Ethyl 3-(difluoromethyl)-2-nitro-6-(trifluoromethyl)pyridine-5-carboxylate
Ethyl 3-(difluoromethyl)-2-nitro-5-(trifluoromethyl)pyridine-6-carboxylate
Ethyl 6-(difluoromethyl)-2-nitro-3-(trifluoromethyl)pyridine-4-carboxylate
Ethyl 6-(difluoromethyl)-2-nitro-4-(trifluoromethyl)pyridine-3-carboxylate