Propargyl-PEG2-beta-D-glucose

Propargyl-PEG2-beta-D-glucose is a PEG-based, sugar-functional linker designed to support modular PROTAC assembly through orthogonal “click” chemistry. Its flexible ethylene glycol spacer and β-D-glucose recognition motif help tune linker length, solubility, and the presentation of the reactive handle for efficient conjugation. This product is well suited for constructing targeted protein degradation probes, where robust, high-yield coupling strategies are essential; detailed structural and reactivity considerations are provided below.

Structure: The linker combines a propargyl terminal alkyne with a short polyethylene glycol spacer and a β-D-glucose moiety. It contains ether linkages within the PEG segment, a glycosidic linkage characteristic of β-D-glucose, and a carbon–carbon triple bond at the propargyl terminus. Overall, it is designed for aqueous compatibility and conformational flexibility.

Reactivity: The primary synthetic utility is the terminal alkyne for copper-catalyzed azide–alkyne cycloaddition, enabling efficient conjugation to azide-functional ligands used in PROTACs. Typical conditions employ a Cu(I) source generated in situ, an appropriate ligand stabilizer, and aqueous or mixed aqueous/organic solvents to maintain solubility. Reaction proceeds via cycloaddition to form a stable triazole linkage, with temperature and mixing optimized to preserve sensitive functional groups.