17-hydroxysteroids

Measurements of levels of 17α-OHP are useful in the evaluation of patients with suspected congenital adrenal hyperplasia as the typical enzymes that are defective, namely 21-hydroxylase and 11β-hydroxylase , lead to a build-up of 17α-OHP. In contrast, the rare patient with 17α-hydroxylase deficiency will have very low or undetectable levels of 17α-OHP. 17α-OHP levels can also be used to measure contribution of progestational activity of the corpus luteum during pregnancy as progesterone but not 17α-OHP is also contributed by the placenta .

Allylic bromination (. with N-bromosuccinimide (NBS)) of 17β-acetoxyandrosta-1,4-dien-3-one 8 followed by treatment with zinc affords the non-conjugated enone 9. 1,4-Alkylation with lithiodimethyl cuprate provides the 1α-methyl ketone 10a. At this stage the 10a may be converted to a methylene by Wolff-Kishner reduction or the Huang Minlon modification thereof. These vigorous reaction conditions result in hydrolysis of the resulting carbon-17 acetate thereby yielding the hydroxy desoxy derivative, 17β-hydroxy-1α-methylandrost-5-ene (3b). Both 10a and its desoxy derivative can be converted via standard reactions, ., hydrolysis of the 17-acetate with sodium carbonate and methanol followed by chromium trioxide oxidation of the resulting 17-alcohol to the carbon-17 ketone. Selective reduction of the carbon-3 ketone, 3,17-diketone 3c using sodium borohydride pyridine (pyr) yields 1α-methyl dehydroepiandrosterone 3a. CARBON-2-ALKYLATIONS

Allylic bromination (. with N-bromosuccinimide (NBS)) of 17β-acetoxyandrosta-1,4-dien-3-one 8 followed by treatment with zinc affords the non-conjugated enone 9. 1,4-Alkylation with lithiodimethyl cuprate provides the 1α-methyl ketone 10a. At this stage the 10a may be converted to a methylene by Wolff-Kishner reduction or the Huang Minlon modification thereof. These vigorous reaction conditions result in hydrolysis of the resulting carbon-17 acetate thereby yielding the hydroxy desoxy derivative, 17β-hydroxy-1α-methylandrost-5-ene (3b). Both 10a and its desoxy derivative can be converted via standard reactions, ., hydrolysis of the 17-acetate with sodium carbonate and methanol followed by chromium trioxide oxidation of the resulting 17-alcohol to the carbon-17 ketone. Selective reduction of the carbon-3 ketone, 3,17-diketone 3c using sodium borohydride pyridine (pyr) yields 1α-methyl dehydroepiandrosterone 3a.

17-hydroxysteroids

17-hydroxysteroids

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