4-Cyano-3-fluoro-6-(trifluoromethoxy)pyridine-2-carboxylic acid
4-Cyano-3-fluoro-2-(trifluoromethoxy)pyridine-6-carboxylic acid
4-Cyano-2-fluoro-3-(trifluoromethoxy)pyridine-6-carboxylic acid
3-Cyano-5-fluoro-6-(trifluoromethoxy)pyridine-2-carboxylic acid