Azido-PEG8-alcohol

Azido-PEG8-alcohol is a polyethylene glycol-based linker bearing a terminal azide and a hydroxyl group, designed to facilitate modular assembly of PROTACs through bioorthogonal conjugation. Its flexible PEG scaffold helps tune linker length and solubility, while the azide handle enables efficient attachment to complementary targeting or E3-ligand fragments under mild conditions. The subsequent points describe its structure and practical reactivity considerations for PROTAC synthesis.

Structure: The molecule comprises a PEG chain terminated by an azide functionality and a primary alcohol, providing a flexible, ether-rich backbone. It contains ether linkages along the PEG segment and a terminal organic azide, with polar heteroatoms that support solubility and conformational adaptability in linker design.

Reactivity: The terminal azide is suitable for copper-catalyzed azide–alkyne cycloaddition or strain-promoted azide–alkyne cycloaddition, enabling rapid formation of stable triazole linkages to alkyne-bearing partners. For PROTAC construction, conjugation is typically performed under mild, anhydrous-to-humid conditions compatible with sensitive ligands, using appropriate catalysts or catalyst-free setups, with solvents commonly selected to dissolve both coupling partners and preserve functional group integrity.