1(3H)-Isobenzofuranone, 3,3-bis(3,5-dibromo-4-hydroxyphenyl)- 3',3'',5',5''-Tetrabromophenolphthalein 76-62-0 NSC21261 Phenolphthalein, 3',3'',5',5''-tetrabromo- Tetrabromophenolphthalein