signal ratio can be used for enantiomeric excess (ee) analysis within linear range. However, CD detection often requires a high sample concentration where deviations from Beer's law may occur. Individual enantiomers of four chiral compounds were separated from commercial racemates by semipreparative high‐performance liquidchromatography (HPLC) with chiral columns. They were used to trace possible deviations
Stereoselectivedegradation of Diclofop‐methyl (DM) has been found in alcoholfermentation of grape must and sucrose solution with dry yeast. A method was developed for separation and determination the two enantiomers of DM during the fermentationprocess by high‐performance liquid chromatography based on cellulose tri‐(3,5‐dimethylphenyl‐carbamate) chiral stationary phase. The results showed that