title: Synthesis of new carbon-11-labeled carboxamide derivatives as potential PET dopamine D3 receptor radioligands.
abstract: Carbon-11-labeled carboxamide derivatives, (E)-4-fluoro-N-(4-(4-(2-[(11)C]methoxyphenyl)piperazin-1-yl)butyl)cinnamoylamide, ([(11)C]3a), (E)-4-chloro-N-(4-(4-(2-[(11)C]methoxyphenyl)piperazin-1-yl)butyl)cinnamoylamide ([(11)C]3b), (E)-4-bromo-N-(4-(4-(2-[(11)C]methoxyphenyl)piperazin-1-yl)butyl)cinnamoylamide, ([(11)C]3c), (E)-4-methoxy-N-(4-(4-(2-[(11)C]methoxyphenyl)piperazin-1-yl)butyl)cinnamoylamide ([(11)C]3d), N-(4-(4-(2-[(11)C]methoxyphenyl)piperazin-1-yl)butyl)naphthyl-2-carboxamide ([(11)C]BP897, [(11)C]3e), and N-(4-(4-(2-[(11)C]methoxyphenyl)piperazin-1-yl)butyl)biphenyl-4-carboxamide ([(11)C]3f), have been synthesized as new potential PET radioligands for imaging of dopamine D(3) receptors. The target tracers were prepared by O-[(11)C]methylation of their corresponding precursors using [(11)C]CH(3)OTf and isolated by a simplified solid-phase extraction (SPE) purification procedure in 50-65% radiochemical yields decay corrected to end of bombardment (EOB), 20 min overall synthesis time, and 111-148GBq/micromol specific activity at end of synthesis (EOS).
authors.affiliation: Department of Radiology, Indiana University School of Medicine, Indianapolis, IN 46202-2111, USA.
authors.forename: Mingzhang
authors.initials: M
authors.lastname: Gao
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.forename: Gary D
authors.initials: GD
authors.lastname: Hutchins
authors.forename: Qi-Huang
authors.initials: QH
authors.lastname: Zheng
mesh_terms: D000620:Aminoimidazole Carboxamide / Q000493:pharmacokinetics*; D000818:Animals; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism*; D002250:Carbon Radioisotopes / Q000493:pharmacokinetics; D006801:Humans; D007553:Isotope Labeling / Q000379:methods; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals / Q000737:chemistry / Q000493:pharmacokinetics; D050637:Receptors, Dopamine D3 / Q000378:metabolism*
chemical_list: D002250:Carbon Radioisotopes; D019275:Radiopharmaceuticals; D050637:Receptors, Dopamine D3; D000620:Aminoimidazole Carboxamide