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