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