Three stereoselective HPLC methods have been developed for the chiral separation of the enantiomers of three intermediates in the preparation of (+)-tanikolide. The enantiomers were separated on Chiralpak IC (250 × 4.6 mm, 5 μm) in normal phase HPLC. Three intermediates were all baseline separated (RS = 2.84, 2.58 and 3.58, respectively). By comparing the chromatograms of racemates and single enantiomers of the three intermediates, the e.e. values of the single enantiomers were determined and calculated.

A novel chiral stationary phase was prepared by bonding a novel β-cyclodextrin derivative on silica gel, and it was used for the separation of timolol in high efficiency liquid phase. In the reverse mode, the factors such as the proportion of chiral additives, flow rate, column temperature, repeatability and stability were investigated. The optimum chromatographic conditions are as follows: column temperature was 25°C, flow rate was 0.6 mL min(-1) and mobile phase was methanol-25 mM KH2PO4 (80/20, v/v). The chiral column has good reproducibility (Rs = 4.49, 4.51 and 4.40, respectively) and a certain degree of stability (Rs = 4.49, 3.01 and 0.72, respectively). This chiral stationary phase presented good chiral recognition performance toward timolol with good resolution (Rs = 4.49).

In recent years, the study of chiral compounds in vivo has received much attention. In this study, a novel method based on high performance liquid chromatography (HPLC) coupled with chemiluminescence (CL) detection was developed for the separation of tryptophan (Trp) enantiomers. o-Phthalaldehyde and N-acetyl-l-cysteine were used as chiral derivatization reagents for Trp before it can be detected by HPLC-CL method. The separation was carried out on an ODS column using a mobile phase composed of methanol-0.01mol/L phosphate buffer (40/60, v/v). Under the optimum conditions, satisfactory results were obtained, including complete separation, good relative standard deviations and low detection limits. The applicability of the proposed method has been validated by determining Trp in biological samples. Linear responses (r>0.9990) were observed over the range of 2.5×10(-7) to 1.2×10(-5)g/mL of Trp enantiomers, with quantitation limit of 2.5×10(-7)g/mL. The assay method shows good specificity to Trp enantiomers, and thus it will have great potential application in clinical diagnosis. The mean extraction efficiency of Trp enantiomers in mice plasma samples were 98.48% and 97.40%, respectively. The mean relative standard deviation (RSD) of Trp enantiomers were <3%.

In this study, functional isoleucine ionic liquids were synthesized and used as novel chiral ligands coordinated with Cu(ii) in chiral ligand exchange chromatography.

A new liquid chromatographic method has been developed for the chiral separation and quantitative determination of the enantiomers of ketoprofen. The enantiomers were separated by a Chiralpak IC (250×4.6 mm, 5 μm) at 25˚C and detected at 268 nm, and the mobile phase used was n-hexane-isopropanol (90/10, V/V; 0.1%TFA), with a flow rate of 0.8 mL·min -1 . The enantiomers of ketoprofen were separated and the resolution was 2.16. The content of ketoprofen sustained release capsules and enteric-coated capsules were 98.69%, 97.50%, respectively. By comparing the chromatograms(on Chiralcel OJ-H) of ketoprofen enantiomers and the first effluent on Chiralpak IC, it was determined that the first effluent was (S)-ketoprofen.

A novel cyclodextrin (CD) derivative mono(6A-N-allylamino-6A-deoxy)per-3-chlorine-4-methyl-phenylcarbamoylated-β-CD was synthesized and chemically immobilized onto the surface of γ-mercaptopropyl-functionalized silica gel step by step. The products were all purified and characterized and then got a substance with definitional structure. This chiral stationary phase (CSP) of 3-chlorine-4-methyl-phenylcarbamoylated-β-CD bonded on silica gel exhibited excellent separation capability for several chiral compounds in high-performance liquid chromatography. In the enantiomeric separations of five racemates with a mixture of methanol and aqueous KH2PO4 buffer as the mobile phase, this CSP presented good chiral recognition performance.