- Microbiological hydroxylation of some epoxy steroids by the fungus Mucor plumbeus
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The preparation of epoxy steroids derived from testosterone, dehydroisoandrosterone and epiandrosterone using m-chloroperbenzoic acid and their biotransformation by the fungus Mucor plumbeus is described. The results reveal an effect of the epoxide on the biotransformation.
- Alfooty, Khalid. O.
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- Highly efficient epoxidation of unsaturated steroids using magnesium bis(monoperoxyphthalate) hexahydrate
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Fast generation of epoxides from the corresponding homoallylic and allylic steroidal olefins was developed by using magnesium bis(monoperoxyphthalate) hexahydrate (MMPP) as oxidant suspended in acetonitrile (CH3CN) at reflux temperature. The protocol involves the use of a safe readily available oxidant along with an easy work-up, which renders the process very efficient. Selective 4,5- and 5,6-epoxidations of steroids are reported. Among them, highly stereoselective epoxidation of Δ5-B-nor-cholestanes was achieved. Moreover, the method is chemoselective for the 5,6-position and can be applied to the epoxidation of ring-A enones.
- Carvalho, Jo?o F.S.,Silva, M. Manuel Cruz,Sá e Melo, M. Luisa
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- Chemoselective epoxidation of cholesterol derivatives on a surface-designed molecularly imprinted Ru-porphyrin catalyst
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A new molecularly imprinted Ru-porphyrin complex catalyst on a SiO2 support was designed, prepared, and characterized in a step-by-step manner for the C5C6 epoxidation of cholesterol derivatives. High chemoselectivity for the C5C6 epoxidation of cholesterol derivatives without protecting the 3-position OH group and other oxidizable functional groups was achieved on the molecularly imprinted catalyst.
- Muratsugu, Satoshi,Baba, Hiroshi,Tanimoto, Tatsuya,Sawaguchi, Kana,Ikemoto, Satoru,Tasaki, Masahiro,Terao, Yosuke,Tada, Mizuki
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- The Preparation and Dienone-Phenol Rearrangement of Androsta-2,5-diene-4,17-dione
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The preparation of androsta-2,5-diene-4,17-dione from dehydroisoandrosterone is described.Its dienone-phenol rearrangement, in the presence of hydrobromic acid and glacial acetic acid, affords 1-methyl-4-hydroxy-estra-1,3,5(10)-trien-17-one.
- Hanson, James R.,Raines, David,Knights, Steve G.
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- Poly(per)fluoroalkanesulfonyl fluoride promoted olefin epoxidation with 30% aqueous hydrogen peroxide
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Epoxidation of various electron rich olefins with a novel oxidation system of poly(per)fluoroalkanesulfonyl fluoride/hydrogen peroxide/base is reported.
- Yan, Zhaohua,Tian, Weisheng
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- AMINO DERIVATIVES OF ANDROSTANES AND ANDROSTENES AS MEDICAMENTS FOR CARDIOVASCULAR DISORDERS
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Compounds of formula (I) wherein: the groups are as defined in the description, are useful for the preparation of medicaments for the treatment of cardiovascular disorders, in particular heart failure and hypertension. The compounds are inhibitors of the enzymatic activity of the Na+, K+-ATPase. Said compounds are used for the preparation of a medicament for the treatment of a disease caused by the hypertensive effects of endogenous ouabain, such as renal failure progression in autosomal dominant polycystic renal disease (ADPKD), preeclamptic hypertension and proteinuria and renal failure progression in patients with adducin polymorphisms.
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Page/Page column 39-40
(2011/04/14)
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- AMINO DERIVATIVES OF ANDROSTANES AND ANDROSTENES AS MEDICAMENTS FOR CARDIOVASCULAR DISORDERS
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Compounds of formula (I) wherein:the groups are as defined in the description, are useful for the preparation of medicaments for the treatment of cardiovascular disorders, in particular heart failure and hypertension. The compounds are inhibitors of the enzymatic activity of the Na+,K+-ATPase. Said compounds are used for the preparation of a medicament for the treatment of a disease caused by the hypertensive effects of endogenous ouabain, such as renal failure progression in autosomal dominant polycystic renal disease (ADPKD), preeclamptic hypertension and proteinuria and renal failure progression in patients with adducin polymorphisms.
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Page/Page column 131
(2008/06/13)
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- AZAHETEROCYCLYL DERIVATIVES OF ANDROSTANES AND ANDROSTENES AS MEDICAMENTS FOR CARDIOVASCULAR DISORDERS
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Compounds of formula (I) wherein: the groups are as defined in the description, are useful for the preparation of medicaments for the treatment of cardiovascular disorders, in particular heart failure and hypertension. The compounds are inhibitors of the enzymatic activity of the Na+,K+-ATPase. They are useful for the preparation of a medicament for the treatment of a disease caused by the hypertensive effects of endogenous ouabain, such as renal failure progression in autosomal dominant polycystic renal disease (ADPKD), preeclamptic hypertension and proteinuria and renal failure progression in patients with adducin polymorphisms.
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Page/Page column 112-113
(2008/06/13)
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- Epoxidation and Reduction of DHEA, 1,4,6-Androstatrien-3-one and 4,6-Androstadien-3β,17β-diol
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Dehydroepiandrosterone (DHEA) reacted with m-chloroperoxybenzoic acid (m-CPBA) to form 3β-hydroxy-5α,6α-epoxyandrostan-17-one (1), but it did not react with 30 percent H2O2. 1,4,6-Androstatrien-3,17-dione (2) was obtained from DHEA and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone in dioxane. Compound 2 was reacted with 30 percent H2O2 and 5 percent NaOH in methanol to give 1α,2α-epoxy-4,6-androstadien-3,17-dione (3), which was stereoselectively reduced with NaBH4 to form 1α,2α-epoxy-4,6-androstadien-3β,17β-diol (7) and reacted with Li metal in absolute ethanol-tetrahydrofuran mixture to give 2-ethoxy-1,4,6-androstatrien-3,17-dione (8). Compound 2 was also epoxidized with m-CPBA in dichloromethane to afford 6α,7α-epoxy-1,4- androstadien-3,17-dione (4), which was reacted with NaBH4 to synthesize 6α,7α-epoxy-4-androsten-3β,17β-diol (9). Compound 4 was reduced with Li metal in absolute ethanol-tetrahydrofuran mixture to form 7β-ethoxy-6α-hydroxy-1,4-androstadien-3,17-dione (10). Compound 2 was reduced with NaBH4 in absolute ethanol to form 4,6-androstadien-3β,17β-diol (5), which was reacted with 30 percent H2O2 to give the original compound, but which reacted with m-CPBA to give 4β,5β-epoxy-6-androsten-3β,17β-diol (6).
- Ma, Eunsook,Kim, Eunjeong
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p. 794 - 804
(2007/10/03)
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- Highly selective lipase-mediated discrimination of diastereomeric 5,6-epoxysteroids
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Stereoisomerically pure 3β-hydroxy-5,6-epoxysteroids were obtained by combining selective chemical methods for α- and β-epoxidation of Δ5-unsaturated steroids with enzymatic stereoselective esterification of the 3β-hydroxyl group. 5β,6β-Epoxy-3β- hydroxysteroids were efficiently acylated by Novozym 435 and lipase AK, whereas 5α,6α-epoxy-3β-hydroxysteroids were good substrates for Candida rugosa lipase. Mild enzymatic deacylation of the 3β-acetoxy group in the presence of the epoxy functionality was also accomplished by C. rugosa lipase-mediated hydrolysis.
- Cruz Silva, M. Manuel,Riva, Sergio,Sa E Melo, M. Luisa
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p. 1173 - 1179
(2007/10/03)
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- Tetramethyldiamidophosphoric acid chloride mediated epoxide-diene conversion and steroidal aromatization
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The reaction of tetramethyldiamidophosphoric acid chloride with epoxides in the presence of a trace amount of water furnished 1,3-dienes in good yield. The conversion works with open chain and cyclic epoxides. A C-C bond cleavage reaction occurs if the epoxide contains a quaternary carbon. Application of this method to epoxy sterols afforded ring A aromatic steroids in good yield. The aromatization works via dienol-benzene rearrangements and is independent of the C-3 stereochemistry.
- Demir, Ayhan S
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p. 227 - 233
(2007/10/03)
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- Highly β-selective epoxidation of Δ5-unsaturated steroids catalyzed by ketones
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A general catalytic and environmentally friendly method for β-epoxidation of Δ5-unsaturated steroids has been developed, which uses ketones as the catalysts and Oxone as the terminal oxidant. A whole range of Δ5-unsaturated steroids, which bear different functional groups such as hydroxyl, carbonyl, acetyl, or ketal, as well as different side chains, were conveniently converted to the corresponding synthetically and biologically interesting 5β,5β-epoxides with excellent β-selectivities and high yields.
- Yang, Dan,Jiao, Guan-Sheng
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p. 3517 - 3521
(2007/10/03)
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- Preparation of Steroidal 5β,6β-Epoxides and their Oxidation by Chromium Trioxide
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Reaction of 3α-chloroandrost-5-en-17-one with m-chloroperbenzoic acid affords the 5β,6β-epoxide.This is accompained by some Baeyer-Villiger oxidation at C-17.The 3α-chlorine atom can be removed by hydrogenolysis with tributyltin hydride.Although the unsubstituted 5β,6β-epoxide is oxidized by chromium trioxide to the 5α-hydroxy 6-ketone, the 3α-chloro 5β,6β-epoxide is unreactive.
- Hanson, James R.,Truneh, Almaz
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p. 2001 - 2004
(2007/10/02)
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- Microbiological Transformations. Part 3. The Oxidation of Androstene Derivatives with the Fungus Cunninghamella elegans
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The products obtained from the incubation of some Δ4- and Δ5-androstene derivatives with Cunninghamella elegans are largely those arising from allylic oxidation or epoxidation of the double bond, but some 9-, 12-, 14-, and 16-hydroxylation also occurs.
- Crabb, Trevor A.,Dawson, Philip J.,Williams, Roger O.
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p. 2535 - 2541
(2007/10/02)
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