N- (m-PEG4) -N'- (azide-PEG4) -Cy3

N- (m-PEG4) -N'- (azide-PEG4) -Cy3 is a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[1]. N- (m-PEG4) -N'- (azide-PEG4) -Cy3 is a click chemistry reagent, it contains an Azide group and can undergo copper-catalyzed azide-alkyne cycloaddition reaction (CuAAc) with molecules containing Alkyne groups. It can also undergo strain-promoted alkyne-azide cycloaddition (SPAAC) reactions with molecules containing DBCO or BCN groups.