Pyrazolo[3,4-c]pyridine derivatives

A compound of formula (I), a tautomer thereof, or an optical isomer thereof, or a pharmaceutically acceptable salt thereof:

• wherein
• X is selected from CH and N;
• Z is selected from
• RNa and RNb are each independently selected from hydrogen, C1-6alkyl, C2-6alkenyl, C2-6alkynyl, C1-6alkoxy-C0-6alkyl, (C0-6alkyl)(C0-6alkyl)N—C1-6alkyl, (C2-6alkylene)N—C1-6 alkyl or carbamoyl-C1-6alkyl;
• or
• RNa and RNb, together with the atoms attached thereto, form a 5, 6 or 7-membered cyclic moiety,
• wherein
• the 5, 6 or 7-membered cyclic moiety is substituted by one RNg, wherein the RNg is selected from hydrogen, C1-4alkyl, hydroxyl, C1-4alkoxy, halogen, oxo and amino,
• the 5, 6 or 7-membered cyclic moiety, besides the N atom attaching to RNb comprises 0, 1, 2, 3 or 4 heteroatoms selected from N, O and S,
• the 5, 6 or 7-membered cyclic moiety comprises 0, 1, 2 or 3 double bonds;
• RNc is selected from hydrogen, C1-6alkyl and C1-6alkoxy;
• RNd is selected from hydrogen, C1-6alkoxy, halogen-substituted C1-6alkoxy, carbamoyl-C1-6alkyl and C1-6alkoxy-C1-6alkyl;
• RNe is selected from hydrogen, halogen, C1-6alkoxy, halogen-substituted C1-6alkoxy, carbamoyl-C1-6alkyl and C1-6alkoxy-C1-6alkyl;
• RNf is selected from hydrogen, halogen, C1-6alkoxy, halogen-substituted C1-6alkoxy, carbamoyl-C1-6alkyl and C1-6alkoxy-C1-6alkyl;
• with the proviso that the compound of formula (I) does not comprise the following compounds:
• 1-(4-methoxyphenyl)-7-oxo-6-(4-(2-oxopiperidin-1-yl)phenyl)-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine-3-carboxamide
• 1-(4-methoxyphenyl)-7-oxo-6-(4-(2-oxopyridin-1(2H)-yl)phenyl)-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine-3-carboxamide
• 1-(3-chlorophenyl)-7-oxo-6-(4-(2-oxopiperidin-1-yl)phenyl)-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine-3-carboxamide
• 1-(3-chlorophenyl)-7-oxo-6-(4-(2-oxopyridin-1(2H)-yl)phenyl)-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine-3-carboxamide
• 1-(4-methoxyphenyl)-7-oxo-6-(4-(2-oxopiperazin-1-yl)phenyl)-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine-3-carboxamide