Quinuclidine and DABCO Enhance the Radiofluorinations of 5-Substituted 2-Halopyridines

European Journal of Organic Chemistry
Gregory R NaumiecVictor W Pike

Abstract

Positron emission tomography (PET) is an important molecular imaging technique for medical diagnosis, biomedical research and drug development. PET tracers for molecular imaging contain β+-emitting radionuclides, such as carbon-11 (t1/2 = 20.4 min) or fluorine-18 (t1/2 = 109.8 min). The [18F]2-fluoro-pyridyl moiety features in a few prominent PET radiotracers, not least because this moiety is usually resistant to unwanted radiodefluorination in vivo. Various methods have been developed for labeling these radiotracers from cyclotron-produced no-carrier-added [18F]fluoride ion, mainly based on substitution of a leaving group, such as halide (Cl or Br), or preferably a better leaving group, such as nitro or trimethylammonium. However, precursors with a good leaving group are sometimes more challenging or lengthy to prepare. Methods for enhancing the reactivity of more readily accessible 2-halopyridyl precursors are therefore desirable, especially for early radiotracer screening programs that may require the quick labeling of several homologous radiotracer candidates. In this work, we explored a wide range of additives for beneficial effect on nucleophilic substitution by [18F]fluoride ion in 5-subsituted 2-halopyridines (halo = Cl...Continue Reading

References

Aug 2, 2000·Proceedings of the National Academy of Sciences of the United States of America·M E Phelps
Mar 17, 2004·Molecular Imaging and Biology : MIB : the Official Publication of the Academy of Molecular Imaging·Julie A McCarronLars Farde
Oct 28, 2005·Current Pharmaceutical Design·F Dollé
Jan 21, 2006·Angewandte Chemie·Noriaki KudoGregory C Fu
Mar 21, 2006·Angewandte Chemie·Haoran Sun, Stephen G DiMagno
Jul 14, 2007·Angewandte Chemie·Mahiuddin BaidyaHerbert Mayr
Jul 21, 2009·Trends in Pharmacological Sciences·Victor W Pike
Jul 12, 2011·Bioorganic & Medicinal Chemistry Letters·Annelaure DamontFrédéric Dollé
Aug 16, 2011·British Journal of Clinical Pharmacology·Paul M MatthewsRoger N Gunn
Feb 11, 2012·Journal of Nuclear Medicine : Official Publication, Society of Nuclear Medicine·Zsolt CselényiLars Farde
Dec 14, 2012·Journal of Alzheimer's Disease : JAD·David T ChienHartmuth C Kolb
Feb 8, 2013·Chemical Communications : Chem Comm·Joong-Hyun ChunVictor W Pike
Jun 25, 2013·Applied Radiation and Isotopes : Including Data, Instrumentation and Methods for Use in Agriculture, Industry and Medicine·Marianne PattOsama Sabri
Nov 29, 2013·Journal of Labelled Compounds & Radiopharmaceuticals·Brian G HockleyPeter J H Scott
Jun 12, 2014·Journal of the American Chemical Society·Patrick S Fier, John F Hartwig
Aug 22, 2014·Journal of Medicinal Chemistry·Markus PielFrank Rösch
Dec 25, 2015·European Journal of Clinical Microbiology & Infectious Diseases : Official Publication of the European Society of Clinical Microbiology·L HuangC Duan
Nov 16, 2016·Chemical Communications : Chem Comm·Antonio Bermejo GómezMagnus Schou

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