Piperazinyl-pyridine derivatives

A compound of the formula I:

• wherein:
• R is hydrogen or lower alkyl;
• R1 is selected from the group consisting of hydrogen, lower alkyl, C3-C7-alkenyl, C3-C7-alkinyl, lower halogenalkyl, lower hydroxyalkyl, lower alkoxyalkyl,
• C3-C7-cycloalkyl and lower C3-C7-cycloalkylalkyl;
• X is N and Y is C, or
• Y is N and X is C;
• m is 0 or 1;
• Z is C(O) or SO2;
• R2 is selected from the group consisting of lower alkyl, C3-C7-alkenyl, C3-C7-alkinyl, lower halogenalkyl, lower hydroxyalkyl, lower alkoxyalkyl,
• C3-C7-cycloalkyl or C3-C7-cycloalkyl substituted by phenyl or lower alkyl,
• lower C3-C7-cycloalkylalkyl,
• unsubstituted phenyl or phenyl mono- or disubstituted by lower alkyl, lower alkoxy, halogen or lower halogenalkyl,
• lower phenylalkyl wherein the phenyl ring is unsubstituted or mono- or disubstituted by lower alkyl, lower alkoxy, halogen or lower halogenalkyl,
• unsubstituted pyridyl or pyridyl mono- or disubstituted by lower alkyl, lower alkoxy, halogen or lower halogenalkyl, and
• —NR3R4,
• or, in case Z is C(O), R2 can also be lower alkoxy or lower alkoxyalkoxy;
• R3 is hydrogen or lower alkyl;
• R4 is selected from the group consisting of
• lower alkyl, C3-C7-alkenyl, C3-C7-alkinyl,
• lower alkoxyalkyl,
• C3-C7-cycloalkyl, C3-C7-cycloalkyl substituted by phenyl,
• lower C3-C7-cycloalkylalkyl,
• unsubstituted phenyl or phenyl mono- or disubstituted by lower alkyl, lower alkoxy, halogen or lower halogenalkyl, or
• lower phenylalkyl wherein phenyl is unsubstituted or mono- or disubstituted by lower alkyl, lower alkoxy, halogen or lower halogenalkyl;
• or
• R3 and R4 together with the nitrogen atom to which they are attached form a 4-, 5-, 6- or 7-membered heterocyclic ring optionally containing a further heteroatom selected from nitrogen, oxygen or sulfur, said heterocyclic ring being unsubstituted or substituted by one, two or three groups independently selected from lower alkyl, lower alkoxy, oxo, halogen and halogenalkyl, or being condensed with a phenyl or cyclohexyl ring, said phenyl or cyclohexyl ring being unsubstituted or substituted by one, two or three groups independently selected from lower alkyl, lower alkoxy, halogen and halogenalkyl;
• and pharmaceutically acceptable salts thereof.