Azido-PEG10-amine

Azido-PEG10-amine is a PEG-based linker bearing a terminal azide and a primary amine, designed to enable modular assembly of PROTACs through orthogonal conjugation handles. Its flexible, hydrophilic PEG segment can improve solubility and provide spatial separation between binding elements, while the azide and amine support widely used bio-conjugation chemistries. The following sections describe the linker’s structure and the practical reactivity considerations for PROTAC construction.

Structure: The molecule is a polyethylene glycol chain terminated with an azide functionality and a primary amine. It contains ether linkages along the PEG backbone and terminal nitrogen-containing groups, offering flexibility, polarity, and hydrogen-bonding capacity. The azide is a stable, electrophile-compatible handle for click-type transformations.

Reactivity: The terminal azide is well suited for copper-catalyzed azide–alkyne cycloaddition or related azide-based ligations, typically requiring an alkyne partner under standard click conditions. The primary amine enables amide-bond formation with activated carboxylic acids (for example, using coupling reagents) or reductive amination strategies with appropriate carbonyls. Reactions are commonly performed in polar organic or buffered aqueous media, with careful control of pH to maintain amine reactivity while preserving azide integrity.