N-(azide-PEG3)-N'-(PEG4-acid)-Cy5 is a PEG linker containing a cyanine dye with excitation/emmission maximum 649/667 nm and a free terminal carboxyl acid. Terminal carboxylic acid can react with primary amine groups in the presence of of activators (e.g. EDC, or HATU) to form a stable amide bond. The hydophilic PEG spacer increases solubility in aqueous media.
N-(Azide-PEG3)-N'-(PEG4-acid)-Cy5 is a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[1]. N-(Azide-PEG3)-N'-(PEG4-acid)-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.
