Amino-PEG5-t-butyl ester

Amino-PEG5-t-butyl ester is a PEG molecule consisting of an amino group and a t-butyl protected carboxyl group. The amino group is reactive with carboxylic acids, activated NHS esters, carbonyls (ketone, aldehyde) etc. The t-butyl protected carboxyl group can be deprotected under acidic conditions.The hydrophilic PEG spacer increases solubility in aqueous media.

This heterobifunctional, PEGylated crosslinker features an amino group at one end and t-butyl-protected carboxyl group at the other, which can be deprotected with acidic conditions. The hydrophillic PEG linker facilitates solubility in biological applications. Amino-PEG5-t-butyl ester can be used for bioconjugation or as a building block for synthesis of small molecules, conjugates of small molecules and/or biomolecules, or other tool compounds for chemical biology and medicinal chemistry that require ligation. Examples of applications include its synthetic incorporation into antibody-drug conjugates or proteolysis-targeting chimeras (PROTAC^? molecules) for targeted protein degradation.