phthaleins

3,3-Bis(hydroxyaryl)-2-benzofuran-1(3H)-ones generally derived from the condensation of phthalic anhydride with phenols. E.g. phenolphthalein.
P04662
See: xanthenes
Source:
PAC, 1995, 67, 1307 (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1359