Absorption, Distribution and Excretion
Absorbed after oral administration. Metabolism/Metabolites Primarily metabolized to the parent compound ethinylestradiol. Ethinylestradiol is metabolized in the liver. Quantitative analysis shows that the main metabolic pathway of ethinylestradiol in rats and humans is aromatic hydroxylation, which is the same as the metabolic pathway of natural estrogens.

Li J, Chen F, Chen Y, Wang Z. Mitochondrial- and Fas-L-mediated pathways involved in quinestrol induced spermatogenic apoptosis in adult rat testes. Toxicol Mech Methods. 2014 Dec;24(9):609-15. doi: 10.3109/15376516.2014.970680. Epub 2014 Oct 10. Review. PubMed PMID: 25258304.

Quinestrol is a 17-hydroxysteroid and a terminal alkyne compound. It is an isoestrone functionally related to 17β-estradiol. It is the 3-cyclopentyl ether of ethinylestradiol. Quinestrol is only found in individuals who have used or taken this drug. Estrogen diffuses to target cells and interacts with protein receptors (estrogen receptors). Estrogen interacts with target cell receptors. When an estrogen receptor binds to its ligand, it can enter the nucleus of the target cell and regulate gene transcription, leading to the formation of messenger RNA (mRNA). mRNA interacts with ribosomes to produce specific proteins that express the effects of estradiol on target cells. Estrogen can increase the synthesis of sex hormone-binding globulin (SHBG), thyroid-binding globulin (TBG), and other serum proteins in the liver and inhibit the secretion of follicle-stimulating hormone (FSH) from the anterior pituitary gland. Target cells include the female reproductive tract, mammary glands, hypothalamus, and pituitary gland. Estrogen increases the synthesis of sex hormone-binding globulin (SHBG), thyroid-binding globulin (TBG), and other serum proteins in the liver, and inhibits the secretion of follicle-stimulating hormone (FSH) from the anterior pituitary gland. The combined use of estrogen and progesterone can suppress the hypothalamic-pituitary system, reducing the secretion of gonadotropin-releasing hormone (GnRH).
Ethinyl estradiol 3-cyclopentyl ether. After absorption from the gastrointestinal tract, this drug is stored in adipose tissue, released slowly, and primarily metabolized to its parent compound. It was previously used in estrogen replacement therapy. (From JAMA Drug Evaluation Annals, 1992, p. 1011)
Drug Indications

Used in hormone replacement therapy to treat menopausal symptoms, such as hot flashes. Also used to treat breast and prostate cancer.
Mechanism of Action

Estrogen diffuses to target cells and interacts with protein receptors (estrogen receptors). After binding to receptors on target cells, estrogen enters the target cell nucleus, regulating gene transcription and forming messenger RNA (mRNA). mRNA interacts with ribosomes to produce specific proteins that express the effects of estradiol on target cells. Estrogen increases the synthesis of sex hormone-binding globulin (SHBG), thyroid-binding globulin (TBG), and other serum proteins in the liver, and inhibits the secretion of follicle-stimulating hormone (FSH) from the anterior pituitary gland. Its target cells include the female reproductive tract, mammary glands, hypothalamus, and pituitary gland. The combined use of estrogen and progesterone can suppress the hypothalamic-pituitary system, reducing the secretion of gonadotropin-releasing hormone (GnRH).

C25H32O2

364.5204

364.24

152-43-2

9046

White to off-white solid powder

1.2±0.1 g/cm3

502.5±50.0 °C at 760 mmHg

107 - 108ºC

218.8±24.4 °C

0.0±1.4 mmHg at 25°C

1.596

6.67

1

2

3

27

613

5

C[C@]12CC[C@H]3[C@H]([C@@H]1CC[C@]2(C#C)O)CCC4=C3C=CC(=C4)OC5CCCC5

PWZUUYSISTUNDW-UHFFFAOYSA-N

InChI=1S/C25H32O2/c1-3-25(26)15-13-23-22-10-8-17-16-19(27-18-6-4-5-7-18)9-11-20(17)21(22)12-14-24(23,25)2/h1,9,11,16,18,21-23,26H,4-8,10,12-15H2,2H3

(8R,9S,13S,14S,17R)-3-cyclopentyloxy-17-ethynyl-13-methyl-7,8,9,11,12,14,15,16-octahydro-6H-cyclopenta[a]phenanthren-17-ol

W-3566W 3566W3566Estrovis Quinestrolum Estrovister Plestrovis Eston Ethinyl Estradiol 3 Cyclopentyl Ether Ethinyl Estradiol 3-Cyclopentyl Ether

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~250 mg/mL (~685.83 mM)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)