m-PEG10-Tos

m-PEG10-Tos, provides a polyethylene glycol based spacer bearing a tosylate leaving group, enabling efficient formation of PROTAC conjugates through controlled nucleophilic substitution. Its PEG character supports solubility and conformational flexibility, which can improve productive engagement of target-binding ligands in targeted protein degradation workflows. The following sections describe the linker’s structural features and the practical reactivity considerations used during PROTAC assembly.

Structure: m-PEG10-Tos is a PEG-linked aromatic tosylate featuring an aryl sulfonate ester. The molecule contains ether linkages within the PEG chain and a tosylate group that serves as a reactive electrophile. These elements confer hydrophilicity, flexibility, and a stable, well-defined leaving group for conjugation.

Reactivity: Tosylate functionality is typically used in PROTAC synthesis via nucleophilic substitution, where an appropriate nucleophile (commonly an amine or related functional group on a ligand) displaces the tosylate. Reactions are generally performed under anhydrous or moisture-controlled conditions in polar aprotic solvents, with bases to promote nucleophile activation. The mechanism proceeds through an SN2-like displacement, and reaction monitoring is recommended to ensure complete conversion and minimize side reactions.