6-Cyano-3-hydroxy-2-(trifluoromethoxy)pyridine-4-sulfonyl chloride
2-Cyano-4-hydroxy-3-(trifluoromethoxy)pyridine-6-sulfonyl chloride
3-Chloro-2-hydroxy-4-(trifluoromethoxy)pyridine-6-sulfonyl chloride
2-Chloro-6-hydroxy-3-(trifluoromethoxy)pyridine-5-sulfonyl chloride