| abstract |
The invention relates to a method for producing 2 - [(3,5-difluoro-3'-methoxy-1,1'-biphenyl-4-yl) amino] nicotinic acid, which includes the following steps: a) using 3,5-difluoro- 3'-methoxybiphenyl-4-amine; b) preparation and isolation of the 3,5-difluoro-3'-methoxybiphenyl-4-amine aminium salt; and c) additional reaction of the 3,5-difluoro-3'-methoxybiphenyl-4-amine aminium salt obtained in step b) with obtaining 2 - [(3,5-difluoro-3'-methoxy-1,1'-biphenyl-4-yl) amino] nicotinic acid. |