(1R,4R)-Thalidomide-2,5-diazabicyclo[2.2.1]heptane-(1R,4r)-cyclohexane-NH-Boc is a conjugate of E3 ligase ligand and linker , consisting of Thalidomide and the corresponding Linker. (1R,4R)-Thalidomide-2,5-diazabicyclo[2.2.1]heptane-(1R,4r)-cyclohexane-NH-Boc can serve as a Cereblon ligand to recruit CRBN protein and serve as a key intermediate for the synthesis of complete PROTAC molecules.