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.