Abstract: There is disclosed an aminobenzenesulfonic acid derivative of the formula: ##STR1## wherein R.sub.1 represents hydrogen atom, a C.sub.1 -C.sub.6 alkyl group, a C.sub.3 -C.sub.7 cycloalkyl group, a C.sub.1 -C.sub.4 halogenated alkyl group, a halogen atom or a C.sub.6 -C.sub.12 aryl group, R.sub.2 represents hydrogen atom, a C.sub.1 -C.sub.6 alkyl group or a C.sub.7 -C.sub.12 aralkyl group which may have at least one substituent selected from cyano group, nitro group, C.sub.1 -C.sub.6 alkoxy groups, halogen atoms, C.sub.1 -C.sub.6 alkyl groups and amino groups, and n represents an integer of 1 to 4, of a pharmaceutically acceptable salt thereof.

Abstract: There are provided novel pyridazinone derivatives having the general formula (I): ##STR1## wherein A represents 5- or 6-membered heterocyclic ring having 1-3 nitrogen atoms, which may be substituted by at least one member selected from the group consisting of C.sub.1-5 alkyl, cyano, hydroxyl, C.sub.1-5 alkoxyl, amino, C.sub.1-5 alkylamino, C.sub.2-6 dialkylamino, C.sub.2-5 acylamino, carboxyl, C.sub.2-5 alkoxycarbonyl and carbamoyl, and R.sup.1 and R.sup.2 independently represent hydrogen atom or C.sub.1-5 alkyl or R.sup.1 and R.sup.2 may form together C.sub.1-5 alkylene, and salts thereof.

Abstract: Pyridazinone derivatives represented by the following general formula (I): ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 represent a hydrogen atom, hydroxy group or alkoxy group of not more than 5 carbon atoms, or two of R.sub.1, R.sub.2 and R.sub.3 may be combined together to form a group of --O--CH.sub.2 --O-- or --O--CH.sub.2 --CH.sub.2 --O--, R.sub.4 represents an alkyl group, n represents an integer of 0 to 4 and the dotted line represents a single or double bond, or salts thereof.

Abstract: There are provided novel pyridazinone derivatives having the general formula (I): ##STR1## wherein A represents 5- or 6-membered heterocyclic ring having 1-3 nitrogen atoms, which may be substituted by at least one member selected from the group consisting of C.sub.1-5 alkyl, cyano, hydroxyl, C.sub.1-5 alkoxy, amino, C.sub.1-5 alkylamino, C.sub.2-6 dialkylamino, C.sub.2-5 acylamino, carboxyl, C.sub.2-5 alkoxycarbonyl and carbamoyl, and R.sup.1 and R.sup.2 independently represent hydrogen atom or C.sub.1-5 alkyl or R.sup.1 and R.sup.2 may form together C.sub.1-5 alkylene, and salts thereof.

Abstract: Caroverine fumarate has an inhibitory effect on platelet aggregation, and exhibits the beneficial effect of increasing coronary blood flow, especially in coronary arteries, and thus is specifically suitable in applications for ischemic heart diseases.