Pipendoxifene

Pipendoxifene (INN; developmental code ERA-923) is a nonsteroidal selective estrogen receptor modulator (SERM) that was under development by Ligand Pharmaceuticals and Wyeth-Ayerst Laboratories (now Wyeth) for the treatment of breast cancer but was not marketed.^[1][2][3] It is a member of the 2-phenylindole group of SERMs and is structurally related to zindoxifene and the marketed bazedoxifene.^[2][3] The drug reached phase II clinical trials before its development was discontinued.^[1][2] It was synthesized at the same time as bazedoxifene and was intended as a backup drug for bazedoxifene, only to be developed further if bazedoxifene had failed in clinical trials.^[1][2] No further development was reported after 2002 and it was formally announced that development had been terminated in November 2005.^[1][4]

Pipendoxifene

Clinical data
Other names	ERA-923
Identifiers
IUPAC name 2-(4-hydroxyphenyl)-3-methyl-1-[[4-(2-piperidin-1-ylethoxy)phenyl]methyl]indol-5-ol
CAS Number	198480-55-6
PubChem CID	6433099
ChemSpider	4938287
UNII	TPC5Q8496G
ChEMBL	ChEMBL44426
CompTox Dashboard (EPA)	DTXSID40870209
Chemical and physical data
Formula	C29H32N2O3
Molar mass	456.586 g·mol−1
3D model (JSmol)	Interactive image
SMILES CC1=C(N(C2=C1C=C(C=C2)O)CC3=CC=C(C=C3)OCCN4CCCCC4)C5=CC=C(C=C5)O
InChI InChI=1S/C29H32N2O3/c1-21-27-19-25(33)11-14-28(27)31(29(21)23-7-9-24(32)10-8-23)20-22-5-12-26(13-6-22)34-18-17-30-15-3-2-4-16-30/h5-14,19,32-33H,2-4,15-18,20H2,1H3 Key:JICOGKJOQXTAIP-UHFFFAOYSA-N

Unlike the SERM raloxifene, pipendoxifene is devoid of uterotrophic activity in immature/ovariectomized rodents.^[3][5]