- Synthesis and some reactions of 6-bromoandrogens: Potential affinity ligand and inactivation of estrogen synthetase
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The synthesis of epimeric 6-bromo-4-androstene-3,17-dione (1a and 1b), 6-bromotestosterone (2a and 2b) and its acetate (3a and 3b), and 6-bromo-16α-acetoxy-4-androstene-3,17-dione (5a and 5b), and 6β-bromo-16α-hydroxy-4-androstene-3,17-dione (4) is described. The interconversions among compounds 1, 2, and 3 are also studied. The 6β-isomer (1b, 2b, and 3b) was epimerized to the 6α-isomer (1a, 2a and 3a) in carbon tetrachloride or chloroform-methanol (9:1) and the 6α-isomer was isolated by fractional crystallization from the epimeric mixture. 6α-Bromo isomer 1a was also epimerized back to 6β-bromo isomer 1b in chloroform-methanol (9:1). Two polymorphic forms of 6β-bromotestosterone acetate (3b) were isolated (mp. 114-117° and 138-141°). The 6β-bromo isomers were found to be unstable in methanol and decomposed to give 5α-androstane-3,6-dione derivative (6). The results of irreversible inactivation of human placental androgen aromatase with some of these 6-bromoandrogens are discussed.
- Numazawa,Osawa
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- 6-Chloro- and 6-bromo-substituted steroids in the Suzuki-Miyaura cross-coupling reaction. A convenient route to potential aromatase inhibitors
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Chlorine at an sp2-carbon in steroids has been shown to be reactive in Suzuki-Miyaura cross-coupling reactions with either Ni or Pd catalysts. The coupling of analogous 6-bromo derivatives has also been demonstrated to be applicable to a wider scope of substrates. The Suzuki-Miyaura arylation of 6-bromo-Δ3,5-steroid enol ethers with subsequent hydrolysis is a useful route to 6-arylated steroids bearing aryl at a saturated carbon. Georg Thieme Verlag Stuttgart.
- Lukashev, Nikolay V.,Latyshev, Gennadij V.,Donez, Pavel A.,Skryabin, George A.,Beletskaya, Irina P.
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- Convenient method for the functionalization of the 4- and 6-positions of the androgen skeleton
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The preparation and reactivity of steroidal vinyldiazo compounds is reported, providing a convenient, substituent tolerant, chemo- and stereoselective entry into 4- and 6-substituted androgen analogues from a common precursor. Under dirhodium catalysis, O-H insertion occurs at the carbenoid site, leading to 4-substituted steroids, but under silver catalysis, O-H insertion occurs at the vinylogous position, leading to 6-substituted steroids.
- Morton, Daniel,Dick, Allison R.,Ghosh, Debashis,Davies, Huw M. L.
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supporting information; experimental part
p. 5838 - 5840
(2012/07/14)
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- SUBSTITUTED ANDROST-4-ENE DIONES
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The disclosure relates to novel C4 and C6 substituted androst-4-ene diones as well as andros-1,4-diene diones and derivatives thereof, their process of preparation, pharmaceutical compounds containing them, and the use of said compounds for the treatment of hormone-related disorders in mammals. This includes hormone-dependent cancers, particularly those caused by elevated levels of estrogen and its intermediates. These compounds can also be used in the treatment of other hormone-related disorders, inluding benign prostatic hyperplasia, cardiovascular disease, and neurodegenerative disorders.
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Page/Page column 63
(2011/10/31)
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- Aromatase Inhibitors. Synthesis and Biological Activity of Androstenedione Derivatives
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The synthesis and biological evaluation of androstenedione derivatives as inhibitors of estrogen biosynthesis are described.The results show that 4-hydroxy analogues are among the most potent in vitro inhibitors of the series.Esterification of the 4-hydroxy steroids generally reduced activity.Further conjugation of the 3-keto 4-ene system to give 4-hydroxy-4,6-androstadiene-3,17-dione caused more rapid inactivation of aromatase in rat ovarian microsomes than 4-hydroxyandrostenedione.Some compounds exhibited differences in activity when tested for inhibition of human placental microsomes vs. rat ovarian microsomes.The 4-hydroxyandrostenedione derivatives and their nonbulky esters were generally more potent in vitro and in vivo inhibitors than other substituted steroids in the series.Several of the synthesized compounds markedly reduce (50-81percent) estrogen levels in rats on proestrus and/or had antifertility action.To date, none of the compounds surpassed the in vivo inhibitory action of 4-hydroxy-4-androstene-3,17-dione or its 4-acetate derivative.
- Marsh, David A.,Brodie, Harry J.,Garrett, Wesley,Tsai-Morris, Chon-Hwa,Brodie, Angela M. H.
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p. 788 - 795
(2007/10/02)
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