Novel substituted bipyridine derivatives and their use as adenosine receptor ligands

A compound of formula (I)

• wherein
• one of the two ring members X and Y represents N and the other represents C—R6, where
• R6 represents hydrogen or (C1-C4)-alkyl,
• Z represents N—R7 or O, where
• R7 represents hydrogen or (C1-C4)-alkyl which may be substituted by hydroxyl or (C1-C4)-alkoxy,
• R1 and R2 are identical or different and independently of one another represent hydrogen or (C1-C6)-alkyl which may be mono- or disubstituted by identical or different substituents from a group consisting of hydroxyl, (C1-C4)-alkoxy, amino, mono-(C1-C4)-alkylamino, di-(C1-C4)-alkylamino, carboxyl, (C1-C4)-alkoxycarbonyl and a 4- to 7-membered heterocycle,
• where the heterocycle mentioned contains one or two ring heteroatoms from the group consisting of N, O and S and for its part may be mono- or disubstituted by identical or different substituents from the group consisting of (C1-C4)-alkyl, hydroxyl, oxo and (C1-C4)-alkoxy,
• or
• R1 and R2 together with the nitrogen atom to which they are attached form a 4- to 7-membered heterocycle which may contain a further ring heteroatom from the group consisting of N, O and S and which may be mono- or disubstituted by identical or different substituents from the group consisting of (C1-C4)-alkyl, hydroxyl, oxo and (C1-C4)-alkoxy,
• R3 represents hydrogen or (C1-C6)-alkyl which may be mono- or disubstituted by identical or different substituents from the group consisting of (C3-C6)-cycloalkyl, oxo, hydroxyl, (C1-C4)-alkoxy, carboxyl, amino, mono-(C1-C4)-alkylamino and di-(C1-C4)-alkylamino, or represents (C4-C6)-cycloalkyl,
• where the cycloalkyl radicals mentioned for their part may be substituted up to two times by identical or different substituents from the group consisting of (C1-C4)-alkyl, hydroxyl, oxo and (C1-C4)-alkoxy and where in these cycloalkyl radicals a ring CH2-group may be replaced by an oxygen atom,
• R4 represents hydrogen, halogen, (C1-C4)-alkyl or (C1-C4)-alkoxy, where alkyl and alkoxy may each be substituted up to three times by fluorine,
• and
• R5 represents 5 to 10-membered heteroaryl having up to three ring heteroatoms from the group consisting of N, O and S, which may in each case
• (i) be mono- or disubstituted by identical or different substituents from the group consisting of halogen, nitro, cyano, (C1-C6)-alkyl, phenyl, hydroxyl, (C1-C6)-alkoxy, amino, mono-(C1-C6)-alkylamino, mono-(C2-C6)-alkenylamino and di-(C1-C6)-alkylamino
• and/or
• (ii) be substituted by pyrrolidino, piperidino, morpholino, piperazino, N′—(C1-C4)-alkylpiperazino or a group of the formula -L-R8, where
• L represents a bond, NH or O
• and
• R8 represents phenyl or 5- or 6-membered heteroaryl having up to three ring heteroatoms from the group consisting of N, O and S, each of which may be mono- to trisubstituted by identical or different substituents from the group consisting of halogen, nitro, cyano, (C1-C6)-alkyl, trifluoromethyl, hydroxyl, (C1-C6)-alkoxy, difluoromethoxy, trifluoromethoxy, amino, mono-(C1-C6)-alkylamino, di-(C1-C6)-alkylamino, (C1-C6)-alkoxycarbonyl and carboxyl,
• or a salt thereof.