Azido-PEG4-CH2COOH contains an azide group and a terminal carboxylic acid group. The azide group can react with alkyne, BCN, DBCO via Click Chemistry to yield a stable triazole linkage. 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.
AxisPharm offers 5000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.