Syntheses and biological evaluation of (18)F-labeled 3-(1-benzyl-piperidin-4-yl)-1-(1-methyl-1H-indol-3-yl)propan-1-ones for in vivo mapping of acetylcholinesterase

Nucl Med Biol. 2000 Apr;27(3):263-7. doi: 10.1016/s0969-8051(00)00086-x.

Abstract

We synthesized novel (18)F-labeled acetylcholinesterase (AChE) inhibitors, 3-[1-(3- and 4-[(18)F]fluoromethylbenzyl)piperidin-4-yl]-1-(1-methyl-1H-i ndol-3-yl )propan-1-ones ([(18)F]1 and [(18)F]2) and 3-[1-(4-[(18)F]fluorobenzyl)piperidin-4-yl]-1-(1-methyl-1H-i ndol-3-yl )propan-1-one ([(18)F]3) in high yields (decay-corrected, 25%-40%) and with high effective specific activities (>37 GBq/micromol). Tissue distribution studies of the [(18)F]1 and the [(18)F]3 in mice showed the nonspecific bindings in brain regions, with metabolic defluorination of the [(18)F]1. The result suggests that these radioligands may not be suitable agents for in vivo mapping of AChE, despite their potent in vitro anti-AChE activities.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylcholinesterase / metabolism*
  • Animals
  • Biotransformation
  • Brain / enzymology*
  • Brain / physiology
  • Brain Mapping
  • Cholinesterase Inhibitors / chemical synthesis*
  • Cholinesterase Inhibitors / pharmacology
  • Drug Stability
  • Fluorine Radioisotopes
  • Indoles / chemical synthesis*
  • Indoles / pharmacokinetics
  • Indoles / pharmacology
  • Male
  • Mice
  • Mice, Inbred ICR
  • Piperidines / chemical synthesis*
  • Piperidines / pharmacokinetics
  • Piperidines / pharmacology
  • Radiopharmaceuticals / chemical synthesis*
  • Radiopharmaceuticals / pharmacokinetics
  • Radiopharmaceuticals / pharmacology
  • Tissue Distribution

Substances

  • Cholinesterase Inhibitors
  • Fluorine Radioisotopes
  • Indoles
  • Piperidines
  • Radiopharmaceuticals
  • Acetylcholinesterase