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