Used primarily as a bifunctional chelating agent in radiopharmaceuticals, this compound enables stable conjugation of radioactive metal ions to targeting biomolecules such as antibodies or peptides. Its isothiocyanate group reacts selectively with amine groups on proteins, forming stable thiourea linkages, while the macrocyclic structure strongly binds diagnostic or therapeutic radionuclides like gallium-68, copper-64, or yttrium-90. This makes it valuable in nuclear medicine for PET imaging and targeted radiotherapy, especially in cancer diagnostics and treatment. The compound’s design supports high in vivo stability and efficient labeling under mild conditions, improving pharmacokinetics and reducing off-target accumulation of radioactivity.