S.A. Zolotov Director for Production and Development of OTC and API, AMEDART LLC (Moscow, Russia) E-mail: E.S. Ponomarev Technologist, AMEDART LLC (Moscow, Russia) E-mail: I.A. Dain Ph.D. (Chem.), Chief Technologist, AMEDART LLC (Moscow, Russia) E-mail: N.B. Demina Dr.Sc. (Pharm.), Professor, Department of Pharmaceutical Technology, Institute of Pharmacy, I.M. Sechenov First Moscow State Medical University of the Ministry of Healthcare of the Russian Federation (Sechenov University) (Moscow, Russia) E-mail: A.S. Zolotova Ph.D. (Pharm.), AMEDART LLC (Moscow, Russia) E-mail: V.M. Retivov Ph.D. (Chem.), Deputy Director for Chemical Research and Technology, National Research Center "Kurchatov Institute" (Moscow, Russia) E-mail: G.A. Buzanov Ph. D. (Chem.), Senior Research Scientist, Laboratory of Chemistry of Light Elements and Clusters, Institute of General and Inorganic Chemistry n.a. N.S. Kurnakov of RAS (IONC RAS) (Moscow, Russia) E-mail:

The aim of the work was to study the physicochemical properties of the domestic active pharmaceutical substance efavirenz produced by AMEDART LLC of the Russian Federation. Modern methods are used: differential scanning calorimetry, X-ray powder diffraction, spectral emission microscopy, high performance liquid chroma-tography, etc. The melting point, lipophilicity coefficient, wave numbers, shape and size of crystal particles, solubility in the biological pH range and in some organic solvents were determined. It has been established that the studied API has a minimum endothermic peak in the region of 140°C, the obtained lipophilicity coefficient is 4.67, it is practically insoluble in aqueous media in the biological pH range, but it is well soluble in most polar organic solvents, such as: methanol, ethyl alcohol, acetone and tetrahydrofuran, has a crystalline structure in the form of sticks from 3 to 18 microns and irregularly shaped particles from 1 to 7 microns in size, as well as wave numbers – angles of 6.1, 6.4, 10.4, 11.0, 12.3, 13.3, 14.2, 16.9, 20.1, 21.3, 24.9. DSC, IR spectrometry and X-ray powder diffraction data showed that the substance is a polymorph form I.


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