Methyl 3-amino-2-(aminomethyl)-4-(difluoromethyl)pyridine-6-acetate
Methyl 2-amino-6-(aminomethyl)-5-(difluoromethyl)pyridine-3-acetate
Methyl 4-amino-5-(difluoromethyl)-2-methylpyridine-3-acetate
Methyl 2-amino-6-(aminomethyl)-3-(difluoromethyl)pyridine-5-acetate