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C14H12O6S 308.31
Benzenesulfonic acid, 5-benzoyl-4-hydroxy-2-methoxy-.
5-Benzoyl-4-hydroxy-2-methoxybenzenesulfonic acid [4065-45-6].
» Sulisobenzone contains not less than 95.0 percent and not more than 105.0 percent of C14H12O6S, calculated on the as-is basis.
Packaging and storage— Preserve in tight, light-resistant containers.
Identification, Ultraviolet Absorption 197U
Solution: 10 µg per mL.
Medium: water.
Absorptivities do not differ by more than 3.0%.
Residual solvents 467: meets the requirements.
(Official January 1, 2007)
Assay— Accurately weigh about 1 g of Sulisobenzone, and dissolve in 20 mL of water in a conical flask. Add 200 mL of dehydrated isopropyl alcohol, titrate a portion with 0.1 N tetrabutylammonium hydroxide VS, and determine the two endpoints potentiometrically. Calculate the amount, in mg, of C14H12O6S in the portion of Sulisobenzone taken by the formula:
308.31C(2V1 V2),
in which 308.31 is the empirical weight of sulisobenzone; C is the concentration, in moles per liter, of the 0.1 N tetrabutylammonium hydroxide VS; and V1 and V2 are the volumes, in mL, of titrant needed to reach the first and second endpoints, respectively.
Auxiliary Information— Staff Liaison : Feiwen Mao, M.S., Senior Scientific Associate
Expert Committee : (MDOOD05) Monograph Development-Ophthalmics Oncologics and Dermatologicals
USP29–NF24 Page 2046
Pharmacopeial Forum : Volume No. 28(4) Page 1193
Phone Number : 1-301-816-8320