Aminooxy-PEG1-propargyl

Aminooxy-PEG1-propargyl is a bifunctional PEG-based linker designed for modular PROTAC assembly, enabling efficient conjugation between targeting ligands and other functional handles. Its combination of an aminooxy group and a terminal propargyl (alkyne) handle supports orthogonal coupling strategies that are widely used to generate well-defined heterobifunctional degraders. The flexible ether-rich segment can improve solubility and reduce steric mismatch, facilitating reliable synthesis and subsequent evaluation in targeted protein degradation workflows.

Structure: The linker contains an aminooxy functional group connected through a short polyethylene glycol ether segment to a terminal propargyl alkyne. It features ether linkages, an oxime-reactive aminooxy moiety, and a carbon–carbon triple bond suitable for click-type chemistry. Overall polarity and flexibility are consistent with PEG-mediated solubility enhancement.

Reactivity: The aminooxy group is commonly used to form oxime linkages with carbonyl-containing partners under mild conditions, typically using aqueous or mixed aqueous buffers with an aniline or other mild catalyst when appropriate. The terminal alkyne enables copper-catalyzed azide–alkyne cycloaddition or related alkyne click reactions. Solvent systems are selected to maintain ligand integrity and compatibility with copper catalysis, while protecting groups are used when necessary to preserve reactive functionalities during PROTAC synthesis.