Vol 93, No 3 (2023)

Arylmethylenebis(3-hydroxy-2-cyclohexen-1-ones) were obtained by condensation of 1,2-azole- and pyridine-substituted aromatic aldehydes of the vanillin series with 1,3-cyclohexanedione in methanol in the presence of trimethylamine. Catalytic cyclization using fibrous sulfocationite FIBAN K-1 gave corresponding 1,8-dioxooctahydroxanthenes.

Condensation of 2-thioxo-2,3-dihydro-1 H -spiro[benzo[ h ]quinazoline-5,1′-cycloheptane]-4(6 H )-one with hydrazine hydrate afforded 2-hydrazinyl-3 H -spiro[benzo[ h ]quinazoline-5,1′-cycloheptane]-4(6 H )-one. The reaction of the latter with orthoformic acid ethyl ester or carbon disulfide yielded 5 H -spiro[benzo[ h ][1,2,4]triazolo[3,4- b ]quinazoline-6,1′-cycloheptane]-7(11 H )-one and 9-mercapto-5 H -spiro[benzo[ h ][1,2,4]triazolo[3,4- b ] quinazoline-6,1 ‘-cycloheptane]-7(11 H )-one, respectively. Alkylation of the latter with methyl and ethyl iodides, allyl bromide, and benzyl chloride gave 9-sulfanyl-substituted 5 H -spiro[benzo[ h ][1,2,4]triazolo[3,4- b ]quinazoline-6,1′-cycloheptane]-7(11 H )-ones. The synthesized compounds exhibited antibacterial properties.

The reactions of 5-(1,2-dicarbadodecaboran-1-yl)-3-(2-pyridyl)-1,2,4-triazines with various dienophiles (2,5-norbornadiene, 1-morpholinocyclopentene, 1,2-dehydrobenzene, and 2-amino-4-phenyloxazole) were studied. It was shown that the presence of a carborane fragment in the 1,2,4-triazine ring causes an atypical reaction with dienophiles without the formation of the expected aza -Diels-Alder reaction products except for the reaction with 2,5-norbornadiene. The reaction of 5-(1,2-dicarbadodecaboran-1-yl)-3-(2-pyridyl)-1,2,4triazines with 2-amino-4-phenyloxazole unexpectedly led to the formation of the corresponding 4,5-dihydro1,2,4-triazines. One of the previously described procedures for the direct introduction of a carborane residue into the C⁵ position of 1,2,4-triazines was optimized.

Methods of synthesis of phosphonomethylated acetoxymethyl derivatives of acetylfurans and alkyl furoates with the remote location of functional groups were developed. Investigation of methanolysis of these compounds in presence of sodium methylate showed that complete transesterification of acetates is achived when the equimolar amount of base is used. It takes place due to high acidity of furan alcohols. If acetoxymethyl group is located in the position 3 of the furan ring, and diethoxyphosphorylmethyl one - in the position 2, cleavage of P-C bond takes place. If phosphonomethyl group is located in the position 3, and acetoxymethyl one occupies position 2 or 4, transesterification of ester groups of phosphonate takes place, but P-C bond is not touched. The ester group of carbonic acid is transesterified in any case. The alcohols formed are oxidized according to Kollins to give the corresponding aldehydes. 2-Furylbenzo[ d ]thiazole having ester and diethoxyphosphorylmethyl groups in the furan ring was synthesized by reacting methyl 2-(diethoxyphosphorylmethyl)-5-formylfuran-3-carboxylate with 2-aminothiophenol.

The mechanism of the reaction of vinylsilanes with N , N -dichlorotriflamide and the effect of a substituent at the silicon atom on the reaction course and on the charge distribution in substrates and their carbon analogues were studied by DFT method. The C=C bond in vinylsilanes and alkenes is polarized in the opposite way. The reaction proceeds in two stages: chlorination of the substrate with the formation of a chloronium ion, and its opening at the C_β-Cl bond by the N -chlorotriflamide anion. Transition states of two stages were calculated. The reaction products are hydrolyzed to NH-derivatives; their IR spectra and supramolecular structure, including cyclic and linear dimers, calculated in the gas phase and in a polar medium, were studied.

Aminolysis of ester derivatives of 1,1′-dinaphthylmethane and rctt -calix[4]resorcinarene afforded a series of ligands, which differ in molecular platform structure, the number of electron-donating sites, the nature of terminal amide component, the nature and size of the spacers connecting the polycyclic core with amide group. Using liquid extraction method, the effect of ligand structural features on its ability to recognize and bind s -, p -, d -, f -metal cations was investigated, and the stoichiometry of formed complexes was calculated.

The literature data of various research methods on the structural characteristics of the nearest environment of some monatomic inorganic cations in aqueous solutions and in acetonitrile under ambient conditions are summarized. A quantitative comparison of the cations first solvation shell structures in these solvents has been carried out. It is suggested that for these systems, the structure of solvation shells of cations do not depend on the solvent, but is determined only by the physicochemical nature of the ions.

A number of microemulsions based on oleic acid and Tween 80, modified with piperidinium surfactants, have been obtained and characterized. The effect of additives on the size, stability, and solubilization effect of the formed systems with respect to hydrophilic (rhodamine B) and hydrophobic (indomethacin) substances was studied. By varying the ratio of components, it was possible to form microemulsions that differ greatly in viscosity: from easy-flowing compositions to gels. The kinetic parameters describing release process of substrates from microemulsions have been obtained. In vivo tests of the anti-inflammatory action of microemulsions loaded with indomethacin have shown that the presence of piperidinium surfactants enhances the therapeutic effect of the drug. In vivo tests of the anti-inflammatory action of microemulsions loaded with indomethacin have shown that the presence of piperidinium surfactants enhances the therapeutic effect of the drug.