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Water-insoluble polyelectrolyte complexes of cellulose acetate sulphate in the form of sodium salt (Na-CAS) and aminoglycoside antibiotic (AB) kanamycin (KAN) were obtained by mixing of the components aqueous solutions. The composition of the complexes was determined in accordance with the medium pH and mixing order. The increase of Na‑CAS cellobiose units per mole of AB has been shown to correlate with the decrease of pH value. The complex formation was studied by Fourier transform infrared spectroscopy, thermal analysis, X-ray analysis, laser diffraction, motion trajectory of nanoparticles analysis and scanning electron microscopy. Quantum-chemical study of the relative stability of the protonated forms of KAN in aqueous solution was performed to determine the preferred protonation sites of KAN molecule. The pKa values of KAN were calculated by means of isodesmic reactions method. The structures and binding energy for the KAN dimer and the KAN – CAS complex were also investigated by quantum-chemical methods. Na‑CAS – KAN complex itself and immobilised on the activated carbon was shown to demonstrate in vitro two times antibacterial activity of the standard (injectable) form of KAN against Mycobacterium tuberculosis. It can be recommended for in vivo clinical trials as a new form of aminoglycoside AB for oral administration.

Tetrazolium-5-aminides have been prepared by the tert-butylation of 5-aminotetrazole and its N-methyl derivatives by the t-BuOH/HClO4 system followed by the treatment of the tetrazolium salts by alkali. The mesoionic compounds have been found to show a higher reactivity of the exocyclic N atom in comparison with 5-aminotetrazoles. The compounds reacted with 1,2-dibromoethane and 5-(methylsulfonyl)-1-phenyl-1H-tetrazole with substitution of bromine and methylsulfonyl groups giving the corresponding tetrazolium salts or conjugate aminides. The obtained mesoionic tetrazoles have been characterized by elemental analysis, FTIR, NMR, and UV–vis spectroscopy, TGA/DSC analysis and for 1,3-di-tert-butyltetrazolium-5-aminide, its N,N’-ethylene-bridged bis-derivative and (1,3-di-tert-butyl-1H-tetrazol-3-ium-5-yl)(1-phenyl-1H-tetrazol-5-yl)amide by single crystal X-ray analysis. The structural and spectral features of the tetrazolium-5-aminides are discussed by using quantum-chemical calculations.

The crystalline complexes CuL2X2 and CuL4X2 , where X = Cl or X = Br were synthesized by the interaction of copper(II) chloride or bromide with 1-tert-butyl-1,2,4-triazole (L) in water or organic solvents. The structure of metal complexes have been studied by elemental analysis, X-ray analysis and IR-spectroscopy in the medium (4000 –500 cm –1 ) and long-wavelength (400–50 cm –1 ) regions. Quantum chemical calculations of the vibrational spectra of the CuL2Cl2 and CuL4Cl2 complexes have been carried out to perform the assignment of the signals in the IR-spectra. It is shown that the polymer structure of CuL2X2 complexes is formed due to bridging of one of their halide ions. In the CuL4X2 complexes, the halide ions and 1-tert-butyl-1,2,4-triazole form an island type structure. In all metal complexes 1-tert-butyl-1,2,4-triazole is coordinated by N(4) atom of heterocycle.

The purpose of the study is to design synthetic methodologies, especially directed deprotometalation using polar organometallic reagents, to access polysubstituted ferrocenesulfoxides. From enantiopure 2-substituted (SiMe3, PPh2) S-tert-butylferrocenesulfoxides, a third substituent was first introduced at the 5 position (SiMe3, I, D, C(OH)Ph2, Me, PPh2, CH2NMe2, F) and removal of the trimethylsilyl group then afforded 2-substituted ferrocenesulfoxides unreachable otherwise. Attempts to apply the “halogen dance” reaction to the ferrocenesulfoxide series led to unexpected results although rationalized in light of calculated pKa values. Further functionalizations were also possible. Thus, new enantiopure, planar chiral di- and trisubstituted ferrocenes have been obtained, in addition to several original 2-substituted, 2,3- and 2,5-disubstituted, 2,3,5-trisubstituted and even 2,3,4,5-tetrasubstituted ferrocenesulfoxides, also enantiopure.

Nucleophilic substitution of nitro group in N-alkyl-3-nitro-1,2,4-triazoles molecules with alicyclic alcohols (cyclohexanol, menthol) and polyatomic phenols (pyrocatechol, resorcinol) in the gas phase and in aqueous solution was studied by means of quantum-chemical calculations. The results of calculations show that nucleophilic substitution of the nitro group attached to the triazole ring under action of alicyclic alcohols is thermodynamically possible both in the gas phase and in aqueous solution. Among the isomeric N-alkyl-3-nitro-1,2,4-triazoles, the lowest value of ∆rG corresponds to the N(2)-isomer. Calculated values of ∆rG are appreciably higher for polyatomic phenols in comparison with alicyclic alcohols. The reactions of 1-alkyl-3-nitro-1,2,4-triazoles with resorcinol and pyrocatechol in aqueous solution are characterized by small negative or positive values of ∆rG. So, nucleophilic substitution is reversible in this case. At the same time, the process is irreversible for the corresponding anions (when reactions take place in alkaline media).

Five protocols were first compared for the copper-catalyzed C-N bond formation between 7-azaindole and aryl/heteroaryl iodides/bromides. The 1-arylated 7-azaindoles thus obtained were subjected to deprotometalation-iodolysis sequences using lithium 2,2,6,6-tetramethylpiperidide as the base and the corresponding zinc diamide as an in situ trap. The reactivity of the substrate was discussed in light of the calculated atomic charges and the pKa values. The behavior of the 1-arylated 7-azaindoles in direct iodination was then studied, and the results explained by considering the HOMO orbital coefficients and the atomic charges. Finally, some of the iodides generated, generally original, were involved in the N-arylation of indole. While crystallographic data were collected for fifteen of the synthesized compounds, biological properties (antimicrobial, antifungal and antioxidant activity) were evaluated for others.

The synthesis of N-arylated pyrroles and indoles is documented, as well as their functionalization by deprotonative metallation using the base in situ prepared from LiTMP and ZnCl2·TMEDA (1/3 equiv). With N-phenylpyrrole and -indole, the reactions were carried out in hexane containing TMEDA which regioselectively afforded the 2-iodo derivatives after subsequent iodolysis. With pyrroles and indoles bearing N-substituents such as 2-thienyl, 3-pyridyl, 4-methoxyphenyl and 4-bromophenyl, the reactions all took place on the substituent, at the position either adjacent to the heteroatom (S, N) or ortho to the heteroatom-containing substituent (OMe, Br). The CH acidities of the substrates were determined in THF solution using the DFT B3LYP method in order to rationalize the experimental results.