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We proposed and investigated a refinement of technology for obtaining Mg-doped LiNbO 3 (LN) crystals by co-doping it with B. LN:Mg (5.0 mol%) is now the most widely used material based on bulk lithium niobate. It is suitable for light modulation and transformation. We found that non-metal boron decreases threshold concentrations of the target dopant in many ways. In addition, we earlier determined that the method of boron introduction into the LN charge strongly affects the LN:B crystal structure. So we investigated the point structural defects of two series of LN:Mg:B crystals obtained by different doping methods, in which the stage of dopant introduction was different. We investigated the features of boron cation localization in LN:Mg:B single crystals. We conducted the study using XRD (X-ray diffraction) analysis. We have confirmed that the homogeneous doping method introduces an additional defect (Mg V ) into the structure of LN:Mg:B single crystals. Vacancies in niobium positions (V Nb ) are formed as a compensator for the excess positive charge of point structural defects. According to model calculations, boron is localized in most cases in the tetrahedron face common with the vacant niobium octahedron from the first layer (V Nb I O 6 ). The energy of the Coulomb interaction is minimal in the LN:Mg:B crystal (2.57 mol% MgO and 0.42 × 10 -4 wt% B in the crystal); it was obtained using the solid-phase doping technology. The solid-phase doping technology is better suited for obtaining boron-containing crystals with properties characteristic of double-doped crystals (LN:Mg:B).

A powerful synthetic strategy for the asymmetric synthesis of enantiomerically enriched γ-functionalized α-amino acid derivatives based on the highly stereoselective proline-catalyzed Mannich-type reaction of pre-prepared or in situ -generated γ-pyrone-derived aldimines with carbonyl compounds and subsequent transformations of multifunctional reaction products has been developed. A significant positive nonlinear effect was detected for the key organocatalytic reaction. The developed strategy was applied for facile gram-scale preparation of ( S )-γ-oxonorvaline, used for site-specific modification of proteins, and both enantiomers of amycolatolide A recently isolated from the lichen-derived actinomycete Amycolatopsis sp. YIM 130923.

Bronchodilator combipek of Russian produce was tested in 43 patients with bronchial asthma of various severity. Combipek contains 200 mg of theophylline and 8 mg of salbutamol. Pharmacokinetics of the drug was evaluated after a single administration and upon obtaining equilibrium concentration. Functional and clinical evidence showed a prolonged effect and safety of the drug in long-term treatment of bronchial asthma. Adverse effects emerged in 13 (30.2%) patients. They were typical for theophylline and beta 2-adrenostimulators. Combipek is advocated as a treatment of choice in patients with nocturnal asphyxia, in those who can hardly tolerate large doses of theophylline and beta 2-adrenostimulators.

The effects of placebo and proxodolol, a new hybrid (beta-, alpha-) adrenoblocking agent, on exercise tolerance, hemodynamics and the conduction system were compared in 28 patients with coronary heart disease, Functional Class II-III exercise-induced angina pectoris at rest and during bicycle ergometric exercise test. Proxodolol was shown to exert a significant dose-dependent antianginal effect without producing any negative effect on atrioventricular and intraventricular conduction.

The antihypertensive efficacy and hemodynamic effects of the new hybrid (beta-, alpha-) adrenoceptor blocking agent proxodolol were studied in 74 patients with mild, moderate, and severe arterial hypertension who received a single dose of 10, 20, or 40 mg. Oral and intravenous proxodolol showed a significant dose-dependent antihypertensive action which was independent of the type of hemodynamics and manifested itself by decreasing cardiac output.