T-Boc-N-amido-PEG4-Val-Cit

T-Boc-N-amido-PEG4-Val-Cit is a protease-cleavable ADC linker, featuring a Boc-protected amine, a hydrophilic PEG spacer, and a Val-Cit dipeptide. The Val-Cit dipeptide is susceptible to cleavage by cellular proteases and contains a free carboxylic acid that can couple with amines to form amides. The Boc group can be removed under acidic conditions to reveal a free primary amine, which is useful for various reactions, such as conjugation or reductive amination.