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Synthesis and biological evaluation of fluorescent GAT-ligands based on asymmetric substituted BODIPY dyes


The present study aimed at the development of fluorescent inhibitors addressing the GABA transporters mGAT1–mGAT4 as potential tool compounds in fluorescence based biological assays. The design of these fluorescent GAT inhibitors followed the structural motifs common for many GAT1–GAT4 inhibitors publicly known except that the lipophilic domain present in this compounds was replaced by a BODIPY moiety to serve as a fluorescent subunit. The fluorescent compounds obtained that way were tested for their inhibitory potencies and subtype selectivities at the four murine GABA transporter subtypes mGAT1–mGAT4 and for their binding affinity for mGAT1. All BODIPY derivatives displayed only low inhibitory potencies and subtype selectivities at the GABA transport proteins mGAT1–mGAT4, as well as low affinities for mGAT1. Still, compounds were found with reasonable binding affinities towards mGAT1 (pKi ~ 5.0) and inhibitory potencies at mGAT2 and mGAT4 (pIC50 ~ 5.0).

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Correspondence to Klaus T. Wanner.

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Daerr, M., Allmendinger, L., Höfner, G. et al. Synthesis and biological evaluation of fluorescent GAT-ligands based on asymmetric substituted BODIPY dyes. Med Chem Res (2020). https://doi.org/10.1007/s00044-020-02521-8

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  • Fluorescent ligand
  • GABA transporters
  • GAT
  • GABA uptake
  • Biological activity