% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@INPROCEEDINGS{Ermert:910174,
      author       = {Ermert, Johannes and Willmann, Michael and Neumaier, Bernd},
      title        = {{R}adiosynthesis and biological evaluation of
                      [18{F}]{R}91150, a selective 5-{HT}2{A} receptor
                      antagonistfor {PET} imaging},
      reportid     = {FZJ-2022-03654},
      year         = {2022},
      abstract     = {Serotonergic 5-HT2A receptors (5-HT2ARs) in cortical and
                      forebrain regions are an important substrate for
                      theneuromodulatory actions of serotonin in the brain. They
                      have been implicated in the etiology of manyneuropsychiatric
                      disorders and serve as a target for (novel) antipsychotic,
                      antidepressant and anxiolytic drugs.Positron emission
                      tomography (PET) imaging using suitable radioligands can be
                      applied for in vivo quantificationof (alterations in)
                      receptor densities and receptor occupancy for therapy
                      evaluation [1]. The original radiosynthesisof the selective
                      5-HT2AR antagonist [18F]R91150 was performed in six steps,
                      which is laborious, time-consuming,and has low RCYs of
                      $<5\%,$ preventing widespread use of this radioligand [2].
                      In this work, [18F]R91150 wasprepared using late-stage
                      Cu-mediated radiofluorination of a corresponding
                      NBoc-protected boronic acid pinacoleester to simplify and
                      accelerate synthesis of the radioligand. Boc-protected
                      [18F]R91150 was prepared in a yield $of10-15\%$
                      (non-decay-corrected (n.d.c.), determined by radio-HPLC,
                      n=3) within 10 min and isolated by SPE (C18cartridge).
                      Deprotection by TFA at 80 °C for 5 min succeeded
                      quantitatively. Isolation by analytical radio-HPLCafforded
                      the desired 5-HT2A-radioligand [18F]R91150 in a yield of
                      $10\%$ (n.d.c.) after 60 min. Autoradiographicexamination of
                      [18F]R91150 revealed discrete accumulation in specific brain
                      areas, that was entirely replaceable bynon-radioactive
                      R91150, altanserin and (+)-lisuride. As expected, the less
                      5-HT2A specific (-)-lisuride could notcompletely compete
                      with the binding of [18F]R91150. The in-vitro evaluation of
                      [18F]R91150 revealed the potentialof this tracer for PET
                      imaging of 5-HT2AR status in the human brain [3]. Future
                      studies will focus on the in vivobehaviour of [18F]R91150
                      and the transfer of its synthesis to an automated module for
                      clinical applications.},
      month         = {Sep},
      date          = {2022-09-14},
      organization  = {DPhG Annual Meeting 2022, Marburg
                       (Germany), 14 Sep 2022 - 16 Sep 2022},
      subtyp        = {Invited},
      cin          = {INM-5},
      cid          = {I:(DE-Juel1)INM-5-20090406},
      pnm          = {5253 - Neuroimaging (POF4-525)},
      pid          = {G:(DE-HGF)POF4-5253},
      typ          = {PUB:(DE-HGF)6},
      url          = {https://juser.fz-juelich.de/record/910174},
}