Bipyridine sulfonamide derivatives for the treatment of neurodegenerative diseases or conditions

A compound of Formula (I):

• wherein
• R1 is selected from hydrogen, optionally substituted C1-C6 alkyl, halogen, nitro and amino;
• R2 is selected from hydrogen, optionally substituted heterocycloalkylalkyl, optionally substituted heteroarylalkyl, optionally substituted —(SO2)-thiophene and optionally substituted C1-C6 alkyl;
• R3 is selected from optionally substituted aryl, optionally substituted arylalkyl, optionally substituted heteroaryl, optionally substituted heterocycloalkyl, optionally substituted C1-C6 alkyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkylalkyl, optionally substituted heteroarylalkyl, cyano, ethenyl and —N(R7)(R8), wherein R7 and R8 are independently selected from hydrogen or substituted or unsubstituted alkyl, and when R7 and R8 are substituted or unsubstituted alkyl, they may together form a heterocycloalkyl, containing five to seven members with the nitrogen atom and may intracyclically contain one or more further heteroatoms selected from nitrogen, oxygen and sulphur;
• R4 is selected from —O—R5, wherein R5 is optionally substituted C1-C6 alkyl, or —SO2—R6, wherein R6 is C1-C6 alkyl;
• A1, A2, A3, A4, A5, A6 are independently selected from hydrogen and C1-C6 alkyl;
• or a tautomer, salt, solvate or prodrug thereof.