Pricing Availability   Qty
Description: Potent, reversible non-steroidal aromatase inhibitor
Alternative Names: CGS 20267
Chemical Name: 4,4'-(1H-1,2,4-Triazol-1-ylmethylene)bisbenzonitrile
Purity: ≥99% (HPLC)
Citations (4)

Biological Activity for Letrozole

Letrozole is a potent, reversible non-steroidal aromatase inhibitor (IC50 = 11.5 nM). Displays antitumor effects in several animal models. Suppresses the endogenous aromatase-induced proliferation of MCF-7 cells.

Compound Libraries for Letrozole

Letrozole is also offered as part of the Tocriscreen 2.0 Max and Tocriscreen FDA-Approved Drugs. Find out more about compound libraries available from Tocris.

Technical Data for Letrozole

M. Wt 285.3
Formula C17H11N5
Storage Store at +4°C
Purity ≥99% (HPLC)
CAS Number 112809-51-5
PubChem ID 3902
Smiles N#CC(C=C2)=CC=C2C(N3N=CN=C3)C1=CC=C(C#N)C=C1

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

Tocris products are intended for laboratory research use only, unless stated otherwise.

Solubility Data for Letrozole

Solvent Max Conc. mg/mL Max Conc. mM
DMSO 28.53 100

Preparing Stock Solutions for Letrozole

The following data is based on the product molecular weight 285.3. Batch specific molecular weights may vary from batch to batch due to the degree 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 3.51 mL 17.53 mL 35.05 mL
5 mM 0.7 mL 3.51 mL 7.01 mL
10 mM 0.35 mL 1.75 mL 3.51 mL
50 mM 0.07 mL 0.35 mL 0.7 mL

Molarity Calculator

Calculate the mass, volume, or concentration required for a solution.

*When preparing stock solutions always use the batch-specific molecular weight of the product found on the vial label and CoA (available online).

Reconstitution Calculator

The reconstitution calculator allows you to quickly calculate the volume of a reagent to reconstitute your vial. Simply enter the mass of reagent and the target concentration and the calculator will determine the rest.


Dilution Calculator

Calculate the dilution required to prepare a stock solution.

References for Letrozole

References are publications that support the biological activity of the product.

Mitropoulou et al (2003) Letrozole as a potent inhibitor of cell proliferation and expression of metalloproteinases (MMP-2 and MMP-9) by human epithelial breast cancer cells. Int.J.Cancer 104 155 PMID: 12569569

Bhatnagar et al (1990) Highly selective inhbition of estrogen biosynthesis by CGS 20267, a new non-steroidal aromatase inhibitor. J.Steroid Biochem.Mol.Biol. 37 1021 PMID: 2149502

Bhatnagar (2007) The discovery and mechanism of action of letr. Breast Cancer Res.Treat. 105 7 PMID: 17912633

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

View Related Products by Product Action

View all Cytochrome P450 Inhibitors

Keywords: Letrozole, Letrozole supplier, CGS20267, non-steroidal, aromatase, CYP19, inhibitors, inhibits, potent, reversible, antitumor, antitumour, CGS, 20267, Cytochrome, P450, Estrogen, and, Related, Receptors, 4382, Tocris Bioscience

4 Citations for Letrozole

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

Ruiz-Palmero et al (2016) OOE synthesized by female neurons generates sex differences in neuritogenesis. Scientific Reports 6 31891 PMID: 27553191

Xin-Ming et al (2023) Klotho Regulated by Estrogen Plays a Key Role in Sex Differences in Stress Resilience in Rats. Int J Mol Sci 24 PMID: 36674721

Tozzi et al (2015) Endogenous 17β-OE is required for activity-dependent long-term potentiation in the striatum: interaction with the DArgic system. Front Cell Neurosci 9 192 PMID: 26074768

Ali et al (2017) Isolation and characterization of a new naturally immortalized human breast carcinoma cell line, KAIMRC1. BMC Cancer 17 803 PMID: 29187162

Do you know of a great paper that uses Letrozole from Tocris? Please let us know.

Reviews for Letrozole

There are currently no reviews for this product. Be the first to review Letrozole and earn rewards!

Have you used Letrozole?

Submit a review and receive an Amazon gift card.

$50/€35/£30/$50CAN/¥300 Yuan/¥5000 Yen for first to review with an image

$25/€18/£15/$25CAN/¥75 Yuan/¥1250 Yen for a review with an image

$10/€7/£6/$10 CAD/¥70 Yuan/¥1110 Yen for a review without an image

Submit a Review