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Abstract

The aim of this work is the study of stability and kinetics of hydrolysis of the chosen compounds, derivatives of 2-hydroxy-3-[2-(4-methoxyphenyl)ethylamino]propyl-4- [(alkoxycarbonyl)amino]benzoates and 2-hydroxy-3-[2-(2-methoxyphenyl)ethylamino] propyl-4-[(alkoxycarbonyl)amino]benzoates with potential ultra-short beta-adrenolytic activity. The studied compounds are different in the position of the substituent on the benzene ring in the side chain as well as in the aromatic ring in position 4 with alkyl- (methyl- to butyl-) carbamate. Thin layer chromatography and UV-area spectrophotometry are used in order to establish the stability of these potential pharmaceuticals. The stability studies of the compounds were examined in acidic and alkaline media, in buffers and due oxidation at room and at elevated temperature chromatographically, and Rf values of incipient products and degradation products were detected. Kinetics of acid and base hydrolysis in various solutions at temperatures 80 °C and 100 °C were examined through UV-area spectrophotometry. Kinetic parameters such as rate constant k, half-life period t1/2 and usable life t90 were determined.

kinetics of alkaline hydrolysis of 1-methyl-2-piperidinoethyl esters of alkyloxyphenylcarbamic acid. Pharmazie 1999;54:152-153. [14] Stankovičova M., Bezakova Ž., Beňo P.: Isothermal and nonisothermal study of kinetics of hydrolysis of potential drugs (in Slovak). Zbornik 38. Konferencie Synteza a analyza liečiv. Hradec Kralove, 2009, p. 143. [15] Treindl, L.: Chemical Kinetics (in Slovak). Bratislava: Slovak Pedagogical Publishing House; 1990. [16] Wells, J.I. Drug Stability. In: Pharmaceutical Preformulation Study - The Physicochemical Properties of Drug Substances

Study of stability of potential betaadrenolytics, derivatives of the [(arylcarbonyl)oxy]aminopropanol by kinetics of alkaline hydrolysis

This work deals with the study of the stability of six derivatives of the [(arylcarbonyl)oxy]amino propanol with carbamate substitution on the benzene ring. The studied compounds are different in the substitution on the amine group in the side chain as well as in the substitution on the carbamate functional group. The hydrolysis of compounds was measured in the aqueous-ethanol sodium hydroxide solution (0.1 mol.l-1) at 25, 37, 45 and 60°C spectrophotometrically in the ultraviolet and visual regions. The studied compounds possess two functional groups, which undergo hydrolysis. The pseudo-first order rate constants of hydrolysis for individual reaction steps were determined. The ester functional group of compounds hydrolyses very quickly in this medium. The compounds possessing the tertiary substitution on the amino group are less stable toward alkaline hydrolysis. The course of hydrolysis of compounds was also investigated by thin layer chromatography (TLC).

layer chromatography and by kinetics of hydrolysis. Acta Fac Pharm Univ Comenianae 2012;59:54–62. [9] Tanada, S., Kawakaka, N., Nakamura, T., Abe, I.: Adsorption of inhalation anaesthetics and hydrochlorofluorocarbons on activated carbons as a biological model. Chem Pharm Bull 1997;45:231-233.

moiety, Eur. J. Med. Chem . 45 (2010) 3293–3298; https://doi.org/10.1016/j.ejmech.2010.04.012 10. T. Benković, A. Kenđel, J. Parlov-Vuković, D. Kontrec, V. Chiş, S. Miljanić and N. Galić, Multiple dynamics of aroylhydrazone induced by mutual effect of solvent and light - spectroscopic and computational study, J. Mol. Liq . 255 (2018) 18–25; https://doi.org/10.1016/j.saa.2017.09.038 11. T. Benković, D. Kontrec, V. Tomišić, A. Budimir and N. Galić, Acid-base properties and kinetics of hydrolysis of aroylhydrazones derived from nicotinic acid hydrazide, J

-metal-protein complexes. J Appl. Polym. Sci. 65, 37-40. 7. Shoukry, M.M., Khairy, E.M. & El-Sherif, A.A. (2002). Ternary complexes involving copper(II) and amino acids, peptides and DNA constituents. The kinetics of hydrolysis of a-amino acid esters. Transit. Metal Chem. 27, 656-664. DOI: 10.1023/A:1019831618658. 8. Etaiw, S.E.D.H., Sultan, A.S. & El-Bendary, M.M. (2011). In vitro and in vivo antitumor activity of novel 3D-organotin supramolecular coordination polymers based on CuCN and pyridine bases. J. Organomet. Chem. 696, 1668-1676. DOI: 10.1016/j.jorganchem. 2011.02.003. 9

mRNA expression of apoptotic and inflammatory markers and gut morphology of piglets Czech Journal of Animal Science 53 377 387 Karl Schedle Kozlowska, H., Honke, J., Sadowska, J., Frias, J. and C. Vidal-Valverde (1996): Natural fermentation of lentils: Influence of time, concentration and temperature on the kinetics of hydrolysis of inositol phosphates. Journal of the Science of Food and Agriculture 71, 367–375. 10.1002/(SICI)1097-0010(199607)71:3<367::AID-JSFA591>3.0.CO;2-I Karl Schedle Kozlowska H. Honke J. Sadowska J. Frias J. Vidal-Valverde C. 1996 Natural