Propargyl-PEG4-(CH2)3-acid contains a propargyl group with a terminal carboxylic acid. The terminal carboxylic acid readily reacts with primary and secondary amine under EDC, DCC, HATU or other amide coupling conditions to form a stable amide bond. The PEG spacer increases the aqueous solubility of the resulting compound. The propargyl group can be reacted with azide-bearing compounds or biomolecules via copper catalyzed Click Chemistry to form a stable triazole linkage.
AxisPharm offers 4000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.