title: Radiosynthesis of a ⁶⁸Ga labeled matrix metalloproteinase inhibitor as a potential probe for PET imaging.
abstract: A matrix metalloproteinase inhibitor based on a barbiturate scaffold was conjugated with a cyclooctyne derivative of the (radio)metal chelator DOTA via strain induced azide alkyne cycloaddition. Subsequent radiolabeling with (68)Ga yielded the corresponding radiometal labeled target compound (68)Ga-4 with a yield of 87% (decay corrected). The target molecule was also synthesized by a second synthesis route, the reaction of a pre-labeled (68)Ga-cyclooctyne-DOTA derivative (68)Ga-1 with an azide bearing barbiturate 3. This approach offers a valuable alternative for providing the desired (68)Ga-radiolabeled target compound. But, in this case, the strain induced cycloaddition of the reported pre-labeled cyclooctyne-DOTA derivative (68)Ga-1 with azides was proven to be slow at room temperature and heating was necessary for acceptable reaction times.
authors: University Hospital Münster, Department of Nuclear Medicine, Albert-Schweitzer-Campus 1, Building A1, 48149 Münster, Germany. claesene@uni-muenster.de
authors: Michael
authors: M
authors: Claesener
authors: Otmar
authors: O
authors: Schober
authors: Stefan
authors: S
authors: Wagner
authors: Klaus
authors: K
authors: Kopka
mesh_terms: D002851:Chromatography, High Pressure Liquid; D005710:Gallium Radioisotopes; D009682:Magnetic Resonance Spectroscopy; D061965:Matrix Metalloproteinase Inhibitors; D049268:Positron-Emission Tomography; D011480:Protease Inhibitors / Q000138:chemical synthesis*; D011854:Radiochemistry; D019275:Radiopharmaceuticals / Q000138:chemical synthesis*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D005710:Gallium Radioisotopes; D061965:Matrix Metalloproteinase Inhibitors; D011480:Protease Inhibitors; D019275:Radiopharmaceuticals