Enantioseparation of racemic aminoglutethimide using asynchronous simulated moving bed chromatography.

The separation of aminoglutethimide enantiomers by the continuous multicolumn chromatographic processes were investigated experimentally and theoretically, where the columns were packed with cellulose tris 3,5-dimethylphenyl-carbamate stationary phase (brand name Chiralcel OD) and mobile phase was a mixture of n-hexane and ethanol with monoethanolamine additive. The continuous enantioseparation processes included a synchronous shifting process (SMB) and an asynchronous shifting process (VARICOL), which allowed reducing the column number (here from six-column SMB to five-column VARICOL process). Transport-dispersive model with the consideration of both intraparticle mass transfer resistance and axial dispersion was adopted to design and optimize the operation conditions for the separation of aminoglutethimide enantiomers by SMB process and VARICOL process.

[Chromatographic separation of aminoglutethimide enantiomers on cellulose tris(3,5-dimethylphenylcarbamate) chiral stationary phase].

Aminoglutethimide (AG) has been used clinically as a drug in the treatment of hormone-dependent metastatic breast cancer. It was reported that S-(-)-AG enantiomer had small activity and sometimes might cause side effects. Therefore, it was of great significance to obtain the high-purity R-(+)-AG by enantioseparation.

Experiment and modeling for the separation of guaifenesin enantiomers using simulated moving bed and Varicol units.

The separation of guaifenesin enantiomers by both simulated moving bed (SMB) process and Varicol process was investigated experimentally and theoretically, where the columns were packed with cellulose tris 3,5-dimethylphenylcarbamate (Chiralcel OD) stationary phase and a mixture of n-hexane and ethanol was used as mobile phase. The operation conditions were designed based on the separation region with the consideration of mass transfer resistance and axial dispersion, and the experiments to separate guaifenesin enantiomers were carried out on VARICOL-Micro unit using SMB process with the column configuration of 1/2/2/1 and Varicol process with the column configuration of 1/1.5/1.

Experiment and modeling for the separation of trans-stilbene oxide enantiomers on Chiralcel OD preparative column.

The chromatographic enantioseparation of trans-stilbene oxide (TSO) was studied experimentally and theoretically, where the preparative column was packed with 20 μm Chiralcel OD stationary phase and hexanes/2-propanol were used as mobile phase. The bed porosity, axial dispersion coefficient, mass transfer coefficient and the column efficiency were determined according to the pulse response experiments. The adsorption equilibrium isotherms of single and racemic mixture of trans-stilbene oxide were measured by the frontal analysis, the linear-Langmuir isotherm model was used to fit the experimental data, and the relative parameters were estimated for the competitive adsorption equilibrium of TSO enantiomers.