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