title: Synthesis of [¹¹C]PBR170, a novel imidazopyridine, for imaging the translocator protein with PET.
abstract: The translocator protein (TSPO) ligand 2-(6,8-dichloro-2-(4-ethoxyphenyl)imidazo[1,2-a]pyridin-3-yl)-N-(2-fluoropyridin-3-yl)-N-methylacetamide (PBR170), is a novel imidazopyridineacetamide with high affinity (2.6 nm) and selectivity for the TSPO. The synthesis of [(11)C]PBR170 was accomplished by N-methylation of the corresponding desmethyl precursor with [(11)C]methyl iodide in the presence of sodium hydroxide in dimethylformamide. [(11)C]PBR170 was produced in 30-45% radiochemical yield (decay-corrected, based on [(11)C]methyl iodide) with a radiochemical purity >98% and a specific activity of 90-190 GBq/μmol after 35 min of synthesis time.
authors.affiliation: Department of PET and Nuclear Medicine, Royal Prince Alfred Hospital, Missenden Road, Camperdown NSW 2050, Australia. Electronic address: thomas@nucmed.rpa.cs.nsw.gov.au.
authors.forename: Thomas
authors.initials: T
authors.lastname: Bourdier
authors.affiliation: Department of PET and Nuclear Medicine, Royal Prince Alfred Hospital, Missenden Road, Camperdown NSW 2050, Australia.
authors.forename: David
authors.initials: D
authors.lastname: Henderson
authors.affiliation: LifeSciences, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC NSW 2232, Australia.
authors.forename: Christopher J R
authors.initials: CJ
authors.lastname: Fookes
authors.affiliation: Department of PET and Nuclear Medicine, Royal Prince Alfred Hospital, Missenden Road, Camperdown NSW 2050, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: Lam
authors.affiliation: Department of PET and Nuclear Medicine, Royal Prince Alfred Hospital, Missenden Road, Camperdown NSW 2050, Australia.
authors.forename: Filomena
authors.initials: F
authors.lastname: Mattner
authors.affiliation: Department of PET and Nuclear Medicine, Royal Prince Alfred Hospital, Missenden Road, Camperdown NSW 2050, Australia; Sydney Medical School, University of Sydney, Camperdown NSW 2050, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Fulham
authors.affiliation: Department of PET and Nuclear Medicine, Royal Prince Alfred Hospital, Missenden Road, Camperdown NSW 2050, Australia.
authors.forename: Andrew
authors.initials: A
authors.lastname: Katsifis
mesh_terms: D000818:Animals; D002250:Carbon Radioisotopes / Q000737:chemistry / Q000493:pharmacokinetics; D007553:Isotope Labeling / Q000379:methods; D057054:Molecular Imaging / Q000379:methods*; D009928:Organ Specificity; D049268:Positron-Emission Tomography / Q000379:methods*; D011485:Protein Binding; D011725:Pyridines / Q000138:chemical synthesis* / Q000493:pharmacokinetics*; D019275:Radiopharmaceuticals / Q000138:chemical synthesis / Q000493:pharmacokinetics; D051381:Rats; D017208:Rats, Wistar; D018079:Receptors, GABA / Q000378:metabolism*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014018:Tissue Distribution
chemical_list: D002250:Carbon Radioisotopes; D011725:Pyridines; D019275:Radiopharmaceuticals; D018079:Receptors, GABA; C499229:TSPO protein, human
keywords: Carbon-11; PET; TSPO; [(11)C]PBR170; [(11)C]methyl iodide