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