Estradiol (known as α-Estradiol or 17 α-Estradiol) is a biologically active estrogen in human breast cancer cells in tissue culture. 17-Εstradiol and its selective receptor, ER-X, are not part of a classical hormone/receptor endocrine system but of a system with important autocrine/paracrine functions in the developing and adult brain. 17-Estradiol may have enormous implications for hormone replacement strategies at the menopause and in the treatment of such neurodegenerative disorders as Alzheimer’s disease and ischemic stroke.
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ChEBI: An estradiol that is estra-1,3,5(10)-triene substituted by hydroxy groups at positions 3 and 17 (the 17alpha stereoisomer).
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Endogenous estrogen receptor ligand (K i values are 0.2 and 1.2 nM for ER α and ER β receptors respectively).
Purification Methods
17-Estradiol recrystallises from aqueous EtOH (80%) as the hemihydrate and differs from the -anomer (below) by not precipitating with digitonin in 80% aqueous EtOH. The diacetate [1474-52-8] crystallises from aqueous EtOH in needles with m 139-140o. The 3-benzoate crystallises in three forms m 158o, 153o and 63o.
