CAS No.50-50-0 Estradiol benzoate

Estradiol benzoate

Name Estradiol benzoate
CAS Registry Number 50-50-0
Synonyms (17beta)-Estra-1,3,5(10)-triene-3,17-diol 3-benzoate;1,3,5(10)-Estratriene-3,17-diol-3-benzoate;1,3,5(10)-Oestratriene-3,17-beta-diol 3-benzoate;1,3,5(10)-oestratriene-3,17-beta-diol3-benzoate;17beta-Estradiol monobenzoate;17-beta-estradiolmonobenzoate;17-beta-Oestradiol 3-benzoate;17-beta-oestradiol3-benzoate
Molecular Structure Estradiol benzoate   50-50-0
Molecular Formula C25H28O3
Molecular Weight 376.49
mp: 191-198 ℃(lit.)
Hazard Codes: Details
Risk Statements: 60-61-40
Safety Statements: 53-22-36/37/39-45

CAS 50-50-0 Wiki / 50-50-0 MSDS

Estradiol benzoate
Estradiol benzoate.svg
Clinical data
Pronunciation /ˌɛstrəˈdl ˈbɛnzt/ ES-trə-DYE-ohl BEN-zoh-ayt
Trade names Agofollin, Benovocyclin, Benzofoline, Dimenformon, Progynon-B, many others
Routes of
Intramuscular injection
ATC code
  • G03CA03 (WHO)
Legal status
Legal status
  • In general: ℞ (Prescription only)
Pharmacokinetic data
Bioavailability Intramuscular: 100%[citation needed]
Metabolism Cleavage via esterases in the liver, blood, and tissues[1]
Metabolites Estradiol, benzoic acid,[1] and metabolites of estradiol
Duration of action 4–5 days (5 mg i.m.)[2]
Synonyms 17β-Estradiol-3-benzoate; NSC-9566; Benzhormovarine, Difollisterol, Follicormon, Follidimyl, Follidrinbensoat, Oestro-Vitis, Oestroform
CAS Number
  • 50-50-0
PubChem CID
  • 222757
  • DBSALT000066
  • 193412
  • 1S4CJB5ZGN
  • D01953
  • CHEBI:77006
  • CHEMBL282575
ECHA InfoCard 100.000.040
Chemical and physical data
Formula C25H28O3
Molar mass 376.488 g/mol
3D model (JSmol)
  • Interactive image

Estradiol benzoate (EB, E2B) (INN) (brand name Progynon-B, many others), or oestradiol benzoate (BAN), is a synthetic, steroidal estrogen and an estrogen ester – specifically, the 3-benzoate ester of estradiol – which is marketed in Europe and elsewhere throughout the world.[3][4][5] It acts as a prodrug of estradiol, and hence, is considered to be a natural, bioidentical form of estrogen.[1] Estradiol benzoate was introduced in 1936 and was one of the first forms of estrogen to be marketed.[6][7] Along with estradiol dipropionate, it was one of the most widely used estradiol esters prior to the 1950s.[8] However, estradiol benzoate is now little used, having largely been superseded by longer-acting esters of estradiol like estradiol valerate and estradiol cypionate that require less frequent administration.[2]