4-(Difluoromethyl)-3-hydroxy-2-nitropyridine-5-carboxylic acid
2-(Difluoromethyl)-5-hydroxy-6-methoxy-3-(trifluoromethyl)pyridine
3-(Difluoromethyl)-5-hydroxy-2-nitropyridine-4-carboxylic acid
5-(Difluoromethyl)-3-hydroxy-4-methylpyridine-2-carboxylic acid