Hydroxy-PEG20-t-butyl ester linker contains a hydroxyl group with a t-butyl ester. The PEG spacer increases the aqueous solubility of the resulting compound. The hydroxyl group can be derivatized to other reactive functional groups. The t-butyl protected carboxyl group can be deprotected under acidic conditions.
AxisPharm offers 4000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.