Coumarin and flavone derivatives from estragon and thyme as inhibitors of chemical mediator release from RBL-2H3 Cells

Biosci Biotechnol Biochem. 2005 Jan;69(1):1-6. doi: 10.1271/bbb.69.1.


Estragon and thyme extracts showed potent inhibitory activities against chemical mediator release from rat basophilic leukemia RBL-2H3 cells. 7-Methoxycoumarin was isolated from estragon, and 5,4'-dihydroxy-6,7,3'-trimethoxyflavone, 5,4'-dihydroxy-6,7,8,3'-tetramethoxyflavone, 5-hydroxy-6,7,8,3',4'-pentamethoxyflavone and luteolin were isolated from thyme as active components. Structure-activity relationship studies among the active isolates and their related compounds indicated that the oxygen-containing functional group at the 7-position of the coumarin structure was advantageous for the inhibitory activity and that methylation of the hydroxyl group at the 4'-position of the flavone structure was disadvantageous. It was also found that coumarin derivatives inhibited an earlier step than intracellular calcium release and proteinkinase C activation, while flavones inhibited a later step or both earlier and later steps.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Artemisia / chemistry*
  • Cell Degranulation / drug effects*
  • Cell Line, Tumor
  • Coumarins / chemistry
  • Coumarins / isolation & purification*
  • Coumarins / pharmacology
  • Flavones / chemistry
  • Flavones / isolation & purification*
  • Flavones / pharmacology
  • Molecular Structure
  • Rats
  • Structure-Activity Relationship
  • Thymus Plant / chemistry*
  • beta-N-Acetylhexosaminidases / metabolism


  • Coumarins
  • Flavones
  • beta-N-Acetylhexosaminidases