Bromo-PEG4-acid linker contains a bromide group and a terminal carboxylic acid. The PEG spacer increases the aqueous solubility of the resulting compound. The bromide (Br) is a very good leaving group for nucleophilic substitution reactions. 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.
Axispharm offers 3000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.