4-Amino-6-(difluoromethyl)-3-hydroxypyridine-2-carboxylic acid
4-Amino-2-(difluoromethyl)-5-hydroxypyridine-3-carboxylic acid
4-Amino-2-(difluoromethyl)-3-hydroxypyridine-6-carboxylic acid
4-Amino-2-(difluoromethyl)-3-hydroxypyridine-5-carboxylic acid