167569-09-7Relevant articles and documents
Trifluoromethanesulfonic acid, an alternative solvent medium for the direct electrophilic fluorination of DOPA: New syntheses of 6-[18F]fluoro- L-DOPA and 6-[18F]fluoro-D-DOPA
Azad, Babak Behnam,Chirakal, Raman,Schrobilgen, Gary J.
, p. 1236 - 1242 (2007)
Previous work from this laboratory has shown that the direct fluorination of 3, 4-dihydroxy-phenyl-L-alanine (L-DOPA) in anhydrous HF (aHF) or BF 3/HF with F2 is an efficient method for the synthesis of 6-fluoro-L-DOPA. Since then, 18F-labeled 6-fluoro-L-DOPA ([ 18F]6-fluoro-L-DOPA) has been used to study presynaptic dopaminergic function in the human brain and to monitor gastrointestinal carcinoid tumors. This work demonstrates that the reactivity and selectivity of F2 toward L-DOPA in CF3SO3H is comparable with that in aHF. This new synthetic procedure has led to the production of [18F] fluoro-L-DOPA and [18F]fluoro-L-DOPA isomers in 17 ± 2% radiochemical yields (decay corrected with respect to [18F]F 2). The 2- and 6-FDOPA isomers were separated by HPLC and subsequently characterized by 19F NMR spectroscopy. The corresponding [18F]-FDOPA enantiomers have been obtained in clinically useful quantities by a synthetic approach that avoids the use of aHF. Copyright
Synthesis of 6-[11C]methyl-m-tyrosine ([11C]6MemTyr) for dopamine synthesis imaging in living brain using PET
Kanazawa, Masakatsu,Ohba, Hiroyuki,Iwazaki, Aiko,Kakiuchi, Takeharu,Tsukada, Hideo
, p. 729 - 734 (2015)
A novel PET probe, 6-[11C]methyl-m-tyrosine ([11C]6MemTyr), was developed for quantitative imaging of presynaptic dopamine (DA) synthesis in the living brain using positron emission tomography (PET). This probe was evaluated by comparison with conventional 6-[18F]fluoro-l-dopa ([18F]FDOPA). [11C]6MemTyr was labeled using rapid Pd(0)-mediated C-[11C]methylation with [11C]methyl iodide. The synthesis time was only 35 min, and its radiochemical yield was 76%, with radiochemical purity of >99%. PET measurements indicated that [11C]6MemTyr could image presynaptic DA synthesis in the striatum of living monkey brain, providing much higher contrast between the striatum and the cerebellum than that with [18F]FDOPA.
Use of SF6 for the production of electrophilic 18F-fluorination reagents
Krzyczmonik, Anna,Keller, Thomas,Kirjavainen, Anna K.,Lahdenpohja, Salla,Forsback, Sarita,Solin, Olof
, p. 90 - 97 (2017)
Electrophilic 18F-fluorination is an important method for production of tracers for positron emission tomography. The most commonly employed 18F-fluorination reagents [18F]F2, [18F]Selectfluor bis(tri
L-dopa precursor compound, preparation method thereof, and preparation method of 18F labeled L-dopa using the same
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Paragraph 0044; 0142-0146, (2019/10/08)
The present invention relates to an L-dopa precursor compound, a preparation method thereof, and a preparation method of an ^18F labeled L-dopa using the same. The preparation method of the ^18F labeled L-dopa comprises a step of preparing a compound repr
Base/Cryptand/Metal-Free Automated Nucleophilic Radiofluorination of [18F]FDOPA from Iodonium Salts: Importance of Hydrogen Carbonate Counterion
Maisonial-Besset, Aurélie,Serre, Audrey,Ouadi, Ali,Schmitt, Sébastien,Canitrot, Damien,Léal, Fernand,Miot-Noirault, Elisabeth,Brasse, David,Marchand, Patrice,Chezal, Jean-Michel
, p. 7058 - 7065 (2019/01/04)
As evidenced by the number of publications and patents published in the last years, the radiosynthesis of 6-[18F]fluoro-3,4-dihydroxy-L-phenylalanine ([18F]FDOPA) using the nucleophilic [18F]F- process remains currently a challenge for the radiochemists scientific community even if promising methods for the radiofluorination of electron-rich aromatic structures were recently developed from arylboronate, arylstannane or iodonium salt precursors. In such context, based on the use of an iodonium triflate salt precursor, we optimized a fast and efficient radiofluorination route fully automated and free from any base, cryptand or metal catalyst for the radiosynthesis of [18F]FDOPA. Using this method, this clinically relevant radiotracer was produced in 64 min, 27–38 % RCY d.c. (n = 5), >99 % RCP, >99 % ee., and high Am 170–230 GBq/μmol. In addition, this optimization study clearly highlighted the important role of a triflate-hydrogen carbonate counterion exchange during the radiolabeling process to achieve high fluorine-18 incorporation yields.
