title: Syntheses of F-18 labeled fluoroalkyltyrosine derivatives and their biological evaluation in rat bearing 9L tumor.
abstract: We hereby report the synthesis of four fluorine-18 labeled tyrosine derivatives, 3-(2-[(18)F]fluoroethyl)tyrosine ([(18)F]1, [(18)F]ortho-FET), 3-(3-[(18)F]fluoropropyl)tyrosine ([(18)F]2, [(18)F]ortho-FPT) O-methyl-[3-(2-[(18)F]fluoroethyl)]tyrosine ([(18)F]3, [(18)F]MFET), and O-methyl-[3-(3-[(18)F]fluoropropyl)]tyrosine ([(18)F]4, [(18)F]MFPT). The fluorine-18 labeled tyrosine derivatives were prepared by the displacement reaction of the ethyl and propyl tosylates with K[(18)F]/K2.2.2 in acetonitrile under no-carrier-added (NCA) conditions, followed by hydrolysis with 4N HCl. The biological properties of labeled compounds were evaluated in rats bearing 9L tumor after an intravenous injection and PET image was obtained. The tumor/blood and tumor/brain ratios were 2.06, 2.92 for [(18)F]1, 2.25, 4.05 for [(18)F]2, 2.88, 1.90 for [(18)F]3, and 2.00, 2.60 for [(18)F]4 at 60 min post injection, respectively. The PET image showed localized accumulation of PET tracers in 9L glioma of the rat.
authors.affiliation: Laboratory of Radiopharmaceuticals, Korea Institute of Radiological and Medical Sciences, 215-4 Gongneungdong, Nowongu, Seoul 139-706, Republic of Korea.
authors.forename: Byung Seok
authors.initials: BS
authors.lastname: Moon
authors.forename: Tae Sup
authors.initials: TS
authors.lastname: Lee
authors.forename: Kyo Chul
authors.initials: KC
authors.lastname: Lee
authors.forename: Gwang Il
authors.initials: GI
authors.lastname: An
authors.forename: Gi Jeong
authors.initials: GJ
authors.lastname: Cheon
authors.forename: Sang Moo
authors.initials: SM
authors.lastname: Lim
authors.forename: Chang Woon
authors.initials: CW
authors.lastname: Choi
authors.forename: Dae Yoon
authors.initials: DY
authors.lastname: Chi
authors.forename: Kwon Soo
authors.initials: KS
authors.lastname: Chun
mesh_terms: D000818:Animals; D001932:Brain Neoplasms / Q000378:metabolism; D005462:Fluorine Radioisotopes / Q000737:chemistry*; D005910:Glioma / Q000378:metabolism; D019275:Radiopharmaceuticals / Q000138:chemical synthesis / Q000737:chemistry* / Q000493:pharmacokinetics*; D051381:Rats; D011916:Rats, Inbred F344; D016610:Tissue Embedding; D014443:Tyrosine / Q000031:analogs & derivatives*
chemical_list: D005462:Fluorine Radioisotopes; D019275:Radiopharmaceuticals; D014443:Tyrosine