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Updated: May 28, 2026

Detecting Estrogenic Ligands in Personal Care Products using a Yeast Estrogen Screen Optimized for the Undergraduate Teaching Laboratory
Published on: January 1, 2018
Development of 2,3,5-triaryl-1H-pyrroles as estrogen receptor α selective ligands
Anja Schäfer1, Anja Wellner, Martin Strauss
1Institut für Pharmazie, Freie Universität Berlin, Königin-Luise-Str. 2+4, 14195 Berlin, Germany.
Abstract:
1-Alkyl-2,3,5-triaryl-1H-pyrroles (for which alkyl=methyl, ethyl, n-propyl, or 2-methylpropyl) were tested for stability, estrogen receptor (ER) binding, and inhibition of tumor cell growth. These pyrroles (type B) showed higher stability in aqueous solution than their 1,2,4-triaryl-1H-pyrrole congeners (type A pyrroles), exclusive ERα binding (no ERβ interaction), and a hormonal profile of partial agonists at ERα. The most potent compound, 1-(2-methylpropyl)-2,3,5-tris(4-hydroxyphenyl)-1H-pyrrole (5 d), was less active than the lead structure 1,3,5-tris(4-hydroxyphenyl)-4-propyl-1H-pyrazole (PPT) in MCF-7 cells stably transfected with the plasmid EREwtcluc (MCF-7/2a), but more potent in U2-OS/α cells. Furthermore, 5 d showed weak anti-estrogenic properties (IC50=310 nM). An additional propyl chain at C4 decreased the stability and pharmacological effects.
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