Comparison of several polysaccharide-derived chiral stationary phases for the enantiomer separation of N-fluorenylmethoxycarbonyl alpha-amino acids by HPLC.

The liquid chromatographic enantiomer separation of N-fluorenylmethoxycarbonyl (FMOC) protected alpha-amino acids was performed on nine polysaccharide-derived chiral stationary phases (CSPs). The cellulose derived coated CSPs, Chiralcel OD-H (separation factor = 1.09-2.

Chiral discrimination studies of (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid by high-performance liquid chromatography and NMR spectroscopy.

Chiral discrimination studies using (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid (18-C-6-TA) as a chiral selector were performed by high-performance liquid chromatography (HPLC) and NMR spectroscopy. The enantiomers of alanine (Ala) or alanine methyl ester (Ala-ME) were well separated on the chiral stationary phases (CSPs) derived from (+)-18-C-6-TA by HPLC. The chiral selector, (+)-18-C-6-TA, used in the CSP was also applied for the chiral discrimination of the Ala and Ala-ME enantiomers, and it discriminated these enantiomers successfully by NMR spectroscopy.

Lipase mediated chiral resolution of 4-arylthio-2-butanol as an intermediate for beta-lactam antibiotics.

This paper deals with chiral enzymatic resolution of 4-arylthio-2-butanols by lipase to prepare potential intermediates of beta-lactam antibiotics. Among several lipases employed, lipase P type enzyme gave the highest ee value to prepare (R)-4-arylthio-2-butyl acetate. The enzymatic resolution of phenyl substituted alcohol (6a) using lipase P showed the highest ee value (99.