Design, synthesis, and biological activity of N6-substituted-4'-thioadenosines at the human A3 adenosine receptor

Bioorg Med Chem. 2006 Jul 15;14(14):4718-30. doi: 10.1016/j.bmc.2006.03.030. Epub 2006 Apr 5.

Abstract

A large series of N6-substituted-4'-thioadenosines were synthesized starting from D-gulonic-gamma-lactone, and structure-activity relationships were studied at the human A3 and other subtypes of adenosine receptors (ARs). 2-Chloro-substituted and 2-H analogues were compared. 2-Chloro-N6-methyl-4'-thioadenosine 19b was a highly potent and selective agonist (Ki=0.8+/-0.1 nM in binding) at the A3AR, and displayed the same relative efficacy in receptor activation as a known full agonist, Cl-IB-MECA. Most of N6-substituted-4'-thioadenosines were less potent in binding than the corresponding N6-substituted-adenosines or N6-substituted-4'-thioadenosine-5'-uronamides. N6-(3-Iodobenzyl) derivative 19g was demonstrated to be an A3AR-selective partial agonist displaying a Ki value of 3.2 nM.

Publication types

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

MeSH terms

  • Adenosine / analogs & derivatives*
  • Adenosine / chemical synthesis
  • Adenosine / chemistry
  • Adenosine / metabolism
  • Adenosine / pharmacology
  • Adenosine A3 Receptor Agonists*
  • Animals
  • CHO Cells
  • Cricetinae
  • Cyclic AMP / metabolism
  • Drug Design
  • Humans
  • In Vitro Techniques
  • Kinetics
  • Ligands
  • Magnetic Resonance Spectroscopy
  • Receptor, Adenosine A1 / metabolism
  • Receptor, Adenosine A2A / metabolism
  • Recombinant Proteins / agonists
  • Structure-Activity Relationship
  • Thionucleosides / chemical synthesis*
  • Thionucleosides / chemistry
  • Thionucleosides / metabolism
  • Thionucleosides / pharmacology*

Substances

  • Adenosine A3 Receptor Agonists
  • Ligands
  • Receptor, Adenosine A1
  • Receptor, Adenosine A2A
  • Recombinant Proteins
  • Thionucleosides
  • Cyclic AMP
  • Adenosine