1U3S: Crystal Structure Of Estrogen Receptor Beta Complexed With Way-797

New diphenolic azoles as highly selective estrogen receptor-beta agonists are reported. The more potent and selective analogues of these series have comparable binding affinities for ERbeta as the natural ligand 17beta-estradiol but are >100-fold selective over ERalpha. Our design strategy not only followed a traditional SAR approach but also was supported by X-ray structures of ERbeta cocrystallized with various ligands as well as molecular modeling studies. These strategies enabled us to take advantage of a single conservative residue substitution in the ligand-binding pocket, ERalpha Met(421) --> ERbeta Ile(373), to optimize ERbeta selectivity. The 7-position-substituted benzoxazoles (Table 5) were the most selective ligands of both azole series, with ERB-041 (117) being >200-fold selective for ERbeta. The majority of ERbeta selective agonists tested that were at least approximately 50-fold selective displayed a consistent in vivo profile: they were inactive in several models of classic estrogen action (uterotrophic, osteopenia, and vasomotor instability models) and yet were active in the HLA-B27 transgenic rat model of inflammatory bowel disease. These data suggest that ERbeta-selective agonists are devoid of classic estrogenic effects and may offer a novel therapy to treat certain inflammatory conditions.
PDB ID: 1U3SDownload
MMDB ID: 34083
PDB Deposition Date: 2004/7/22
Updated in MMDB: 2012/12
Experimental Method:
x-ray diffraction
Resolution: 2.5  Å
Source Organism:
synthetic construct
Similar Structures:
Biological Unit for 1U3S: tetrameric; determined by author and by software (PISA)
Molecular Components in 1U3S
Label Count Molecule
Proteins (4 molecules)
Estrogen Receptor Beta(Gene symbol: ESR2)
Molecule annotation
Steroid Receptor Coactivator-1
Molecule annotation
Chemicals (2 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB