4-Cyano-2-(difluoromethyl)-3-hydroxypyridine-5-sulfonyl chloride
3-Cyano-5-(difluoromethyl)-2-hydroxypyridine-4-sulfonyl chloride
Methyl 6-cyano-2-(difluoromethyl)-3-hydroxypyridine-4-carboxylate
6-Chloro-4-(chloromethyl)-2-(difluoromethyl)pyridine-3-methanol