N3-PEG3-CH2CH2COOH a PEG-based PROTAC linker can be used in the synthesis of BI-3663 (HY-111546), BI-4216 and BI-0319. Azido-PEG3-acid is also a non-cleavable 3 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs).In Vitro: 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.