Ethyl 2-amino-5-cyano-3-(difluoromethyl)pyridine-4-carboxylate
Methyl 5-amino-2-cyano-3-(difluoromethyl)pyridine-4-carboxylate
Methyl 4-amino-5-cyano-3-(difluoromethyl)pyridine-2-carboxylate
Methyl 2-amino-3-cyano-5-(difluoromethyl)pyridine-6-acetate