(S,R,S)-AHPC-C2-NH2 dihydrochloride incorporates a VHL ligand for the E3 ubiquitin ligase, and a PROTAC linker. (S,R,S)-AHPC-OH can be used in the synthesis of a series of PROTACs.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.