The article presents the synthesis of 2-arylimino-4-methyl-2,3-dihydro-1,3-thiazoles via Hantzsch reaction of thioureas and 3-chloropentane-2,4-dione or ethyl 2-chloro-3-oxobutanoate. The structure of synthesized compounds was confirmed by LCMS, ¹H, and ¹³C NMR spectra. Cardioprotective activity of synthesized thiazole derivatives were studied in vitro on the isolated rings of the thoracic aorta of laboratory rats. Based on pharmacological studies, the tested compounds possessed a moderate to high cardioprotective effect. A prospective 1-[2-(4-methoxyphenylimino)-4-methyl-3-(4-methylpiperazine-1-yl)-2,3-dihydro-1,3-thiazole-5-yl] ethan-1-one hydrochloride 4c was identified. The mentioned compound has delayed the development of constrictor responses of isolated rings of the thoracic rat aorta and exceeds the activity of L-carnitine by 18.2% and meldonium by 12.9%. The compound 4c may be proposed as a potential cardioprotective agent for in-depth pharmacological studies.

The purpose of our work was the search for safe and effective biologically active substances of cardiotropic action among 1,3- thiazole derivatives. New derivatives of 1-[(2Z)-2-[R-imin]-4-methyl-3-R¹-2,3-dihydro-1,3-thiazole-5-yl]ethan-1-one and ethyl-(2Z)-2-[R-imin]-4-methyl-3-R¹-2,3-dihydro-1,3-thiazole-5-carboxylate were synthesized by the Hantzsch reaction. The structure of the compounds obtained was confirmed by ¹H NMR spectroscopy and by the elemental analysis. The pharmacological screening showed that the obtained substances possess cardiotropic activity. The cardiotropic properties of the new 1,3-thiazole derivatives were studied on the isolated rings of the thoracic aorta of laboratory rats. A prospective substance 1-[(2Z)-2-[(4-methoxyphenyl)imin]-4-methyl-3-(4-methylpiperazin-1-yl) -2,3-dihydro-1,3-thiazol-5-yl]ethan-1-one hydrochloride, which exhibits cardiotropic activity exceeding the activity of L-carnitine and meldonia has been revealed during pharmacological researches of the substances obtained.