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