title: Syntheses of the first endothelin-A- and -B-selective radioligands for positron emission tomography.
abstract: We have synthesized two potential positron emission tomography (PET) radioligands for the endothelin (ET) receptor. [11C]-PD156707 was produced by O-methylation of PD169390 using [11C]iodomethane. Radiochemical conversions of the order of 74 +/- 3.2% (n = 8) were obtained. The radiochemical purity of the isolated [11C]-PD156707 was 99% and the specific activity was 538 mCi/micromol. [18F]-BQ3020 was produced from [18F]fluoride in a total radiochemical yield of 2.7 +/- 0.4% (n = 10) in 238 +/- 5 min. The radiochemical purity was 95% and specific activities of the order of 670-930 mCi/micromol were obtained.
authors.affiliation: Clinical Pharmacology Unit, University of Cambridge, Addenbrooke's Hospital, UK. pjj20@medschl.cam.ac.uk
authors.forename: P
authors.initials: P
authors.lastname: Johnström
authors.forename: F I
authors.initials: FI
authors.lastname: Aigbirhio
authors.forename: J C
authors.initials: JC
authors.lastname: Clark
authors.forename: S P
authors.initials: SP
authors.lastname: Downey
authors.forename: J D
authors.initials: JD
authors.lastname: Pickard
authors.forename: A P
authors.initials: AP
authors.lastname: Davenport
mesh_terms: D000595:Amino Acid Sequence; D002250:Carbon Radioisotopes; D004149:Dioxoles / Q000138:chemical synthesis*; D016232:Endothelins / Q000138:chemical synthesis*; D005462:Fluorine Radioisotopes; D006801:Humans; D008024:Ligands; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000138:chemical synthesis*; D044022:Receptor, Endothelin A; D044023:Receptor, Endothelin B; D017466:Receptors, Endothelin / Q000032:analysis*; D014055:Tomography, Emission-Computed
chemical_list: D002250:Carbon Radioisotopes; D004149:Dioxoles; D016232:Endothelins; D005462:Fluorine Radioisotopes; D008024:Ligands; C093321:PD 156707; D010446:Peptide Fragments; D044022:Receptor, Endothelin A; D044023:Receptor, Endothelin B; D017466:Receptors, Endothelin; C075771:BQ 3020