Catalog Number: 4382
Alternate Names: CGS 20267
Chemical Name: 4,4'-(1H-1,2,4-Triazol-1-ylmethylene)bisbenzonitrile
Biological Activity
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.
Technical Data
  • M.Wt:
  • Formula:
  • Solubility:
    Soluble to 100 mM in DMSO
  • Purity:
  • Storage:
    Store at +4°C
  • CAS No:
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.
Background References
  1. Letrozole as a potent inhibitor of cell proliferation and expression of metalloproteinases (MMP-2 and MMP-9) by human epithelial breast cancer cells.
    Mitropoulou et al.
    Int.J.Cancer, 2003;104:155
  2. Highly selective inhbition of estrogen biosynthesis by CGS 20267, a new non-steroidal aromatase inhibitor.
    Bhatnagar et al.
    J.Steroid Biochem.Mol.Biol., 1990;37:1021
  3. The discovery and mechanism of action of letrozole.
    Breast Cancer Res.Treat., 2007;105:7

The citations listed below are publications that use Tocris products. Selected citations for Letrozole include:

Showing Results 1 - 2 of 2

  1. Oestradiol�synthesized�by�female�neurons�generates�sex�differences�in�neuritogenesis.
    Authors: Ruiz-Palmero Et al.
    Scientific Reports
  2. Endogenous 17β-estradiol is required for activity-dependent long-term potentiation in the striatum: interaction with the dopaminergic system.
    Authors: Tozzi Et al.
    Front Cell Neurosci
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