New synthesis and tritium labeling of a selective ligand for studying high-affinity γ-hydroxybutyrate (GHB) binding sites

J Med Chem. 2013 Oct 24;56(20):8201-5. doi: 10.1021/jm4011719. Epub 2013 Oct 4.

Abstract

3-Hydroxycyclopent-1-enecarboxylic acid (HOCPCA, 1) is a potent ligand for the high-affinity GHB binding sites in the CNS. An improved synthesis of 1 together with a very efficient synthesis of [(3)H]-1 is described. The radiosynthesis employs in situ generated lithium trimethoxyborotritide. Screening of 1 against different CNS targets establishes a high selectivity, and we demonstrate in vivo brain penetration. In vitro characterization of [(3)H]-1 binding shows high specificity to the high-affinity GHB binding sites.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Benzocycloheptenes / chemistry
  • Benzocycloheptenes / metabolism
  • Binding Sites
  • Binding, Competitive
  • Brain / metabolism
  • Carboxylic Acids / chemical synthesis
  • Carboxylic Acids / chemistry
  • Carboxylic Acids / metabolism*
  • Cell Line
  • Central Nervous System / metabolism*
  • Cyclopentanes / chemical synthesis
  • Cyclopentanes / chemistry
  • Cyclopentanes / metabolism*
  • Drug Stability
  • Hydroxybutyrates / chemistry
  • Hydroxybutyrates / metabolism*
  • Kinetics
  • Ligands
  • Male
  • Models, Chemical
  • Molecular Structure
  • Radioligand Assay
  • Rats
  • Rats, Sprague-Dawley
  • Synaptic Membranes / metabolism
  • Tritium / metabolism
  • gamma-Aminobutyric Acid / chemistry
  • gamma-Aminobutyric Acid / metabolism

Substances

  • 3-hydroxycyclopent-1-enecarboxylic acid
  • Benzocycloheptenes
  • Carboxylic Acids
  • Cyclopentanes
  • Hydroxybutyrates
  • Ligands
  • Tritium
  • NCS 382
  • 4-hydroxybutyric acid
  • gamma-Aminobutyric Acid