CAS No 143-74-8 , 4-[3-(4-hydroxyphenyl)-1,1-dioxo-2,1λ

Title: Phenolsulfonphthalein
CAS Registry Number: 143-74-8
CAS Name: 4,4￠-(3H-2,1-Benzoxathiol-3-ylidene)bisphenol S,S-dioxide
Synonyms: a-hydroxy-a,a-bis(p-hydroxyphenyl)-o-toluenesulfonic acid g-sultone; 3,3-bis(p-hydroxyphenyl)-3H-2,1-benzoxathiole 1,1-dioxide; phenol red; P.S.P.
Trademarks: Sulfonphthal
Molecular Formula: C19H14O5S
Molecular Weight: 354.38
Percent Composition: C 64.40%, H 3.98%, O 22.57%, S 9.05%
Literature References: Prepd by the action of o-sulfobenzoic anhydride or of o-sulfobenzoyl chloride on phenol: Kekulé, Barbaglia, Ber. 5, 876 (1872); Kekulé, Ber. 6, 943 (1873); Heumann, Kochlin, Ber. 15, 1118 (1882); DE 142116; Chem. Zentralbl. II, 79 (1903); Orndorff, Sherwood, J. Am. Chem. Soc. 45, 486 (1923). Diagnostic use: G. Dunea, P. Freedman, J. Am. Med. Assoc. 204, 159 (1968); R. D. Wilkes et al., Vet. Med. Small Anim. Clin. 76, 289 (1981). Molecular structure: K. Yamaguchi et al., Anal. Sci. 13, 521 (1997).
Properties: Bright red to dark red crystals. Stable in air. pK = 7.9. d 1.445 Mg m-3. One gram dissolves in ~1300 ml water, in ~350 ml alc, in 500 ml acetone. Almost insol in chloroform, ether. Readily sol in aq alkali hydroxides or carbonates with red color, which is discharged by boiling with zinc dust.
pKa: pK = 7.9
Density: d 1.445 Mg m-3
Use: As indicator in 0.02-0.05% alcohol soln. pH 6.8 yellow, 8.4 red.
Therap-Cat: Diagnostic aid (renal function).
Therap-Cat-Vet: Diagnostic aid (renal function).
Keywords: Diagnostic Aid.