Hydroxy-PEG9-t-butyl ester

Hydroxy-PEG9-t-butyl ester is a PEG linker containing a hydroxyl group with a t-butyl ester. 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.