Enantiomerically pure hexahydropyrazinoquinolines as potent and selective dopamine 3 subtype receptor ligands

J Med Chem. 2005 May 5;48(9):3171-81. doi: 10.1021/jm049031l.


We report the design and synthesis of a series of enantiomerically pure hexahydropyrazinoquinolines as potent and selective ligands for the dopamine 3 subtype receptor using a newly developed synthetic method and using in vitro pharmacological evaluation. Our efforts yielded optically pure ligands with high affinities for the D(3) receptor and outstanding selectivity over closely related D(1)-like and D(2)-like receptors. For example, compound 38a has a K(i) value of 5.7 nM to the D(3) receptor and selectivity greater than 10000- and 1600-fold over the D(1)-like and D(2)-like receptors, respectively, and thus is one of the most selective D(3) ligands reported to date.

MeSH terms

  • Animals
  • Binding Sites
  • Brain / metabolism
  • Crystallography, X-Ray
  • In Vitro Techniques
  • Ligands
  • Male
  • Models, Molecular
  • Molecular Structure
  • Pyrazines / chemical synthesis*
  • Pyrazines / chemistry
  • Pyrazines / pharmacology
  • Quinolines / chemical synthesis*
  • Quinolines / chemistry
  • Quinolines / pharmacology
  • Radioligand Assay
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Dopamine D2 / metabolism*
  • Receptors, Dopamine D3
  • Stereoisomerism
  • Structure-Activity Relationship


  • Drd3 protein, rat
  • Ligands
  • Pyrazines
  • Quinolines
  • Receptors, Dopamine D2
  • Receptors, Dopamine D3