Azido-PEG12-THP is a PROTAC linker belonging to the PEG class, utilized in synthesizing PROTAC molecules. It serves as a click chemistry reagent featuring an azide group. This compound can undergo copper-catalyzed azide-alkyne cycloaddition reactions (CuAAC) with molecules containing alkyne groups. Additionally, it can participate in strain-promoted azide-alkyne cycloaddition (SPAAC) with compounds that have DBCO or BCN groups.