Estrogen natural

Estrogens, Natural, the Determination and Significance of (Brown), 3, 158 Flame Photometry (MacIntyre), 4, 1 Flocculation Tests and their Application to the Study of Liver Disease (Reinhold), 3, 84... 

Estrogens Natural Estradioi Conjugated equine estrogens Estrone, estrid... 

Finally the chemical aromatization of Ring A which occurs in nature in the biosynthesis of estrogens must be mentioned. It can be done by thermal cleavage of the C-19 methyl group in 1,4-dien-3-ones (H.H. Inhoffen, 1940 C. Djerassi, 1950) and was later achieved at lower temperatures with lithium — biphenyl in THF (H.L. Dryden, Jr., 1964). 

Miscellaneous Pharmaceutical Processes. Solvent extraction is used for the preparation of many products that ate either isolated from naturally occurring materials or purified during synthesis. Among these are sulfa dmgs, methaqualone [72-44-6] phenobarbital [50-06-6] antihistamines, cortisone [53-06-5] estrogens and other hormones (qv), and reserpine [50-55-5] and alkaloids (qv). Common solvents for these appHcations are chloroform, isoamyl alcohol, diethyl ether, and methylene chloride. Distribution coefficient data for dmg species are important for the design of solvent extraction procedures. These can be determined with a laboratory continuous extraction system (AKUEVE) (244). 

Classification of the anabolic steroids is based on chemical stmctures and associated actions. A review of the biosynthesis and metabolism of the naturally occurring estrogens and androgens is available (1). Names, descriptions, approval dates, and recommended doses of the commercial products are found in References 1, 8, and 9. Although steroids may be orally active, the FDA approved mode of adrninistration is the subcutaneous implant. Effective dose is lower with implant rather than oral adrninistration. 

Estrogens are a group of naturally occurring steroid sex hormones which are characterized by their ability to induce estms in the female mammal. They are derivatives of the planar tetracycHc stmcture estra-l,3,5(10)-trien-3-ol [53-63-4](V) and the three principal estrogens in humans are estrone [56-16-7] (E ) (2), estradiol [50-28-2] (E2) (3), andestriol [50-27-1] (E ) (4). 

The two synthetic steroidal estrogens which have attained the greatest degree of therapeutic use are ethinyl estradiol [57-63-6] (EE) (5) and its 3-methyl ether, mestranol [72-33-3]((5). In contrast to the naturally occurring estrone derivatives, these acetylenic analogues are orally active and are the main estrogenic components of combination oral contraceptives (see Contraceptives) and certain estrogen replacement products. 

Steroidal and Nonsteroidal Estrogens. Modification of the basic steroid skeleton and the nature of the functional groups in the B, C, and D rings while maintaining the phenoHc A-ring has continued to be a primary approach in the development of new estrogens with unique biological profiles. 

The structurally simplest steroids, the aromatic A ring estrogens, have ironically proven most difficultly accessible because this aromatic ring is not found in any of the plant sterols available in commercial quantities. The main task of partial synthesis from naturally occurring material thus becomes... 

A major obstacle to the use of naturally occurring estrogens for the purpose of contraception was extensive first-pass hepatic metabolism and hence inactivation of the compounds when given orally. The addition of an ethinyl group at the 17 position made estradiol orally active. Ethinyl estradiol is a potent oral estrogen and... 

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