Compounds according to formula I wherein R1 represents hydrogen, halogen or one or more straight or branched, saturated or unsaturated C1-6 hydrocarbon radical, optionally substituted with halogen, hydroxy, cyano, nitro, carboxy, alkoxy, alkoxycarbonyl, alkylcarbonyl, formyl, amino, aminoalkyl, aminocarbonyl, alkylcarbonylamino, sulfo, aminosulfonyl, alkylsulfonylamino, hydroxysulfonyloxy, dihydroxyphosphinoyloxy or phosphono; X represents a straight or branched, saturated or unsaturated C1-12 hydrocarbon diradical, optionaly substituted with halogen, hydroxy, cyano, nitro, carboxy, alkoxy, alkoxycarbonyl, alkylcarbonyl, formyl, amino, aminoalkyl, aminocarbonyl, alkylcarbonylamino, sulfo, aminosulfonyl, alkylsulfonylamino, hydroxysulfonyloxy, dihydroxyphosphinoyloxy or phosphono; Y represents a bond, 0, C(O), S, S(O), S(0)2, C(O)O, NH, C(O)NH, OC(O) or NHC(O); Z represents an aromatic or non-aromatic heterocyclic radical with 5-12 ring atoms, optionally substituted with halogen, hydroxy, cyano, nitro, alkoxy, alkoxycarbonyl, alkylcarbonyl, formyl, aminoalkyl or straight or branched, saturated or unsaturated C1-4 hydrocarbon radical, optionally substituted with halogen, hydroxy, cyano, nitro, alkoxy, alkoxycarbonyl, alkylcarbonyl, formyl or aminoalkyl; provided that R1 is not attached to the nitrogen-atom in the pyridyl ring; and pharmaceutically acceptable salts, solvates, hydrates, N-oxides and prodrugs thereof are disclosed. The compounds are useful in therapy.