N-(Propargyl-PEG2)-N-Boc-PEG3-t-butyl ester | CAS 2093152-78-2

N-(Propargyl-PEG2)-N-Boc-PEG3-t-butyl ester is a PEG-based propargylated click chemistry reagent designed for copper(I)-catalyzed azide–alkyne cycloaddition (CuAAC) workflows. Its structure combines a terminal alkyne handle for bioorthogonal conjugation with a multi-PEG architecture that improves aqueous compatibility and spacing between functional groups. The Boc-protected and t-butyl ester motif supports downstream deprotection strategies commonly used to generate reactive termini for polymer, surface, and biomolecule conjugation platforms.

1. PEGylated Probe Conjugation

N-(Propargyl-PEG2)-N-Boc-PEG3-t-butyl ester is widely used as a click-ready PEG linker for assembling fluorescent, affinity, or mass-tagged probes by CuAAC coupling to azide-bearing partners. Researchers in chemical biology and molecular imaging frequently select this reagent to introduce a flexible PEG spacer that reduces steric congestion at the labeling site and helps maintain probe accessibility on proteins, peptides, or polymeric carriers. The propargylated end provides a reliable alkyne handle for modular probe construction, while the PEG3 segment supports improved solubility and more uniform conjugate behavior in aqueous labeling buffers.

2. Surface And Material Functionalization

N-(Propargyl-PEG2)-N-Boc-PEG3-t-butyl ester supports the preparation of functional polymer surfaces and biomaterial coatings where controlled attachment of azide-functional components is required. Materials scientists and biomaterials groups use this type of PEG–alkyne linker to incorporate reactive spacing layers that can mitigate nonspecific interactions and improve mass transport to immobilized ligands. After appropriate activation/deprotection steps, the reagent’s ester functionality can be leveraged for integration into polymer networks or for generating stable anchoring points, while the alkyne enables straightforward CuAAC attachment of imaging handles, capture ligands, or cell-interaction motifs to the material surface.

3. Biomolecule Labeling Workflows

N-(Propargyl-PEG2)-N-Boc-PEG3-t-butyl ester is commonly incorporated into bioconjugation pipelines to generate azide-reactive conjugates for labeling glycans, biomolecular scaffolds, or engineered macromolecules that present azide groups. In molecular imaging and diagnostic reagent development, PEG spacers are often used to tune conjugate hydrophilicity and to preserve binding-site accessibility after labeling, especially when multiple modifications are introduced. The reagent’s propargyl alkyne provides a convenient coupling site for CuAAC-based assembly, enabling consistent generation of conjugates used as research tools for tracking, enrichment, or analytical readouts.

4. Polymer and Nanoconjugate Assembly

N-(Propargyl-PEG2)-N-Boc-PEG3-t-butyl ester is well suited for constructing PEGylated polymer conjugates and nanoconjugates where modular click chemistry is needed to decorate carriers with defined functional groups. Polymer chemistry and chemical biology teams use the PEG-rich architecture to improve colloidal stability and to create a controllable distance between the carrier backbone and the attached moieties introduced via azide partners. The terminal alkyne facilitates efficient CuAAC assembly into multi-component constructs, including PEGylated linkers for reagent libraries, imaging scaffolds, and structured materials used in analytical and translational research settings.