Linker

The length and composition of the linker play critical roles in the physicochemical properties and bioactivity of PROTACs. While linker design has historically received limited attention, the PROTAC field is evolving rapidly and undergoing an important shift from synthetically tractable alkyl and polyethylene glycol to more sophisticated functional linkers. Equally important, linker-mediated binding cooperativity also represents a potential source of affinity for the POI for PROTACs based on weak affinity warheads. However, the current consensus is that the linker composition, and particularly its length and attachment point to the anchor/warhead, must be optimized for each ligand pair.