Methyl 4-amino-3-(aminomethyl)-6-(difluoromethyl)pyridine-2-carboxylate
Methyl 5-amino-4-(chloromethyl)-3-(difluoromethyl)pyridine-2-carboxylate
Methyl 4-amino-3-(aminomethyl)-2-(difluoromethyl)pyridine-6-carboxylate
Methyl 3-amino-4-(chloromethyl)-2-(difluoromethyl)pyridine-5-carboxylate