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