• Bulletin of the Korean Chemical Society
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• v.23 no.11
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• pp.1677-1679
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• 2002

• Bulletin of the Korean Chemical Society
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• v.20 no.11
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• pp.1309-1312
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• 1999

Two chiral stationary phases (CSPs) derived from two diastereomers consisting of (R)- or(S)-α-naphthylethylamine and (S)-naproxen were found to show different chromatographic behaviors in resolving N-(3,5-dinitrobenzoyl)-α-arylalkylamines and N-(3,5-dinitrobenzoyl)-α- or β-amino amides and esters. From the different chromatographic resolution behaviors on the two CSPs, the chiral recognition is proposed to be controlled mainly by the (R)- or (S)-α-naphthylethylamine part of the CSP. In contrast, the (S)-naproxen part of the two CSPs is proposed to exert some subordinate effects on the chiral recognition.

• Bulletin of the Korean Chemical Society
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• v.24 no.7
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• pp.911-915
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• 2003

Two liquid chromatographic chiral stationary phases (CSPs) based on (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid were successfully applied in the resolution of racemic tocainide and its analogues. In the resolution of tocainide, especially, the CSP containing N-CH₃ amide tethering groups was quite effective, showing clear baseline resolution (RS: 2.66) with reasonable enantioselectivity ( a: 1.25). Consequently, the CSP containing N-CH₃ amide tethering groups is expected to be useful to monitor the enantiomeric composition of tocainide in clinical samples. In addition, the chromatographic behaviors for the resolution of tocainide and its analogues on the two CSPs were found controllable by varying the content and the type of organic and acidic modifiers in aqueous mobile phase.

• Journal of Integrative Natural Science
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• v.8 no.2
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• pp.111-116
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• 2015

Liquid chromatographic enantiomer separation of ${\alpha}$-amino acid esters as nitrobenzoxadiazole (NBD) derivatives was performed using several chiral stationary phases (CSPs) based on polysaccharide derivatives under fluorescence detection. For enantiomer separation by normal HPLC, the non-aqueous derivatization method of ${\alpha}$-amino acid esters for NBD analytes was introduced. Among the six CSPs used in this study, the performance of Chiralpak IA was superior for enantiomer resolution of NBD derivatives of several ${\alpha}$-amino acid methyl esters. Also the convenient analytical method using polysaccharide-derived CSPs developed in this study was applied to determine the optical purity of ${\alpha}$-amino acids esters. It was investigated that the enantiomeric impurity levels of 0.02-1.73% were found after determination of enantiomeric purities of several commercially available L-amino acid methyl esters. It is expected to be quite useful for enantiomer separation of other ${\alpha}$-amino acid esters as NBD derivatives by normal HPLC.

• Bulletin of the Korean Chemical Society
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• v.26 no.5
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• pp.823-825
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• 2005

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2201-2206
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• 2010

To improve the separation property and stability of metal chelate Cu(II) column, three new kinds of multidentate aminocarboxy silica columns with cation-exchange properties were synthesized using glutamic acid (Glu), glutamic acidbromoacetic acid (Glu-BAA), glutamic acid-bromosuccinic acid (Glu-BSUA) as ligands and silica gel as matrix. The standard proteins were separated with prepared chromatographic columns. The stationary phases exhibited the metal chelate property after fixing copper ion (II) on the synthesized multidentate ligand silica columns. The binding capacity of immobilized metal ion was related with the dentate number of multidentate ligands. Chromatographic behavior of proteins and the leakage of immobilized metal ion on multidentate chelate Cu(II) columns were affected by the dentate number of multidentate ligands and competitive elution system directly. The results showed that quinquedentate Glu-BSUA-Cu(II) column exhibited better chromatographic property and stability as compared with tridentate Glu-Cu(II) column, tetradentate Glu-BAA-Cu(II) column and commonly used IDA-Cu(II) column.

• Bulletin of the Korean Chemical Society
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• v.26 no.7
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• pp.1132-1134
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• 2005

• Bulletin of the Korean Chemical Society
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• v.8 no.1
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• pp.45-47
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• 1987

After conversion to their 3,5-dinitrobenzoyl or 3,5-dinitroanilide derivatives, the enantiomers of a number of drugs may be chromatographically separated on various ${\alpha}$-arylalkylamine-derived chiral stationary phases (CSPs). While each CSP used in this study is useful, CSP 1 is best able to resolve the 3,5-dinitroanilide derivative of Ibuprofen while CSP 9 generally gives rather large ${\alpha}$ values for the resolution of 3,5-dinitrobenzoyl derivatives of the enantiomers of ${\beta}$-adrenergic blocking drugs.

• Bulletin of the Korean Chemical Society
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• v.10 no.6
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• pp.578-581
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• 1989

Two enantiomers of various 2-hydroxy acid esters have been resolved as the 3,5-dinitrophenyl carbamates on chiral stationary phases (CSPs) derived from ${\alpha}-arylalkylamines.$ Two CSPs, each of which contains the same type of chiral moiety, but shows different mode of connection to a silica support, have been found to show the contrasting resolution behaviors. From the contrasting resolution behaviours of two CSPs used in this study, two competing chiral recognition mechanisms are proposed.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.285.1-285.1
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• 2003

ChiroSil RCA(+) and SCA(-) HPLC chiral stationary phases (CSPs) developed by covalently bonding (+)- and (-)-(18-crown-6)-2,3,11,12-tetracarboxylic acid (18-C-6-T A) to silica gel were employed for enantioresolution of racemic amino compounds, respectively. Also, these 18-C-6-TA covalently bonded CSPs were compared to a commercially available Crownpak CR CSP prepared by coating chiral crown ether as a chiral selector on ODS column. (omitted)