Title: Estriol
CAS Registry Number: 50-27-1
CAS Name: (16a,17b)-Estra-1,3,5(10)-triene-3,16,17-triol
Additional Names: 1,3,5-estratriene-3b,16a,17b-triol; 3,16a,17b-trihydroxy-D1,3,5-estratriene; 16a-hydroxyestradiol; follicular hormone hydrate; oestriol; trihydroxyestrin
Trademarks: Aacifemine (Aaciphar); Colpogyn (Angelini); Destriol; Gynäsan (Bastian); Hormomed (Merckle); Klimax E (Fink); Oekolp (Kade); Ortho-Gynest (Cilag); Ovesterin; Ovestin (Organon); Ovo-Vinces (Wolff); Theelol (Parke-Davis); Trophicreme (Sanofi Winthrop); Tridestrin; Triovex
Molecular Formula: C18H24O3
Molecular Weight: 288.38
Percent Composition: C 74.97%, H 8.39%, O 16.64%
Literature References: A metabolite of, and considerably less potent than the hormone estradiol, q.v. It is usually the predominant estrogenic metabolite found in urine. During pregnancy the placenta produces relatively large amounts of estriol. Isoln from human pregnancy urine: Marrian, Biochem. J. 23, 1090, 1233 (1929); probably occurs as a glycuronide: Cohen, Marrian, ibid. 29, 1577 (1935). Isoln from human placenta: Collip, Br. Med. J. II, 1080 (1930); Collip et al., Endocrinology 18, 71 (1934). Also obtained from plant sources. Isoln from pussywillows: Skarzynski, Nature 131, 766 (1933). Structure: Huffman, Lott, J. Am. Chem. Soc. 69, 1835 (1947). Crystal and molecular structure: Cooper et al., Acta Crystallogr. 25B, 814 (1969). Soly studies: Ruchelman, Howe, J. Chromatogr. Sci. 7, 340 (1969). Partial synthesis: Huffman, J. Biol. Chem. 169, 167 (1947). Syntheses: Huffman, Lott, J. Am. Chem. Soc. 71, 719 (1949); Leeds et al., ibid. 76, 2943 (1954).
Properties: Very small, monoclinic crystals from dil alc. d 1.27. mp 282°. During heating on the microscope heating stage, rearrangement of the crystal structure takes place at 270° and 275° (rate of heating, 4°/min, Kofler microscope heating stage). [a]D25 +58° ±5° (0.04 g in 1 ml dioxane). uv max: 280 nm. Precipitated by digitonin. Practically insol in water. Sol in alcohol, dioxane, chloroform, ether, vegetable oils; freely sol in pyridine, in solns of fixed alkali hydroxides.
Melting point: mp 282°
Optical Rotation: [a]D25 +58° ±5° (0.04 g in 1 ml dioxane)
Absorption maximum: uv max: 280 nm
Density: d 1.27
Derivative Type: Triacetate
Molecular Formula: C24H30O6
Molecular Weight: 414.49
Percent Composition: C 69.54%, H 7.30%, O 23.16%
Properties: Crystals from 90% alc. mp 126°.
Melting point: mp 126°
Derivative Type: 16,17-Bis(sodium hemisuccinate)
CAS Registry Number: 113-22-4
Additional Names: Estriol succinate
Trademarks: Orgastyptin (Organon); Stiptanon (Organon); Synapause (Organon)
Molecular Formula: C26H30Na2O9
Molecular Weight: 532.49
Percent Composition: C 58.64%, H 5.68%, Na 8.63%, O 27.04%
Literature References: Prepn: GB 879014 (1960 to Organon).
Therap-Cat: Estrogen.
Therap-Cat-Vet: Estrogenic hormone therapy.
Keywords: Estrogen; Steroidal.
Estrone Etafedrine Etafenone Etamiphyllin Etamycin

CAS number 50-27-1 YesY
PubChem 5756
ChemSpider 5553 YesY
UNII FB33469R8E YesY
DrugBank DB04573
KEGG C05141 YesY
MeSH Estriol
ChEBI CHEBI:27974 YesY
ATC code G03CA04,G03CC06
Jmol-3D images Image 1
Molecular formula C18H24O3
Molar mass 288.38 g mol−1
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Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Estriol (also oestriol or E3) is one of the three main estrogens produced by the human body.