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