(1R,5S)-Thalidomide-3,8-diazabicyclo[3.2.1]octane-Boc is a conjugate of E3 ligase ligand and linker , consisting of Thalidomide and the corresponding Linker. (1R,5S)-Thalidomide-3,8-diazabicyclo[3.2.1]octane-Boc can serve as a Cereblon ligand to recruit CRBN protein and serve as a key intermediate for the synthesis of complete PROTAC molecules.