Sang Cheol Han

  • Citations Per Year
Learn More
A new ligand exchange chiral stationary phase (CSP) has been developed by covalently bonding (R)-N,N-carboxymethyl undecyl phenylglycinol mono-sodium salt onto silica gel and applied in the resolution of alpha- and beta-amino acids. In the resolution of alpha-amino acids, the new CSP was better insome cases than the old one, which was previously developed(More)
A new racemic fluoroquinolone antibacterial agent, gemifloxacin mesylate, has been successfully resolved on a chiral stationary phase (CSP) derived from (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid. Compared to the Crownpak CR(+) column, the CSP used in this study was more effective for the resolution of racemic gemifloxacin mesylate, especially in terms(More)
A residual silanol group-protecting chiral stationary phase (CSP) based on optically active (3,3'-diphenyl-1,1'-binaphthyl)-20-crown-6 was successfully applied to the resolution of fluoroquinolone compounds including gemifloxacin mesylate. The chiral recognition ability of the residual silanol group-protecting CSP was generally greater than that of the(More)
A new liquid chromatographic ligand exchange CSP has been prepared by covalently bonding (S)-N,N-carboxymethyl undecyl leucinol monosodium salt onto silica gel and employed in resolving various alpha-amino acids. The new CSP was quite good in resolving various a-amino acids and the resolution results were dependent on the type and content of organic(More)
A chiral stationary phase (CSP) recently developed by bonding (diphenyl-substituted 1,1'-binaphthyl) crown ether to silica gel for the liquid chromatographic separation of enantiomers was applied to the resolution of investigational fluoroquinolone antibacterial agents including gemifloxacin (formerly LB20304a). All fluoroquinolone compounds used in this(More)
Two chiral stationary phases (CSPs) based on optically active (3,3'-diphenyl-1,1'-binaphthyl)-20-crown-6 covalently bonded to silica gel were utilized for the first time for the resolution of racemic beta-amino acids using high performance liquid chromatography. All of the 10 beta-amino acids tested were resolved on the CSP containing residual(More)
A liquid chromatographic chiral stationary phase (CSP) based on (3,3'-diphenyl-1,1'-binaphthyl)-20-crown-6, which has been utilized in the resolution of alpha-amino acids, amines and amino alcohols, was treated with excess of n-octyltriethoxysilane to prepare a new improved CSP. The residual silanol groups of the original CSP were protected by n-octyl(More)
A new chiral stationary phase (CSP) for the liquid chromatographic separation of enantiomers was prepared by bonding a novel enantiopure (diphenyl-substituted 1,1'-binaphthyl) crown ether to 5 microm silica gel. The resulting CSP was applied to the separation of the enantiomers of various natural and unnatural alpha-amino acids. All alpha-amino acids tested(More)
The addition of the chelating polymer polyacrylic acid (PAA) to assist in the removal of manganese from groundwater by membranes was investigated using membranes with different pore sizes under various operating conditions. Negligible manganese removal was achieved with the UF and NF membranes at acidic pH values, but removals exceeding 90% could be(More)
A liquid chromatographic ligand exchange chiral stationary phase (CSP) derived from (S)-leucinol was applied in the separation of the enantiomers of 12 beta-amino acids. The resolution was quite successful especially for the enantiomers of beta-amino acids containing aromatic functional group in the side chain. The chromatographic resolution behaviors were(More)