Term: sulfonphthaleins
https://doi.org/10.1351/goldbook.S06122

Definition:
3,3-Bis(hydroxyaryl)-3H-2,1-benzoxathiole S,S-dioxides, formed by condensation of o-sulfobenzoic acid with phenols or related compounds, e.g. S06122.png 

Related Terms:
1) phenols (http://doi.org/10.1351/goldbook.P04539).
2) phthaleins (http://doi.org/10.1351/goldbook.P04662).

Image: Not defined (https://goldbook.iupac.org/img/inline/S06122.png) 

Source: PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1370 (https://doi.org/10.1351/pac199567081307)

Citation: 'sulfonphthaleins' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.S06122

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