Use of substituted 2-(diaza-bicyclo-alkyl)-pyrimidone derivatives for the treatment of neurodegenerative diseases

A method for the treatment of a disease selected from the group consisting of Alzheimer's disease, taupathies, non-insulin dependent diabetes, which comprises administering to a patient in need of said treatment a therapeutically effective amount of a compound of formula (I) or a pharmaceutically acceptable salt thereof:

• wherein:
• n represents 1 or 2;
• R1 represents a hydrogen atom, a C1-6 alkyl group or a halogen atom;
• R2 represents a hydrogen atom, a C1-6 alkyl group optionally substituted by 1 to 4 substituents selected from a halogen atom, a hydroxyl group, a C1-4 alkoxy group;
• a C1-2 perhalogenated alkyl group, a benzyl group, a phenethyl group, a benzyloxycarbonyl group, a C1-4 alkoxy carbonyl group, a benzene ring, a naphthalene ring, a quinoline ring, a phthalazine ring, a 5,6,7,8-tetrahydronaphthalene ring, a pyridine ring, an indole ring, a pyrrole ring, a thiophene ring, a benzenesulfonyl group, a benzoyl group, a pyridazine ring, a furan ring and an imidazole ring;
• each of the benzyl group, the phenethyl group, the benzyloxycarbonyl group, the benzenesulfonyl group, the benzoyl group and the benzene, naplithalene, quinoline, phthalazine, 5,6,7,8-tetrehydronaphthalene, pyridine, indole, pyrrole and thiophene rings being optionally substituted by 1 to 4 substituents selected from a C1-6 alkyl group, a benzene ring, a halogen atom, a C1-2 perhalogenated alkyl group, a C1-3 halogenated alkyl group, a hydroxyl group, a C1-4 alkoxy group, a nitro group, a cyano group, an amino group, a C1-6 monoalkylamino group and a C2-10 dialkylamino group;
• R3 represents a 2, 4 or 5-pyrimidine ring or a 2,3 or 4-pyridine ring, the rings being optionally substituted by a C1-4 alkyl group, C1-4 alkoxy group or a halogen atom;
• and
• R4 represents a C1-4 alkyl group optionally substituted by a hydroxyl group, a C1-4 alkoxy group or a halogen atom.