2-(4,5-Dibromo-6-hydroxy-3-oxo-3H-xanthen-9-yl)benzoic acid 5350-25-4 Benzoic acid, 2-(4,5-dibromo-6-hydroxy-3-oxo-3H-xanthen-9-yl)- Fluorescein, 4',5'-dibromo- NSC 6