Synthesis of Amino Acid Derived β-Cyclodextrins Used in Chiral Separation by Capillary Electrophoresis

Six new kinds of amino acid derived β-cyclodextrins were synthesized to improve their water solubility and chiral separation properties. They are heptakis2,6-di-O-3-L-（1-isopropyl carboxyl methyl amino）-2-（hydroxy） propyl-β-cyclodextrin （i.e. L-Val-β-CD）, heptakis2,6-di-O-3-L-（1-benzyl carboxyl methyl amino）-2-hydroxy propyl-β-cyclodextrin （i.e. L-Phe-β-CD）, heptakis2,6-di-O-3-（D, L-1-benzyl carboxyl methyl amino）-2-hydroxy propyl-β-cyclodextrin （i.e. D,L-Phe-β-CD）, heptakis2,6-di-O-3-（L-1-hydroxymethyl carboxyl methyl amino）-2-hydroxy propyl-β-cyclodextrin （i.e. L-Ser-β-CD）, heptakis2,6-di-O-3-（L-1-carboxylmethyl carboxyl methyl amino）- 2-hydroxy propyl-β-cyclodextrin （i.e. L-Asp-β-CD）, heptakis2,6-di-O-3-（L-2-carboxyl tetramethylene amino）-2-hydroxy propyl-β-cyclodextrin （i.e. L-Pro-β-CD）. Their chemical structures were certified using FTIR and （）¹H NMR. Except for L-Phe-β-CD and D,L-Phe-β-CD, that are in soluble in water, the other amino acid derived β-CDs all have good water solubility. D,L-tyrosine and promethazine were baselinely separated by L-Val-β-CD in capillary electrophoresis.