1229-12-5Relevant academic research and scientific papers
X-ray and deuterium labeling studies on the abnormal ring cleavages of a 5β-epoxide precursor of formestane
Tavares Da Silva, Elisiario J,Roleira, Fernanda M.F,Sa E Melo, M.Luisa,Campos Neves, Andre S,Paixao, Jose A,De Almeida, Maria J,Silva, Manuela R,Andrade, Lourdes C.R
, p. 311 - 319 (2002)
A new convergent synthesis of the antitumor steroid formestane (4-OHA) 5 has been performed from the easily available epimeric mixture of 5α- and 5β-androst-3-en-17-one 1a and 1b in order to attempt a yield improvement. A two-step oxidative route followed by base-catalyzed isomerization was applied to the 5α- and 5β-epimers 1a and 1b, either as a mixture or separately, leading to the title compound 5. From epimer 1a an efficient process was attained to prepare the desired aromatase inhibitor formestane. Epimer 1b led to the formation of the same compound 5. Additionally, 1b have also been converted in 5β-hydroxyandrostane-3,17-dione 12 and androst-4-ene-3,17-dione 13, revealing an unexpected reactivity of the 3β,4β-epoxy-5β-androstan-17-one intermediate 6 formed from 1b during the first oxidative step with performic acid. Cleavage of the epoxide 6 led to the trans-diaxial and the trans-diequatorial vic-diols 7 and 8 and to the 1,3-diol 9. The formation of the abnormal products 8 and 9 were investigated through X-ray and deuterium labeling studies. Diol 8 was formed through a trans-diequatorial epoxide ring opening and the 1,3-diol 9 was formed through an intramolecular rearrangement involving a 1,2-hydride shift. All the vic-diols 3, 7 and 8 formed, proved to be good precursors for the synthesis of the target compound 5. Copyright
Molecular cloning and heterologous expression of progesterone 5β-reductase from Digitalis lanata Ehrh.
Herl, Vanessa,Fischer, Gabriele,Müller-Uri, Frieder,Kreis, Wolfgang
, p. 225 - 231 (2006)
A full-length cDNA clone that encodes progesterone 5β-reductase (5β-POR) was isolated from Digitalis lanata leaves. The reading frame of the 5β-POR gene is 1170 nucleotides corresponding to 389 amino acids. For expression, a Sph1/Sal1 5β-POR fragment was cloned into the pQE vector and was transformed into Escherichia coli strain M15[pREP4]. The recombinant gene was functionally expressed and the recombinant enzyme was characterized. The Km and vmax values for the putative natural substrate progesterone were calculated to be 0.120 mM and 45 nkat mg-1 protein, respectively. Only 5β-pregnane-3,20-dione but not its α-isomer was formed when progesterone was used as the substrate. Kinetic constants for cortisol, cortexone, 4-androstene-3,17-dione and NADPH were also determined. The molecular organization of the 5β-POR gene in D. lanata was determined by Southern blot analysis. The 5β-POR is highly conserved within the genus Digitalis and the respective genes and proteins share considerable homology to putative progesterone reductases from other plant species.
Platinum supported on TiO2 as a new selective catalyst on heterogeneous hydrogenation of α,β-unsaturated oxosteroids
Nunes, Rui M.D.,MacHado, Bruno F.,Pereira, Mariette M.,Moreno, Maria José S.M.,Faria, Joaquim L.
, p. 1 - 5 (2010)
This paper describes the photochemical deposition of platinum onto TiO 2 surface and the full characterization of the catalysts using BET, XPS and TEM techniques. The 1 and 3 wt. % Pt/TiO2 catalysts reveal high activity with 70% and 96% of α-diastereoselectivity in the hydrogenation of the carbon-carbon double bond of the α,β-unsaturated oxosteroids 4-androstene-3,17-dione, and 3β-acetoxypregna-5,16-dien-20- one, respectively. Using higher temperature and pressure, the catalysts promote the further reduction of C-3 carbonyl group. Catalyst recovering and recycling is easily achieved with no appreciable lost of catalytic activity after five subsequent runs.
Synthesis and biological evaluation of steroidal derivatives bearing a small ring as vitamin D receptor agonists
Arichi, Norihito,Fujiwara, Shinichi,Ishizawa, Michiyasu,Makishima, Makoto,Hua, Duy H.,Yamada, Ken-ichi,Yamaoka, Yousuke,Takasu, Kiyosei
, p. 3408 - 3411 (2017)
A novel series of 3-ketolithocholic acid derivatives as well as estrone derivatives bearing a small ring for the conformational fixation of the side chain were synthesized by using a catalytic [2+2] cycloaddition and a ring-contraction rearrangement. The steroidal derivatives were evaluated for transcriptional activation of vitamin D receptor by luciferase reporter assays. Among them, two estrone derivatives showed a higher efficacy of the transactivation of vitamin D receptor than 3-ketolithocholic acid, and the small ring moieties were found to be important for the efficacy.
REDUCTIONS MICROBIOLOGIQUES STEREOSELECTIVES DES Δ-4 CETO-3 STEROIDES
Fauve, A.,Kergomard, A.
, p. 899 - 901 (1981)
In anaerobic conditions the reduction of Δ-4 3-keto steroids by Clostridium paraputrificum leads either to the 3-keto 5β compounds or to the corresponding 3α-hydroxytetrahydro-5β derivatives.This stereospecific bioconversion of αβ-unsaturated 3-keto steroids is shown to be directed by the substrate concentration.The conversion of Δ-4 cholestenone to coprostanone or coprostanol is not observed.
5β-Androstan-3,17-dione
Anthony, Addlagatta,Jaskolski, Mariusz,Nangia, Ashwini,Desiraju, Gautam R.
, p. 1898 - 1900 (1998)
The title compound, C19H28O2, has the 5β configuration and a bowing angle of 71.76(5)° at the A/B ring junction. The crystal structure is stabilized by weak intermolecular C-H...O and van der Waals interactions.
Synthesis of Cardiotonic Steroids Oleandrigenin and Rhodexin B
Fejedelem, Zachary,Carney, Nolan,Nagorny, Pavel
, p. 10249 - 10262 (2021/07/31)
This article describes a concise synthesis of cardiotonic steroids oleandrigenin (7) and its subsequent elaboration into the natural product rhodexin B (2) from the readily available intermediate (8) that could be derived from the commercially available steroids testosterone or DHEA via three-step sequences. These studies feature an expedient installation of the β16-oxidation based on β14-hydroxyl-directed epoxidation and subsequent epoxide rearrangement. The following singlet oxygen oxidation of the C17 furan moiety provides access to oleandrigenin (7) in 12 steps (LLS) and a 3.1% overall yield from 8. The synthetic oleandrigenin (7) was successfully glycosylated with l-rhamnopyranoside-based donor 28 using a Pd(II)-catalyst, and the subsequent deprotection under acidic conditions provided cytotoxic natural product rhodexin B (2) in a 66% yield (two steps).
Unified Total Synthesis of Five Bufadienolides
Hagiwara, Koichi,Inoue, Masayuki,Itoh, Hiroaki,Shimizu, Shinsuke
supporting information, (2020/11/13)
We report a unified total synthesis of five bufadienolides: bufalin (1), bufogenin B (2), bufotalin (3), vulgarobufotoxin (4), and 3-(N-succinyl argininyl) bufotalin (5). After the steroidal ABCD ring 8 was produced, the D ring was cross-coupled with a 2-pyrone moiety and stereoselectively epoxidized to generate 6. TMSOTf promoted a stereospecific 1,2-hydride shift from 6 to establish the β-oriented 2-pyrone of 19. Functional group manipulations from 19 furnished 1-5, which potently inhibited cancer cell growth.
Steroid compound, application and preparation method thereof
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Paragraph 0225-0226; 0239, (2020/07/24)
The invention relates to a steroid compound, an application and a preparation method thereof. The compounds are expected to be capable of effectively treating neuropsychiatric diseases, and have goodactive efficacy, pharmacokinetic (PK) performance, oral
New photocatalytic fixed-point deuteration method for carbon-carbon unsaturated bonds
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Paragraph 0055; 0057; 0058; 0062, (2019/01/21)
The invention relates to a new photocatalytic fixed-point deuteration method for carbon-carbon unsaturated bonds. The method is characterized in that an olefin or alkyne compound and a deuterium source undergoes a deuteration reaction under the catalysis of a light source and a photocatalyst to obtain a deuterated product, wherein the deuterium source is deuterated water, deuterated alcohol or deuterated acid, and the reaction temperature is between room temperature and 80 DEG C. The fixed-point deuteration reaction of the olefin or alkyne compound is realized under the photocatalysis action of the photocatalyst with environmentally-friendly and cheap deuterated water or a deuteration reagent as a deuterium source to substitute deuterium gas. Compared with traditional deuteration reactions, the method has a higher selectivity, milder reaction conditions and higher economical suitability, and is suitable for large-scale deuterated chemical substance production.
