Compounds with positive inotropic activity, III: Synthesis of 4-aminoquinoline derivatives as potential positive inotropic agents

Anilinoacrylic acid derivatives 2-4 are the key intermediates from which 1-alkyl substituted 4-aminoquinoline 10-15 as well as 4-alkylaminoquinoline derivatives 16-23 are synthesized and examined for positive inotropic activity on isolated left atria and papillary muscles from guinea-pig. Structure activity relationships indicate that the effect depends on the alkyl side chain of the target compounds.