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