N-(hydroxy-PEG2)-N'-(azide-PEG3)-Cy5 is a PEG linker containing a cyanine dye with excitation/emmission maximum 649/667 nm as well as an azide group, which enables Click Chemistry. The hydophilic PEG spacer increases solubility in aqueous media.
N-PEG3-N'-(azide-PEG3)-Cy5 (chloride) is a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[1]. N-PEG3-N'-(azide-PEG3)-Cy5 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.