Norendoxifen

Norendoxifen
Clinical data
Other names	4-Hydroxy-N,N-didesmethyltamoxifen
Identifiers
	IUPAC name 4-[(Z)-1-[4-(2-Aminoethoxy)phenyl]-2-phenylbut-1-enyl]phenol;
CAS Number	1217237-98-3 ;
PubChem CID	68037237;
DrugBank	DBMET00963;
ChemSpider	32817000;
UNII	51GJD354B5;
ChEMBL	ChEMBL2386284;
CompTox Dashboard (EPA)	DTXSID701337073 ;
Chemical and physical data
Formula	C24H25NO2
Molar mass	359.469 g·mol−1
3D model (JSmol)	Interactive image;
	SMILES CCC(=C(c1ccc(cc1)O)c2ccc(cc2)OCCN)c3ccccc3;
	InChI InChI=1S/C24H25NO2/c1-2-23(18-6-4-3-5-7-18)24(19-8-12-21(26)13-9-19)20-10-14-22(15-11-20)27-17-16-25/h3-15,26H,2,16-17,25H2,1H3; Key:YCQBLTPGQSYLHD-UHFFFAOYSA-N;

Norendoxifen, also known as 4-hydroxy-N,N-didesmethyltamoxifen, is a nonsteroidal aromatase inhibitor (AI) of the triphenylethylene group that was never marketed.

It is an active metabolite of the selective estrogen receptor modulator (SERM) tamoxifen. Unlike tamoxifen, norendoxifen is not a SERM, and instead has been found to act as a potent and selective competitive inhibitor of aromatase (K_i = 35 nM). Drugs with dual SERM and AI activity, such as 4'-hydroxynorendoxifen, have been developed from norendoxifen, and may have therapeutic potential as antiestrogens in the treatment of estrogen receptor-positive breast cancer.