Piperidine compounds

A compound selected from those of formula (I):

• wherein:
• W represents:
• either naphthyl optionally substituted by one or more identical or different groups selected from halogen, linear or branched (C1-C6)alkyl, hydroxy, linear or branched (C1-C6)alkoxy, cyano, nitro, linear or branched trihalo(C1-C6)alkyl, methylenedioxy, and ethylenedioxy,
• or a group of formula Y where:
• wherein E, together with a carbon of the phenyl to which it is bonded, represents an unsaturated, partially saturated, or aromatic monocyclic ring having 5 to 6 ring members and having one or two hetero atoms selected from oxygen or nitrogen, it being possible for the group Y to be bonded to the (CH2)n group of the compounds of formula (I), either by the phenyl, or by the monocyclic ring E, and for each of the Y groups to be optionally substituted by one or more identical or different groups selected from halogen, hydroxy, cyano, nitro, oxo, linear or branched (C1-C6)alkyl, linear or branched (C1-C6)alkoxy, linear or branched trihalo(C1-C6)alkyl, heterocycloalkylalkylene in which alkylene has 1 to 6 carbon atoms and may be linear or branched (and in which the heterocyclic moiety has 5 ring members and two or three nitrogen atoms), provided that when Y is substituted by oxo, then E, together with the carbon of the phenyl to which it is bonded, represents a monocyclic ring having 5 ring members, and having two identical or different hetero atoms selected from oxygen or nitrogen,
• n represents an integer from 1 to 6 inclusive,
• Z represents a single bond, oxygen, or nitrogen substituted by a group selected from hydrogen, linear or branched (C1-C6)alkyl (itself optionally substituted by one or more hydroxy groups) and aryl-(C1-C6)alkyl in which alkyl may be linear or branched,
• A represents CH or nitrogen,
• Q represents CH or nitrogen, it being understood that one of the groups A and Q represents nitrogen and the other one represents CH, and that A represents nitrogen when Z represents a single bond, and
• M, together with the carbon of the pyridinyl to which it is bonded, represents thieno, furo, pyrrolo or oxopyrrolo, which are fused [3,2-c] or [2,3-c] with the pyridinyl,
• its optical isomers and pharmaceutically-acceptable acid or base addition salts thereof,
• it being understood that “aryl” is phenyl, naphthyl, dihydronaphthyl, or tetrahydronaphthyl.