ER 50891

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Cat.No. 3823 - ER 50891 | C29H24N2O2 | CAS No. 187400-85-7
Description: Selective RARα antagonist
Chemical Name: 4-[5-[8-(1-Methylethyl)-4-phenyl-2-quinolinyl]-1H-pyrrolo-2-benzoic acid
Purity: ≥99% (HPLC)
Citations (1)

Biological Activity

Antagonist of RARα receptors (IC50 = 31.2 nM). Displays selective affinity for RARα (relative IC50 values are 1.8, 432 and 535 nM for RARα, RARγ and RARβ respectively).

Compound Libraries

ER 50891 is also offered as part of the Tocriscreen Plus. Find out more about compound libraries available from Tocris.

Technical Data

M. Wt 432.51
Formula C29H24N2O2
Storage Store at RT
Purity ≥99% (HPLC)
CAS Number 187400-85-7
PubChem ID 10094345
Smiles CC(C)C1=C2C(C(C3=CC=CC=C3)=CC(C4=CC=C(C5=CC=C(C(O)=O)C=C5)N4)=N2)=CC=C1

The technical data provided above is for guidance only. For batch specific data refer to the Certificate of Analysis.

All Tocris products are intended for laboratory research use only.

Solubility Data

Solvent Max Conc. mg/mL Max Conc. mM
DMSO 43.25 100

Preparing Stock Solutions

The following data is based on the product molecular weight 432.51. Batch specific molecular weights may vary from batch to batch due to solvent of hydration, which will affect the solvent volumes required to prepare stock solutions.

Select a batch to recalculate based on the batch molecular weight:
Concentration / Solvent Volume / Mass 1 mg 5 mg 10 mg
1 mM 2.31 mL 11.56 mL 23.12 mL
5 mM 0.46 mL 2.31 mL 4.62 mL
10 mM 0.23 mL 1.16 mL 2.31 mL
50 mM 0.05 mL 0.23 mL 0.46 mL

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Product Datasheets

Safety Datasheet


References are publications that support the products' biological activity.

Kikuchi et al (2001) Syntheses and evaluation of quinoline derivatives as novel retinoic acid receptor α antagonists. Bioorg.Med.Chem.Lett. 11 1215 PMID: 11354380

Ren et al (2005) Impaired retinoic acid (RA) signal leads to RARβ2 epigenetic silencing and RA resistance. Mol.Cell.Biol. 25 10591 PMID: 16287870

Somenzi et al (2007) Disruption of retinoic acid receptor alpha reveals the growth promoter face of retinoic acid. PLoS ONE 9 e836 PMID: 17786207

If you know of a relevant reference for ER 50891, please let us know.

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1 Citation for ER 50891

Citations are publications that use Tocris products. Selected citations for ER 50891 include:

Centritto et al (2015) Cellular and molecular determinants of all-trans retinoic acid sensitivity in breast cancer: Luminal phenotype and RARĪ± expression. J Reprod Dev 7 950 PMID: 25888236

Do you know of a great paper that uses ER 50891 from Tocris? If so please let us know.

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Retinoid Receptors Scientific Review

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Pathways for ER 50891


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