Chiral separation and determination of the optical purity of thiamphenicol-related chiral compound by capillary zone electrophoresis with cyclodextrins as chiral selectors

Capillary zone electrophoresis has been used for the chiral separation of two thiamphenicol-related compounds, D-threo-3-(4-methylsufonylphenyl)serinate (MSS) and D-threo-2-amino-1-(4-methylthiophenyl) 1,3-propanediol (AMP), with cyclodextrins (CD) as chiral additives. Of the six CD tested, α-CD, β-CD, γ-CD, hepatakis-2,6-di-O-methyl-β-CD (DM-β-CD), heptakis-2,3,6-tri-O-methyl-β-CD (TM-β-CD) and 2-hydroxypropyl-β-CD (HP-β-CD), use of HP-β-CD alone resulted in chiral recognition of the enantiomers of MSS and AMP. The effects of HP-β-CD concentration, buffer concentration, and applied voltage on chiral resolution were investigated. Under optimum conditions the enantiomers of both MSS (2S,3R and 2R,3S) and AMP (2R,3R and 2S,3S) could be separated to baseline simultaneously. This method was used successfully for determination of 0.88% 2S,3S-AMP present as an optical impurity in a sample of 2R,3R-AMP.