title: High yield synthesis of high specific activity R-(-)-[11C]epinephrine for routine PET studies in humans.
abstract: R-(-)-[11C]Epinephrine ([11C]EPI) has been synthesized from R-(-)-norepinephrine by direct methylation with [11C]methyl iodide or [11C]methyl triflate. The total synthesis time including HPLC purification was 35-40 min. The radiochemical yields (EOB) were 5-10% for [11C]methyl iodide and 15-25% for [11C]methyl triflate. Radiochemical purity was > 98%; optical purity determined by radio-chiral HPLC was > 97%. The [11C]methyl triflate technique produces R-(-)-[11C]epinephrine in quantities (80-170 mCi) sufficient for multiple positron emission tomography studies in humans. The two synthetic methods are generally applicable to the production of other N-[11C]methyl phenolamines and N-[11C]methyl catecholamines.
authors.affiliation: Department of Internal Medicine, University of Michigan Medical School, Ann Arbor 48109-0552.
authors.forename: P K
authors.initials: PK
authors.lastname: Chakraborty
authors.forename: D L
authors.initials: DL
authors.lastname: Gildersleeve
authors.forename: D M
authors.initials: DM
authors.lastname: Jewett
authors.forename: S A
authors.initials: SA
authors.lastname: Toorongian
authors.forename: M R
authors.initials: MR
authors.lastname: Kilbourn
authors.forename: M
authors.initials: M
authors.lastname: Schwaiger
authors.forename: D M
authors.initials: DM
authors.lastname: Wieland
mesh_terms: D002250:Carbon Radioisotopes; D002851:Chromatography, High Pressure Liquid; D004837:Epinephrine / Q000138:chemical synthesis* / Q000302:isolation & purification; D006801:Humans; D007553:Isotope Labeling / Q000379:methods*; D009638:Norepinephrine / Q000737:chemistry / Q000302:isolation & purification; D013237:Stereoisomerism; D014055:Tomography, Emission-Computed
chemical_list: D002250:Carbon Radioisotopes; D009638:Norepinephrine; D004837:Epinephrine