Estrone sulfate

Estrone sulfate

Clinical data
Synonyms	E1S; Estrone 3-sulfate
Routes of administration	By mouth
Drug class	Estrogen; Estrogen ester
Pharmacokinetic data
Biological half-life	12 hours
Identifiers
IUPAC name [(8R,9S,13S,14S)-13-methyl-17-oxo-7,8,9,11,12,14,15,16-octahydro-6H-cyclopenta[a]phenanthren-3-yl] hydrogen sulfate
CAS Number	481-97-0 Y 438-67-5 (sodium) 7280-37-7 (piperazine)
PubChem CID	3001028
IUPHAR/BPS	4749
DrugBank	DB04574 Y
ChemSpider	2272513 Y
UNII	QTL48N278K
ChEBI	CHEBI:17474 Y
ChEMBL	CHEMBL494753 Y
ECHA InfoCard	100.006.888
Chemical and physical data
Formula	C18H22O5S
Molar mass	350.43 g/mol
3D model (JSmol)	Interactive image
SMILES O=S(=O)(O)Oc1cc4c(cc1)[C@H]3CC[C@@]2(C(=O)CC[C@H]2[C@@H]3CC4)C
InChI InChI=1S/C18H22O5S/c1-18-9-8-14-13-5-3-12(23-24(20,21)22)10-11(13)2-4-15(14)16(18)6-7-17(18)19/h3,5,10,14-16H,2,4,6-9H2,1H3,(H,20,21,22)/t14-,15-,16+,18+/m1/s1 Y Key:JKKFKPJIXZFSSB-CBZIJGRNSA-N Y

Estrone sulfate (E1S), or estrone 3-sulfate, is a natural, endogenous steroid and an estrogen ester and conjugate. It is a component of conjugated estrogens (Premarin) and esterified estrogens, and is also used as estropipate (piperazine estrone sulfate).

E1S itself is biologically inactive, with less than 1% of the relative binding affinity of estradiol for the ERα and ERβ, but it can be converted by steroid sulfatase (also called estrogen sulfatase) into estrone, which is an estrogen. Simultaneously, estrogen sulfotransferases convert estrone to E1S, resulting in an equilibrium between the two steroids in various tissues. E1S is thought to serve as a long-lasting reservoir for estrone and estradiol in the body. In addition to its biological role, as the sodium salt, sodium estrone sulfate, E1S is the primary active estrogen in conjugated estrogens (Premarin) and esterified estrogens. Aside from its presence in these estrogen formulations, E2S is not available as a commercial pharmaceutical drug. However, it is available as estropipate (piperazine estrone sulfate), a salt of E1S and piperazine.