Thalidomide-5-propargyl is a propargyl-modified Thalidomide (HY-14658), that acts as a Cereblon ligand to recruit CRBN proteins. Thalidomide-5-propargyl use alkynyl group at the end to be directly used in the synthesis of triazoles in the synthesis of PROTAC molecules, and is a key intermediate in the synthesis of PROTAC molecules based on CRBN design[1].