7247. Phenolsulfonphthalein

Nomenclature

CAS number: 143-74-8
4,4′-(1,1-Dioxido-3H-2,1-benzoxathiol-3-ylidene)bisphenol; 4,4′-(3H-2,1-benzoxathiol-3-ylidene)bisphenol S,S-dioxide; α-hydroxy-α,α-bis(p-hydroxyphenyl)-o-toluenesulfonic acid γ-sultone; 3,3-bis(p-hydroxyphenyl)-3H-2,1-benzoxathiole 1,1-dioxide; phenol red; P.S.P.; Sulfonphthal.
C19H14O5S; mol wt 354.38.
C 64.40%, H 3.98%, O 22.57%, S 9.05%.

Description and 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).

Chemical structure

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.

Derivative

Sodium salt.

Nomenclature

CAS number: 34487-61-1
C19H13NaO5S; mol wt 376.36.
C 60.63%, H 3.48%, Na 6.11%, O 21.26%, S 8.52%.

Use

As indicator in 0.02-0.05% alcohol soln. pH 6.8 yellow, 8.4 red.

Therapeutic Category

Diagnostic aid (renal function).

Therapeutic Category (Veterinary)

Diagnostic aid (renal function).

Keywords

Diagnostic Aid