6-Azidohexanoic Acid NHS Ester

An azido-containing building block that can be used to derivatize primary amines with an azido group via a stable amide bond. The NHS ester reacts with primary amines at pH 7-9 forming a stable amide bond. The azide (N3) group reacts with terminal alkynes via CuAAC, strained cyclooctynes (e.g. DBCO or BCN compounds) via Cu-free click reaction or with phosphine-labeled molecules by a mechanism known as Staudinger chemistry, enabling efficient and specific conjugation of derivatized molecules in biological samples.