Khellinone derivatives as blockers of the voltage-gated potassium channel Kv1.3: synthesis and immunosuppressive activity

J Med Chem. 2004 Apr 22;47(9):2326-36. doi: 10.1021/jm030523s.


The voltage-gated potassium channel Kv1.3 constitutes a promising new target for the treatment of T-cell-mediated autoimmune diseases such as multiple sclerosis. In this study, we report the discovery of two new classes of Kv1.3 blockers based on the naturally occurring compound khellinone, 5-acetyl-4,7-dimethoxy-6-hydroxybenzofuran: (1) khellinone dimers linked via the alkylation of the 6-hydroxy groups and (2) chalcone derivatives of khellinone formed by Claisen-Schmidt condensation of the 5-acetyl group with aryl aldehydes. In particular, the chalcone 3-(4,7-dimethoxy-6-hydroxybenzofuran-5-yl)-1-phenyl-3-oxopropene (16) and several of its derivatives inhibited Kv1.3 with K(d) values of 300-800 nM and a Hill coefficient of 2, displayed moderate selectivity over other Kv1-family K(+) channels, suppressed T-lymphocyte proliferation at submicromolar concentrations, and showed no signs of acute toxicity in mice. Because of their relatively low molecular weight and lipophilicity and their high affinity to Kv1.3, aryl-substituted khellinone derivatives represent attractive lead compounds for the development of more potent and selective Kv1.3 blocking immunosuppressants.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Benzofurans / chemical synthesis*
  • Benzofurans / chemistry
  • Benzofurans / pharmacology
  • Cell Division
  • Cell Line
  • Chalcone / analogs & derivatives
  • Chalcone / chemical synthesis*
  • Chalcone / chemistry
  • Chalcone / pharmacology
  • Chalcones
  • Humans
  • Immunosuppressive Agents / chemical synthesis*
  • Immunosuppressive Agents / chemistry
  • Immunosuppressive Agents / pharmacology
  • Ion Channel Gating
  • Kv1.3 Potassium Channel
  • Mice
  • Molecular Structure
  • Potassium Channel Blockers / chemical synthesis*
  • Potassium Channel Blockers / chemistry
  • Potassium Channel Blockers / pharmacology
  • Potassium Channels / drug effects*
  • Potassium Channels / physiology
  • Potassium Channels, Voltage-Gated*
  • Structure-Activity Relationship
  • T-Lymphocytes / cytology
  • T-Lymphocytes / drug effects
  • T-Lymphocytes / physiology
  • Toxicity Tests, Acute


  • 3-(4,7-dimethoxy-6-hydroxybenzofuran-5-yl)-1-phenyl-3-oxopropene
  • Benzofurans
  • Chalcones
  • Immunosuppressive Agents
  • KCNA3 protein, human
  • Kcna3 protein, mouse
  • Kv1.3 Potassium Channel
  • Potassium Channel Blockers
  • Potassium Channels
  • Potassium Channels, Voltage-Gated
  • Chalcone