Azido-PEG6-THP is a PEG-based PROTAC linker utilized in the synthesis of PROTAC molecules. It functions as a click chemistry reagent, featuring an azide group that can undergo copper-catalyzed azide-alkyne cycloaddition reactions (CuAAc) with molecules containing alkyne groups. Additionally, it can engage in strain-promoted azide-alkyne cycloaddition reactions (SPAAC) with molecules that have DBCO or BCN groups.