5-(2,5-Dioxo-2,5-dihydro-1H-pyrrol-1-yl)pentanoic acid contains a maleimide group and 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 maleimide group reacts specifically with a thiol group to form a covalent C-S bond, enabling the bioconjugation with a thiol bearing molecules.
Axispharm offers 3000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.