Propargyl-PEG4-5-nitrophenyl carbonate | CAS 1422540-81-5

Propargyl-PEG4-5-nitrophenyl carbonate is a PEGylated propargyl carbonate click chemistry reagent designed for bioorthogonal conjugation workflows. As a propargyl-bearing carbonate, it combines an alkynyl handle for copper-free or copper-assisted click labeling with a reactive carbonate leaving group that enables efficient functional group transfer to nucleophilic targets. The flexible PEG4 spacer and the nitrophenyl carbonate motif make it well-suited for building stable, low-fouling conjugates used in chemical biology, biomaterials modification, and molecular imaging probe preparation.

1. Surface And Material Functionalization

Propargyl-PEG4-5-nitrophenyl carbonate is widely used to introduce alkyne functionality onto polymeric and biomaterial surfaces where downstream click conjugation is required. Researchers apply it to functionalize surfaces that will later be decorated with azide-bearing ligands, affinity tags, or imaging reporters, leveraging the PEG spacer to improve accessibility of the reactive handle and reduce nonspecific interactions. This reagent is particularly valuable in workflows that require uniform installation of an alkynyl group while maintaining chemical stability during storage and handling of modified materials.

2. Biomolecule PEGylation And Labeling

Propargyl-PEG4-5-nitrophenyl carbonate supports conjugation strategies that install propargyl/alkyne groups onto biomolecules for subsequent click-based attachment of dyes, affinity reagents, or reporter constructs. The PEG4 linker helps preserve solubility and can reduce steric hindrance, which is important when preparing labeled proteins, peptides, or other biomolecular building blocks for analytical and discovery research. In typical lab practice, the reagent is selected when an alkyne handle must be introduced under conditions compatible with sensitive biomolecular formats and when a defined PEG spacer is desired for consistent labeling density and performance in downstream conjugation.

3. Molecular Imaging Probe Assembly

Propargyl-PEG4-5-nitrophenyl carbonate is used as a modular precursor for assembling alkyne-functional imaging probes and diagnostic reagents that are subsequently coupled to azide-containing reporter scaffolds. Teams in molecular imaging and chemical biology often rely on this reagent to generate alkynyl intermediates that can be rapidly diversified through click chemistry, enabling systematic variation of targeting motifs, fluorophores, or other signal-generating components. The PEG4 architecture contributes to probe solubility and helps maintain reagent reactivity during multistep labeling and purification workflows.

4. Linker Design For Targeted Conjugates

Propargyl-PEG4-5-nitrophenyl carbonate is commonly incorporated into linker design pipelines where a propargyl-bearing PEG spacer is needed to connect two functional modules via click chemistry. Researchers use it to prepare alkyne-bearing conjugation intermediates that can be paired with azide-functional partners such as targeting ligands, cell-binding peptides, or affinity tags, supporting rapid construction of multicomponent chemical tools. This approach is favored in research-grade reagent development because it separates the installation of the alkyne handle from the final assembly step, improving flexibility across parallel probe or material batches.