels-Alder reaction was found in the case of tetrasubstituted pyrazines, which cleave organic nitriles instead of HCN. Quantum-chemical modeling of possible transition states showed that this Diels-Alder reaction proceeds via cycloaddition of 2,5-norbornadiene to pyrazine with sequential elimination of HCN and cyclopentadiene; the reaction pathway including initial formation of acetylene from norbornadiene and subsequent Diels-Alder reaction with the acetylene was rejected as kinetically unfavorable.

Quinine Ester of Naproxen was obtained for the first time by O-acylation of quinine with naproxen [(S)-6-methoxy-α-methyl-2-naphthaleneacetic acid] chloride under alkaline conditions. The structure of the product was proved by 1H NMR. The photophysical properties of the resulting compound were studied, an intense fluorescent response to picric acid with a Stern–Volmer constant Ksv ≈ 1×106 M–1 was shown.

A series of 16 (hetero)aryl compounds based on coumarin and equol has been efficiently synthesized by exploring the palladium-catalyzed Suzuki cross-coupling reactions. Polyphenol based on coumarin (4-methyl-7-hydroxy coumarin) was initially converted to corresponding coumarin imidazylate and then subjected to Suzuki coupling reaction with 4-methoxyphenylboronic acid to obtain the coupled product. This modified approach was later developed into a one-pot methodology by directly reacting the polyphenol with 1,1-sulfonyldiimidazole (SDI) and boronic acid in situ to obtain the Suzuki coupled product in one step. Moreover, an array of (poly)phenols based on coumarin and equol were later converted to diverse (hetero)aryl compounds by this optimized step-economic protocol. The synthesized compounds were then subjected to the screening of their potential antioxidant activities by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. In our investigation, the compounds 4ah, 4eh, 4gh and 4hh exhibited promising antioxidant potential when compared to the reference standard, butylated hydroxytoluene (BHT). Structure activity relationship (SAR) studies revealed the importance of the presence of electron-donating substituents in enhancing the antioxidant activity of the synthesized compounds.

Tetraarylantimony(V) carboxylates based on 5-carboxyl and 6-carboxyl 2,2’-bipyridines (4 compounds) were synthesized for the first time. The structure of one of the compounds was confirmed by X-ray diffraction analysis. It was shown that the carboxyl group participates in the coordination of the antimony(V) cation, but the bipyridine fragment does not. The antitumor activity of the new complexes was assessed by molecular docking, and the most probable targets were determined. It was shown that the affinity of ligands to them is higher than that of the corresponding complexes. The best results were obtained for complex 3a; its inhibition of VEGFR2 is 74% more effective compared to the native ligand. In addition, the primary photophysical properties of the new carboxylates in acetonitrile solutions were studied. It was shown that the luminescence quantum yield values strongly depend on the position of the carboxyl group: for 5-substituted compounds they reach 65.0%, while for 6-substituted ones they have an extremely low ( 0.1%) value. At the same time, the absorption and emission maxima are within 300–314 nm and 364–403 nm, respectively.

The applicability of SNH and click reactions in the series of 2-amino-5-bromomethyl-3-(ethoxycarbonyl)pyrazine 1-oxide and its derivatives for the synthesis of distant analogs of folic acid and fluorophores was studied. The target products were synthesized in the yields up to 81

Polyvinyl chloride (PVC) plays an important role in industry; however, due to its uncontrolled accumulation in the environment, the methods for its utilization are of high demand. Herein we wish to report an approach for the utilization of PVC via its use as a carrier for some azole-based drugs, such as 2-mercaptobenzothiazole (multi-activity drug), 4-oxo-1,4-dihydropyrazolo[5,1-c]-1,2,4-triazine-3,8-dicarboxylic acid diethyl ester (antidiabetic drug) and 5-methyl-6-nitro-7-oxo-1,2,4-triazolo[1,5-a]pyrimidinide (antiviral drug). The abovementioned approach involves the reaction between PVC and potassium or sodium salts of these azole-based drugs either in solution or under ball-milling conditions. The as-obtained PVCs modified with azole-based drugs were isolated for the first time and characterized by means of 1H NMR-spectroscopy as well as gel-permeation chromatography (GPC).

Synthesis of nanofibrous carbon (multi-wall carbon nanotubes, MWCNTs) by means of n-hexane pyrolysis is reported. The structure of the obtained MWCNTs was studied using scanning electron microscopy, and the diameters of 20–85 nm and lengths of 500–600 nm for these nanotubes were observed. By using the above mentioned MWCNTs field-effect transistors were fabricated on ITO glass substrates with a gate dielectric made of 390 nm thick Al2O3 foil and the drain-source contacts made of 300 nm thick aluminum foil. The Nano-C film 200 nm thick was deposited by thermal evaporation in vacuum. The properties of the obtained field-effect transistors were studied. The current-voltage characteristics of the OFET show an increase in currents with a positive voltage on the gate, which corresponds to the electron conductivity of the transport channel. The dependences are nonlinear, and there are no saturation regions in the output characteristics. The Raman spectra indicate the presence of nickel and show characteristic peaks for C=C and CH bonds.

New 5-[4(3)-R-phenyl]-2,2′-bipyridines bearing the 1,1,7,7-tetrakis(tert-butoxycarbonylmethyl)-1,4,7-triazaheptane (DTTA) moiety at the C(6) position (R = Cl, Br, CF3) and their water-soluble EuIII complexes were synthesized. The photophysical properties of the synthesized complexes were investigated. More efficient sensitization of Eu3+ cation luminescence was demonstrated for a number of halogen-containing ligands. Some chelates exhibited moderate cell-staining ability. The synthesized compounds did not show significant photodynamic activity, which may be due to the inhibition of the in situ generation of reactive oxygen species via the supposed interaction with the methylene moiety of DTTA-appended 2,2′-bipyridine ligands.

Abstract—Ultrafine ZnO–ZnS powder with d-metal oxide additions, namely, V2O5, MnO, Fe2O3, CoO, NiO, and CuO are studied. The alloying of the ZnO–ZnS system with d metals changes the morphology of the synthesized powders. The particle size distribution obeys a lognormal law. An addition of d metal oxide upon the synthesis of ZnO–ZnS composite shifts the maximum of the particle-size distribution to the larger sizes. The more probable particle size in the samples alloyed with iron and cobalt (530 nm) exceeds that of unalloyed samples (320 nm) by more than 1.6 times. All the synthesized samples are found to be characterized by excess oxygen. The zinc, sulfur, and oxygen contents in the unalloyed ZnO–ZnS compositions is 48.0, 12.8, and 39.2 at

Discovered in 2008 by T.Ogoshi and co-workers, pillararenes have already attracted much attention due to their highly organized rigid structure and electron-rich cavity capable of accommodating various cationic and neutral guests. Pillararenes are successfully used in supramolecular tectons, liquid crystals, porous materials, organic–inorganic hybrid systems, drug delivery systems and, most importantly, in various metal-supported or metal-free catalytic systems. The current review highlights the most representative examples of the use of pillararenes for the catalytic applications. In particular, the metal-free pillararene-based catalytic systems for the Knoevenagel condensation reactions as well as supramolecular artificial enzymes and phase transfer catalysts will be analyzed. Among the metal-based catalysts the pillararene-supported catalysts for C–C-coupling reactions, including asymmetric or cycloaddition reactions, as well as pillararene-supported nanoparticles or polyoxometalates will be analyzed. Special attention will be paid to pillararene-mediated photocatalytic reactions. The bibliography includes 151 references.

Iptycenes are common building blocks for the small-molecules or polymer-based chemosensors and fluorophores. In addition, iptycene derivatives are widely presented in polymers of intrinsic microporosity (PIMs) as materials for the separation and purification technologies. In this manuscript we wish to report a mechanochemical approach to pentiptycene-based polyesters and polycarbonates as, possibly, new representatives of PIMs. Our approach involves the polycondensation reaction between 5,7,12,14-tetrahydro-5,14:7,12-bis([1,2]benzeno)pentacene-6,13-diol (pentiptycene-6,13-diol) and triphosgene or oxalyl chloride under ball-milling conditions. The obtained polymers were characterized by means of 1H NMR- and IR-spectroscopy. As the last step, the fluorescence “turn-off” response of pentiptycene-6,13-diol and two pentiptycene-based polymers towards nitroanalytes (2,4-dinitrotioluene (DNT) and 2,4,6-trinitrophenole (picric acid, PA)) was investigated, and Stern-Volmer constants as high as 1o4 M–1 were observed.

A series of novel iridium(III) complexes containing 5-N-(aryl)-amino- or 5-cycloamino-3-(pyridine-2-yl)-1,2,4-triazine ligands was obtained. These complexes exhibited red luminescence in solution as well as in the solid state. Based on the DFT studies it was suggested that N(2) atom of the 1,2,4-triazine core is preferable to N(4) one as the coordination site in the complexes of Ir(III).

A convenient synthetic approach to 2-(2,2'-bipyridin-6-yl)-1,3,4-oxadiazole derivatives is proposed, which involves the preparation of 5-aryl-2,2'-bipyridine-6-carboxylic acid esters by the “1,2,4-triazine” methodology and the subsequent construction of the 1,3,4-oxadiazole ring via the modification of the ester group.

Cyanide ions are known to be lethal for insects and mammals and harmful for the environment, and new methods for their selective detection are in high demand. Herein, the mechanosynthesis of simple Schiff’s bases-based probes S1–S3 for visual detection of CN− anion is reported. These probes were obtained by means of a reaction between isomeric 4,4-, 3,3- and 2,2-diaminobiphenyls and 4-nitrobenzaldehyde under ball milling conditions. The probes showed high selectivity and sensitivity toward CN− anion via a dramatic “yellow-to-dark purple” color change with a detection limit of 26 × 103, 8.7 × 103 and 14 × 103 ppm for S1–S3, respectively. The proposed mechanism of the detection suggests the deprotonation of a proton from an imine moiety, followed by the formation of charge transfer complexes (CTC).

A convenient synthetic approach to derivatives of 2-(2,2ʹ-bipyridin-6-yl)-1,3,4-oxadiazoles is proposed as a result of the preparation using the “1,2,4-triazine” methodology of esters of 5-aryl-2,2ʹ-bipyridine-6-carboxylic acids and the subsequent construction of the 1,3,4-oxadiazole cycle by to modification of the ester group.

The reactions of isoxazol-3-amine, thiazol-2-amine, benzo[d]thiazol-2-amine with 4-nitrobenzaldehyde and indole in the absence of a solvent under ball-milling conditions were studied. The reactions proceed through the in situ formation of a Schiff base and subsequent nucleophilic addition of indole at the C=N fragment to form the addition products, α,α-disubstituted azolyl-amines, in yields up to 80

An attempt to obtain 2-ethynylnaphthalene from 2-(1-chloroethenyl)naphthalene in a glass reactor containing traces of palladium black on the inner wall surface resulted in the formation of homo- and cross-coupling products which were identified by GC/MS.

Mechanochemically induced methods are commonly used for the depolymerization of polymers, including plastic and agricultural wastes. So far, these methods have rarely been used for polymer synthesis. Compared to conventional polymerization in solutions, mechanochemical polymerization offers numerous advantages such as less or no solvent consumption, the accessibility of novel structures, the inclusion of co-polymers and post-modified polymers, and, most importantly, the avoidance of problems posed by low monomer/oligomer solubility and fast precipitation during polymerization. Consequently, the development of new functional polymers and materials, including those based on mechanochemically synthesized polymers, has drawn much interest, particularly from the perspective of green chemistry. In this review, we tried to highlight the most representative examples of transition-metal (TM)-free and TM-catalyzed mechanosynthesis of some functional polymers, such as semiconductive polymers, porous polymeric materials, sensory materials, materials for photovoltaics, etc.