Azido-PEG2-alcohol

This Azido-PEG2-alcohol linker is designed for modular PROTAC assembly, providing a flexible polyethylene glycol spacer terminated with a reactive azide handle. Its ether-rich PEG character supports solubility and conformational adaptability, while the azide enables efficient bioorthogonal conjugation strategies commonly used to connect ligands and warheads. The combination of a hydrophilic linker segment and a chemically versatile functional group makes it well suited for constructing targeted protein degraders, as described in detail below.

Structure: The linker contains a terminal azide functional group and an alcohol at the opposite end, connected through a short polyethylene glycol chain. It features ether linkages within the PEG segment and a primary alcohol capable of hydrogen bonding, contributing to favorable aqueous compatibility and flexible spacing.

Reactivity: The azide group supports established azide-based conjugation chemistry, including copper-catalyzed azide–alkyne cycloaddition and azide–alkene cycloaddition variants, enabling ligand coupling under conditions compatible with many organic functional groups. The alcohol end can be converted to activated derivatives (for example, via standard esterification or carbonate formation) for subsequent amide or ether bond formation. Typical workflows employ polar aprotic solvents and inert atmosphere to preserve azide integrity.