CAS No 27503-81-7 , 2-phenyl-3H-benzimidazole-5-sulfonic acid

Title: Ensulizole
CAS Registry Number: 27503-81-7
CAS Name: 2-Phenyl-1H-benzimidazole-5-sulfonic acid
Synonyms: phenylbenzimidazole sulfonic acid
Trademarks: Eusolex 232 (Merck KGaA); Neo Heliopan Hydro (Symrise); Parsol HS (DSM)
Molecular Formula: C13H10N2O3S
Molecular Weight: 274.30
Percent Composition: C 56.92%, H 3.67%, N 10.21%, O 17.50%, S 11.69%
Literature References: UV-B filter in sunscreens and cosmetics. Synergistic increase in SPF occurs in combination with oil-soluble UV absorbers. Prepn: V. G. Sayapin et al., Khim. Geterotsikl. Soedin. 5, 681 (1970), C.A. 73, 45409p (1970). See also: U. Heywang et al., US 5473079 (1995 to Merck Patent GmbH). DNA photosensitization study: C. Stevenson, R. J. H. Davies, Chem. Res. Toxicol. 12, 38 (1999). Photochemical studies: J. J. Inbaraj et al., Photochem. Photobiol. 75, 107 (2002). Fluorometric determn in urine: M. T. Vidal et al., Talanta 59, 591 (2003). Complexation with cyclodextrins: S. Scalia et al., Eur. J. Pharm. Sci. 22, 241 (2004).
Properties: mp 410° (dec). Absorption max (phosphate buffer, pH 7.4): 300 nm. Soly in water: ~0.03%.
Melting point: mp 410°
Absorption maximum: Absorption max (phosphate buffer, pH 7.4): 300 nm
 
Derivative Type: Sodium salt
CAS Registry Number: 5997-53-5
Molecular Formula: C13H9N2NaO3S
Molecular Weight: 296.28
Percent Composition: C 52.70%, H 3.06%, N 9.46%, Na 7.76%, O 16.20%, S 10.82%
Properties: Soly: water >30%; 1,2-propylene glycol >20%.
 
Therap-Cat: Ultraviolet screen.
Keywords: Ultraviolet Screen.