Preparation Of Ionic Liquid Functionalized β-cyclodextrin Stationary Phase And Its Chiral Separation Of Amino Acid Schiff Base

Amino acid Schiff bases are a class of compounds obtained by dehydration and condensation of amino acids and different aldehydes.They are an important chiral compound,and its application in analytical chemistry,medicine,food,catalysis,metal anticorrosion and other fields is very prominent.However,one of the chiral compounds is often biologically active,while the other is less biologically active or may be ineffective,or even has toxic side effects.Therefore,it is very necessary to obtain a single isomer of chiral compounds.Cyclodextrin is a macrocyclic compound with a certain pore size and "internally hydrophobic and externally hydrophilic".Its special structural characteristics make it widely used in the field of chiral compound separation.One of the main applications is to bond cyclodextrin derivatives to silica gel to prepare a stationary phase,and to separate chiral substances on a high performance liquid chromatograph.In this experiment,based on the synthesis of a variety of amino acid Schiff bases with different configurations,three ionic liquids N-methylimidazole,4-amino-1,2,4-triazole and 4-(4-Hydroxybenzimide)-1,2,4-triazole derivatized β-cyclodextrin compound,and bonded to silica gel to prepare three stationary phases.The separation of chiral amino acid Schiff base compounds was carried out in reversed phase mode and polar organic phase mode,and the antibacterial properties of some of the enantiomers were tested.The main experimental contents are as follows:1.Use D/L-tyrosine,D/L-aspartic acid and D/L-glutamic acid with salicylaldehyde,furfural,p-nitrobenzaldehyde,p-hydroxybenzaldehyde,p-chlorobenzaldehyde,5-Nitrosalicylic aldehyde and p-dimethylaminobenzaldehyde were dehydrated and condensed to prepare 36 Schiff bases.Their structures were characterized by Fourier infrared spectroscopy and proton nuclear magnetic resonance spectroscopy.2.Using 6-p-toluenesulfonyl-β-CD as the intermediate,N-methylimidazole,4-amino-1,2,4-triazole and 4-(4-hydroxybenzimide)-1,2,4-Triazole is an ionic liquid,and three ionic liquid functionalized cyclodextrin compounds have been prepared.Secondly,the5μm spherical silica gel was bonded to the macrocyclic compound by the silane coupling agent KH-560,and three chiral stationary phases were prepared,and the melting point and infrared test of the involved compounds were carried out.The product was loaded into a250mm*4.6mm(i.d.)chromatographic column by homogenization method,and three chromatographic columns CSP1,CSP2,CSP3 were obtained.3.The separation performance of the chromatographic columns CSP1,CSP2,CSP3 was tested using the chiral amino acid Schiff base compound prepared in this experiment under the reversed-phase interaction mode and the polar organic mode.The experimental results show that in the two modes of action,the three chromatographic columns have basically achieved baseline separation.In the polar organic mode of action,the resolution of CSP3 for compounds 1/7,14/18,and 13/17 reached more than 4.0,and the separation performance was excellent.4.The chiral amino acid Schiff base compound prepared in this paper was tested for its antibacterial performance using Escherichia coli and Staphylococcus aureus.The experimental results show that the different configurations of amino acid Schiff bases synthesized in this experiment have different inhibitory effects on the growth of the above two bacterial species.