t-Boc-N-Amido-PEG5-Azid contains an azide group and Boc-protected amino group. The PEG spacer increases the aqueous solubility of the resulting compound. The azide group can react with alkyne, BCN, DBCO via Click Chemistry to afford a stable triazole linkage. The Boc group can be deprotected under mild acidic conditions to form a free amine, which can undergo amide coupling with carboxylic acid bearing biomolecules.
Axispharm offers 3000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.