The method for the synthesis of ethyl 4-[3-(ethoxycarbonyl)-1-phenyl-1H-pyrazol-4-yl]-2-oxo/thioxo-1,2,3,4-tetrahydropyrimidine-5-carboxylates was developed, and the bioactivity of the obtained compounds against infectious agents was predicted. Docking studies of the synthesised compounds were performed on pteridine reductase 1 (PTR1) of Leishmania, dihydrofolate reductase–thymidylate synthase of Trypanosoma cruzi, and human dihydrofolate reductase. The results demonstrated that the investigated compounds exhibit high affinity for these enzymes. Moderate selectivity relative to human DHFR was also observed. In addition, the predicted drug-likeness, ADME-Tox parameters, and toxicity profiles suggest the potential of the synthesised compounds for further pharmacological development.

A combined experimental and theoretical study of the fundamental thermodynamic parameters of 3-(5-phenyl-1-(pyridin-3-yl)-1H-pyrrol-2-yl)propanoic acid was carried out for the first time. The enthalpies of combustion, formation in the condensed state, fusion, and vaporization were determined using high-precision equipment. Based on the experimentally obtained results, the enthalpies of sublimation and formation in the gaseous state at 298.15 K were calculated using two methods. The possibility of applying analytical methods of Domalski, Joback and quantum chemical calculations to determine the enthalpy of formation in the gas phase is analysed.

The new fully substituted (1H-1,2,3-triazol-4-yl)acetic acids were synthesized from available precursors (1H-1,2,3-triazol-4-yl)ethanones and 1Н-1,2,3-triazole-4-carboxylic acids, which are easily prepared by the Dimroth reaction from azides and 1,3-dicarbonyl compounds. The practical methods of homologization (the Arndt–Eistert reaction and homologization as a result of nucleophilic substitution by cyanide anion) and the Willgerodt-Kindler reaction were compared. The Willgerodt-Kindler method starting from (5-methyl-1H-1,2,3-triazol-4-yl)ethanones was selected as the most convenient method for the synthesis of 2-(1-aryl-5-methyl-1H-1,2,3-triazol-4-yl)acetic acids, which are promising building blocks for drug discovery. Additionally, (1H-1,2,3-triazol-4-yl)ethanones were studied for the synthesis of alcohols, amines and in the Johnson–Corey–Chaykovsky reaction.