Ethyl 3-amino-5-(difluoromethyl)-4-methoxypyridine-2-carboxylate
Ethyl 3-amino-6-(difluoromethyl)-2-methoxypyridine-5-carboxylate
Ethyl 5-amino-4-(difluoromethyl)-2-methoxypyridine-3-carboxylate
Ethyl 5-amino-2-(difluoromethyl)-3-methoxypyridine-6-carboxylate