title: Structure-activity relationship study to understand the estrogen receptor-dependent gene activation of aryl- and alkyl-substituted 1H-imidazoles.
abstract: A series of C5-substituted 1,2,4-triaryl-1H-imidazoles was synthesized. Their gene-activating properties were determined on estrogen receptor alpha positive MCF-7 breast cancer cells, stably transfected with the plasmid EREwtcluc (MCF-7-2a cells). The influence of 4-OH and 2-Cl substituents on the phenyl rings as well as the significance of a methyl, ethyl, or phenyl group at C5 on the estrogen receptor binding and the resulting gene activation in MCF-7-2a cells was studied. The alkyl and aryl groups at C5 of 1,2,4-tris(4-hydroxyphenyl)-1H-imidazole 1 increased the transactivation, while chlorine atoms on the phenyl rings diminished this effect. 5-Ethyl-1,2,4-tris(4-hydroxyphenyl)-1H-imidazole 9 was identified as the most active compound. Its excellent transcriptional activity did not only depend on the C5 ethyl group, but also on the three hydroxyl groups of the phenyl rings. Compounds (11-14) with a reduced number of hydroxyl groups displayed distinctly lower gene activation.
authors.affiliation: Institute of Pharmacy, Free University of Berlin, Königin-Luise Strasse 2+4, D-14195 Berlin, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Wiglenda
authors.forename: Ronald
authors.initials: R
authors.lastname: Gust
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D047628:Estrogen Receptor alpha / Q000378:metabolism / Q000502:physiology*; D005260:Female; D006801:Humans; D007093:Imidazoles / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D066298:In Vitro Techniques; D008958:Models, Molecular; D010636:Phenols / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D011869:Radioligand Assay; D013329:Structure-Activity Relationship; D015533:Transcriptional Activation; D014599:Uterus / Q000378:metabolism
chemical_list: C519514:5-ethyl-1,2,4-tris(4-hydroxyphenyl)-1H-imidazole; D047628:Estrogen Receptor alpha; D007093:Imidazoles; D010636:Phenols