Piperazine derivatives

1. A compound of general formula (I)

in which:—

R 0 represents phenyl or 4-fluorophenyl; and

R 1 represents:—

(i) a group of formula

R 2 —(CH 2 ) n CH 2 —

wherein:

n is 1 or 2; and

R 2 represents a phenyl group that is substituted by one fluorine atom or phenyl substituted by one, two, or three substituents selected independently from (1-2C)alkylenedioxy, a hydroxyl group, a (1-4C) alkyl group, a (3-6C)cycloalkyl group, and a halo(1-4C) alkyl group; or

(ii) a group of formula

R 3 —(CH 2 ) m C(R 4a R 4b )—

wherein:

m is 1 or 2; and

R 3 represents a phenyl group that is unsubstituted or substituted by one, two or three substituents selected independently from (1-2C)alkylenedioxy, a halogen atom, a hydroxyl group, a (1-4C) alkyl group, a (3-6C)cycloalkyl group, a halo(1-4C) alkyl group, a (1-4C)alkoxy group and a halo(1-4C)alkoxy group; and

one or two of R 4a and R 4b represents a (1-4C) alkyl or a (1-4C)alkoxy(1-4C)alkyl group and any remainder represents a hydrogen atom; or

(iii) indan-1-yl, indan-2-yl, 1,2,3,4-tetrahydronaphth-1-yl or 1,2,3,4-tetrahydronaphth-2-yl, each of which may bear a hydroxyl substituent on a non-aromatic carbon atom; or (3-6C) cycloalkyl;

or a pharmaceutically acceptable salt thereof.

2. A compound of general formula (I)

in which:—

R 0 represents phenyl or 4-fluorophenyl; and

R 1 represents indan-1-yl, indan-2-yl, 1,2,3,4-tetrahydronaphth-1-yl, or 1,2,3,4-tetrahydronaphth-2-yl, each of which may bear a hydroxyl substituent on a non-aromatic carbon atom; or (3-6C) cycloalkyl.

3. A compound according to claim 2 , in which R 1 represents indan-1-yl.

4. A compound according to claim 3 selected from the group consisting of

1(R)-Indan-1-yl-4-(3-phenylpropyl)piperazine;

1(S)-Indan-1-yl-4-(3-phenylpropyl)piperazine ;

1-(1R, 2S)-(2-Hydroxyindan-1-yl)-4-(3-phenylpropyl)piperazine;

1-(1S, 2R)-(2-Hydroxyindan-1-yl)-4-(3-phenylpropyl)piperazine; and pharmaceutically acceptable salts thereof.

5. A compound according to claim 4 in the form of a dihydrochloride salt.

6. A compound according to claim 3 which is 1(R)-Indan-1-yl-4-(3-phenylpropyl)piperazine dihydrochloride.

7. A compound according to claim 2 in which R 1 represents indan-2-yl.

8. A compound according to claim 7 which is 1(R)-Indan-2-yl-4-(3-phenylpropyl)piperazine, 1(S)-Indan-2-yl-4-(3-phenylpropyl)piperazine, or a pharmaceutically acceptable salt thereof.

9. A pharmaceutical composition, which comprises a therapeutically effective amount of a compound of general formula (I)

in which:—

R 0 represents phenyl or 4-fluorophenyl; and

R 1 represents:—

(i) a group of formula

R 2 —(CH 2 ) n CH 2 —

wherein:

n is 1 or 2; and

R 2 represents a phenyl group that is substituted by one fluorine atom or phenyl substituted by one, two, or three substituents selected independently from (1-2C)alkylenedioxy, a hydroxyl group, a (1-4C) alkyl group, a (3-6C)cycloalkyl group, and a halo(1-4C) alkyl group; or

(ii) a group of formula

R 3 —(CH 2 ) m C(R 4a R 4b )—

wherein:

m is 1 or 2; and

R 3 represents a phenyl group that is unsubstituted or substituted by one, two or three substituents selected independently from (1-2C)alkylenedioxy, a halogen atom, a hydroxyl group, a (1-4C) alkyl group, a (3-6C)cycloalkyl group, a halo(1-4C) alkyl group, a (1-4C)alkoxy group and a halo(1-4C)alkoxy group; and

one or two of R 4a and R 4b represents a (1-4C) alkyl or a (1-4C)alkoxy(1-4C)alkyl group and any remainder represents a hydrogen atom; or

(iii) indan-1-yl, indan-2-yl, 1,2,3,4-tetrahydronaphth-1-yl or 1,2,3,4-tetrahydronaphth-2-yl, each of which may bear a hydroxyl substituent on a non-aromatic carbon atom; or (3-6C) cycloalkyl;

or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable diluent or carrier.

10. A pharmaceutical composition, which comprises a compound of general formula (I)

in which:—

R 0 represents phenyl or 4-fluorophenyl; and

R 1 represents indan-1-yl, indan-2-yl, 1,2,3,4-tetrahydronaphth-1-yl, or 1,2,3,4-tetrahydronaphth-2-yl, each of which may bear a hydroxyl substituent on a non-aromatic carbon atom; or (3-6C) cycloalkyl,

or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable diluent or carrier.

11. The pharmaceutical composition according to claim 10 , in which in the compound of general formula (I) R 1 represents indan-1-yl or indan-2-yl.

12. The pharmaceutical composition according to claim 10 , in which in the compound of general formula (I) is selected from 1(R)-Indan-1-yl-4-(3-phenylpropyl)piperazine;

1(S)-Indan-1-yl-4-(3-phenylpropyl)piperazine;

1-(1R, 2S)-(2-Hydroxyindan-1-yl)-4-(3-phenylpropyl)piperazine;

1-(1S, 2R)-(2-Hydroxyindan-1-yl)-4-(3-phenylpropyl)piperazine; and pharmaceutically acceptable salts thereof, in combination with a pharmaceutically acceptable diluent or carrier.

13. The pharmaceutical composition according to claim 10 , in which in the compound of general formula (I) is selected from 1(R)-Indan-2-yl-4-(3-phenylpropyl)piperazine, 1(S)-Indan-2-yl-4-(3-phenylpropyl)piperazine, and a pharmaceutically acceptable salt thereof, in combination with a pharmaceutically acceptable diluent or carrier.