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Formestane 566-48-3 Muscle Gaining USP Standard 99% Purity Steroid Powder

Categories Anti Estrogen Steroids
Brand Name: TINGYI
Model Number: 566-48-3
Certification: GMP , ISO 9001:2008
Place of Origin: CHINA
MOQ: 10g
Price: Contact Me
Payment Terms: Bank Transfer - Bitcoin - Western Union - MoneyGram
Supply Ability: 100 KG/Month
Delivery Time: 2 Working Days
Packaging Details: Disguised Package
Product Name: Formestane
CAS: 566-48-3
Appearance: White Powder
Usage: Muscle Gaining
Shipping Method: EMS, HKEMS, FEDEX, DHL, UPS, Aramex, ETC
Color: White
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Formestane 566-48-3 Muscle Gaining USP Standard 99% Purity Steroid Powder

Quick detail

Product NameFormestane
AliasLentaron, 4-hydroxyandrost-4-ene-3,17-dione
Appearanceoff-white crystalline powder
UsageAn antitumor drug. An aromatase inhibitor
Dosage250mg, 1 time every two weeks, as the arm deep intramuscular injection.
Density1.19 g/cm3
Melting Point199-202 ℃
Boiling Point475.4 ℃ at 760 mmHg
Flash Point255.4 ℃
PackingFoil bag or as requirments
GradePharmaceutical Grade
molecular structure


DescriptionWhite or Almost White Crystalline Powderwhite powder
Specific Rotation+101°~+105°+102.6°
Loss On Drying1.0%max0.27%
Melting Point153~157°C153.0~155.0°C
Organic Volatile Impuritiesmeets the requirement.Conforms
Related Substancesmeets the requirement.Conforms
Residual Solventsmeets the requirement.Conforms
Particle Size100% ≤ 20 micronsConforms
ConclusionThe specification conform with USP35 standard


Formestane is a second generation, irreversible, steroidal aromatase inhibitor. It inhibits the aromatase enzyme responsible for converting androgens to estrogens, thereby preventing estrogen production. Breast cancer may be estrogen sensitive or insensitive. A majority of breast cancers are estrogen sensitive. Estrogen sensitive breast cancer cells depend on estrogen for viability. Thus removal of estrogen from the body can be an effective treatment for hormone sensitive breast cancers.

Formestane has been targeted specifically for the treatment of postmenopausal women. Unlike premenopausal women who produce most estrogen in the ovaries, postmenopausal women produce most estrogen in peripheral tissues with the help of the aromatase enzyme. Formestane, an aromatase inhibitor, can thus help to decrease the local production of estrogen by blocking the aromatase enzyme in peripheral tissues (ie. Adispose tissue of the breast) to treat hormone sensitive breast cancer.

Product Description

A. Formestane is a synthetic steroidal substance with antineoplastic activity. Formestane binds irreversibly to and inhibits the enzyme aromatase, thereby blocking the conversion of cholesterol to pregnenolone and the peripheral aromatization of androgenic precursors into estrogens.

B. Formestane is a drug that has been previously used in breast cancer treatment. Like most drugs which have some sort of phsyique usage, athletes eventually get a hold of it. Formestane is currently one of the best legal anti-estrogens out there. It is classified as an irreversible arromatase inhibitor, meaning, it destroys the aromatase enzyme.

C. Formestane is often used to suppress estrogen production from anabolic steroids or prohormones. It also acts as a prohormone to 4-hydroxytestosterone, an active steroid which displays weak androgenic activity in addition to acting as a mild aromatase inhibitor.

Formestane has poor oral bioavailability and as such is no longer popular as many orally active aromatase inhibitors have been identified.

Formestane Dosages

The most common version of formestane sold was in a topical gel form and it was dosed at 100-200mgs per application. Users would apply it onto clean, dry skin and rub in thoroughly; usually on the thighs or upper arms. It took 1 to 5 minutes to dry.
The injectable version for both breast cancer purposes and bodybuilders is 125mgs twice per week or 250mgs once per week.

How Does Formestane Works For Breast Cancer?

By significantly reducing estrogen levels in the blood, methanesulfon may exhibit antitumor activity. In a trial involving 147 postmenopausal women and advanced breast cancer drug resistance, 22% of patients received partial response and 20% achieved disease stabilization.

In comparing the non-steroidal aromatase inhibitor anastrozole with methotrexate, it was found that anastrozole was more effective and consistent in inhibiting estrogen levels in vivo. However, these results are unproven clinical significance.

Formestane is a second generation irreversible steroid aroma inhibitor. It inhibits the aromatase responsible for converting androgen into estrogen, thereby preventing estrogen production.

Breast cancer may be estrogen-sensitive or insensitive. Most breast cancers are estrogen-sensitive. Estrogen-sensitive breast cancer cells are dependent on estrogenic activity.

Therefore, removal of estrogen from the body can become an effective treatment for hormone-sensitive breast cancer. Formestane is specially designed for the treatment of postmenopausal women.

Unlike premenopausal women who produce the most estrogen in the ovaries, postmenopausal women produce most estrogens in peripheral tissues with the help of aromatases. The aromatic compound inhibitor Formestane can help reduce the local production of estrogen by blocking peripheral tissue (ie, aromatase in breast tissue) to treat hormone-sensitive breast cancer.

Use for Bodybuilding

Formestane can lower SHBG up to 34%, which will increase free levels. SHBG (sex hormone binding globulin) is a protein that binds to sex steroids, and renders them inactive, for as long as SHBG is bound to them. There is a difference between 'free' , and 'bound' . Free testosterone is what matters, so lowering SHBG will increase 'free' testosterone. Higher means more strength, muscle mass, less body fat, better sense of well being, and libido.

The Product List

Product NameCAS No.

Testosterone Series

Testosterone Enanthate315-37-7
Testosterone Acetate1045-69-8
Testosterone Cypionate58-20-8
Testosterone Propionate57-85-2
Testosterone Phenylpropionate1045-69-8
Testosterone Isocaproate15262-86-9
Testosterone Decanoate5721-91-5
Sustanon 250
Sustanon 100
Testosterone undecanoate5949-44-0
Oral turinabo(4-Chlorodehydromethyltestosterone)2446-23-3
4-Chlorotestosterone acetate (Clostebol acetate)855-19-6
Stanolone (androstanolone)521-18-6
Mesterolone (Proviron)1424-00-6

Nandrolone Series

Nandrolone Decanoate360-70-3
Nandrolone Phenylpropionate(Durabolin)62-90-8
Nandrolone Undecylenate862-89-5
Nandrolone propionate7207-92-3
Nandrolone Cypionate
Trenbolone series
Trenbolone Acetate (Finaplix H/Revalor-H)10161-34-9
Trenbolone Enanthate(parabola)10161-33-8
Trenbolone Hexahydrobenzyl Carbonate23454-33-3

Boldone series

Boldenone Undecylenate (Equipoise)13103-34-9
boldenone cypionate106505-90-2
boldenone Acetate2363-59-9
Boldenone propionate

DHEA series

Dehydroisoandrosterone 3-acetate853-23-6
Dehydroepiandrosterone (DHEA)53-43-0
7-keto DHEA566-19-8
Drostanolone Series
Superdrol Powder (Methyl-drostanolone)3381-88-2
Drostanolone enanthate472-61-145
Drostanolone Propionate521-12-0
Methenolone Series
Methenolone enanthate303-42-4
methenolone acetate434-05-9

Oral Steroids

Methandrostenolone (Dianabol, methandienone)72-63-9
Stanozolol (Winstrol)710418-03-8
Oxandrolone (Anavar)53-39-4

Antiestrogen Series

Tamoxifen Citrate54965-24-1
Clomiphene Citrate(Clomid)50-41-9
Tamoxifen Citrate (Nolvadex)54965-24-1
Toremifene Citrate(Fareston)89778-27-8
Anastrozole (arimidex)120511-73-1

Sex Enhancers

Tadalafil (Cialis)171596-29-5
Sildenafil (Viagra)139755-83-2
Yohimbine HCl65-19-0
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