TCO-PEG4-DBCO is a PEG-based PROTAC linker can be used in the synthesis of PROTACs. TCO-PEG4-DBCO is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].
PROTACs contain two different ligands connected by a linker; one is a ligand for an E3 ubiquitin ligase and the other is for the target protein. PROTACs exploit the intracellular ubiquitin-proteasome system to selectively degrade target proteins.
ADCs are comprised of an antibody to which is attached an ADC cytotoxin through an ADC linker.
[1]. Rahim MK, et al. Enhancing reactivity for bioorthogonal pretargeting by unmasking antibody-conjugated trans-cyclooctenes. Bioconjug Chem. 2015 Feb 18;26(2):352-60.