title: Novel one-pot one-step synthesis of 2'-[(18)F]fluoroflumazenil (FFMZ) for benzodiazepine receptor imaging.
abstract: We describe the synthesis of 2'-[(18)F]fluoroflumazenil (FFMZ), which differs from the typically used [(18)F]fluoroethylflumazenil (FEFMZ) for benzodiazepine receptor imaging. For one-pot one-step labeling, the precursors, 2'-tosyloxyflumazenil (TFMZ) and 2'-mesyloxyflumazenil (MFMZ), were synthesized in three steps. The precursors were successfully labeled with no-carrier-added (18)F-fluoride which was activated by repeated azeotropic distillation with Kryptofix 2.2.2./potassium carbonate in MeCN. An automated system for labeling and purification of [(18)F]FFMZ was developed. Labeling efficiency and radiochemical purity of [(18)F]FFMZ after synthesis by the automated system were 68% and 98%, respectively. Specific binding of [(18)F]FFMZ to central benzodiazepine receptor of rats was demonstrated by phosphoimaging.
authors.affiliation: Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Young Hyun
authors.initials: YH
authors.lastname: Yoon
authors.forename: Jae Min
authors.initials: JM
authors.lastname: Jeong
authors.forename: Hyung Woo
authors.initials: HW
authors.lastname: Kim
authors.forename: Sung Hyun
authors.initials: SH
authors.lastname: Hong
authors.forename: Yun-Sang
authors.initials: YS
authors.lastname: Lee
authors.forename: Hee Sup
authors.initials: HS
authors.lastname: Kil
authors.forename: Dae Yoon
authors.initials: DY
authors.lastname: Chi
authors.forename: Dong Soo
authors.initials: DS
authors.lastname: Lee
authors.forename: June-Key
authors.initials: JK
authors.lastname: Chung
authors.forename: Myung Chul
authors.initials: MC
authors.lastname: Lee
mesh_terms: D000818:Animals; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism*; D004355:Drug Stability; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005442:Flumazenil / Q000031:analogs & derivatives / Q000138:chemical synthesis* / Q000493:pharmacokinetics*; D007553:Isotope Labeling / Q000295:instrumentation* / Q000379:methods*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000138:chemical synthesis / Q000493:pharmacokinetics; D051381:Rats; D011963:Receptors, GABA-A / Q000378:metabolism*
chemical_list: C483765:2'-fluoroflumazenil; D019275:Radiopharmaceuticals; D011963:Receptors, GABA-A; D005442:Flumazenil