5-PHENYL-3-PYRIDAZINONE DERIVATIVES AND DRUG COMPOSITIONS CONTAINING THE SAME

摘要

A 5-phenyl-3-pyridazinone derivative having the formula (I) <CHEM> wherein R1 represents an unsubstituted or substituted C1 to C8 alkyl group, C3 to C7 cycloalkyl group, or indanyl group; R2 represents a C1 to C4 alkyl group, R3 represents a hydrogen atom or an unsubstituted or substituted C1 to C5 alkyl group; a C3 to C7 cycloalkyl group; or an aryl group which may contain a heteroatom; R4 and R5 independently represent a hydrogen atom, C1 to C6 alkyl group, an unsubstituted or substituted phenyl, or a monocyclic aryl group which may contain a heteroatom; a dotted line represents a single or double bond, provided that when the dotted line represents a single bond; R6 represents a hydrogen atom or C1 to C6 alkyl group.