Aromatic amidine derivatives and salts thereof

A compound of formula (4), or a pharmaceutically acceptable salt thereof:

• ##STR16## wherein R.sup.1 is a hydrogen atom or a lower alkoxy group;
• R.sup.2 is a hydrogen atom, a lower alkyl group, a lower alkoxy group, a carboxyl group, an alkoxycarbonyl group, a carboxyalkyl group or an alkoxycarbonylalkyl group;
• R.sup.3 is a hydrogen atom, a carboxyl group, an alkoxycarbonyl group, a carboxyalkyl group, an alkoxycarbonylalkyl group, a carboxylalkoxy group or an alkoxycarbonylalkoxy group;
• R.sup.4 is a hydrogen atom, a hydroxyl group, a lower alkyl group or a lower alkoxy group;
• n is an integer of 0 to 4;
• A is an alkylene group having a carbon number of 1 to 4, which may have 1 or 2 substituents selected from the group consisting of hydroxyalkyl, carboxyl, alkoxycarbonyl, carboxyalkyl and alkoxycarxbonylalkyl;
• X is a single bond, an oxygen atom, a sulfur atom or a carbonyl group;
• Y is a saturated or unsaturated 5- or 6-membered monocylic heterocyclic moiety containing 1 to 2 heteroatoms selected from the group consisting of O and N, optionally having a substituent group;
• wherein the group represented by ##STR17## is a member selected from the group consisting of indolyl, benzofuranyl, benzothienyl, benzimidazolyl, benzoxazolyl, benzothiazolyl, naphthyl, tetrahydronaphthyl and indanyl;
• and said lower alkyl or alkoxy group has a carbon number of 1 to 6.