t-Butyl ester-PEG4-CH2COOH

Description

t-Butyl ester-PEG4-CH2COOH is a PEG linker containing a t-butyl group with a terminal carboxylic acid. The terminal carboxylic acid can react with primary amine groups in the presence of activators e.g. HATU to form a stable amide bond. The hydrophilic PEG spacer increases solubility in aqueous media. The t-butyl group can be deprotected under acidic conditions.