Abstract: The invention relates to pyrimidone derivative represented by formula (I) or a salt thereof wherein X represents hydrogen atoms, a sulfur atom, an oxygen atom or a C1-2 alkyl group and a hydrogen atom; Y represents a bond, an ethenylene group, an ethynylene group, a 1,2-cyclopropylene, an oxygen atom, a sulfur atom, a sulfonyl group, a sulfoxyde group, a carbonyl group, a nitrogen atom being optionally substituted; or a methylene group optionally substituted; R1 represent a 2,3 or 4-pyridyl group optionally substituted by a C3-6cycloalkyl group a C1-4alkyl group, a C1-4alkoxy group, a benzyl group or a halogen atom; when Y represents a bond, a methylene group optionally substituted or a carbonyl group then R2 represent a C1-16alkyl group, a C3-6cycloalkyl group, a C1-4alkylthio group, a C1-4alkoxy group, a C1-2perhalogenated alkyl group, a C1-3halogenated alkyl group, a 5,6,7,8-tetrahydronaphthyl ring, a naphthyl ring, a phenylthio group, a benzyl group, a phenyl ring, a pyridyl ring, an indole ring, a pyrrol

Abstract: The invention relates to an imidazo[1,2-a]pyrimidone derivative represented by formula (1) or a salt thereof, wherein: X represents a bond, an ethenylene group, and ethenylene group, a methylene group optionally substituted by one or two groups selected from a C1-6 alkyl group, a hydroxy group and a C1-4 alkoxy group; a carbonyl group, an oxygen atom, a sulfur atom, a sulfonyl group, a sulfoxide group or a nitrogen atom being optionally substituted by a C1-6 alkyl group; R1 represents a 2,3 or 4-pyridyl group optionally substituted by a C1-4 alkyl group, C1-4 alkoxy group or a halogen atom; R2 represents a C1-4 alkyl group, perhalogenated alkyl group, a C1-3 halogenated alkyl group, a benzyl group, a phenyl ring, a naphthyl ring, 5,6,7,8-tetrahydronaphthyl ring, a pyridyl ring, an indole ring, a pyrrole ring, a thiophene ring, a furan ring or an imidazole ring, the benzyl group and the rings being optionally substituted by 1 to 4 substituents selected from a C1-4 alkyl group, a phenyl ring, a haloge