O-(2-Azidoethyl)-O-[2-(diglycolyl-amino)ethyl]heptaethylene glycol

This PROTAC linker is designed to provide a flexible, water-compatible spacer architecture that connects two bioactive ligands through stable ether linkages. Its heptaethylene glycol segment and aminoethyl diglycolyl motif help maintain solubility and conformational adaptability, which are valuable for tuning ternary complex formation in targeted protein degradation. The detailed Structure and Reactivity parameters are provided below.

Structure: The linker contains multiple ethylene glycol repeat units, an internal diglycolyl-aminoethyl segment, and terminal ether-linked azide functionality. It features ether bonds and amide connectivity within the diglycolyl region, with a polyether backbone that confers hydrophilicity and conformational flexibility.

Reactivity: The azide handle enables copper-free or copper-catalyzed azide–alkyne cycloaddition for modular PROTAC assembly, while preserving the ether-rich spacer. Typical strategies use an alkyne-bearing ligand under mild conditions in polar solvents compatible with polyether solubility. Reaction progress is monitored by disappearance of azide signals, and purification removes residual catalysts or reagents.