4-Chloro-5-(difluoromethyl)-2-fluoropyridine-3-carboxylic acid
4-Chloro-5-(difluoromethyl)-3-fluoropyridine-2-carboxylic acid
4-Chloro-3-(difluoromethyl)-2-fluoropyridine-6-carboxylic acid
4-Chloro-6-(difluoromethyl)-2-fluoropyridine-3-carboxylic acid