title: Coumarin and flavone derivatives from estragon and thyme as inhibitors of chemical mediator release from RBL-2H3 Cells.
abstract: 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.
authors.affiliation: National Food Research Institute, Tsukuba, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Watanabe
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Shinmoto
authors.forename: Tojiro
authors.initials: T
authors.lastname: Tsushida
mesh_terms: D000818:Animals; D019306:Artemisia / Q000737:chemistry*; D015550:Cell Degranulation / Q000187:drug effects*; D045744:Cell Line, Tumor; D003374:Coumarins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D047309:Flavones / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D015394:Molecular Structure; D051381:Rats; D013329:Structure-Activity Relationship; D046930:Thymus Plant / Q000737:chemistry*; D001619:beta-N-Acetylhexosaminidases / Q000378:metabolism
chemical_list: D003374:Coumarins; D047309:Flavones; D001619:beta-N-Acetylhexosaminidases