2-(1-heteroarylpiperazin-4-yl)methyl-1,4-benzodioxane derivatives as alpha2c antagonists

A compound of formula I,

• wherein
• ring A is a five membered unsaturated heterocyclic ring containing 1, 2, or 3 ring heteroatom(s) each independently selected from N, O, and S, wherein said heterocyclic ring is unsubstituted, or said heterocyclic ring is substituted with 1 substituent R1, or said heterocyclic ring is substituted with 2 substituents R1 and R2, or said heterocyclic ring is substituted with 3 substituents R1, R2, and R3, or said heterocyclic ring is substituted with 4 substituents R1, R2, R3, and R4;
• R1 is (C1-C6)alkyl, (C1-C6)alkoxy, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl, (C1-C6)alkoxy-(C═O)—, CN, (C1-C6)alkyl-(C═O)—, R5R6N—, R5R6N—(C═O)—, R6(C═O)—R5N—, heterocyclyl, heterocyclyl-N—, or phenyl-N—, wherein said heterocyclyl or phenyl is optionally substituted with 1, 2, 3, or 4 substituent(s) each independently being (C1-C6)alkyl, (C1-C6)alkoxy, oxo, or phenyl(C1-C6)alkoxy;
• R2 is (C1-C6)alkyl, (C1-C6)alkoxy, or (C1-C6)alkoxy(C1-C6)alkyl;
• R3 is (C1-C6)alkyl, (C1-C6)alkoxy, or (C1-C6)alkoxy(C1-C6)alkyl;
• R4 is (C1-C6)alkyl;
• R5 is H, or (C1-C6)alkyl;
• and
• R6 is H, or (C1-C6)alkyl;
• or R1 and R2 form, together with the ring atoms to which they are attached, a condensed 6 membered unsaturated heterocyclic ring, containing 1 or 2 heteroatom(s) being N;
• or a pharmaceutically acceptable salt or ester thereof;
• with the proviso that A is not 1,2,3-oxadiazol-3-ium-3-yl.