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.