4-Bromo-3-(difluoromethyl)-5-hydroxypyridine-2-carboxylic acid
4-Bromo-3-(difluoromethyl)-2-hydroxypyridine-5-carboxylic acid
4-Bromo-5-(difluoromethyl)-2-hydroxypyridine-3-carboxylic acid
4-Bromo-5-(difluoromethyl)-3-hydroxypyridine-2-carboxylic acid