This paper describes the construction of the short-term forecasting model of cryptocurrencies’ prices using machine learning approach. The modified model of Binary Auto Regressive Tree (BART) is adapted from the standard models of regression trees and the data of the time series. BART combines the classic algorithm classification and regression trees (C&RT) and autoregressive models ARIMA. Using the BART model, we made a short-term forecast (from 5 to 30 days) for the 3 most capitalized cryptocurrencies: Bitcoin, Ethereum and Ripple. We found that the proposed approach was more accurate than the ARIMA-ARFIMA models in forecasting cryptocurrencies time series both in the periods of slow rising (falling) and in the periods of transition dynamics (change of trend).

The physicochemical properties of the new anxiolytic drug afobazole, which belongs to the group of 2-mercaptobenzimidazole derivatives, have been studied with a view to its pharmacopoeial standardization. It is suggested to check afobazole for the presence of impurities by means of TLC and HPLC. Methods for the standardization of afobazole are developed and a project for the pharmacopoeial article of manufacturer for this drug is formulated.As is known, the class of 2-mercaptobenzimidazole derivatives contains substances possessing gastroprotector, adaptogen, cardiotropic, and anxiolytic properties [1]. The new original domestic drug afobazole also belonging to this class and exhibits pronounced anxiolytic action that is not accompanied by side effects typical of tranquilizers of the benzodiazepine series [2]. Afobazole does not produce sedative (calming), hypnotic, and myorelaxant effects. At present, this drug is in the stage of clinical testing as a specific anxiolytic agent.The chemical structure of afobazole corresponds to 5-ethoxy-2-[2-(morpholino)ethylthio]benzimidazole dihydrochloride.The parent substance is synthesized via the alkylation of 5-ethoxybenzimidazole-2-thione with N-(2-chloroethyl)morpholine hydrochloride. The reaction proceeds on boiling in an alkaline aqueous alcohol medium. The reaction product is isolated by extraction with chloroform. The technical product is obtained by adding a hydrogen chloride solution in anhydrous ethanol to the base solution in an organic solvent until obtaining pH 1 -2. Finally, pharmacopoeial afobazole is obtained by recrystallization from ethanol.The present investigation was aimed at determining the physicochemical properties of afobazole, developing analytical procedures for the identification and determination of afobazole, and establishing maximum storage duration and justified parameters of quality of the parent substance I. EXPERIMENTAL PARTAfobazole appears as a crystalline powder of white color, sometimes with a creamy tint, readily soluble in water (1 g per 5 -8 ml), sparingly soluble in ethyl alcohol (1 g per 13 -14 ml), slightly soluble in chloroform (1 g per 275 -280 ml), and practically insoluble in ether (1 g is not dissolved in 100,000 ml).The parent compound was characterized with respect to the drug solution transparency, color, and pH at a concentration of 1%. This solution is virtually colorless (coloration does not exceed 7b grade standard). With respect to transparency, the optical density of 1% afobazole solution does not exceed turbidity standard I. The 1% aqueous afobazole solution has pH within 2.0 -3.0.The afobazole composition and structure are confirmed by elemental analyses and spectroscopic measurements. The IR spectra in the 4000 -400 cm -1 wavenumber range were recorded on a Perkin-Elmer Model 580 spectrophotometer (Sweden) using samples prepared as KBr pellets or nujol mulls. Since it was found that the characteristic absorption bands of afobazole were more clearly pronounced in the spectra of samples palletized with KBr, this me...

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Cardiocyclide, a new Russian class III antiarrhythmic agent, was developed at the State V. V. Zakusov Science Research Institute Pharmacology, Russian Academy of Medical Sciences. The aims of the present work were to study the physicochemical properties of the hydrochloride salt of this agent (N 1 -(3-diethylaminopropyl)-N 1 -(p-nitrobenzoyl)aminoacetic acid N,N-dicyclohexylamide HCl) and to develop an analytical method for this compound. IR, 1 H NMR, and UV spectra were obtained for cardiocyclide; its solubility was studied; its melting temperature, weight loss on drying and the transparency, color, and pH of its solutions were determined. The purity of material containing compound I was determined by thin-layer chromatography; quantitative cardiocyclide contents were estimated by non-aqueous titration.