Complementary use of counter-current chromatography and preparative reversed-phase high-performance liquid chromatography in the separation of a synthetic mixture of brominated tetrachlorofluoresceins.
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.
Weisz
A
A
Division of Colors and Cosmetics, US Food and Drug Administration, Washington, DC 20204.
Scher
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AL
Andrzejewski
D
D
Shibusawa
Y
Y
Ito
Y
Y
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
D005452:Fluoresceins; D010697:Eosine I Bluish