Estrogen structure

Fig. (5). Structural criteria that enhance the estrogenic activity of flavonoids. I, II Criteria based on the hydroxyl moiety pattern [47, 48, 49]. Ill, IV Criteria based on the simulation of a natural estrogen structure [50, 51].

What is the pharmacologic purpose of the alterations in estrogen structure ... 

Another structural type is chromenes. Centchroman [31477-60-8]is a pyrrolidinoethoxyplienyl chromane which is a potent antiestrogen with weak estrogenic activity. In India, it is used as a weekly contraceptive pih based on its reported abiUty to inhibit the uterine preparation for the attachment of the fertilized ova to the wall of the utems (see Contraceptives) (31). 

Xenobiotic induced disruption of female fertility follows essentially the same pattern as that of the male and can be caused by changes in pituitary-hypothalamic function, primary disruption of ovarian structure or hormone secretion, or changes in the rate of hormone deactivation. In addition, there may be changes in the synthesis of estrogen induced production of the yolk protein by the liver (vitellogenesis), which in turn can lead to failure to lay down sufficient yolk in the developing oocytes. Vitellogenesis provides a valuable biomarker for endocrine dysfunction in both sexes,but is more properly considered as part of the liver function. 

Schwabe, J.W.R., et al. The crystal structure of the estrogen receptor DNA-binding domain bound to DNA how receptors discriminate between their response elements. Cell 75 567-578, 1993. 

The great variety of structures that have by now been shown to exhibit estrogenic activity leads to the suspicion that the estrogen receptor may be unusually nonspecific compared to receptors for other steroid hormones. 

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... 

Therapeutic Function Estrogen used in hormone therapy for prostate cancer Chemical Name 4,4 -(1,2-Diethyl-1,1-ethenediyl)bisphenol-bis(dihydrogen phosphate) Common Name Fosfestrol Structural Formula ... 

Therapeutic Function Estrogen Chemical Name Estradiol phosphate polymer Common Name Polymeric ester of phosphoric acid and estradiol Structural Formula r... 

Common Name Zearalanol, tetrahydro F.E.S. (fermentation estrogenic substance) Structural Formula ... 

Diethylstilbestrol (DES) has estrogenic activity even though it is structurally unrelated to steroids. Once used as an additive in animal feed, DES has been implicated as a causative agent in several types of cancer. Show how DES can be drawn so that it is sterically similar to estradiol. 

The concept that different ligands play an active role in ER function is apparent at the biochemical level. In addition to competitive inhibition of estrogen binding, antiestrogens induce unique conformations/stiuctures of both ERa and ER 3. This provides a structural basis for the unique biological activities displayed by the different compounds [1]. 

Sex Steroid Receptors Androgen Receptor, Estrogen Receptors, Progesterone Receptor. Figure 1 Schematic structures of AR, ERa, ER(3, and PR. 

Gao H, Williams C, Labute P, Bajorath J. Binary quantitative structure-activity relationship (QSAR) analysis of estrogen receptor ligands. / Chem Inf Comput Sci 1999 39 164-8. 

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