169751-72-8

Hydroxy-PEG4-CH2CO2tBu is a PEG linker containing a hydroxyl group with a t-butyl protected carboxyl group. The hydrophilic PEG spacer increases solubility in aqueous media. The hydroxyl group enables further derivatization or replacement with other reactive functional groups. The t-butyl protected carboxyl group can be deprotected under acidic conditions.