Sequence-Controlled Glycopolymers via Step-Growth Polymerization of Precision Glycomacromolecules for Lectin Receptor Clustering

A versatile approach for the synthesis of sequence-controlled multiblock copolymers, using a combination of solid phase synthesis and step-growth polymerization by photoinduced thiol-ene coupling (TEC) is presented. Following this strategy, a series of sequence-controlled glycopolymers is derived from the polymerization of a hydrophilic spacer macromonomer and different glycomacro-monomers bearing between one to five alpha-D-Mannose (Man) ligands. Through the solid phase assembly of the macro Yom., Effective Receptor Clustering monomers, the number and positioning of spacer and sugar moieties is controlled and translates into the sequence-control of the final polymer. A maximum M-n of 16 kDa, corresponding to a X-n of 10, for the applied macromonomers is accessible with optimized polymerization conditions. The binding behavior of the resulting multiblock glycopolymers toward the model lectin Concanavalin A (ConA) is studied via turbidity assays and surface plasmon resonance (SPR) measurements, comparing the ability of precision glycomacromolecules and glycopolymers to bind to and cross-link ConA in dependence of the number of sugar moieties and/overall molecular weight. The results show that there is a clear correlation between number of Man ligands and Con A binding and clustering, whereas the length of the glycooligomeror polymer backbone seems to have no effect.