Amino-PEG5-alcohol

Amino-PEG5-alcohol is a PEG-based bifunctional linker designed for modular assembly in targeted protein degradation (PROTAC) workflows. Its flexible polyether backbone supports productive ternary complex formation, while the terminal amino and alcohol functionalities enable robust conjugation to ligands under standard bioconjugation and coupling strategies. This linker is well suited for constructing PROTACs where controlled spacing and aqueous compatibility are important, and the following sections describe its structure and practical reactivity for experimental use.

Structure: The linker comprises a flexible polyethylene glycol chain terminated by an amino group and a primary alcohol. It contains repeating ether linkages that confer conformational mobility and hydrophilicity, alongside a carbon–oxygen bond at the alcohol terminus. The amino functionality provides a reactive handle for amide or carbamate formation.

Reactivity: The amino group can be employed in amide coupling (via activated carboxylic acids) or carbamate formation (via activated carbonyl derivatives), while the alcohol can participate in esterification or conversion to leaving-group derivatives for subsequent substitution. Typical conditions use coupling reagents such as carbodiimides or activated chloroformates, with polar aprotic solvents and base to promote nucleophilic acyl substitution. Protecting-group strategies are often used to maintain chemoselectivity during stepwise PROTAC synthesis.