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