Application of Bioisosterism in Development of Novel Cardiotonics Based on (2'-Aminoethyl)carbostyril and (2'-Aminoethyl)-1-hydroxy-2-pyridone Systems

Two different types of chemical manipulations of dobutamine were investigated in order to develop novel, improved cardiotonic drugs. Three new analogues of carbostyril, in which the m-hydroxy group of dobutamine was isosterically modified with an amide type carbostyril system, were synthesized from, ${\rho}-methoxyphenethylamine$ via multi-steps. Two analogues of (2'-aminoethyl)-1-hydroxy-2-pyridone system which has isosteric structural similarity with dopamine without having the COMT vulnerable m-hydroxy group were synthesized via 12 synthetic steps. Their biological stabilities in various media and inotropic activities were evaluated.