Hydroxy-PEG3-MS

Hydroxy-PEG3-MS is a polyethylene glycol-based linker designed for modular assembly of PROTACs, enabling efficient spatial separation between a target-binding ligand and an E3 ligase recruiter. Its hydroxyl functionality supports robust synthetic handle formation, while the PEG segment contributes to conformational flexibility and improved aqueous compatibility, which can benefit ternary complex formation. The structure and reactivity considerations for PROTAC construction are described in detail below.

Structure: Hydroxy-PEG3-MS comprises a PEG-derived chain featuring ether linkages that impart flexibility and hydrophilicity. The terminal hydroxyl group provides a reactive site for derivatization, while the overall linker architecture supports stable, non-labile connectivity under typical organic synthesis conditions used in PROTAC workflows.

Reactivity: The hydroxyl terminus is suitable for conversion into activated intermediates used in PROTAC conjugation, following established hydroxyl derivatization strategies (e.g., formation of leaving-group or coupling-ready derivatives). Typical reactions are performed under anhydrous conditions with inert atmosphere when required, using standard amine- or carboxylate-coupling logic, and appropriate bases and compatible solvents to preserve linker integrity and minimize side reactions.