3-Cyano-2-nitro-4-(trifluoromethoxy)pyridine-6-carboxylic acid
2-Chloro-6-nitro-3-(trifluoromethoxy)pyridine-5-carboxylic acid
2-Cyano-3-(trifluoromethoxy)-4-(trifluoromethyl)pyridine-6-carboxylic acid
2-Cyano-6-nitro-3-(trifluoromethoxy)pyridine-5-carboxylic acid