Credit: © 2008 ACS

An important step in the process of bacterial infection involves the adhesion of the bacteria onto the host tissue. For certain bacteria, this occurs through the binding of their hair-like appendages to mannose sugars on the host's surface. Molecules that contain a mannose residue can, therefore, be used block the binding and inhibit adhesion.

To investigate the design of more efficient and specific inhibitors, René Roy and co-workers at the University of Québec in Montreal have devised1 a synthetic route for making versatile dendritic architectures onto which mannose and other sugars can be easily attached. Their approach uses a coupling reaction between thioacetylated cores and TRIS derivatives to produce a dendritic scaffold. A mannopyranoside — a sugar derivative — is then attached to each branch through a Cu(I)-catalysed cycloaddition reaction. Depending on the choice of reactants used in the scaffold synthesis, dendrimers with either 12 or 18 mannose residues were formed.

The reactions involved were quick, simple and high-yielding. Higher-generation dendritic structures are now being investigated by Roy and co-workers, and biological studies will be undertaken to investigate the therapeutic potential of the various compounds.