Medical oxygen is a critically needed medicine in the treatment of coronavirus disease. During out breaks of the COVID-19 pandemic, the needs of health care institutions for medical oxygen increase by 5-6 times. The issue of the reliable functioning of the oxygen supply system of health care institutions during the COVID-19 pandemic is extremely urgent and requires systematic research. The purpose of the work was to conduct research on measures to provide oxygen to health care facilities during the COVID-19 pandemic, to establish risk factors in its production and supply, and to determine priority directions for guaranteeing the ability to provide medical assistance in the treatment of coronavirus disease. The methods of systematic approach, bibliographic, information search, marketing analysis, as well as generalization and analysis were used during the research. The study showed that medical use of oxygen as a medicine, oxygen produced by medical devices, and technical oxygen was allowed at the state level. Domestic manufacturers produce medical oxygen that meets all regulatory requirements for medicinal products. In Ukraine, 36 drugs based on medical oxygen are registered, the production of which is carried out by 26 enterprises that have licenses for the production of medicinal products. During the pandemic, it was allowed for medical use of technical oxygen, which should meet the quality indicators of medical oxygen. The use of oxygen, which is produced by medical devices, which include oxygen generators and oxygen concentrators, which must meet the requirements of the Technical Regulations, became a significant measure for the expansion of oxygen therapy. During the implementation of all measures to provide oxygen, there are risks of a national and branch nature, as well as specific risks associated with the characteristics of different types of oxygen (oxygen as a medicine, oxygen produced by medical devices, technical oxygen). The identified list of risks and their analysis in the provision of oxygen to health care facilities during the COVID-19 pandemic will provide an opportunity to develop the concept of general risk assessment and risk management processes to guarantee the ability to provide adequate medical care in the treatment of coronavirus disease.
2-Hydroxybenzyl alcohol is an important active pharmaceutical ingredient for the production of many drugs, in particular gastrodin, which has a wide range of beneficial effects on epilepsy, Alzheimer’s disease, Parkinson’s disease, affective disorders, cerebral ischemia, cognitive disorders. It is known that 2- and 4-hydroxybenzyl alcohols and mixtures of both compounds are obtained by the interaction of phenol with formaldehyde in the presence of basic catalysts. Due to its high reactivity with formaldehyde, the isolation of pure compounds from the reaction mixtures obtained during the interaction of phenol with formaldehyde is a big problem. Isolation of 2-hydroxybenzyl alcohol in pure form from reaction mixtures is possible only using processes that cannot be carried out on an industrial scale and is accompanied by low yields of the target product. It is possible to get rid of these problems by means of the process of direct oxidation of the 2-hydroxytoluene with ozone in the liquid phase since methods of selective ozonation of methylbenzene to the oxygen derivatives are already known. Therefore, the development of a new low-temperature synthesis of 2-hydroxybenzyl alcohol using ozone is an urgent task. The aim of the work is to study the reaction of the oxidation of 2-hydroxytoluene by ozone in a solution of a stop reagent and catalytic impurities of compounds of transition metals and mineral acids for the development of a new method of synthesis of 2-hydroxybenzyl alcohol. Materials and methods. For the experiments, acetic anhydride of p. a. qualification was used; glacial acetic acid of puriss. qualification, which before use was purified by distillation under vacuum in the presence of potassium permanganate, 2-hydroxytoluene of puriss. Qualification, manganese (II) acetate of pur. Qualification, sulfuric and phosphoric acids of puriss. qualification. To determine the concentration of ozone in the gas phase, a spectrophotometric method was used, based on the measurement of the optical density of the gas flow in the UV region. For this purpose, a spectrophotometer SF-46 LOMO was used, in the measuring chamber of which a flow cuvette with quartz windows was installed. The material of the cuvette was Teflon. Continuous monitoring of the current concentration of ozone, with the recording of the analysis results in the form of a kinetic curve, was carried out when ozone-containing gas passed through the curette at a certain wavelength of a monochromatic light source. Results. The reaction of oxidation of 2-hydroxytoluene by ozone in a solution of the stop reagent – acetic anhydride was studied. It was shown that in the presence of sulfuric acid, it was possible to carry out direct ozonation of 2-hydroxytoluene to 2-hydroxybenzyl alcohol, which was formed in the kind of 2-acetoxybenzyl acetate with a yield of 13.0 %. The main products of the reaction under these conditions are aliphatic compounds, which are formed after the destruction of the aromatic ring. The selectivity of oxidation by alcohol was significantly increased when a catalyst – manganese (II) acetate – was added to the system. In its presence, a catalytic system As2O – H2SO4 – Mn(III) was created, which prevents ozonolysis and directed oxidation mainly to the methyl group of the substrate with the formation of 2-acetoxybenzyl acetate with a yield of 63.2 %. Conclusions. An environmentally friendly, low-temperature method for the synthesis of 2-hydroxybenzyl alcohol was developed by conducting the oxidation of 2-hydroxytoluene with ozone in a solution of the stop reagent – acetic anhydride in the presence of sulfuric acid and manganese (II) acetate.
Procaine is one of the oldest local anesthetics used in medicine. When absorbed and entering the systemic circulation reduces the excitability of peripheral cholinoreactive systems. Has a blocking effect on the autonomic ganglia, reduces smooth muscle spasms, and reduces the excitability of the myocardium and motor areas of the cerebral cortex. It is synthesized by oxidizing 4-nitrotoluene to 4-nitrobenzoic acid, which is subsequently reacted with thionyl chloride, the resulting acid chloride is then esterified with 2-diethylaminoethanol to give nitrocaine. Finally, the nitro group is reduced by hydrogenation over a Raney nickel catalyst. The oxidation stage is characterized by the formation of toxic, difficult to dispose of wastewater, valuable mineral oxidants, or high temperatures and excess pressure, in the case of using oxygen as an oxidant. Therefore, the search for new environmentally friendly and low-temperature methods of obtaining 4-nitrobenzoic acid is an urgent task. The aim of the work is to study the products, conditions, and study kinetics of the reaction of ozone with 4-nitrotoluene in acetic acid solution to develop a new method for the synthesis of 4-nitrobenzoic acid. Materials and methods. The glacial acetic acid qualification “P. F. A.” before use was purified by distillation under vacuum in the presence of potassium permanganate. Salts of metals of qualification “P. F. A.” and potassium bromide qualification “Ch. P.” were used without prior purification. A gas-phase gradient-free catalytic duck reactor was used for kinetic studies. The mixing of gas and liquid phases in the reactor was achieved by shaking the reactor at a speed that allowed it to work in the kinetic region. The kinetics of the reaction was studied by changing the concentration of ozone in the gas phase at the outlet of the reactor by spectrophotometric method on a spectrophotometer “SF-46 LOMO”. Results. The products, conditions, and kinetics of ozone reaction with 4-nitrotoluene were studied. It was shown that at temperatures of 20–90 °C is mainly ozonolysis of the aromatic ring, and the total yield of oxidation products by methyl group does not exceed 24.2 %, among which identified in the early stages of 4-nitrobenzyl alcohol and 4-nitrobenzaldehyde, and at deeper – 4-nitrobenzoic acid. The introduction of cobalt (II) acetate into the catalyst system almost completely was prevented ozonolysis and the main reaction product is 4-nitrobenzoic acid with a yield of 86.5 %. The addition of potassium bromide to the solution reduced the concentration of the catalyst by seven times and increased the reaction rate and yield of 4-nitrobenzoic acid to 95.6 %. Conclusions. A new environmentally friendly, low-temperature method for the synthesis of 4-nitrobenzoic acid by conducting the process of ozonation of 4-nitrotoluene in a solution of glacial acetic acid in the presence of a mixed cobalt bromide catalyst was developed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.