Derivatives of 7-alkynyl-1,8-naphthyridones, preparation method thereof and use of same in therapeutics

1. A compound of formula (I):

wherein:

R 1 and R 2 represent, independently of one another:

a hydrogen atom, or

a C 1 -C 7 alkyl group optionally substituted by one or more alkoxy groups;

R 3 represents a C 1 -C 7 alkyl group;

R 4 represents a hydrogen atom or a C 1 -C 4 alkyl group;

Y represents a C 1 -C 4 alkoxy group or an —NRR′ or —O(CH 2 ) n —C(O)—NRR′ group where R and R′ are as defined below and n is an integer equal to 1 or 2;

R″ represents a C 1 -C a alkyl group; and

R and R′ represent, independently of one another, a hydrogen atom, a —CO—(C 1 -C 4 alkyl) group or a —COOR″ group, where R″ is as defined above;

or an acid addition salt thereof, or an enantiomer or diastereoisomer thereof, or a mixture thereof.

2. The compound according to claim 1 , wherein Y represents a C 1 -C 4 -alkoxy group;

or an acid addition salt thereof, or an enantiomer or diastereoisomer thereof, or a mixture thereof.

3. The compound according to claim 1 , wherein Y represents an —NRR′ group where R and R′ are as defined in claim 1 ,

or an acid addition salt thereof, or an enantiomer or diastereoisomer thereof, or a mixture thereof.

4. The compound according to claim 1 , wherein Y represents an —O(CH 2 ) n —C(O)—NRR′ group where R and R′ are as defined in claim 1 and n is an integer equal to 1 or 2;

or an acid addition salt thereof, or an enantiomer or diastereoisomer thereof, or a mixture thereof.

5. The compound according to claim 1 , selected from the group consisting of:

(±)-2-amino-7-(3,4-dimethoxy-3-methylbut-1-yn-1-yl)-1-ethyl-N-methyl-4-oxo-1,4-dihydro-1,8-naphthyridine-3-carboxamide;

2-amino-7-[3-(2-amino-2-oxoethoxy)-3-methylbut-1-yn-1-yl]-1-ethyl-N-methyl-4-oxo-1,4-dihydro-1,8-naphthyridine-3-carboxamide; and

2-amino-1-ethyl-7-(3-methoxyprop-1-yn-1-yl)-N-methyl-4-oxo-1,4-dihydro-1,8-naphthyridine-3-carboxamide;

or an acid addition salt thereof.

6. A process for the preparation of a compound of formula (I) according to claim 1 , comprising reacting a compound of formula (VII):

wherein X is a halogen atom and R 3 and R 4 are as defined in claim 1 ,

with a compound of formula (VIII):

wherein Y, R 1 and R 2 are as defined in claim 1 .

7. A pharmaceutical composition comprising a compound of formula (I) according to claim 1 , or a pharmaceutically acceptable salt, or an enantiomer or a diastereoisomer or a mixture thereof, and also at least one pharmaceutically acceptable excipient.

8. A pharmaceutical composition comprising a compound according to claim 5 , or a pharmaceutically acceptable salt thereof, and also at least one pharmaceutically acceptable excipient.

9. The compound according to claim 1 wherein R 1 and R 2 are hydrogen, R 3 is ethyl, R 4 is methyl and Y is

or an acid addition salt thereof.

10. The compound according to claim 1 where R 1 , R 2 and R 4 is methyl, R 3 is ethyl and Y is NH 2 or an acid addition salt thereof.