The Synthesis Of Cyclodextrin Deriatives With Biological Functional Groups

Biological functional groups (sugars, amino acids, peptides, etc.) can be recognized by glycoproteins. The biological functional groups attach to cyclodextrins (CDs) can be applied as targeting drug delivery system. They carry drugs toward the specific biological receptors through the interactions between glycoproteins and special glycoside ligands on the CDs.This thesis research is divided into two parts:1. Synthesis of cysteine modified CD derivativesFirst, we synthesized the hexaki(6-O-allyl-2,3-di-O-benzyl)-a-CD, then grafted the N-acetyl-L-cysteine methyl ester to hexaki(6-O-allyl-2,3-di-O-benzyl)-a-CD by photoinduced of thiol-ene coupling, and debenzylated to give L-cysteine derivatives of a-CD. And then we expanded the thiol-ene couping reaction, there was not much influence the result of the reaction when the thiol contains the free carboxyl, but if it contained the free amino, it produced a series of by-products. And when the free amino was protected, the results were satisfactory. The alkene contained the free hydroxy, the thiol-ene couping reaction would proceed smoothly.2. Synthesis of glycosyl substituted cyclodextrin derivatives 2,3,4-tri-acetyl-l-thiol-(3-L-fucose were added to hexaki(6-O-allyl-2,3-di-O-benzyl)-a-CD by thiol-ene couping reaction, then debenzylated and deacetylated to give the per-glycosyl modified cyclodextrin derivatives.2,3,4-tri-acetyl-1-(3-L-fucosyl isothiocyanate were grafted to hexaki(6-deoxy-(N-aminoethyl)-amino)-α-CD by thiourea groups, and deacetylated to give the per-fucosyl substituted CD derivatives.This paper focuses on the photoinduced of thiol-ene coupling reaction to add the amino acids, and glycosyl mercaptan to CDs efficiently, with mild reaction conditions, and has certain applicability for different substrates. The synthetic amino acid and glycosyl modified CDs can be used as targetable drug carriers.