Direct Chiral Separation of Four Indole Derivatives by High Performance Liquid Chromatography with Chiral Stationary Phase

A chiral stationary phase (CSP) was prepared by coating cellulose-tris(3,5-dimethylphenyl carbamate) (CDMPC) onto spherical silica gel. Four newly synthesized chiral indole derivatives were directly resolved on the CDMPC-CSP by a normal-phase system. The influences of structure and proportion of the alcohol in mobile phases on the separation by high-performance liquid chromatography with chiral stationary phase (HPLC) were investigated to optimize the chromatographic conditions. N-butano1, ethanol and ethanol were suitable for the separation of sample I, III, and IV as the modifiers, respectively, whereas the mixture of ethanol and n-propanol was suitable for sample I. Under the optimal conditions, excellent enantioseparation was achieved and the enantiomer excess values of all the four samples were determined. The satisfactory results indicated that the method of HPLC is ideal for the separation of indole derivatives.