BCN-exo-PEG2-maleimide, an ADC Linker featuring two PEG units, incorporates the lyophilic bidentate macrocyclic ligand BCN for the synthesis of macrocyclic complexes. In the realm of click chemistry, this compound reacts with azide-containing molecules to form stable triazoles without the need for catalysts. The maleimide group (-Maleimide) of BCN-exo-PEG2-maleimide is prone to degradation in aqueous environments and has applications in drug delivery research.