Benzyl-PEG4-CH2CO2tBu linker contains a benzyl group and a t-butyl ester group. Both the benzyl and t-Butyl group can be removed under acidic conditions. The carboxylic acid readily reacts with primary and secondary amines in the presence of EDC, DCC or HATU to form amide bonds. The hydrophilic PEG spacer increases the solubility of the compound in aqueous media.
Axispharm offers 3000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.