Synonyms: 1(3h)-isobenzofuranone, 3-[4-hydroxy-2-methyl-5-(1-methylethyl)phenyl]-3-[2-methyl-5-(1-methylethyl)-4-(phosphonooxy)phenyl]-;1(3H)-Isobenzofuranone, 3-(4-hydroxy-2-methyl-5-(1-methylethyl)phenyl)-3-(2-methyl-5-(1-methylethyl)-4-(phosphonooxy)phenyl)-;17016-43-2;EINECS 241-090-3;AC1L3BOB;AC1Q6RWM;10496-54-5;Thymolphthalein monophosphate;KST-1B7928;AR-1B1484;10496-54-5 (mono-magnesium salt);62796-27-4 (di-hydrochloride salt);68991-94-6 (unspecified magnesium salt);28749-63-5 (unspecified hydrochloride salt);67953-09-7 (magnesium-hydrochloride[2:1:4] salt);Phenolphthalein, 5',5''-diisopropyl-2',2''-dimethyl-, mono(dihydrogen phosphate);[4-[1-(4-hydroxy-2-methyl-5-propan-2-ylphenyl)-3-oxo-2-benzofuran-1-yl]-5-methyl-2-propan-2-ylphenyl] dihydrogen phosphate;4-(3-(4-Hydroxy-5-isopropyl-o-tolyl)-1-oxo-3H-isobenzofuran-3-yl)-6-isopropyl-m-tolyl dihydrogen phosphate;4-{1-[4-hydroxy-2-methyl-5-(propan-2-yl)phenyl]-3-oxo-1,3-dihydro-2-benzofuran-1-yl}-5-methyl-2-(propan-2-yl)phenyl dihydrogen phosphate