11-Azidoundecanoic acid, a click chemistry reagent with an azide group, serves as a hydrophobic bioconjugation linker amenable to further modification via Staudinger ligation or Click chemistry. This compound is recognized as a substrate by lipoic acid ligase (LpIA) for labeling purposes [1] [2]. Additionally, 11-Azidoundecanoic acid can participate in copper-catalyzed azide-alkyne cycloaddition (CuAAc) with alkyne-bearing molecules and engage in strain-promoted alkyne-azide cycloaddition (SPAAC) with molecules featuring DBCO or BCN groups.