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