This Account reviews the synthesis, conformations, and supramolecular properties of calixarenes endowed with alpha-amino acids or peptides (Peptidocalixarenes) and carbohydrate units (Glycocalixarenes), with a major emphasis on calixarenes functionalized on the aromatic nuclei (upper or wide rim). Most properties of N-linked peptidocalixarenes are found to be quite different from those of the corresponding C-linked derivatives. An interesting example is the tendency of C-linked peptidocalixarenes to form self-assembled nanotubes in the solid state. In several cases the hydrogen bonding donor and acceptor groups of the amino acid residues and the cavity of cone calixarenes act cooperatively in guest binding in nonpolar solvents but not in water, where hydrophobic interactions dominate. Upper-rim bridged peptidocalixarenes act as vancomycin mimics being able to bind D-alanyl-D-alanine (D-Ala-D-Ala) residues. Glycocalixarenes show the phenomenon of multivalency in their binding to specific lectins, and those bearing thiourea spacers between the calixarene scaffold and the sugar units are able to bind aromatic carboxylates and phosphates, making them attractive as novel site specific drug delivery systems.
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.