N-[18F]fluoroethylpiperidin-4-ylmethyl butyrate: a novel radiotracer for quantifying brain butyrylcholinesterase activity by positron emission tomography

Bioorg Med Chem Lett. 2004 Apr 19;14(8):1927-30. doi: 10.1016/j.bmcl.2004.01.080.


In Alzheimer's disease, cerebral cortical butyrylcholinesterase (BChE) activity is reported to be elevated. Our aim was to develop a novel (18)F-labeled tracer for quantifying cerebral BChE activity by positron emission tomography. With in vitro screening of N-[(14)C]ethylpiperidin-3- and 4-ylmethyl esters, N-[(14)C]ethylpiperidin-4-ylmethyl butyrate was selected as a lead for (18)F-labeling, affording N-[(18)F]fluoroethylpiperidin-4-ylmethyl butyrate. The (18)F-labeled butyrate showed the required properties for in vivo BChE measurement, that is, the lipophilic nature of the authentic ester, high specificity to BChE, a moderate hydrolysis rate, and the hydrophilic nature of the metabolite.

MeSH terms

  • Acetylcholinesterase / analysis
  • Acetylcholinesterase / metabolism
  • Brain / diagnostic imaging
  • Brain / enzymology*
  • Butyrates* / chemical synthesis
  • Butyrates* / chemistry
  • Butyrylcholinesterase / analysis*
  • Butyrylcholinesterase / metabolism*
  • Fluorine Radioisotopes*
  • Humans
  • Hydrolysis
  • Piperidines* / chemical synthesis
  • Piperidines* / chemistry
  • Radiopharmaceuticals* / chemical synthesis
  • Radiopharmaceuticals* / chemistry
  • Substrate Specificity
  • Tomography, Emission-Computed / methods*


  • Butyrates
  • Fluorine Radioisotopes
  • N-fluoroethylpiperidin-4-ylmethylbutyrate
  • Piperidines
  • Radiopharmaceuticals
  • Acetylcholinesterase
  • Butyrylcholinesterase