Patent ID: RE39384

Claim:
A compound of formula (I): or a tautomeric form thereof, wherein: R 1 represents a hydrogen atom, C 1-12 alkyl, C 1-12 alkoxy, C 1-12 alkylcarbonyl or arylC 1-12 alkyl; A 1 represents hydrogen or 1 to 4 optional substituents selected from the group consisting of: C 1-12 alkyl, C 1-12 alkoxy, aryl and halogen; aryl represents phenyl or naphthyl optionally substituted with up to five groups selected from halogen, C 1-12 alkyl, phenyl, C 1-12 alkoxy, haloC 1-12 alkyl, hydroxy, nitro, C 1-12 alkoxycarbonyl, C 1-12 alkoxycarbonyl, C 1-12 alkoxycarbonyloxy, or C 1-12 alkylcarbonyl; A 2 represents a benzene ring having 1 to 3 optional substituents selected from hydrogen, halogen, C 1-12 alkyl, C 1-12 alkoxy; and M − represents a counter-ion other than the maleate ion which is 5 - [ 4 - [ 2 -( N - methyl - N -( 2 - pyridyl ) amino ) ethoxy]benzyl]thiazolidine - 2 , 4 - dione tartaric acid salt or a tautomer of 5 -[ 4 - [ 2 -( N - methyl - N -( 2 - pyridyl ) amino ) ethoxy]benzyl]thiazolidine - 2 , 4 - dione tartaric acid salt.