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