Abstract: Substituted thienyl-acetic acid esters of the formula: ##STR1## in which R.sub.1 and R.sub.2 each, independently is H, CH.sub.3, C.sub.2 H.sub.5, C.sub.3 H.sub.7, OCH.sub.3, SCH.sub.3, Cl Br or NO.sub.2, R.sub.3 is phenyl or cyclohexyl and R.sub.4 is H, or R.sub.3 and R.sub.4 together are cyclohexylidene, n is 2 or 3, and A is monoalkylamino or dialkylamino, each alkyl radical having 1 to 4 carbon atoms, or amino derived from a cycloalkylamine of 5 to 7 chain members which may contain an additional hetero-atom, provided that each of R.sub.1 and R.sub.2 is not H if R.sub.3 is phenyl or cyclohexyl and R.sub.4 is H, racemates, optical isomers, and their pharmaceutically acceptable acid addition salts and quaternary ammonium salts obtained with alkyl halides, have marked activity as peripheral vasodilators, platelet aggregation inhibitors, spasmolytic agents, coronary and cerebral vasodilators, and papaverine-like activity.