Comparative Assessment of the Ideas About Doping Among Athletes Involved in Athletics and Table Tennis

В статье представлены результаты исследования, проведенного у юных спортсменов, занимающихся легкой атлетикой и настольным теннисом, с целью оценки уровня знаний о допинге. В ходе исследования для выявления осведомленности о запрещенных веществах и последствиях использования допинга, а также с целью выявления понимания проблемы допинга был проведен опрос спортсменов.This article presents the results of a study conducted to assess the level of knowledge about doping among track and field athletes and table tennis players. The study included a survey of athletes to determine their understanding of the problem of doping, awareness of prohibited substances, and the consequences of doping

Reductive Amination without an External Hydrogen Source

A method of reductive amination without an external hydrogen source is reported. Carbon monoxide is used as the reductant. The reaction proceeds efficiently for a variety of carbonyl compounds and amines at low catalyst loadings and is mechanistically interesting as it does not seem to involve molecular hydrogen

Hydrogen-free reductive amination using iron pentacarbonyl as a reducing agent

We developed solvent-free reductive amination without an external hydrogen source using iron pentacarbonyl as a reducing agent. Neither a catalyst nor any other additives were employed. Various types of substrates are suitable for the reaction, including those with low reactivity, e.g. benzophenone. Among others, the protocol tolerates bromo-, cyano-, benzyloxy-, pyrimidyl and styryl moieties. © 2017 The Royal Society of Chemistry

Dichotomy of reductive addition of amines to cyclopropyl ketones vs pyrrolidine synthesis

An interesting catalytic dichotomy was discovered: switching between simple ligand-free catalysts leads to fundamentally different outcomes of reductive reaction between amines and α-carbonylcyclopropanes. Whereas a rhodium catalyst leads to the traditional reductive amination product, ruthenium catalysis enables a novel reaction of pyrrolidine synthesis via ring expansion. The protocols do not require an external hydrogen source and employ carbon monoxide as a deoxygenative agent. The developed methodologies are perfectly compatible with a number of synthetically important functionalities such as ester, carboxyl, bromo, and Cbz moieties. © 2016 American Chemical Society

Hydrogen-free reductive amination using iron pentacarbonyl as a reducing agent

We developed solvent-free reductive amination without an external hydrogen source using iron pentacarbonyl as a reducing agent. Neither a catalyst nor any other additives were employed. Various types of substrates are suitable for the reaction, including those with low reactivity, e.g. benzophenone. Among others, the protocol tolerates bromo-, cyano-, benzyloxy-, pyrimidyl and styryl moieties. © 2017 The Royal Society of Chemistry

Dichotomy of reductive addition of amines to cyclopropyl ketones vs pyrrolidine synthesis

An interesting catalytic dichotomy was discovered: switching between simple ligand-free catalysts leads to fundamentally different outcomes of reductive reaction between amines and α-carbonylcyclopropanes. Whereas a rhodium catalyst leads to the traditional reductive amination product, ruthenium catalysis enables a novel reaction of pyrrolidine synthesis via ring expansion. The protocols do not require an external hydrogen source and employ carbon monoxide as a deoxygenative agent. The developed methodologies are perfectly compatible with a number of synthetically important functionalities such as ester, carboxyl, bromo, and Cbz moieties. © 2016 American Chemical Society

Development of a Two-Temperature Mathematical Model of Plasma Processes in a Discharge Chamber of a Multi-chamber Arrester Operating in Conditions of Mountain Areas

This article is devoted to a development of a mathematical model of plasma processes in a discharge chamber of a multi-chamber arrester operating under reduced pressure. The results obtained using this model will make it possible to develop recommendations on modifying the design of multi-chamber arresters for operation in conditions of mountain areas.A composition, thermodynamic and transport properties of plasma for the two-temperature model were calculated on the basis of the data on the materials of the discharge chamber and on the basis of the experiments performed earlier.The paper presents the results of calculations i.e. distributions of discharge voltage and electrical conductivity on time at various pressures. A comparison of obtained results was carried out

New approaches for the reductive formation of the C-N bond

This work was supported by the Grant for Young Scientists (No. MK-520.2017.3) and RUDN University Program “5-100”

Experimental substantiation of selection of fuel channel imitator for hydrodynamic model of nuclear reactor

Description is given of the methodology for experimental substantiation of hydrodynamic characteristics of imitators of fuel channels in the model of reactor unit with two-loop configuration. It is known from the experience of development of reactor units of different types that it is practically not feasible to select the channel to serve as the imitator with simple geometry for which the dependence of pressure drop due to hydraulic losses would be the same as the dependence for full-scale operating fuel channel containing fuel assemblies. Therefore, only approximate modeling of hydraulic losses in operational fuel channels with fuel assemblies and imitating channels within the limited range of Reynolds numbers can be discussed as well as inclusion of all coolant flow regimes within the reactor vessel predicted by design calculations. Selection of final geometry of imitating channels was made based on the following several basic assumptions of approximate modeling of flow path in the full-scale fuel channel with fuel assembly under nominal operational mode of the nuclear reactor using the channel with simplified geometry: (1) range of variation of coolant flow rates in the operational fuel channel with fuel assembly in nominal operational mode of the reactor is known from physical and from preliminary thermal physics calculation studies; (2) equality of Euler numbers for nominal coolant flow regimes in the reactor and for coolant flow in imitating channels. Experiments were conducted with three types of imitators and the most suitable among them was chosen as the result. The finally selected design of imitating channel included a pipe with high-quality of manufacturing, two diaphragms and a nozzle with configured using the method suggested by Vitoshinsky

Reductive Amination in the Synthesis of Pharmaceuticals

Reductive amination plays a paramount role in pharmaceutical and medicinal chemistry owing to its synthetic merits and the ubiquitous presence of amines among biologically active compounds. It is one of the key approaches to C-N bond construction due to its operational easiness and a wide toolbox of protocols. Recent studies show that at least a quarter of C-N bond-forming reactions in the pharmaceutical industry are performed via reductive amination. This Review concisely compiles information on 71 medical substances that are synthesized by reductive amination. Compounds are grouped according to the principle of action, which includes drugs affecting the central nervous system, drugs affecting the cardiovascular system, anticancer drugs, antibiotics, antiviral and antifungal medicines, drugs affecting the urinary system, drugs affecting the respiratory system, antidiabetic medications, drugs affecting the gastrointestinal tract, and drugs regulating metabolic processes. A general synthetic scheme is provided for each compound, and the description is focused on reductive amination steps. The green chemistry metric of reaction mass efficiency was calculated for all reactions. © 2019 American Chemical Society