• Title/Summary/Keyword: 키랄

Search Result 82, Processing Time 0.023 seconds

Effect of acid or base additive in the mobile phase on enantiomer separation of amino alcohols using polysaccharide derived chiral columns (다당유도체를 기초로 한 키랄 컬럼에서 이동상에서의 산 또는 염기 첨가제가 아미노 알코올의 광학분리에 미치는 영향)

  • Huang, Hu;Jin, Jing Yu;Lee, Wonjae
    • Analytical Science and Technology
    • /
    • v.22 no.4
    • /
    • pp.313-318
    • /
    • 2009
  • Liquid chromatographic enantiomer separation of amino alcohols was performed on several chiral columns based on polysaccharide derivatives under the mobile phase conditions containing acid or base additive. The chromatographic parameters were greatly influenced by the nature of the mobile phase containing acid or base additive as well as the used chiral columns. Compared to chromatographic results obtained in the mobile phase containing base additive (0.1% triethylamine), especially, Chiralcel OD showed dramatically enhanced separation factors and resolution factors with reduced capacity factors under the mobile phase condition containing acidic additive (0.1% trifluoroacetic acid). When the mobile phase containing 0.05% trifluoroacetic acid and 0.05% triethylamine was used on Chiralcel OD, the greatest separation factors and resolution factors among all other mobile phase conditions in this study were observed.

Enantiomer Separation of Chiral Amino Alcohols as 9-anthraldimine Derivatives on Coated and Covalently Bonded Chiral Stationary Phases Based on Polysaccharide Derivatives by High Performance Liquid Chromatography (고성능 액체 크로마토그래피에 의한 다당 유도체를 기초로 한 흡착되거나 공유결합된 키랄 고정상에서 키랄 아미노 알코올의 안트르알디민 유도체의 광학분리)

  • Xu, Wen Jun;Jin, Jing Yu;Lee, Won-Jae
    • KSBB Journal
    • /
    • v.26 no.4
    • /
    • pp.323-327
    • /
    • 2011
  • The convenient derivatization method of chiral amino alcohols as 9-anthraldimine Schiff base derivatives for chiral resolution was developed and the liquid chromatographic enantiomer separation of chiral amino alcohols as 9-anthraldimine derivatives was investigated on several coated and covalently bonded polysaccharide-derived chiral stationary phases (CSPs). In general, the performance of Chiralcel OD-H (or Chiralcel OD) (${\alpha}$ = 1.24-2.89), the coated CSP derived from cellulose derivative was superior to the other CSPs for resolution of 9-anthraldimine derivatives of several amino alcohols. The results of enantioseparation depending on the structure of 9-anthraldimine analytes like the steric bulky group and the polar moiety etc were discussed. The analytical method was applied to measure the enantiomeric purity of commercially available chiral amino alcohols. It is expected that the convenient analytical method will be very efficient for determination of enantiomeric purity of amino alcohols as 9-anthraldimine Schiff base derivatives with strong UV absorption.

The Development and Application of Chirotechnology Using Chiral Crown Ethers for Enantiomer Separation (광학분리를 위한 키랄 크라운 에테르를 이용한 키랄공학의 개발과 응용)

  • Paik, Man-Jeong;Yun, Won-Nam;Lee, Won-Jae
    • KSBB Journal
    • /
    • v.27 no.4
    • /
    • pp.199-206
    • /
    • 2012
  • Chiral crown ethers are synthetic macrocyclic polyethers that bind protonated chiral primary amines with high selectivity and affinity. They have been widely used to separate or distinguish the enantiomers of chiral compounds containing a primary amino moiety by high-performance liquid chromatography, capillary electrophoresis, and NMR spectroscopy. In this paper, two important chiral crown ethers including chiral binaphthyl unit and (18-crown-6)-2,3,11,12-tetracarboxylic acid as chiral selectors are focused. And several chiral resolution techniques and their applications in chirotechnology using these chiral crown ethers with related chiral recognition mechanism studies are reviewed. Especially, it was shown that the commercially available HPLC columns based on (18-crown-6)-2,3,11,12-tetracarboxylic acid have been developed and successfully applied for the resolution of various primary amino compounds including amino acids.

Comparative Enantiomer Separation on Chiral Stationary Phases Derived from Chiral Crown Ether by HPLC (고성능 액체 크로마토그래피에서 키랄 크라운 에테르로부터 유도된 키랄 고정상을 이용한 광학분리의 비교)

  • Huang, Hu;Jeon, So-Hee;Kim, Ji-Yeon;Lee, Won-Jae
    • KSBB Journal
    • /
    • v.27 no.4
    • /
    • pp.232-236
    • /
    • 2012
  • Comparative liquid chromatographic enantiomer separation of ${\alpha}$-amino acids, their esters and primary amino compounds was performed using two chiral stationary phases (CSPs) prepared by covalently bonding (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid (18-C-6-TA) of the same chiral selector. In general, the separation factors and resolution factors for these analytes on CSP 1 were greater than on CSP 2, while these capacity factors on CSP 2 were quite greater than on CSP 1. Except for leucine methyl ester and phenylalanine methyl ester, the elution orders of all analytes including ${\alpha}$-amino ${\alpha}$-alkyl acids and phenylglycine alkyl esters on CSP 1 are identical to those on CSP 2. This study showed that different connecting structures for these two CSPs might influence their ability to resolve the analytes depending on their structures related to the chiral recognition mechanism.

Effect of Mobile Phase Additive on Enantiomer Resolution for Chiral Amines on Polysaccharide-derived Chiral Stationary Phases by High Performance Liquid Chromatography (고성능 액체크로마토그래피의 다당유도체를 기초로 한 키랄 고정상에서 이동상 첨가제가 키랄 아민의 광학분리에 미치는 영향)

  • Paik, Man-Jeong;Yoon, Hye-Ran;Lee, Wonjae
    • KSBB Journal
    • /
    • v.29 no.3
    • /
    • pp.205-209
    • /
    • 2014
  • Chromatographic enantiomer resolution of chiral amines was performed on several covalently immobilized and coated chiral stationary phases (CSPs) based on polysaccharide derivatives under the mobile phase conditions containing base or acid or acid/base additive. The chromatographic parameters including separation factors and capacity factors were greatly influenced by the nature of the mobile phase containing base or acid or salt additive as well as the used CSPs. When 0.05% triethylamine/0.05% trifluoroacetic acid as an additive in the mobile phase was used on all CSPs in this study, the greatest enantiomer resolution was observed except for Chiralpak AD. Also, it was shown that the change of base additive into acid or salt in the mobile phase may directly affect chiral recognition mechanisms between the chiral selectors and analytes occurring during enantiomer separation, resulting in the change of elution orders.

New Liquid Crystalline Methacrylate Polymers Containing 4-Methacryloyloxyphenoxy Group and 4'-((S)-(+)-2-Methylbutoxy)biphenyl-4-carboxyl Mesogenic Group: 1. Synthesis and Characterization of the Monomers (4-Methacryloyloxyphenoxy기와 4'-((S)-(+)-2-methylbutoxy)biphenyl-4-carboxyl 메소겐기를 갖는 새로운 메타크릴레이트 액정화합물: 1. 단량체의 합성 및 특성)

  • So, Bong-Keun;Lee, Sang-Ho;Lee, Soo-Min
    • Journal of the Korean Chemical Society
    • /
    • v.48 no.6
    • /
    • pp.599-608
    • /
    • 2004
  • New two kinds of methacrylate monomers having a benzene ring inserted between spacer and methacryloyl group and the chiral center connected to the terminal of the mesogenic structures were synthesized. In these two series the effects for the formation of the liquid crystals in regard to the length changes of the spacers and mesogenic groups were investigated. The first series did not show any liquid crystalline phases in the intermediate compounds nor in the end products. However, the methacrylates of second series showed the liquid crystalline phases in the intermediate compounds as well as in the final products regardless of the length of the spacers.