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