Thalidomide-O-PEG2-propargyl (E3 ligase Ligand-Linker Conjugates 32) is a synthesized E3 ligase ligand-linker conjugate that incorporates the Thalidomide based cereblon ligand and 2-unit PEG linker used in PROTAC technology[1]. Thalidomide-O-PEG2-propargyl is a click chemistry reagent, it contains an Alkyne group and can undergo copper-catalyzed azide-alkyne cycloaddition (CuAAc) with molecules containing Azide groups.