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