Axispharm offers you high purity (S,R,S)-AHPC-amido-C2-acid CAS:2172819-72-4 is a VHL ligand with a 2 carbon alkyl linker and a terminal acid for PROTAC compounds.
AxisPharm offers 5000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.