Acetic acid, [2-(phenylmethoxy)ethoxy]-

Benzyl-PEG2-CH2CO2H is a PEG linker with a benzyl protecting group and a terminal carboxylic acid. The terminal carboxylic acid can react with primary amine groups in the presence of activators (e.g. EDC, or HATU) to form a stable amide bond. The benzyl protecting group can be removed via hydrogenolysis. The hydrophilic PEG linker increases the water solubility of the compound.