Pyridazinone derivatives and processes for preparing the same

Abstract

Disclosed are a pyridazinone compound represented by the formula: ##STR1## wherein (1) R.sup.1 is a substituted or unsubstituted C.sub.1-10 alkyl, a C.sub.3-6 cycloalkyl, a lower alkenyl, a heterocyclic group having N, O or S atom or camphor-10-yl; R.sup.3 is hydrogen, a substituted or unsubstituted lower alkyl or a lower alkenyl; or R.sup.1 and R.sup.3 are bonded at terminal ends thereof to form a lower alkylene; and Z is a group represented by the formula: ##STR2## where n is 1 or 2; and D is hydrogen or a halogen; or (2) R.sup.1 is a substituted or unsubstituted C.sub.1-10 alkyl, a substituted or unsubstituted phenyl, a C.sub.3-6 cycloalkyl, a lower alkenyl, a heterocyclic group having N, O or S atom or camphor-10-yl; R.sup.3 is hydrogen, a substituted or unsubstituted lower alkyl or a lower alkenyl; or R.sup.1 and R.sup.3 are bonded at terminal ends thereof to form a lower alkylene; and Z is a group represented by the formula: ##STR3## and R.sup.2 is hydrogen, a substituted or unsubstituted lower alkyl, an aryl or a lower alkenyl; and --A--B-- is an ethylene or vinylene each of which may be substituted by 1 or 2 groups selected from the group consisting of a lower alkyl and phenyl group, or a pharmaceutically acceptable salt thereof, and processes for preparing the same.