3-Amino-4-(bromomethyl)-5-(difluoromethyl)pyridine-2-carboxylic acid
3-Amino-5-(chloromethyl)-2-(difluoromethyl)pyridine-6-carboxylic acid
3-Amino-2-(bromomethyl)-5-(difluoromethyl)pyridine-4-carboxylic acid
6-Amino-3-(chloromethyl)-2-(difluoromethyl)pyridine-4-carboxylic acid