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Controlling the structure and reactivity of the chain-end group is a central objective in modern polymer chemistry. Here, we introduce 3,6-anhydrogalactal as a single-addition monomer that enables efficient and versatile chain-end functionalization of metathesis polymers. Readily synthesized from biomass-derived galactal, 3,6-anhydrogalactal exhibits excellent single-addition reactivity, allowing precise chain-end modifications even when introduced simultaneously with the propagating monomer. Theoretical calculations provide mechanistic insights into the unique reactivities governing its single-addition behavior. Its broad functional group compatibility facilitates diverse applications, including block copolymer synthesis, polymer-polymer coupling, and bioconjugation, demonstrating significant potential for advancing polymer materials and bioconjugation strategies.
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Chemoselective bioconjugation based on modular click chemistry with 4-halocoumarins and aryl sulfonates
We report chemoselective and modular peptide bioconjugation using stoichiometric amounts of 4-halocoumarin and arylsulfonate agents that undergo metal-free C(sp 2 )-heteroatom bond formation at micromolar concentrations. The underlying ipso -substitution click chemistry is irreversible and generates stable and inherently fluorescent bioconjugates, and the broad selection of coumarin tags offers high labeling flexibility and versatility. Different coumarins and arylsulfonates can be selectively attached to amino and thiol groups in the small peptides glutathione and ornipressin, and both free as well as latent thiols captured in disulfide bridges can be targeted if desired. The broad utility, ease of use, storage, and preparation of 4-halocoumarins and arylsulfonates are very attractive features that extend currently available dual bioconjugation capabilities.
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- Award ID(s):
- 1764135
- PAR ID:
- 10233077
- Date Published:
- Journal Name:
- RSC Advances
- Volume:
- 11
- Issue:
- 31
- ISSN:
- 2046-2069
- Page Range / eLocation ID:
- 18960 to 18965
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D1RA03271B
