Synonyms: Chlorsulphalein;Chlorsulphthalein;Phenolphthalein, 4,5,6,7-tetrachloro-3',3''-disulfo-, disodium salt (7CI,8CI);Benzenesulfonic acid, 3,3'-(4,5,6,7-tetrachloro-3-oxo-1(3H)-isobenzofuranylidene)bis(6-hydroxy-, disodium salt;AC1L5895;LS-32062;5182-09-2;disodium 2-hydroxy-5-[4,5,6,7-tetrachloro-1-(4-hydroxy-3-sulfonatophenyl)-3-oxo-2-benzofuran-1-yl]benzenesulfonate