A new facile synthetic route to [C-11]GSK189254, a selective PET radioligand for imaging of CNS histamine H-3 receptor

Department of Radiology and Imaging Sciences, Indiana University School of Medicine, 1345 West 16th Street, Room 202, Indianapolis, IN 46202, USA.
Bioorganic & medicinal chemistry letters (Impact Factor: 2.33). 05/2012; 22(14):4713-8. DOI: 10.1016/j.bmcl.2012.05.076
Source: PubMed

ABSTRACT GSK189254 and its corresponding precursor GSK185071B were synthesized from 3-methoxyphenylacetic acid with 6-chloropyridine-3-carbolic acid or 6-chloronicotinamide in 8 and 7 steps with either 6% or 7% and either 14% or 16% yield, respectively. [(11)C]GSK189254 was prepared from GSK185071B with [(11)C]CH(3)OTf through N-[(11)C]methylation and isolated by HPLC combined with solid-phase extraction (SPE) in 50-60% radiochemical yield based on [(11)C]CO(2) and decay corrected to end of bombardment (EOB), with 370-740 GBq/μmol specific activity at EOB.


Available from: Qi-Huang Zheng, Sep 10, 2014
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