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