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