Patent ID: 8524951

Claim:
A process for producing a compound represented by the formula (III) comprising separating a compound represented by the formula (III): (wherein R 1 and R 2 are each independently hydrogen, halogen, carboxy, nitro, optionally substituted alkyl, optionally substituted alkoxy, optionally substituted alkylsulfonyl, optionally substituted arylsulfonyl, or optionally substituted sulfamoyl, or R 1 and R 2 , when a binding carbon atom is adjacent, may be taken together with an adjacent carbon atom to form an optionally substituted ring) from a compound represented by the formula (II): (wherein R 1 and R 2 are each independently hydrogen, halogen, carboxy, nitro, optionally substituted alkyl, optionally substituted alkoxy, optionally substituted alkylsulfonyl, optionally substituted arylsulfonyl, or optionally substituted sulfamoyl, or R 1 and R 2 , when a binding carbon atom is adjacent, may be taken together with an adjacent carbon atom to form an optionally substituted ring).