Title: 4¢,5¢-Dibromofluorescein
CAS Registry Number: 596-03-2
CAS Name: 4¢,5¢-Dibromo-3¢,6¢-dihydroxyspiro[isobenzofuran-1(3H),9¢-[9H]xanthen]-3-one
Additional Names: 4,5-dibromo-3,6-fluorandiol; D & C Orange No. 5; C.I. Solvent Red 72; C.I. 45370:1
Molecular Formula: C20H10Br2O5
Molecular Weight: 490.10
Percent Composition: C 49.01%, H 2.06%, Br 32.61%, O 16.32%
Literature References: Prepn from fluorescein, q.v.: A. Baeyer, Ann. 183, 1 (1876); M. A. Phillips, J. Chem. Soc. 1932, 724. Metabolism: J. M. Webb et al., J. Pharmacol. Exp. Ther. 137, 141 (1962). See also: Colour Index vol. 4 (3rd ed., 1971) p 4425.
Properties: Red plates, mp 285°. Slightly sol in water (orange with faint yellow fluorescence); sol in ethanol (orange with greenish-yellow fluorescence) and in acetone (pink with yellow fluorescence). Red-yellow soln in conc H2SO4, turning yellow-brown with orange ppt on dilution. Absorption spectra: R. C. Gibbs, C. V. Shapiro, J. Am. Chem. Soc. 51, 1769 (1929).
Melting point: mp 285°
Derivative Type: Disodium salt
Additional Names: C.I. Acid Orange 11
Molecular Formula: C20H8Br2Na2O5
Molecular Weight: 534.06
Percent Composition: C 44.98%, H 1.51%, Br 29.92%, Na 8.61%, O 14.98%
Use: D & C Orange No. 5 permitted for use in lipsticks, mouthwashes and dentifrices: Fed. Regist. 47, 49632 (1982). |