Azido-PEG4-tetra-Ac-beta-D-glucose

Azido-PEG4-tetra-Ac-beta-D-glucose is a PEG-based, azide-functional linker building block designed for modular construction of PROTACs and related targeted degradation conjugates. Its poly(ethylene glycol) segment supports aqueous solubility and conformational flexibility, while the azide handle enables efficient bioorthogonal coupling to complementary partners. The glycosylated, acylated glucose motif can help tune polarity and steric presentation at the linker–warhead interface. Detailed structure and reactivity considerations are provided below.

Structure: The linker contains an azide functional group attached to a PEG chain, providing a flexible ether-rich scaffold. Multiple acylated hydroxyl substituents on a beta-D-glucose core contribute to increased hydrogen-bonding capacity and defined stereochemistry. Overall, it is an organic conjugate with ether and ester linkages.

Reactivity: The azide group is well suited for copper-catalyzed or strain-promoted azide–alkyne cycloaddition, enabling attachment to alkyne-bearing ligands under standard click-chemistry conditions. For PROTAC assembly, use compatible solvents such as aqueous alcohol mixtures or polar aprotic media, and select catalysts and additives that preserve sensitive binding elements. Mechanistically, cycloaddition forms a stable triazole linkage, minimizing linker cleavage during subsequent conjugate handling.