Репозитарій

UDC 615.073/.074:615.27:615.453.4:543.48:547.673.5

The aim of the work was to develop a simple, rapid, economic spectrophotometric method for the determination of meldonium in capsules based on the reaction with alizarin.
Materials and methods. Analytical equipment: double-beam UV-visible spectrophotometer Shimadzu UV 1800 (Japan), a pair of 1 cm matched quartz cells, software UV-Probe 2.62, laboratory electronic balance RAD WAG AS 200/C, pH-meter I-160МI. Pharmacopoeial standard sample (CRS) of meldonium dihydrate (Sigma-Aldrich, (≥98 %, HPLC)), alizarin (Synbias), capsules Metamax (Darnytsia) 250 mg, Vasopro (Farmak) 500 mg, Mildronate (Grindex) 500 mg, dimethylformamide (“Honeywell Riedel-de Haen”).
Results and discussion. A spectrophotometric method for determining meldonium in capsules by reaction with alizarine has been developed. The absorption maximum of the formed complex in dimethylformamide was at a wavelength of 517 nm. Stoichiometric ratios of reactive components «meldonium- alizarin» were 1:1. Validation of the developed analytical method for the determination of meldonium in medicines was carried out in accordance with the requirements of the SPhU. The optimal conditions for performing the quantitative determination of meldonium have been established: concentration of alizarin solution – 0.8 %, volume 0.8 % alizarin solution – 0.5 ml, heating time – 20 min, temperature – 95±2 °C. Linearity has been in the concentration range of 0.0402–0.1073 mg/mL, the limit of detection – 2.84 μg/mL, and the limit of quantification – 8.59 μg/mL. The eco-friendliness of the developed analytical method was carried out using the analytical eco-scale, AGREE, and GAPI methods.
Conclusions. The developed method can be used as an arbitration method for the routine analysis of meldonium capsules

The review considers the environmental problem of generation, accumulation and utilization of waste tires in Ukraine and the world. It is established that waste tires can serve as a valuable raw material for obtaining fuel components and technical/individual chemicals for further industrial processing. One of the promising methods for the rational utilization of waste tires may be their pyrolysis. The pyrolysis process of waste tires produces gaseous, liquid and solid carbonized residue. At the same time, there is no ideal universal technology for the use of waste tire pyrolysis products without preliminary treatment/purification methods. The main characteristics, processing methods and applications of products obtained from the pyrolysis of waste tires are briefly considered.

Fused systems combining 1,2,4-triazole and 1,3,4-thiadiazole rings occupy a prominent place in modern bioorganic and medicinal chemistry due to the diverse range of their biological activities. Thus, compounds incorporating [1,2,4]triazolo[3,4-b]thiadiazole ring system are of essential importance and particular interest both in the pharmaceutical as well as agrochemical industries. Herein, an overview of certain synthetic methodologies for obtaining of heterocyclic compounds based on functionally substituted 1,2,4-triazolo[3,4-b][1,3,4]thiadiazoles are presented.

Triazolo[3,4-b]thiadiazoles are a class of heterocyclic compounds, which have attracted great interest in medicinal chemistry owing to their wide range of pharmacological activities. A number of triazoles fused to thiadiazoles are incorporated into a wide variety of therapeutically important compounds possessing a broad spectrum of biological activities. Considering such a significant pharmacological potential, as well as wide synthetic possibilities triazolo-thiadiazoles have received considerable attention from scientific community and are extensively used for construction of prospective drug-likes molecules. In this review, we summarized the literature data about the main synthetic approaches for obtaining condensed heterocyclic compounds based on triazolo[3,4-b][1,3,4]thiadiazole scaffold as promising objects for modern bioorganic and medicinal chemistry. 

A bisphenol-formaldehyde resin was synthesized using the polycondensation method of bisphenol A with formaldehyde. Road bitumen has been modified with this resin. The possibility of its use as a road petroleum bitumen modifier has been established for different contents of the synthesized resin. It has been established that the introduction of synthesized bisphenol-formaldehyde resin into the composition of bitumen significantly increases its heat resistance. The synthesized resin and modified bitumens were characterized using IR spectroscopy. The change in the composition and properties of the bitumen modified with bisphenol-formaldehyde resin has been described.