Propargyl-PEG8-NH2 (compound 3b) is a PEG-based PROTAC linker can be used in the synthesis of PROTACs. Propargyl-PEG8-NH2 is a non-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]. Genady AR, et al. Preparation and Evaluation of Radiolabeled Antibody Recruiting Small Molecules That TargetProstate-Specific Membrane Antigen for Combined Radiotherapy and Immunotherapy. J Med Chem. 2016 Mar 24;59(6):2660-73.