Synthetic Methods to Prepare Amphiphilic and Biocompatible Cyclodextrin Derivatives

摘要

Cyclodextrin (CD) alkylation is commonly accomplished via alkyl halide reagents, using sodium hydride (NaH) 1 . Since complete drying of the solvents dimethyl formamide (DMF), tetrahydrofuran (THF), and dimethyl sulfoxide (DMSO) is difficult, and NaH is unstable even in the presence of trace moisture, synthetic routes utilizing NaH demand significant precautions. Additionally, NaH is a strong reducing agent, which can cause random ionization of hydroxyl groups. These processes involved a multiple-step work-up procedure to obtain products in pure state2 . In one method3 the oxyanions of β-CD were prepared with aqueous NaOH of concentrations up to 30%. High NaOH concentrations, and subsequent strong acid neutralization, can affect the stability of oligomeric CD chains. Here, we report a simple route for the synthesis of octyl or hydroxyoctyl modified α- and β-CD’s. It is a simple one-pot method, not involving sodium hydride as a reagent or requiring subsequent strong acid neutralization. The products are easily stored as dry powders, and are insensitive to ambient moisture.