Chiral counter-current chromatography of gemifloxacin guided by capillary electrophoresis using (+)-(18-crown-6)-tetracarboxylic acid as a chiral selector

摘要

(+)-(18-crown-6)-tetracarboxylic acid (18C6H(4)) has been known as a highly efficient chiral selector for resolving primary amine enantiomers in capillary electrophoresis (CE). We investigated the chiral separation of gemifloxacin using 18C6H(4) in analytical counter-current chromatography (CCC). The separation conditions for CE, including the binding constant, pH, and run buffer constituents, provided a helpful guideline for chiral CCC. A successful separation of gemifloxacin enantiomers could be achieved using a two-phase solvent system composed of 1-butanol-ethyl-acetate-bis(2-hydroxyethyl)aminotris(hydroxymethyl)methane acetate buffer with a small amount of 18C6H(4). The hydrophobicity of the solvent system and the 18C6H(4) concentration were varied to optimize the chiral separation. (C) 2004 Elsevier B.V. All rights reserved.