Title of article :
Steric effects on the enantiodiscrimination of diproline chiral stationary phases in the resolution of racemic compounds
Author/Authors :
Dai، نويسنده , , Zhi and Ye، نويسنده , , Guozhong and Pittman Jr.، نويسنده , , Charles U. and Li، نويسنده , , Tingyu، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2011
Abstract :
Eight diproline chiral stationary phases with different end-capping groups were prepared and evaluated for the enantio-selective resolution of 41 racemic analytes. The end-capping group on the N-terminal of the peptide proved to be important as the chiral separation efficiency was decreased significantly without it. In general, increasing steric bulkiness near the N-terminal of diproline increases the enantioselectivity. Electronic structures of the end-capping groups are also important. One stationary phase with an adamantanecarbonyl capping group was found to provide both higher average separation and resolution factors than our previous leader. Three other stationary phases with 2-methylpropanoyl, cyclopropanecarbonyl and cyclobutanecarbonyl end capping groups were found to provide comparable average separation factor but higher resolution factors than our previous leader.
Keywords :
Steric effect , Proline chiral stationary phase , proline , Peptide stationary phase , Proline enantioselective stationary phase
Journal title :
Journal of Chromatography A
Journal title :
Journal of Chromatography A