Oxadiazolylindazole sodium channel modulators are neuroprotective toward hippocampal neurones

J Med Chem. 2009 May 14;52(9):2694-707. doi: 10.1021/jm801180p.

Abstract

We report the discovery of a new class of neuroprotective voltage-dependent sodium channel modulators exemplified by (5-(1-benzyl-1H-indazol-3-yl)-1,2,4-oxadiazol-3-yl)methanamine 11 (CFM1178). The compounds were inhibitors of [(14)C]guanidinium ion flux in rat forebrain synaptosomes and displaced binding of the sodium channel ligand [(3)H]BW202W92. 11 and the corresponding N(2)-benzyl isomer, 38 (CFM6058), demonstrated neuroprotective activity in hippocampal slices comparable to sipatrigine. CYP450 enzyme inhibition observed with 11 was reduced with 38. In electrophysiological experiments on dissociated hippocampal neurons, these two compounds caused use- and voltage-dependent block of sodium currents. Sodium channel isoform profiling against Na(v)1.1-1.8 demonstrated that the standard sodium channel blocker lamotrigine had modest activity against Na(v)1.1, while sipatrigine was generally more potent and less selective. 11 and 38 showed potent activity against Na(v)1.6, pointing to pharmacological block of this isoform being consistent with the neuroprotective effect. 38 also showed use dependent block of Na(v)1.6 in HEK cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cytochrome P-450 Enzyme Inhibitors
  • Cytochrome P-450 Enzyme System / metabolism
  • Drug Design
  • Electrophysiological Phenomena
  • Hippocampus / cytology*
  • Hippocampus / drug effects
  • Indazoles / chemistry
  • Indazoles / pharmacology*
  • Male
  • Neurons / drug effects*
  • Neurons / metabolism
  • Neuroprotective Agents / chemistry
  • Neuroprotective Agents / pharmacology*
  • Protein Isoforms / antagonists & inhibitors
  • Protein Isoforms / metabolism
  • Quantitative Structure-Activity Relationship
  • Rats
  • Rats, Wistar
  • Sodium Channel Blockers / chemistry
  • Sodium Channel Blockers / pharmacology*
  • Sodium Channels / metabolism*

Substances

  • Cytochrome P-450 Enzyme Inhibitors
  • Indazoles
  • Neuroprotective Agents
  • Protein Isoforms
  • Sodium Channel Blockers
  • Sodium Channels
  • Cytochrome P-450 Enzyme System