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