Ethyl 3-cyano-2-(difluoromethyl)-5-hydroxypyridine-6-carboxylate
Methyl 3-cyano-2-(difluoromethyl)-4-fluoropyridine-6-carboxylate
Ethyl 6-cyano-2-(difluoromethyl)-4-hydroxypyridine-3-carboxylate
3-Cyano-2-(difluoromethyl)-4-fluoropyridine-6-acetic acid