Title: Letrozole
CAS Registry Number: 112809-51-5
CAS Name: 4,4¢-(1
H-1,2,4-Triazol-1-ylmethylene)bisbenzonitrile
Synonyms: 1-[bis(4-cyanophenyl)methyl]-1,2,4-triazole; 4-[1-(4-cyanophenyl)-1-(1,2,4-triazol-1-yl)methyl]benzonitrile
Manufacturers' Codes: CGS-20267
Trademarks: Femara (Novartis)
Molecular Formula: C17H11N5
Molecular Weight: 285.30
Percent Composition: C 71.57%, H 3.89%, N 24.55%
Literature References: Nonsteroidal aromatase inhibitor; structurally related to fadrozole,
q.v. Prepn: R. M. Bowman
et al., EP 236940;
eidem, US 4978672 (1987, 1990 both to Ciba-Geigy). Pharmacology: A. S. Bhatnagar
et al., J. Steroid Biochem. Mol. Biol. 37, 1021 (1990). Clinical suppression of estrogen biosynthesis: L. M. Demers
et al., ibid. 44, 687 (1993). EIA and HPLC determn in biological fluids: C. U. Pfister
et al., J. Pharm. Sci. 83, 520 (1994). Clinical evaluation in breast cancer: A. Lipton
et al., Cancer 75, 2132 (1995). Review of clinical efficacy: P. E. Goss, R. E. Smith,
Expert Rev. Anticancer Ther. 2, 249-260 (2002).
Properties: mp 181-183°.
Melting point: mp 181-183°
Therap-Cat: Antineoplastic.
Keywords: Antineoplastic (Hormonal); Aromatase Inhibitors; Aromatase Inhibitors.