Ethyl 2-amino-4-(bromomethyl)-5-(difluoromethyl)pyridine-3-carboxylate
Ethyl 3-amino-2-(chloromethyl)-4-(difluoromethyl)pyridine-6-carboxylate
Ethyl 2-amino-3-(bromomethyl)-6-(difluoromethyl)pyridine-5-carboxylate
Ethyl 2-amino-6-(chloromethyl)-3-(difluoromethyl)pyridine-5-carboxylate