title: Synthesis of [11C]FEDAA1106 as a new PET imaging probe of peripheral benzodiazepine receptor expression.
abstract: Peripheral benzodiazepine receptor (PBR) is associated with neuroinflammation and tumor progression. [(11)C]DAA1106 and [(18)F]FEDAA1106 are two promising radioligands for positron emission tomography (PET) imaging of PBR. This study was designed to develop a new radiolabeled analog of [(11)C]DAA1106 and [(18)F]FEDAA1106, [(11)C]FEDAA1106, for PET imaging of PBR expression in brain and cancer. Precursor N-(5-fluoro-2-phenoxyphenyl)-N-(2-(2-fluoroethoxy)-5-hydroxybenzyl)acetamide (9) was synthesized in multiple steps with moderate to high chemical yields. Precursor 9 was labeled by [(11)C]CH(3)OTf and isolated by high pressure liquid chromatography (HPLC) purification to provide target radioligand N-(5-fluoro-2-phenoxyphenyl)-N-(2-(2-fluoroethoxy)-5-[(11)C]methoxybenzyl)acetamide ([(11)C]FEDAA1106, [(11)C]10) in 60-70% radiochemical yields, decay corrected to end of bombardment (EOB), based on [(11)C]CO(2). The specific activity of the target radiotracer [(11)C]10 was in a range of 111-185GBq/micromol at the end of synthesis (EOS).
authors.affiliation: Department of Radiology, Indiana University School of Medicine, 1345 West 16th Street, L3-208, Indianapolis, IN 46202-2111, USA.
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.forename: Mingzhang
authors.initials: M
authors.lastname: Gao
authors.forename: Gary D
authors.initials: GD
authors.lastname: Hutchins
authors.forename: Qi-Huang
authors.initials: QH
authors.lastname: Zheng
mesh_terms: D000081:Acetamides / Q000138:chemical synthesis* / Q000737:chemistry; D000544:Alzheimer Disease / Q000175:diagnosis / Q000378:metabolism; D000818:Animals; D001921:Brain / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D008822:Mice, Transgenic; D015394:Molecular Structure; D009455:Neurofibroma / Q000175:diagnosis*; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals / Q000138:chemical synthesis* / Q000737:chemistry; D011963:Receptors, GABA-A / Q000096:biosynthesis*; D013237:Stereoisomerism
chemical_list: D000081:Acetamides; C475621:N-(5-fluoro-2-phenoxyphenyl)-N-(2-fluoroethyl-5-methoxybenzyl)acetamide; D019275:Radiopharmaceuticals; D011963:Receptors, GABA-A