Kinetics of Strain-Promoted Alkyne-Nitrone Cycloadditions (SPANC) with Unprotected Carbohydrate Scaffolded Nitrones
Nathan Noël1, Agathe Martinez1, Fabien Massicot1
1Université de Reims Champagne-Ardenne, CNRS UMR 7312, ICMR, 51687 Reims, France.
Abstract:
The use of unprotected carbohydrate-derived nitrones as partners in strain-promoted alkyne-nitrone cycloadditions was investigated as a new tool for bioconjugation. The observed second-order reactions displayed rate constants of 3.4 × 10-4-5.8 × 10-2 M-1 s-1, which is the common order of magnitude of reaction kinetics with other simple aliphatic or aromatic nitrones. Applicability of this method to aqueous media was demonstrated by performing a one-pot protocol, which combines sequential formation of the nitrone and cycloaddition with cyclooctyne in water.
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