mPEG6-alcohol

mPEG6-alcohol is a polyethylene glycol methyl ether (mPEG) end-functionalized with a terminal hydroxyl group, designed as a flexible, hydrophilic linker component for PROTAC synthesis workflows. Its ether-rich chain can enhance solubility and compatibility with common coupling chemistries, supporting the preparation of PROTAC constructs that require controlled linker architecture. The subsequent sections describe the structure and the practical reactivity considerations for assembling PROTACs with this linker.

Structure: The molecule comprises an mPEG ether backbone terminated by a primary alcohol, featuring repeating ethylene glycol units connected through ether linkages. This confers a polar, hydrogen-bonding-capable surface, with a terminal hydroxyl suitable for derivatization. The flexible, non-ionic chain supports conformational mobility and improved aqueous compatibility.

Reactivity: The terminal hydroxyl enables standard functional-group interconversions used in PROTAC assembly, including activation to alkylating or acylating intermediates followed by nucleophilic substitution or ester/amide bond formation. Typical approaches rely on coupling reagents and base-mediated conditions compatible with PEG chains, often using polar aprotic solvents to maintain solubility. Reaction design should account for PEG’s ether stability and minimize harsh, strongly oxidizing conditions that could degrade sensitive motifs.