Compound Detail

CHEMBL1444

LETROZOLE

💊 Approved Drug

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💊 Approved Drug

N#Cc1ccc(C(c2ccc(C#N)cc2)n2cncn2)cc1

ChEMBL ↗ Properties Compare Identifier

Basic Information

ChEMBL ID	CHEMBL1444
Name	LETROZOLE
Phase	Approved
Structure Type	MOL
InChI Key	HPJKCIUCZWXJDR-UHFFFAOYSA-N
Therapeutic	✓ Yes

Known Names

CGS 20267 CGS-20267 Femara Letrozol Letrozole Letrozole component of kisqali femara co-pack NSC-759652

Targets

Activities

Assay Types

PK Parameters

Publications

Known Names

Indications

Mechanisms

Molecular Properties

285.3

MW (Da)

2.66

ALogP

HBA

HBD

78.3

PSA (Å²)

0.74

QED

Ro5 Violations

Rot. Bonds

Drug Information

Molecule Type	Small molecule
First Approval	1997
Availability	Prescription
Chirality	Achiral

Routes of Administration

Oral

Flags

Natural Product

USAN Stem	-rozole
USAN Year	1993

Extended Properties

Molecular Formula	C17H11N5
MW	285.31
Aromatic Rings	3
Heavy Atoms	22
NP-Likeness	-1.17

Mechanism of Action

Mechanism	Action Type	Target	Direct	Efficacy
Cytochrome P450 19A1 inhibitor	INHIBITOR	Aromatase	✓	✓

Indications

Breast Neoplasms Breast Neoplasms Breast Neoplasms Neoplasms Neoplasms Abortion, Spontaneous Azoospermia Carcinoma, Intraductal, Noninfiltrating Endometrial Neoplasms Endometrial Neoplasms Endometrial Neoplasms Follicular Cyst Hereditary Breast and Ovarian Cancer Syndrome Hypogonadism Infertility Menopause Neoplasm Metastasis Osteoporosis Ovarian Hyperstimulation Syndrome Ovarian Neoplasms

ATC Classification

L02BG04

letrozole

Level 1: ANTINEOPLASTIC AND IMMUNOMODULATING AGENTS

Level 2: ENDOCRINE THERAPY

Activity Summary

IC50 56 meas. best 9.15

Ki 2 meas. best 10.7

EC50 1 meas.

Target Activity Profile

Target	Type	Best pChEMBL	Mean pChEMBL	Best (nM)	# Data
Aromatase CHEMBL1978	Ki	10.7	9.68	0.0	2
Aromatase CHEMBL1978	IC50	9.15	8.1492	0.7	48
MCF7 CHEMBL387	IC50	8.15	6.326	7.0	5
Cytochrome P450 11B2, mitochondrial CHEMBL2722	IC50	5.85	5.85	1420.0	1
Cytochrome P450 11B1, mitochondrial CHEMBL1908	IC50	5.58	5.58	2620.0	1

Pharmacokinetic Data

Parameter	Value	Units	Species
CL	0.57	mL.min-1.kg-1	Homo sapiens
CL	0.57	mL.min-1.kg-1	Homo sapiens
CL	0.6	mL.min-1.kg-1	Homo sapiens
CL	0.57	mL.min-1.kg-1	Homo sapiens
CL	3.0	uL.min-1.(10^6cells)-1	Homo sapiens
CL	0.58	mL.min-1.kg-1	Homo sapiens
Cmax	115.0	nM	Homo sapiens
Excretion	3.9	%	Homo sapiens
F	99.9	%	Homo sapiens
F	99.9	%	Homo sapiens
Fu	0.41	-	Homo sapiens
Fu	0.41	-	Homo sapiens
MRT	59.0	hr	Homo sapiens
T1/2	45.0	hr	Homo sapiens
T1/2	45.0	hr	Homo sapiens
Tmax	1.0	hr	Homo sapiens
Vd	1.9	L.kg-1	Homo sapiens
Vd	1.87	L.kg-1	Homo sapiens

Activity Data Samples

Top measurements by pChEMBL value

Target	Type	Rel.	Value	Units	pChEMBL	Assay	PubMed
Aromatase	Ki	=	0.02	nM	10.7	Competitive inhibition of human aromatase using dibenzylfluorescein substrate af...	22386564
Aromatase	IC50	=	0.7	nM	9.15	Inhibition of aromatase in human JEG-3 cells using Androst-4-ene-3,17-dione [1be...	36846364
Aromatase	IC50	=	0.7	nM	9.15	Inhibition of aromatase in human JEG-3 cells using Androst-4-ene-3,17-dione as s...	35834906
Aromatase	IC50	=	0.89	nM	9.05	Inhibition of aromatase activity in human JEG3 cells	18590272
Aromatase	IC50	=	0.89	nM	9.05	Inhibition of aromatase in human JEG3 cells by scintillation spectrometry	20148564
Aromatase	IC50	=	0.89	nM	9.05	Inhibition of aromatase (unknown origin) expressed in JEG-3 cells	25992880
Aromatase	IC50	=	1.0	nM	9.0	Inhibition of human aromatase coexpressed with P450 reductase by fluorimetry	22335894
Aromatase	IC50	=	1.0	nM	9.0	Inhibition of aromatase (unknown origin)	34110821
Aromatase	IC50	=	1.1	nM	8.96	Inhibition of human recombinant aromatase expressed in baculovirus infected inse...	-
Aromatase	IC50	=	1.8	nM	8.74	Inhibition of human recombinant aromatase using ARO as substrate	37037140
Aromatase	IC50	=	1.8	nM	8.74	Inhibition of recombinant human aromatase using ARO substrate/NADP+ mixture by f...	38809993
Aromatase	IC50	=	1.9	nM	8.72	Inhibition of aromatase (unknown origin) using O-benzyl fluorescein benzyl ester...	29137864
Aromatase	IC50	=	1.9	nM	8.72	Inhibition of recombinant human aromatase expressed in baculovirus infected inse...	31416738
Aromatase	IC50	=	1.9	nM	8.72	Inhibition of aromatase in human MCF-7aro cells using [1beta-3H] androstenedione...	31732252
Aromatase	IC50	=	2.0	nM	8.7	Inhibition of human aromatase using dibenzylfluorescein substrate preincubated f...	22386564
Aromatase	IC50	=	2.0	nM	8.7	Inhibition of aromatase in human breast tumor	35964426
Aromatase	Ki	=	2.2	nM	8.66	Inhibition of human aromatase-mediated conversion of [1beta3H]androstenedione to...	19072235
Aromatase	IC50	=	2.18	nM	8.66	Inhibition of recombinant human aromatase using 7-methoxy-trifluoromethylcoumari...	27567077
Aromatase	IC50	=	2.178	nM	8.66	Inhibition of recombinant human aromatase using 7-methoxy-trifluoromethylcoumari...	27567077
Aromatase	IC50	=	2.8	nM	8.55	Inhibition of human recombinant aromatase expressed in baculovirus insect cell u...	34000484

Literature References

PubMed	DOI	Target Context	# Activities
-	10.6019/CHEMBL3885881	Rattus norvegicus	270
-	10.5281/zenodo.13943903	ADMET	89
31158845	10.1038/s41586-019-1291-3	ADMET	69
22194678	10.1371/journal.pcbi.1002310	Hepatotoxicity	14
20070106	10.1021/jm901371v	Homo sapiens	8
38809993	10.1021/acs.jmedchem.4c00196	MCF7	6
-	10.1007/s00044-012-0133-8	ADMET	5
20102168	10.1021/np9004695	Aromatase	4
17580845	10.1021/jm061462b	Rattus norvegicus	4
18426954	10.1124/dmd.108.020479	ADMET	4
17287126	10.1016/j.bmc.2007.01.031	Aromatase	4
24025069	10.1021/jm400377z	Aromatase	3
20148564	10.1021/jm901705h	Rattus norvegicus	3
24345481	10.1016/j.bmc.2013.11.045	MCF7	2
22951074	10.1021/jm300930n	Aromatase	2
19445515	10.1021/jm900403j	Homo sapiens	2
-	10.1039/C2MD20072D	Cytochrome P450 11B1, mitochondrial	2
24025069	10.1021/jm400377z	NON-PROTEIN TARGET	2
19072235	10.1021/jm800945c	Aromatase	2
24025069	10.1021/jm400377z	HeLa	2

Data from ChEMBL 36 via Core Engine