Pyrazolo [3,4-d] pyrimidine derivatives useful to treat respiratory disorders

A compound of formula (I)

• or a pharmaceutically acceptable salt, wherein:
• R1 is C1-C3-alkyl;
• R2 is phenyl having the substitution pattern,
• wherein the R2 phenyl is optionally fused at R4-R5, R5-R6, R6-R7 or R7-R8 by a further phenyl, a 5-6 membered heteroaryl group, a C4-C6 carbocyclic group or a 5-6 membered heterocyclyl group, where the 5-6 membered heteroaryl or fused 5-6 membered heteroaryl, phenyl or the fused phenyl group is independently optionally substituted by one or more groups selected from List X;
• List X represents hydroxyl, cyano, nitro, C1-C8-alkyl, C1-C8-alkenyl, C1-C8-alkynyl, C1-C8-alkoxy, C1-C8-alkenyloxy, C1-C8-alkynyloxy, phenyl, a 5-6 membered heteroaryl group, a C4-C6 carbocyclic group or a 5-6 membered heterocyclyl group, —(C0-C4 alkylene)-O—(C1-C4 alkylene)-R9, (C0-C4 alkylene)-O—(C2-C4 alkylene)-R10, (C0-C4 alkylene)-N(R11)—(C1-C4 alkylene)-R12, —(C0-C4 alkylene)-N(R13)—(C2-C4 alkylene)-R14, halogen, formyl, C1-C8-alkylcarbonyl, carboxy, C1-C8-alkoxycarbonyl, C1-C8-alkylaminooxycarbonyl, di-C1-C8-alkylaminooxycarbonyl, amino, C1-C8-alkylamino, di-C1-C8-alkylamino, C1-C8-alkylamidino, —N(H)C(═NH)C1-C8-alkyl, —N(C1-C8-alkyl)C(═NH)C1-C8-alkyl, C1-C8-alkylaminocarbonyl, di-C1-C8-alkylaminocarbonyl, aminocarbonylamino, aminocarbonyl(C1-C8-alkyl)amino, C1-C8-alkylaminocarbonylamino, di-C1-C8-alkylaminocarbonylamino, C1-C8-alkylaminocarbonyl(C1-C8-alkyl)amino, di-C1-C8-alkylaminocarbonyl(C1-C8-alkyl)amino, C1-C8-alkylcarbonylamino, C1-C8-alkylcarbonyl(C1-C8-alkyl)amino, C1-C8-alkylthiocarbonylamino, C1-C8-alkylthiocarbonyl(C1-C8-alkyl)amino, hydroxysulfonyl, C1-C8-alkylsulfonylamino, C1-C8-thioalkyl, C1-C8-alkylsulfinyl, C1-C8-alkylsulfonyl, aminosulfonyl, C1-C8-alkylaminosulfonyl or di-C1-C8-alkylaminosulfonyl, where each of the afore-mentioned hydrocarbon groups may be optionally substituted, where chemically feasible, by one or more halogen, hydroxyl, amino, C1-C4-alkylamino, di-C1-C4-alkylamino or C1-C4-alkoxy groups and where said cyclic groups may be optionally substituted by one or more hydroxyl, cyano, nitro, C1-C8-alkyl, C1-C8-alkenyl, C1-C8-alkynyl, C1-C8-alkoxy, C1-C8-alkenyloxy, C1-C8-alkynyloxy, halogen, C1-C8-alkylcarbonyl, carboxy, C1-C8-alkoxycarbonyl, amino, C1-C8-alkylamino, di-C1-C8-alkylamino, C1-C8-alkylaminocarbonyl, di-C1-C8-alkylaminocarbonyl, C1-C8-alkylcarbonylamino, C1-C8-alkylcarbonyl(C1-C8-alkyl)amino, C1-C8-alkylsulfonylamino, C1-C8-thioalkyl, C1-C8-alkylsulfinyl, C1-C8-alkylsulfonyl, aminosulfonyl, C1-C8-alkylaminosulfonyl or di-C1-C8-alkylaminosulfonyl groups;
• R9 and R12 independently represent hydrogen, C1-C4-alkenyl, C1-C4-alkynyl, halogen, cyano, nitro, C1-C8-alkylcarbonyl, carboxy, C1-C8-alkoxycarbonyl, C1-C8-thioalkyl, C1-C8-alkylsulfinyl, C1-C8-alkylsulfonyl, aminosulfonyl, C1-C8-alkylaminosulfonyl, di-C1-C8-alkylaminosulfonyl, phenyl, a C-linked 5-6 membered heteroaryl group, a C4-C6 carbocyclic group or a C-linked 5-6 membered heterocyclyl group, where said phenyl or cyclic groups may be optionally substituted by one or more hydroxyl, cyano, nitro, C1-C8-alkyl, C1-C8-alkenyl, C1-C8-alkynyl, C1-C8-alkoxy, C1-C8-alkenyloxy, C1-C8-alkynyloxy, halogen, C1-C8-alkylcarbonyl, carboxy, C1-C8-alkoxycarbonyl, amino, C1-C8-alkylamino, di-C1-C8-alkylamino, C1-C8-alkylaminocarbonyl, di-C1-C8-alkylaminocarbonyl, C1-C8-alkylcarbonylamino, C1-C8-alkylcarbonyl(C1-C8-alkyl)amino, C1-C8-alkylsulfonylamino, C1-C8-thioalkyl, C1-C8-alkylsulfinyl, C1-C8-alkylsulfonyl, aminosulfonyl, C1-C8-alkylaminosulfonyl or di-C1-C8-alkylaminosulfonyl groups;
• R10 and R14 independently represent hydroxyl, C1-C4-alkoxy, C1-C4-alkenyloxy, C1-C4-alkynyloxy, amino, C1-C8-alkylamino, di-C1-C8-alkylamino, C1-C8-alkylaminocarbonyl, di-C1-C8-alkylaminocarbonyl, C1-C8-alkylcarbonylamino, C1-C8-alkylcarbonyl(C1-C8-alkyl)amino, C1-C8-alkylsulfonylamino, an N-linked 5-6 membered heteroaryl group or an N-linked 5-6 membered heterocycly where said cyclic groups may be optionally substituted by one or more hydroxyl, nitro, C1-C8-alkyl, C1-C8-alkenyl, C1-C8-alkynyl, C1-C8-alkoxy, C1-C8-alkenyloxy, C1-C8-alkynyloxy, halogen, C1-C8-alkylcarbonyl, carboxy, C1-C8-alkoxycarbonyl, amino, C1-C8-alkylamino, di-C1-C8-alkylamino, C1-C8-alkylaminocarbonyl, di-C1-C8-alkylaminocarbonyl, C1-C8-alkylcarbonylamino, C1-C8-alkylcarbonyl(C1-C8-alkyl)amino, C1-C8-alkylsulfonylamino, C1-C8-thioalkyl, C1-C8-alkylsulfinyl, C1-C8-alkylsulfonyl, aminosulfonyl, C1-C8-alkylaminosulfonyl or di-C1-C8-alkylaminosulfonyl groups;
• R11 and R13 independently represent hydrogen or C1-C6-alkyl;
• R3 is hydrogen;
• Y represents the group —N(R15)R16;
• and
• R15 and R16 independently represent hydrogen or C1-C4-alkyl.