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Nowadays cardiovascular diseases are the main cause of death among the population around the word. The development of new drugs, giving a possibility to normalize blood pressure, is a promising direction in the field of pharmacy and medicine. Now inhibitors of angiotensinconverting enzyme (ACE) are widely adopted for the treatment of hypertension and chronic heart failure. The principle of action of ACE inhibitors is based on blocking the conversion of angiotensin I into angiotensin II, which mediates vasodilation.The aim of the work is a selection of methods of lisinopril interaction with the active center of angiotensin-converting enzyme by molecular dynamics methods.Materials and methods. Lisinopril molecule was used as a ligand; the charges of that ligand were calculated with the density functional theory (DFT) and ub3lyp method with the basis sets 6-31G* and 6-311G**. Simulation of 75 ns of molecular dynamics of lisinopril interaction with the active center of ACE was carried out in the Bioevrica program. As a result of molecular dynamics simulation, the trajectory of the “lisinopril-ACE” system was obtained. After that a comparison of ligand conformations at different points in simulation time with the experimental conformation of the value of standard deviation of coordinates of atoms was made.Results and discussion.The results of simulation have showed that lisinopril with the charges corresponding to basis set 6-311G** behaves consistent with the x-ray data in the active center of the ACE, in contrast to lisinopril with the charges calculated by basis set 6-31G*.Conclusion. The methods of lisinopril interaction modeling with the active center of angiotensin-converting enzyme has been selected. The obtained technique can be used for studying the interaction of substances, similar in structure to lisinopril with the active center of the enzyme (ACE).

An efficient approach for construction of physically justified STO(II)-3Gmag family basis sets for calculation of molecules magnetic properties has been proposed. The procedure of construction based upon the taken into account the second order of perturbation theory in the magnetic field case. Analytical form of correction functions has been obtained using the closed representation of the Green functions by the solution of nonhomogeneous Schrödinger equation for the model problem of "one-electron atom in the external uniform magnetic field". Their performance has been evaluated for the DFT level calculations carried out with a number of functionals. The test calculations of magnetic susceptibility and 1H nuclear magnetic shielding tensors demonstrated a good agreement of the calculated values with the experimental data.

Theoretical investigations of the conformational properties and 1H NMR chemical shifts for N-methyl-4-tolyl-1-(4-bromonaphthyl)amine and N-phenyl-1-(4-bromonaphthyl)amine are reported. The calculations were performed at the DFT level (PBE1PBE functional) using magnetically consistent 6-31G## and STO##-3Gmag basis sets. Conformational properties of the amines were studied using potential energy surface scanning. Chemical shifts were calculated using the GIAO and CSGT methods and averaged in proportion to the population of the corresponding conformations. Solvent effects (CDCl3) were accounted via PCM method. The obtained results allowed to assign the 1H NMR signals for the naphthalene moiety, which could not be done based on the experimental data alone.