Propargyl-PEG2-Tos is a PEG linker containing a tosyl group and a propargyl group. The hydrophilic PEG spacer increases solubility in aqueous media. The tosyl group is a very good leaving group for nucleophilic substitution reactions. The propargyl group can react with azide-bearing compounds or biomolecules via copper catalyzed azide-alkyne Click Chemistry to yield a stable triazole linkage.
