Superstructures with cyclodextrins: Chemistry and applications

Cyclodextrins (CDs) are cyclic oligosaccharides consisting of 1,4-glycosidically linked α-D-glucose units. Production of these compounds is accomplished by enzymatic degradation of starch using CD-glycosyl transferase. Since their discovery more than 100 years ago, a significant development in CD research has taken place. Various applications of CDs can be found, e.g. the binding of odors and flavors. Even drugs can be complexed and set free after a while by CDs. This enables the transfer of hydrophobic substances into aqueous media, which is of great interest in pharmaceutical chemistry. Regarding the interactions of CDs with low-molecular and macromolecular compounds, respectively, the reactivity of complexed molecules is another key factor besides solubility effects.

In organic synthesis and polymer chemistry, the interest in CDs has increased significantly during the past decades. For instance, in the latter case covalent attachment of CDs to macromolecules and threading of CD molecules onto suitable macromolecular chains could be demonstrated. Unlike other macrocycles such as crown ethers or calixarenes, the cavity of CDs is big enough to include more or less hydrophobic molecules completely.