t-butyoxycarboxy-PEG4-phosphonic acid ethyl ester contains a t-Butyl ester group and a phosphonic acid ethyl ester moiety. The t-butyl group is removed under acidic conditions. Ethyl phosphonate can be used in surface modifications. The hydrophilic PEG linker can increase the water solubility of the compound in aqueous media.
AxisPharm offers 4000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.