116239-00-0 3172-49-4 32638-88-3 AI3-63037 Benzenesulfonic acid, 2-(4,5,6-trihydroxy-3-oxo-3H-xanthen-9-yl)- EINECS 251-134-3 Pyrogallol sulfonphthalein Spiro(3H-2,1-benzoxathiole-3,9'-(9H)xanthene)-3',4',5',6'-tetrol, 1,1-dioxide