Novel azido and isothiocyanato analogues of [3-(4-phenylalkylpiperazin-1-yl)propyl]bis(4-fluorophenyl)amines as potential irreversible ligands for the dopamine transporter

J Med Chem. 2004 Dec 2;47(25):6128-36. doi: 10.1021/jm049670w.

Abstract

Potential irreversible ligands were prepared, based on a series of 3-(1-piperazinyl)propyl-N,N-bis(4-fluorophenyl)amines, as molecular probes for the dopamine transporter (DAT). Both azido- and isothiocyanato-substituted phenylalkyl analogues were synthesized and evaluated for displacement of [(3)H]WIN 35 428 in rat caudate putamen tissue. All of the analogues showed moderate binding potencies at the DAT. The azido analogue, 16b, was radioiodinated and used to photolabel human DAT-transfected HEK 293 cell membranes. [(125)I]16b irreversibly labeled an approximately 80 kDa band corresponding to the DAT detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This radioligand provides a novel addition to the growing arsenal of structurally diverse irreversible ligands that are being used to identify binding domains on the DAT. Characterizing points of attachment of these irreversible probes to the DAT protein will ultimately help elucidate the three-dimensional arrangement of the transmembrane domains, identify individual binding sites of the DAT inhibitors, and direct future drug design.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Azides / chemical synthesis*
  • Azides / chemistry
  • Azides / pharmacology
  • Binding, Competitive
  • Cell Line
  • Diphenylamine / analogs & derivatives*
  • Diphenylamine / chemical synthesis*
  • Diphenylamine / chemistry
  • Diphenylamine / pharmacology
  • Dopamine / metabolism*
  • Dopamine Plasma Membrane Transport Proteins
  • Humans
  • In Vitro Techniques
  • Iodine Radioisotopes
  • Isothiocyanates / chemical synthesis*
  • Isothiocyanates / chemistry
  • Isothiocyanates / pharmacology
  • Ligands
  • Male
  • Membrane Glycoproteins / metabolism*
  • Membrane Transport Proteins / metabolism*
  • Nerve Tissue Proteins / metabolism*
  • Photoaffinity Labels / chemical synthesis*
  • Photoaffinity Labels / chemistry
  • Photoaffinity Labels / pharmacology
  • Piperazines / chemical synthesis*
  • Piperazines / chemistry
  • Piperazines / pharmacology
  • Putamen / metabolism
  • Radioligand Assay
  • Rats
  • Rats, Sprague-Dawley
  • Structure-Activity Relationship

Substances

  • 3-(4-(3-iodo-4-azidophenylethyl)-1-piperazinyl)propyl-N,N-bis-(4-fluorophenyl)amine
  • Azides
  • Dopamine Plasma Membrane Transport Proteins
  • Iodine Radioisotopes
  • Isothiocyanates
  • Ligands
  • Membrane Glycoproteins
  • Membrane Transport Proteins
  • Nerve Tissue Proteins
  • Photoaffinity Labels
  • Piperazines
  • SLC6A3 protein, human
  • Slc6a3 protein, rat
  • Diphenylamine
  • Dopamine