title: Complementary use of counter-current chromatography and preparative reversed-phase high-performance liquid chromatography in the separation of a synthetic mixture of brominated tetrachlorofluoresceins.
abstract: A synthetically prepared mixture of brominated 4,5,6,7-tetrachlorofloresceins was separated by a combination of preparative reversed-phase high-performance liquid chromatography and high-speed counter-current chromatography. Two new lower-brominated subsidiary colors of D&C Red Nos. 27 and 28 (phloxine B), 4',5'-dibromo-4, 5,6,7-tetrachlorofluorescein and 2',4',5'-tribromo-4,5,6, 7-tetrachlorofluorescein, were isolated and characterized by 1H NMR and chemical ionization mass spectrometry.
authors.affiliation: Division of Colors and Cosmetics, US Food and Drug Administration, Washington, DC 20204.
authors.forename: A
authors.initials: A
authors.lastname: Weisz
authors.forename: A L
authors.initials: AL
authors.lastname: Scher
authors.forename: D
authors.initials: D
authors.lastname: Andrzejewski
authors.forename: Y
authors.initials: Y
authors.lastname: Shibusawa
authors.forename: Y
authors.initials: Y
authors.lastname: Ito
mesh_terms: D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D010697:Eosine I Bluish / Q000032:analysis*; D005452:Fluoresceins / Q000032:analysis*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry
chemical_list: D005452:Fluoresceins; D010697:Eosine I Bluish