4-Fluoro-3-hydroxy-2-nitro-6-(trifluoromethoxy)pyridine
3-Fluoro-4-hydroxy-6-nitro-2-(trifluoromethoxy)pyridine
4-(Difluoromethyl)-6-fluoro-3-(trifluoromethoxy)pyridine-2-carboxylic acid
3-(Difluoromethyl)-2-fluoro-4-(trifluoromethoxy)pyridine-5-carboxylic acid