Bromo-PEG3-acetic acid linker contains a bromide 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 bromide (Br) is a very good leaving group for nucleophilic substitution reactions.
Axispharm offers 3000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.