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Based on esters of nicotinic and isonicotinic acids with hydroxybenzaldehydes, a series of functionally substituted derivatives containing isoxazole and isothiazole heterocycles in the molecule have been synthesized. Azomethines were obtained by condensation of nicotinates and isonicotinates with p-bromoaniline and m-aminophenol, which have been reduced with sodium triacetoxyborohydride to give the corresponding amines. Acylation of amino derivatives of nicotinates and isonicotinates with 5-arylisoxazole- and 4,5-dichloroisothiazolecarbonyl chlorides leads to the esters and amides with isoxazole and isothiazole residues.

2-Mercapto-1,3,4-triazoles and 2-amino-1,3,4-thiadiazoles were synthesized by successive transformations of 5-arylisoxazole- and 4,5-dichloroisothiazole-3-carboxylic acids and their derivatives. The amino group of 5-(4,5-dichloroisothiazol-3-yl)-1,3,4-thiadiazol-2-amine was acylated with 5-phenylisoxazole-3-carboxylic acid chloride. Simple approaches to the preparation of previously unknown heterocyclic assemblies containing two or three azole rings with a high potential for biological activity are described.

A convenient one-pot approach was proposed for the synthesis of new derivatives of 8,9,10,12tetrahydrobenzo[a]acridin-11(7H)-one and 10,12-dihydrobenzo[f]pyrimido[4,5-b]quinoline-9,11(7H,8H)-dione containing residues of nicotinic and isonicotinic acids covalently attached via ester groups in different positions of the aromatic core. Quaternary ammonium salts of the synthesized acridine derivatives as well as a metal complex with palladium PdLCl2 were obtained. These compounds contain a number of pharmacophore groups so going to be promising potential drugs with antimicrobial, antiviral, and antitumor activity.

The reaction of 4-substituted anilines with 3,4,4-trichloro-1,1-bis(3,5-dimethyl-1H-pyrazol-1-yl)-2-nitrobuta-1,3-dienes led to 1-arylamino-3,4,4-trichloro-1-(3,5-dimethyl-1H-pyrazol-1-yl)-2-nitrobuta-1,3-dienes, which under the action of 2-aminopyridines underwent heterocyclization to the corresponding 2-arylamino-substituted 4-(dichloromethylidene)-3-nitro-4H-pyrido[1,2-a]pyrimidines. The molecular structure of 4H-pyrido[1,2-a]pyrimidine containing the (4-ethoxyphenyl)amine substituent at position 2 was determined by X-ray structural analysis.

A convenient and scalable preparative method for the synthesis of azomethines from 4-amino-1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one and substituted benzaldehydes, as well as 1,2-oxazole and 1,2-thiazolecarbaldehyde was developed.

We report for the first time cyclic phosphine-free "head to tail" N,N,N pincer-like (pincer complexes mimicking) N-(pyrimidin-2-yl)-1,2-azole-3-carboxamide Pd(II) complexes with deprotonated amide groups as high-turnover catalysts (TON up to 106, TOF up to 1.2 × 107 h-1) for cross-coupling reactions on the background of up to quantitative yields under Green Chemistry conditions. The potency of the described catalyst family representatives was demonstrated in Suzuki-Miyaura, Mizoroki-Heck, and Sonogashira reactions on industrially practical examples. Corresponding ligands could be synthesized based on readily available reagents through simple chemical transformations. Within the complex structures, a highly unusual 1,3,5,7-tetraza-2,6-dipalladocane frame could be observed.

Curcumin is a chemical compound with antioxidant properties as well as strong anti-inflammatory, antiviral, analgesic, antimicrobial and antitumor effect, contained in the tuberous rhizomes of the turmeric plant (Curcuma longa). Curcumin derivatives are being intensively studied as potential drugs – antitumor drugs for the treatment of certain forms of cancer. The presence of reactive functional groups makes curcumin a convenient starting compound for the further chemical modification. The esters of curcumin and 5-phenylisoxazole-3-carboxylic acid, 5-(p-tolyl)isoxazole-3-carboxylic acid, 4,5- dichloroisothiazole-3-carboxylic acid and adduct of 5-(p-tolyl)isoxazol-3-carbaldehyde with curcumin were synthesized. Esters were obtained by acylation of curcumin with heterocycle-containing carboxylic acid chloride in diethyl ether in the presence of triethylamine. The IR and NMR spectra of the obtained compounds are described.

The oxidation of 1,2-C2B10H12 (1) with 100% nitric acid was studied in two solvents (CH2C12 and CCl4). Under the action of superacid (CF3SO3H), the compound 9-HO-1,2-C2B10H11 (2) gives the onium cation 9-H2O+-1,2-C2B10H11 involved in the salt [9-H2O+-1,2-C2B10Hn]-CF3SO3−, as demonstrated by uB NMR spectroscopy. The experimental and simulated uB NMR spectra of the cation 9-H2O+-1,2-C2B10H11 are in satisfactory agreement with each other. In the presence of a base, compound 2 is transferred from an ethereal solution to an aqueous alkaline solution giving the anion 9-O−- 1,2-C2B10H11. The structure of compound 2 was confirmed by 1H, 11B, 11B1H, 11B-11B COSY NMR spectroscopy, IR spectroscopy, and gas chromatography mass spectrometry and was additionally established by X-ray diffraction.

The reaction of 3,4,4-trichloro-1,1-bis(3,5-dimethyl-1H-pyrazol-1-yl)-2-nitrobuta-1,3-diene with 2-aminopyridine gave a polysubstituted pyrido[1,2-a]pyrimidine derivative with an aminopyridine residue in the 2-position, whereas heterocyclization of 3,4,4-trichloro-1,1-bis(1H-benzotriazol-1-yl)-2-nitrobuta-1,3-diene with substituted 2-aminopyridines afforded 2-(1H-berrzotriazol-1-yl)pyrido[1,2-a]pyrimidines. 2-(Morpholin-4-yl), 2-amino, and 2-(2-hydroxyethylamino) derivatives of polysubstituted pyrido[1,2-a]pyrimidines were synthesized, and those containing a 2-hydroxyethylamino group were converted to the corresponding 4,5-dichloro-1,2-thiazole-1-carboxylates. Specific features of heterocyclizations of benzotriazolyl and dimethylpyrazolyl derivatives of trichloronitro-1,3-butadiene to pyrimidine and pyrazole systems were revealed.

The chemistry of isothiazoles is being intensively developed, which is evidenced by the wide range of selective transformations involving the isothiazole heterocycle and the high biological activity of its derivatives that can be used as effective new drugs and plant protection chemicals. Some representatives of isothiazoles have proven to be synergists of bioactive substances, which opens the way to lower the doses of drugs used and is especially important in cancer chemotherapy. In the framework of the present review, the accomplishments in the chemistry of isothiazoles over the past 18 years are examined, whilst current strategies for the synthesis of isothiazole-containing molecules and key directions of studies in this field of heterocyclic chemistry are discussed. Considerable attention is paid to chlorinated isothiazoles and strategies for their use in the synthesis of biologically active substances. In addition, a comprehensive review of existing literature in the field of metal complexes of isothiazoles is given, including the results and prospects for the practical use of isothiazole–metal complexes as catalysts for cross-coupling reactions in aqueous and aqueous–alcoholic media (‘green chemistry’).1 Introduction2 Synthesis by Ring-Forming Reactions2.1 Intramolecular Cyclization2.2 (4+1)-Heterocyclization2.3 (3+2)-Heterocyclization2.4 Syntheses by Ring Transformations3 Isothiazoles by Ring Functionalization Reactions: Nucleophilic Substitution, Cross-Coupling and Side-Chain Functionalization4 Selected Syntheses of Biologically Active Isothiazole Derivatives5 Isothiazoles in the Synthesis of Transition-Metal Complexes and in Metal-Complex Catalysis6 Conclusion

Deboration of 1-PhCH2-1,2-C2B10H11 by heating in ethanolic potassium hydroxide afforded Me4N+ [7-PhCH2-7,8-C2B9H11]− which was treated with excess halosuccinimide (NCS, NBS) in acetonitrile or with elemental iodine or bromine in methanol to obtain Me4N+ [7-PhCH2-9,11-X2-7,8-C2B9H9]− (X = Cl, Br, I). The reaction of 1-PhCH2-1,2-C2B10H11 with an equimolar amount of iodine gave a mixture of Me4N+·[7-PhCH2-11-I-7,8-C2B9H10]- and Me4N+[7-C6H5CH2-9-I-7,8-C2B9H10]− at a ratio 1:1.8 due to steric effect of the benzyl substituent. The 11B chemical shifts of each μ-H tautomer of Me4N+ [7-PhCH2-9,11-X2-7,8-C2B9H9]− (X = H, F, Cl, Br, I) were calculated at the DFT level of theory, and their contributions to the average 11B NMR spectrum and the corresponding tautomeric equilibrium constants were determined.

Acylation of vanillin with isonicotinoyl chloride gave 4-formyl-2-methoxyphenyl pyridine-4-carboxylate which was converted into a number of functional derivatives, including those containing isoxazole and isothiazole heterocycles. In particular, the condensation of the title compound with primary amines afforded the corresponding Schiff bases. 4-Formyl-2-methoxyphenyl pyridine-4-carboxylate and one of the Schiff bases derived therefrom were reduced with sodium triacetoxohydridoborate to the corresponding alcohol and amine which were acylated with 5-arylisoxazole- and 4,5-dichloroisothiazole-3-carbonyl chlorides to obtain esters and amides having isoxazole and isothiazole fragments. The synthesized compounds readily formed complexes with palladium(II) chloride, which showed a high catalytic activity in the Suzuki reaction of 3-bromobenzoic acid with 4-methoxyphenylboronic acid in water in the absence of an organic solvent.

It was found that the reaction of 5-arylfurfurilamines with maleic anhydride leads to the formation of 6-aryl-3a,6-epoxyisoindole-7-carboxylic acids (the cyclic form), which in solution are in dynamic equilibrium with N-furfurylmaleinamides (the open form). During the esterification of these tautomeric mixtures with methanol in the presence of a catalytic amount of sulfuric acid, methyl esters of 5-aryl-7a-hydroxy-7-methoxy-3-oxo-2,3,3a,4,7,7a-hexahydro-1H-isoindole-4-carboxylic acids, unexpected cleavage products of the 3a,6-oxo bridge of the cyclic form, are formed diastereospecifically. The structure of the obtained products was confirmed by X-ray structural analysis.

Three-component cascade cyclocondensation of naphthalen-2-amine with cyclic β-dicarbonyl compounds and isoxazole- or isothiazolecarbaldehydes afforded new structural analogs of alkaloids containing isoxazole and isothiazole fragments.

In this work, 1,4-dioxane-mediated hydroxylhydrative aza-cyclization of 2-alkynylbenzamide is developed for the synthesis of 3-hydroxylisoindolin-1-ones. The transformation proceeds smoothly in water with good yields and a broad reaction scope. Mechanistic studies show that regioselective brimonative 5-exo-dig aza-cyclization, bromohydration of the resulting alkene groups, and hydrolysis of dibromo compounds are involved. Compared to the traditional methodologies, the synthetic procedure reported herein represents a cleaner route toward 3-hydroxylisoindolin-1-ones.

By acylation of substituted 2-aminoarylpyrimidines with 5-phenyl(p-tolyl)isoxazole- and 4,5-dichloroisothiazole-3-carbonyl chlorides new amides of pyrimidine series were obtained.

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.

Acylation of hydroxyl-containing heterocyclic compounds with 1,1'-ferrocenedicarbonyl chloride afforded diheteryl-1,1'-ferrocenedicarboxylates. Bisaldehyde-containing diesters were obtained by acylation of hydroxybenzaldehydes. The condensation of the latter with 2-naphthylamine or 4-phenylazoaniline resulted in the formation of the corresponding azomethines. The reduction of bisaldehyde-containing diesters furnished ferrocene-containing diols. Ferrocene tetrahydrobenzo[a]acridine-11-(7H)-one derivatives were synthesized as a result of the three-component cascade heterocyclization of ferrocene bisaldehyde-containing diesters with 2-naphthylamine and dimedone.

The reduction of acetylcymantrene with sodium tetrahydridoborate gave cymantrenylethanol which was acylated with 4,5-dichloroisothiazole- and 5-(4-methylphenyl)isoxazole-3-carbonyl chlorides to obtain esters containing a 1,2-thia(oxa)zole fragment. The condensation of acetylcymantrene with 5-arylisoxazole-3- carbaldehydes, (5-arylisoxazol-3-yl)methoxybenzaldehydes (Ar = Ph, 4-Tol), and 4,5-dichloroisothiazole-3- carbaldehyde afforded the corresponding (E)-3-(azol-3-yl)-1-cymantrenylprop-2-en-1-ones. The resulting α,β- unsaturated ketones reacted with semicarbazide hydrochloride and thiosemicarbazide to produce substituted 4,5-dihydro-1H-pyrazole-1-carboxamides and -1-carbothioamides, and their reaction with hydroxylamine hydrochloride led to the formation of 4,5-dihydroisoxazoles containing cymantrene and 1,2-azole fragments. Heterocyclization of azolylcymantrenylpropenones with guanidine gave 2-aminopyrimidine derivatives, and dihydropyrimidine-2-thiones were obtained by their reaction with thiourea.

Alkylation of fluorophenols and phenolic aldehydes with 5-phenyl(p-tolyl)-3-chloromethylisoxazole under the Williamson reaction conditions afforded the corresponding ethers. Condensation of the resulting phenolic aldehyde derivatives and 5-phenyl(p-tolyl)isoxazole-3-carbaldehydes with p-fluoroaniline resulted in fluorine-containing azomethines. Acylation of fluorinated amines with 5-(p-tolyl)isoxazole- and 4,5- dichloroisothiazole-3-carbonyl chlorides gave rise to fluorinated amides bearing isoxazole and isothiazole fragments, representatives of which showed a synergistic effect in compositions with insecticides.

The condensation of ethyl 4-(chloromethyl)-2,6-dimethylpyridine-3-carboxylate with substituted phenols in ethanol in the presence of potassium carbonate afforded the corresponding aryl pyridin-4-ylmethyl ethers. Analogous condensation with substituted anilines gave 2-aryl-4,6-dimethyl-1,2-dihydropyrrolo[3,4-c]- pyridin-3-ones. Esters containing 1,2-azole fragments were synthesized by acylation of hydroxymethylsubstituted ethers with 5-arylisoxazole- and 4,5-dichloroisothiazole-3-carbonyl chlorides.

A reaction sequence involving transformations of 5-(4-methylphenyl)isoxazole and 4,5-dichloroisothiazole derivatives containing an amidoxime group at position 3 allowed to synthesize the respective 3,5-isoxazolyl(isothiazolyl)-substituted 1,2,4-oxadiazoles. Selective recyclization of 4,5-dichloro-3-(1Н-tetrazol-5-yl)isothiazole and 5-(4-methylphenyl)-3-(1Н-tetrazol-5-yl)isoxazole gave 2,5-isoxazolyl-(isothiazolyl)-substituted 1,3,4-oxadiazoles. The obtained compounds combining three azole heterocycles in one molecule formed palladium complexes that showed high catalytic activity in Suzuki reactions in aqueous and aqueous alcohol media. The bimetallic reusable Pd/Fe catalyst obtained from palladium polyazole complex retained high catalytic activity after five uses.

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.

Conjugates of ferrocene and 4,5-dichloroisothiazole were synthesized, where the ferrocene and isothiazole moieties are linked through various structural fragments. The acylation of ferrocene with 4,5- dichloroisothiazole-3-carbonyl chloride gave (4,5-dichloroisothiazol-3-yl) ferrocenyl ketone; the acylation of aminomethylferrocene furnished the corresponding amide. The esterification of ferrocene-1,1′-dicarboxylic acid with 4,5-dichloroisothiazol-3-yl-methanol resulted in the formation of the corresponding ester. The condensation of 1,1′-diacetylferrocene with 4,5-dichloroisothiazole-3-carbaldehyde afforded ferrocenophane containing 4,5-dichloroisothiazole moieties.

Condensation of acetylferrocene with 5-phenyl(4-methylphenyl)-1,2-oxazole-3-carbaldehydes afforded (Е)-3-[5-phenyl(4-methylphenyl)-1,2-oxazol-3-yl]-1-ferrocenylprop-2-en-1-ones. Reactions of (Е)-3-[5-(4-methylphenyl)-1,2-oxazol-3-yl]-1-ferrocenylprop-2-en-1-one with semicarbazide, thiosemicarbazide, and hydroxylamine led to the formation of 5-[5-(4-methylphenyl)-1,2-oxazol-3-yl]-3-ferrocenyl-4,5-dihydro-1H-pyrazole- 1-carboxamide, 5-[5-(4-methylphenyl)-1,2-oxazol-3-yl]-3-ferrocenyl-4,5-dihydro-1H-pyrazole-1-carbothioamide, and 5-(4-methylphenyl)-3'-ferrocenyl-4',5'-dihydro-3,5'-bi-1,2-oxazole respectively. Reactions of (Е)-3-[5-(4-methylphenyl)-1,2-oxazol-3-yl]-1-ferrocenylprop-2-en-1-one with guanidine and thiourea result in 4-[5-(4-methyl-phenyl)-1,2-oxazol-3-yl]-6-ferrocenylpyrimidin-2-amine and -2-thione respectively.

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.

From (4,5-dichloroisothiazol-3-yl)phenylmethanol by Ritter reaction a substituted acetamide was synthesized that at hydrolysis with HCl afforded (4,5-dichloroisothiazol-3-yl)phenylmethylamine hydrochloride. By reaction of (5-arylisoxazol-3-yl)- and 4,5-dichloroisothiazol-3-yl)arylmethanol with thionyl chloride the corresponding (1,2-azol-3-yl)arylchloromethanes were obtained. At treatment with O- and N-nucleophiles chlorine atom in chloromethylеne fragment of obtained compounds was substituted by residues of benzylamine, morpholine, vanillin, and ethoxy group.

2-Amino-4-R-6H-1,3-thiazine-6-thiones and 2-amino-4-phenyl-6H-1,3-thiazin-6-one react with highly electrophilic N-arylsulfonylimines of chloral and phenyldichloroacetic aldehyde at the exocyclic amino group affording in good yields products of nucleophilic addition to the azomethine group of imines: N-[2-polychloro-1-(6-thioxo-4-R-6H-1,3-thiazin-2-ylamino)ethyl]- or -[2-polychloro-1-(6-oxo-4-phenyl-6H-1,3-thiazin-2-ylamino)ethyl]arenesulfonamides.

Condensation of aromatic, isoxazole, and ferrocene aldehydes as well as 1,1’-diacetylferrocene with 5-(4-methylphenyl)isoxazole-3-carbohydrazonamide afforded various N-substituted azines with molecular fragments of the corresponding aldehydes or diacetylferrocene.

Acylation of alkyl- and 1,1′-dialkylferrocene alcohols and diols as well as (3,4,4-trichlorobut-3-ene-1-ol-1-yl)-4,5-cymantrene with dichloroisothiazole- and 5-arylisoxazole-3-carbonyl chlorides has afforded esters containing 1,2-azoles fragments. Some of the obtained compounds have exhibited potentiating action in the binary mixtures with insecticides.

Homogenous and heterogeneous palladium catalysts with functionalized izoxazole and isothiazole ligands were developed for the cross-coupling reactions. The catalysts possessed high activity and were suitable for the repeated use. Compared with commonly used organic solutions, application of water and its mixtures with methanol as a reaction medium significantly intensifies catalysis with no side being formed. The obtained results are promising for the development of effective and ecologically friendly technologies of synthesis of important compounds such as polyfunctional biaryls, arylated olefins, acetylenes and their heterocyclic analogs.

Functionally substituted 5-(p-tolyl)isoxazoles and 4,5-dichloroisothiazoles, whose molecules contain azomethine, amino, carboxyl, and ester moieties in various combinations in the aromatic ring in the position 3 of heterocycle, were synthesized. Synthesis of complexes of Pd(II) with carboxyl derivative of 1,2-azoles was performed. They show high catalytic activity in the Suzuki reaction in aqueous media.

DFT simulations of the electron and spin structure of fullerenol derivatives C60(OH)24·2Fe(C5H4COOH)2 and C60(OH)24·2Ni(C5H4COOH)2 have shown that these compounds form stable complexes with intermolecular hydrogen bonds. Calculated exchange coupling constants for the last complexes indicate that they can possess ferromagnetic properties. If this is true, then compounds will have a great potential for medical application as drug delivers under the control of external magnetic field.

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.

Structure and energy calculations of modified complexes of single-walled carbon nanotubes and fullerenol C[Formula: see text](OH)[Formula: see text] with cisplatin have been performed using the quantum chemical method at the DFT/B3LYP/SV/Lanl2DZ level. The nanotubes were modified with COOH groups at the end and sidewall of the nanotube and cisplatin molecules. The dependence of their structure on the presence of a solvent was established.

Methyl 5-hydroxy-4-oxo-4 H-pyran-2-carboxylate was synthesized by esterification of methanol with comenic acid under acidic catalysis. The obtained ester was alkylated with 3-(chloromethyl)-5-phenylisoxazole and 4,5-dichloro-3-(chloromethyl)isothiazole to afford corresponding conjugates containing isoxazole and isothiazole moieties which then were transformed into water-soluble Li-salts. During the bioassays of synthesized isoxazole and isothiazole derivatives of comenic acid in mixtures with first-line antitumor drug Temobel (Temozolomid) used in brain tumors chemotherapy, a synergetic effect was observed.

By alkylation of vanillin with 4,5-dichloro-3-chloromethylisothiazole the corresponding ether was synthesized. The latter was then reacted with p-toluidine to afford the corresponding azomethine. During the bioassays of synthesized isothiazolic derivatives of vanillin in mixtures with insecticides (imidacloprid and α-cypermethrin) a strong synergetic effect was observed.