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