Abstract: A fused thiophene compound of the formula: ##STR1## or a pharmaceutically acceptable acid addition salt thereof. In the above formula, one of E.sup.1, E.sup.2 and E.sup.3 is sulfur atom and other two of them are C--R.sup.1 and C--R.sup.2 respectively. R.sup.1 and R.sup.2 are the same or different and each is hydrogen, halogen, nitro, amino, cyano, hydroxyl, formyl, alkyl, alkoxy, haloalkyl, arylalkyl, acyl, alkoxyalkyl, acyloxyalkyl, hydroxyalkyl, acyloxyalkanoyl, alkoxyalkanoyl, hydroxyalkanoyl, aryloxyalkanoyl, haloalkanoyl, alkylthio, alkylsulfinyl, alkylsulfonyl, arylthio, arylsulfinyl, arylsulfonyl, hydroxysulfonyl, halosulfonyl, sulfamoyl, substituted sulfamoyl, carboxyl, acylamino, alkoxycharbonyl, carbamoyl, substituted carbamoyl or substituted amino. D is --CH.sub.2 -- or --S(O).sub.m -- (m is 0, 1 or 2). Q is straight or branched chain alkylene. T is primary amino, secondary amino or tertiary amino.