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Interactions in lanthanide—amino acid—β-cyclodextrin systems (amino acid = tryptophan, phenylalanine; lanthanide = Eu3+, Pr3+) were studied in aqueous solution. An analysis of the chemical shifts observed in the 1H NMR spectra, as well as the ROESY data suggest the possibility for amino acid—lanthanide ion complexes encapsulated in the β-cyclodextrin cavity to form in solution. According to ROESY data, the indole ring of tryptophan and the phenyl group of phenylalanine enter the β-CD cavity from the wide rim side. Coordination with the metal ion occurs through the amino acid carboxyl group.

Inclusion complex of 4-acetoxy-1-(2-ethoxyethyl)-4-phenylpiperidine with β-cyclodextrin was synthesized. Composition (1:2) and the structure of the complex were confirmed by NMR spectroscopy and thermal analysis. The results of pharmacological studies showed that the compound is of interest for in-depth testing, because of its deeper and more prolonged conduction anaesthesia, terminal (superficial) and infiltration anaesthesia along with less acute toxicity compared to the reference preparations.

Specific features of the structure of the synthesized inclusion complex of 4-acetoxy-1-(2ethoxyethyl)-4-phenylpiperidine with β-cyclodextrin were considered. The composition (1: 2) and structure of the obtained complex were confirmed by NMR spectroscopy, thermal analysis, and quantum chemical calculations.

A method is developed for measuring the content of hydrogen (2Н) and oxygen (17O) isotopes in liquid media based on quantitative nuclear magnetic resonance. It has been established that the shifting europium trifluoromethanesulfonate (III) reagent is the most appropriate chemical compound for a reference sample to study the isotopic composition of aqueous solutions. A dependence of the paramagnetic chemical shift of 2Н and 17O nuclei on the concentration of Eu3+ ions in a solution is studied.