Title: Coumestrol
CAS Registry Number: 479-13-0
CAS Name: 3,9-Dihydroxy-6H-benzofuro[3,2-c][1]benzopyran-6-one
Additional Names: 2-(2,4-dihydroxyphenyl)-6-hydroxy-3-benzofurancarboxylic acid d-lactone; 7¢,6-dihydroxycoumarino(3¢,4¢,3,2)coumarone
Molecular Formula: C15H8O5
Molecular Weight: 268.22
Percent Composition: C 67.17%, H 3.01%, O 29.83%
Literature References: An estrogenic factor occurring naturally in forage crops, esp in ladino clover (Trifolium repens L.), strawberry clover (T. fragiferum L.) and alfalfa (Medicago sativa L., Leguminosae). Isoln: Bickoff et al., J. Agric. Food Chem. 6, 536 (1958); Bickoff, Booth, US 2890116 (1959 to U.S.A.). Structure: Bickoff et al., J. Am. Chem. Soc. 80, 3969 (1958). Synthesis: Emerson, Bickoff, ibid. 4381; US 2884427 (1959 to U.S.A.); Jurd, Tetrahedron Lett. 1963, 1151; Kappe, Brandner, Z. Naturforsch. 29B, 292 (1974). Biosynthesis: Grisebach, Barz, Chem. Ind. (London) 1963, 690.
Properties: Crystals, mp 385°. Sublimes at 325°; sublimes in high vacuum at about 175°. uv max (methanol): 208, 243, 343 nm. Exhibits bright blue fluorescence in neutral or acid soln, greenish-yellow fluorescence in strong alkali. Absorption and fluorescence spectra: O. S. Wolfbeis, K. Schaffner, Photochem. Photobiol. 32, 143 (1980). Practically insol in water at acid and neutral pH, in petr ether. Sparingly sol in water at alkaline pH (pH 11-12); slightly sol in methanol, chloroform, ether; very slightly sol in carbon tetrachloride, benzene.
Melting point: mp 385°
Absorption maximum: uv max (methanol): 208, 243, 343 nm
Derivative Type: Diacetate
Molecular Formula: C19H12O7
Molecular Weight: 352.29
Percent Composition: C 64.78%, H 3.43%, O 31.79%
Properties: Crystals from acetic acid, mp 237°.
Melting point: mp 237°
Derivative Type: Dimethyl ether
Molecular Formula: C17H12O5
Molecular Weight: 296.27
Percent Composition: C 68.92%, H 4.08%, O 27.00%
Properties: Crystals from methanol, mp 198°.
Melting point: mp 198°
Coumetarol Coumingine Coumithoate Creolin Creosol

CAS number 479-13-0 YesY
PubChem 5281707
ChemSpider 4445024 YesY
KEGG C10205 YesY
Jmol-3D images Image 1
Image 2
Molecular formula C15H8O5
Molar mass 268.22102
Melting point 385 °C (decomp)[1]
 N (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Coumestrol is a natural organic compound in the class of phytochemicals known as coumestans. It has garnered research interest because of its estrogenic activity and its prevalence in some foods, such as soybeans.

Coumestrol was first identified by E. M. Bickoff in alfalfa in 1957.[2] It has since be found in a variety of legumes, soybeans, brussels sprouts, and spinach. Clover and soybeans have the highest concentrations.[3]

Coumestrol is a phytoestrogen, mimicking the biological activity of estrogens. Coumestrol has about the same binding affinity for the ER-β estrogen receptor as 17β-estradiol, but much less affinity for 17α-estradiol, although the estrogenic potency of coumestrol at both receptors is much less than that of 17β-estradiol.[4]

The chemical shape of coumestrol orients its two hydroxy groups in the same position as the two hydroxy groups in estradiol, allowing it to inhibit the activity of aromatase and hydroxysteroid dehydrogenase.[5] These enzymes are involved in the biosynthesis of steroid hormones, and inhibition of these enzymes results in the modulation of hormone production.[3]