title: Preparation and evaluation of novel chiral stationary phases based on quinine derivatives comprising crown ether moieties.
abstract: The C9-position of quinine was modified by meta- or para-substituted benzo-18-crown-6, and immobilized on 3-mercaptopropyl-modified silica gel through the radical thiol-ene addition reaction. These two chiral stationary phases were evaluated by chiral acids, amino acids, and chiral primary amines. The crown ether moiety on the quinine anion exchanger provided a ligand-exchange site for primary amino groups, which played an important role in the retention and enantioselectivity for chiral compounds containing primary amine groups. These two stationary phases showed good selectivity for some amino acids. The complex interaction between crown ether and protonated primary amino group was investigated by the addition of inorganic salts such as LiCl, NH4Cl, NaCl, and KCl to the mobile phase. The resolution results showed that the simultaneous interactions between two function moieties (quinine and crown ether) and amino acids were important for the chiral separation.
authors.affiliation: Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, Shanghai, China.
authors.forename: Dongqiang
authors.initials: D
authors.lastname: Wang
authors.forename: Jianchao
authors.initials: J
authors.lastname: Zhao
authors.forename: Haixia
authors.initials: H
authors.lastname: Wu
authors.forename: Haibo
authors.initials: H
authors.lastname: Wu
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Cai
authors.forename: Yanxiong
authors.initials: Y
authors.lastname: Ke
authors.forename: Xinmiao
authors.initials: X
authors.lastname: Liang
mesh_terms: D002851:Chromatography, High Pressure Liquid; D043844:Crown Ethers / Q000737:chemistry*; D011803:Quinine / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism
chemical_list: D043844:Crown Ethers; D011803:Quinine
keywords: Amino acids; Chiral stationary phases; Crown ethers; Enantiomer separation; Quinine