Ethyl 5-bromo-2-(difluoromethyl)-3-nitropyridine-6-carboxylate
Ethyl 4-bromo-5-(difluoromethyl)-2-nitropyridine-3-carboxylate
Ethyl 4-bromo-5-(difluoromethyl)-3-nitropyridine-2-carboxylate
Ethyl 4-bromo-3-(difluoromethyl)-2-nitropyridine-6-carboxylate