The rapid development in bacterial resistance to many groups of known antibiotics forces the researchers to discover antibacterial drug candidates with previously unknown mechanisms of action, one of the most relevant being the inhibition of tRNA (Guanine37-N1)-methyltransferase (TrmD). The discovery of selective TrmD inhibitors in the series of carboxamide derivatives of thienopyrimidines became a background for further modification of the similar structures aimed at the development of promising antibacterial agents. As part of this research, we carried out the construction of heterocyclic hybrids bearing the moieties of thieno[2,3-d]pyrimidine and benzimidazole starting from 3,5-dimethyl-4-oxo-2-thioxo-1H-thieno[2,3-d]pyrimidine-6-carboxylic acid, which was used as the pivotal intermediate. The hybrid molecule of 6-(1H-benzimidazol-2-yl)-3,5-dimethyl-2-thioxo-1H-thieno[2,3-d]pyrimidin-4-one prepared via condensation of the carboxylic acid with ortho-phenylenediamine was further alkylated with aryl/hetaryl chloroacetamides and benzyl chloride to produce the series of S-alkyl derivatives. The results of molecular docking studies for the obtained series of S-alkyl benzimidazole-thienopyrimidines showed their high affinity to the TrmD isolated from the P. aeruginosa. The results of antimicrobial activity screening revealed the antimicrobial properties for all of the studied molecules against both Gram-positive and Gram-negative bacteria and the Candida albicans fungal strain. The highest antimicrobial activity was determined for 2-{[6-(1H-benzimidazol-2-yl)-3,5-dimethyl-4-oxo-3,4-dihydrothieno[2,3-d]pyrimidin-2-yl]thio}-N-(4-isopropylphenyl)acetamide, which also had the highest affinity to the TrmD inhibitor’s binding site according to the docking studies results.

The mechanism, protective properties, microstructure, phase composition of coats on steel have been investigated. According to the developed method, the coats were deposited potentiodynamically and potentiostatically in an aqueous solution of sodium tripolyphosphate. Based on the results of electrochemical studies, it has been established, that on potentiodynamic curves, characterizing the corrosion behavior of low-carbon steel in an aqueous sodium TPP solution, up to three passivation plateaus can be observed. The multi-stage formation mechanism of tripolyphosphate coat has been proposed. The mechanism includes three stages: at the start the adsorptive film is formed, that afterwards is modified two times, accompanied by a change of properties and composition. By using the methods of optical and scanning electron microscopy, X-ray diffraction, it has been established that the coat formed in an aqueous Na TPP solution by the potentiodynamic method under conditions of complete passivation, is composed of two layers: first – thin, compact layer, that contains a crystalline phase of phosphate nature, and second – thick hydrophilic layer, capable of drying. Such coat possesses the best protective properties in 0.1 N Na₂SO₄ solution, that models conditions of atmospheric corrosion. The nature of the electrochemical formation mechanism of tripolyphosphate coats and features of their structural and phase composition have been established. The further studies will be directed at the development of effective deposition methods of tripolyphosphate coats with estimated set of properties for the protection of metal goods from atmospheric and high-temperature gas corrosion.

The parallel solution-phase synthesis of a new combinatorial library of 3-[4-(R1-coumarin-3-yl)-1,3-thiazol-2-ylcarbamoyl]propanoic acid amides 9 has been developed. The synthesis involves two steps: 1) the synthesis of core building blocks – 3- [4-(coumarin-3-yl)-1,3-thiazol-2-ylcarbamoyl]propanoic acids, 6 – by the reaction of 3-(ω-bromacetyl)coumarins 1 with 3-amino(thioxo)methylcarbamoylpropanoic acid (5); 2) the synthesis of the corresponding 3-[4-(coumarin-3-yl)-1,3-thiazol-2-yl- carbamoyl]propanoic acids amides 9 using 1,1’-carbonyldimidazole as a coupling reagent. The advantages of the method compared to existing ones are discussed.

In the course of our research on the synthesis of coumarins, the interaction of 2-iminocoumarin-3-carboxamides with a series of 2-aminothiophene-3-carboxamides was studied. It was established that the initial products - 2-substituted coumarin-3-carboxamides - can undergo rearrangement to 2-(coumarin-3-yl)thieno[2,3-d]pyrimidin-4-ones by refluxing in DMF.

Layered double hydroxides with different ratios of nickel and aluminum in the presence of Ag + ions and without silver have been synthesized: Ni: Al – 80 %: 20 %, Ni: Al: Ag – 80 %: 15 %: 5 % and 75 %: 15 %: 5 %. The obtained nickel hydroxide powders have a structure similar to α-Ni(OH)₂ with a large number of crystal lattice defects. As a result of galvanostatic charge-discharge cycling, it was revealed that the addition of silver in the chemical synthesis stage increases the hydroxide utilization coefficient at fast discharges but decrease it at slow discharges. A possible mechanism that explains the influence of added silver during synthesis on discharge characteristics of hydroxide powders was proposed. The mechanism is that silver oxide, which is a semiconductor, is mixed with hydroxide and increases the specific conductivity of the powder. Increased electrical conductivity has a positive effect on charge effectiveness, because the initial phase has lower electrical conductivity than the oxidized form – NiOOH. Because the charge involves two processes – the main process of active material charging and evolution of molecular oxygen, the electrical conductivity would play a key role in the electrode charging. At low electrical conductivity and fast charge, the current would primarily be consumed by the side process of oxygen evolution. In case of slow charges, additional electrical conductivity due to the presence of silver oxide would not have a great effect on charge effectiveness, because under such conditions the own conductivity of hydroxide is sufficient. Additionally, the presence of silver oxide would decrease the hydroxide content, which in turn would decrease the utilization coefficient that is calculated from the total mass of the powder.