N-(Mal-PEG8-carbonyl)-N-bis(PEG8-t-butyl ester)
N-(Mal-PEG8-carbonyl)-N-bis(PEG8-t-butyl ester) is a trifunctional PEG linker containing two t-butyl esters and a maleimide joined together at a tertiary amide. Maleimide is a thiol-specific covalent ligand, often used for labeling cysteine residues along proteins. The two t-butyl esters can be deprotected to allow for reaction with amines or alcohols to form amides and esters respectively. The tertiary amide increases aqueous solubility through hydrogen bonding effects.