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New substituted 3-((1H-1,2,3-triazol-1-yl)methyl)-5-arylisoxazoles (aryl = Ph, p-Tol) and 2-(5-phenylisoxazol-3-yl)-5-(2-(1-((5-(p-tolyl)isoxazol-3-yl)methyl)-1H-1,2,3-triazol-4-yl)ethyl)-1,3,4-oxadiazole were synthesized by means of click-chemistry procedures. The obtained compounds were used as ligands in preparation of palladium(II) complexes, and the latter proved to be high-turnover-number catalysts for C C cross-coupling reactions under Green Chemistry conditions. One of the ligands was structurally characterized by single crystal X-ray diffraction, and the structure of complexes was determined by 1H, 13C, 15N NMR spectroscopy and quantum-chemical modeling.

Crystallization of Cu(NO3)2 with L = 3-(hydroxyiminomethyl)-5-(2,5-dimethylphenyl)isoxazole in conc. HNO3 affords [Cu2(NO2–L’)2(μ–H2O)2(H2O)2(NO3)2].2H2O, where the C-nitration of the exocyclic fragment and the formation of a dinuclear compound is observed. The ligands have two coordination positions (isoxazole nitrogen and one oxime nitrogen) and act as chelate ligands.

In the present work, the quantum chemical calculations of the molecular structures of the two newly synthesized dichroic dyes: 2-methoxy-4-((1E)-((4-(phenyldiazenyl)phenyl)imino)methyl)phenyl isonicotinate (IN-1); 2-methoxy-5-((1E)-((4-(phenyldiazenyl)phenyl)imino)methyl)phenyl isonicotinate (IN-2) have been predicted using Density Functional Theory (DFT) in solvent dimethylformamide (DMF). The geometries of the dichroic dyes were optimized using the B3LYP/6-311+G* level of the theory. In addition, the electronic spectra of these compounds in solvent DMF were carried out using the same method. After quantum-chemical calculations dichroic dyes for optoelectronic applications were synthesized. Based on polyvinyl alcohol (PVA) and the new synthesized azomethine dyes polarizing films for UV/Vis regions of the spectrum were developed. The main optical parameters of polarizing PVA-films (Transmittance and Polarization Efficiency) have been measured and discussed.

Despite the significant role of ciclopirox as a novel anticancer agent to treat various cancers such as breast, liver, colorectal and bladder, it has some adverse effects and poor solubility in water. Hence, the enhancement of ciclopirox polarity is crucial in biological systems. In this work, the effect of selenium decoration on the interaction of ciclopirox drug molecule with B12N12 was investigated using density functional theory (DFT) calculations. Based on structural analysis, C O group of ciclopirox was chemisorbed on the boron and selenium atoms of B12N12 and Se-B12N12 nanoclusters, respectively. It was found that the selenium decoration significantly improves the reactivity of B12N12 toward ciclopirox. A short recovery time (~2.13 s) was predicted for ciclopirox desorption from the Se-B12N12 nanocluster surface. The vibrational frequency analysis was conducted to survey the vibration frequencies of bonds formed in the CPX/nanocluster complex. The charge transfer process was studied using charge decomposition analysis (CDA). Furthermore, Quantum theory of atoms in molecules (QTAIM) analysis revealed that the non-covalent interactions between CPX and nanoclusters are essential for the delivery process. Finally, electronic properties analysis showed that energy band gap of Se-B12N12 nanocluster is significantly reduced from 0.2835 to 0.2121 a.u after ciclopirox adsorption.

A library of 4′-chloro- and 4′-fluorosulfonyl-substituted chalcones was prepared via the aldol-type condensation reactions of 4-acetylbenzene-1-sulfonyl halides with various aromatic aldehydes, either in absolute ethanol or glacial acetic acid, in the presence of dry HCl. This represents the first examples of chalcone sulfonyl halides in which the phenone ring bears one of these functional groups. The reactivity of the chalcone sulfonyl halides were strongly dependent on the styrene ring substituents; sulfonyl chlorides reacted with most nucleophiles (e.g. amines, alcohols), while sulfonyl fluorides reacted only with charged nucleophiles (e.g. phenolates).

N-Furfuryl allylamines, readily accessible from corresponding furfurals or furfuryl amines, react with a broad range of arylsulfonyl chlorides with the formation of a 3a,6-epoxyisoindole core in one synthetic stage. Usually, in boiling water, the interaction sequence involves two consecutive steps: the Hinsberg reaction and the intramolecular Diels–Alder furanе (IMDAF) reaction. The scope and limitations of the proposed method were thoroughly investigated, and it was revealed that the key [4 + 2] cycloaddition step proceeds through an exo-transition state, giving rise to the exclusive formation of a single diastereomer of the target heterocycle. The method allows the ability to obtain N-sulfaryl-substituted 3a,6-epoxyisoindoles and 4a,7-epoxyisoquinolines, which are potentially useful substrates for further transformations and subsequent bioscreening, in particular antimicrobial activity.

A series of 14 macromolecular derivatives of resorcinarenes and thiacalix[4]arenes bearing alkyl chains (up to -C11H23) and different photoreactive groups (chalcone sulfonyl, naphthyl (Np), alkyl azide (Alk-N3)) was synthesized. The obtained compounds were used to design monomolecular 2D films by the Langmuir-Blodgett method at the air/water interface using ultraviolet-assisted covalent crosslinking. It was found that the alkyl azide derivatives can effectively form cross-copolymerized two-dimensional films with the thickness of 0.8-1.5 nm, which was revealed with the help of atomic force topography. A controversial effect of UV irradiation on the film topography, namely, ordering and disordering of the film structure, was observed. The effect of donor and acceptor substituents in styrene ring of chalcone sulfonyl (carbonyl) chlorides on the wetting angle of the films and its dependence on concentration of voids in a coating, were also studied. It was found that the most ordered 2D structures are formed for compounds with a sterically balanced set of substituents.

Mixed-ligand copper(II) complexes based on 1,10-phenanthroline and related compounds are of interest to scientists due to their promising anticancer properties. In this study, four new water-soluble copper(II) complexes [Cu(dmbipy)L2], [Cu(phen)(H2O)L2], [Cu(dmphen)L2] and [Cu2(bipy)2L4], where HL – 4,5-dichloro-isothiazole-3-carboxylic acid, bipy – 2,2′-bipyridine, dmbipy – 2,2′-bi-4-picoline, phen – 1,10-phenanthroline, dmphen – 4,7-dimethyl-1,10-phenanthroline are reported. All complexes have been characterized by elemental and powder X-ray diffraction analysis, EPR and IR-spectroscopy. Molecular structures of the reported complexes have been determined by single crystal X–ray diffraction. Copper(II) ion, HL and heterocyclic N-donor ligands have been found to form 1:2:1 complexes that possess square bipyramid or square pyramidal geometry. The UV–vis spectroscopy and mass spectrometry have been applied to show the behavior of the compounds in solution. All complexes have been screened in vitro for their cytotoxic activity against Hep-2 and MCF-7 cell lines. They exhibit significant dose-dependent cytotoxic effect and [Cu(dmphen)L2] is found to be the most cytotoxic (IC50 = 0.97 ± 0.03 µM when compared to IC50 = 9.2 ± 0.5 µM for control, cisplatin – Hep-2 cell line). The investigation of DNA binding ability by UV–vis titration technique indicates that complexes obtained exhibit moderate binding affinity toward calf thymus DNA. Effect of [Cu(dmbipy)L2] and [Cu(dmphen)L2] on activity of drug-metabolizing enzymes cytochromes P450 has also been investigated. The addition of complexes to the hepatic microsomes of 3-MC or PB-treated rat, lead to a dose-dependent decrease of CYP’s activities. The data obtained indicate that [Cu(dmphen)L2] and [Cu(phen)(H2O)L2] can be potential anticancer agents.

Halogenation of 9-dimethylsulfonium-7,8-dicarba-nido-undecaborane [9-SMe2-7,8-C2B9H11] with N-chlorosuccinimide, bromine and iodine gave the expected corresponding halogen derivatives [9-SMe2-11-X-7,8-C2B9H10], where X = Cl (1), Br (2), I (3). In the bromination reaction, [9-SMe2-6-Br-7,8-C2B9H10] (4) was isolated as a minor product being the first example of substitution at a “lower” belt of the 7,8-dicarba-nido-undecaborate cage. The use of excess of bromine resulted in dibromo derivative [9-SMe2-6,11-Br2-7,8-C2B9H9] (5). Structures of the compounds prepared were determined using 11B–11B COSY NMR spectroscopy (for all halogen derivatives) and single crystal X-ray diffraction (for compounds 2, 3, and 5).