PCT / AI / SERM

Letrozole

CAS 112809-51-5
Formula C₁₇H₁₁N₅
Half-life 2 days (oral)

Chemical Identity

CAS Number	`112809-51-5`
IUPAC Name	4,4'-(1H-1,2,4-triazol-1-ylmethylene)dibenzonitrile
Molecular Formula	C₁₇H₁₁N₅
Molecular Weight	285.30 g/mol
SMILES	`N#CC1=CC=C(C=C1)C(N2C=NC=N2)C3=CC=C(C=C3)C#N`
InChIKey	`HPJKCIUCZWXJDR-UHFFFAOYSA-N`
Melting Point	181-183 °C
Solubility	Freely soluble in dichloromethane; slightly soluble in ethanol; practically insoluble in water
Half-life	2 days (oral)

Pharmacological Profile

Aromatisation	None
Hepatotoxicity	Low

Known trade names

Femara
Letrozol
Femar

External references

PubChem CID 3902
PubMed clinical literature
Wikipedia overview

Data sourced from peer-reviewed pharmacological literature and authoritative chemical databases (PubChem, DrugBank, ChEBI). Provided for identification and research reference only — not medical advice.