Used as a key building block in the synthesis of chelating agents, particularly in the development of MRI contrast agents. Its structure allows for strong and stable binding with metal ions like gadolinium, enhancing the contrast in magnetic resonance imaging. Also employed in radiopharmaceuticals for diagnostic imaging and targeted therapy, where it helps deliver radioactive metal ions selectively to diseased tissues. Additionally, cyclen derivatives are explored in sensing applications and catalysis due to their selective ion coordination properties.