- Pd nanoparticles as catalysts for green and sustainable oxidation of functionalized alcohols in aqueous media
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The previously described catalyst system for the aerobic oxidation of alcohols, comprising palladium(II) acetate in combination with neocuproine in a 1:1 mixture of water and a water-miscible cosolvent such as ethylene carbonate or dimethylsulfoxide, was shown to involve palladium nanoparticles as the active catalyst. The latter are formed in situ or can be preformed by reduction of the palladium-neocuproine complex with hydrogen and they are stabilized by both the neocuproine ligand and the cosolvent. This catalyst system was successfully used for the selective aerobic oxidation of the steroidal secondary alcohols, nandrolone and 5α-pregnan-3α-ol-20-one, to the corresponding ketones.
- Mifsud, Maria,Parkhomenko, Ksenia V.,Arends, Isabel W.C.E.,Sheldon, Roger A.
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Read Online
- Hydrogenation reaction method
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The invention relates to a hydrogenation reaction method, and belongs to the technical field of organic synthesis. The hydrogenation reaction method provided by the invention comprises the following steps: carrying out a hydrogen transfer reaction on a hydrogen acceptor compound, pinacol borane and a catalyst in a solvent in the presence of proton hydrogen, so that the hydrogen acceptor compound is subjected to a hydrogenation reaction; the catalyst is one or more than two of a palladium catalyst, an iridium catalyst and a rhodium catalyst; the hydrogen acceptor compound comprises one or morethan two functional groups of carbon-carbon double bonds, carbon-carbon triple bonds, carbon-oxygen double bonds, carbon-nitrogen double bonds, nitrogen-nitrogen double bonds, nitryl, carbon-nitrogentriple bonds and epoxy. The method is mild in reaction condition, easy to operate, high in yield, short in reaction time, wide in substrate application range, suitable for carbon-carbon double bonds,carbon-carbon triple bonds, carbon-oxygen double bonds, carbon-nitrogen double bonds, nitrogen-nitrogen double bonds, nitryl, carbon-nitrogen triple bonds and epoxy functional groups, good in selectivity and high in reaction specificity.
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Paragraph 0034; 0181-0184
(2020/05/14)
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- Generalized Chemoselective Transfer Hydrogenation/Hydrodeuteration
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A generalized, simple and efficient transfer hydrogenation of unsaturated bonds has been developed using HBPin and various proton reagents as hydrogen sources. The substrates, including alkenes, alkynes, aromatic heterocycles, aldehydes, ketones, imines, azo, nitro, epoxy and nitrile compounds, are all applied to this catalytic system. Various groups, which cannot survive under the Pd/C/H2 combination, are tolerated. The activity of the reactants was studied and the trends are as follows: styrene'diphenylmethanimine'benzaldehyde'azobenzene'nitrobenzene'quinoline'acetophenone'benzonitrile. Substrates bearing two or more different unsaturated bonds were also investigated and transfer hydrogenation occurred with excellent chemoselectivity. Nano-palladium catalyst in situ generated from Pd(OAc)2 and HBPin extremely improved the TH efficiency. Furthermore, chemoselective anti-Markovnikov hydrodeuteration of terminal aromatic olefins was achieved using D2O and HBPin via in situ HD generation and discrimination. (Figure presented.).
- Wang, Yong,Cao, Xinyi,Zhao, Leyao,Pi, Chao,Ji, Jingfei,Cui, Xiuling,Wu, Yangjie
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supporting information
p. 4119 - 4129
(2020/08/10)
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- NEUROSTEROID COMPOUNDS AND METHODS FOR THEIR PREPARATION AND USE IN TREATING CENTRAL NERVOUS SYSTEM DISORDERS
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Described herein is the chemical structure of neurosteroid derivative compounds, methods of synthesizing the derivatives, and their uses in treating disorders, including those of the central nervous system. These compounds are readily synthesized and have improved pharmaceutical properties, including water solubility, compared to known neurosteroids.
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- COMPOSITIONS AND METHODS FOR TREATING CNS DISORDERS
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Described herein are neuroactive steroids of the Formula (I): or a pharmaceutically acceptable salt thereof; wherein (II), A, R1, R2, R3a, R4a, R4b, R5, R7a, and R7b are as defined herein. Such compounds are envisioned, in certain embodiments, to behave as GABA modulators. The present invention also provides pharmaceutical compositions comprising a compound of the present invention and methods of use and treatment, e.g., such for inducing sedation and/or anesthesia.
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- Characterization of hamster NAD+-dependent 3(17)β-hydroxysteroid dehydrogenase belonging to the aldo-keto reductase 1C subfamily
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The cDNAs for morphine 6-dehydrogenase (AKR1C34) and its homologous aldo-keto reductase (AKR1C35) were cloned from golden hamster liver, and their enzymatic properties and tissue distribution were compared. AKR1C34 and AKR1C35 similarly oxidized various xenobiotic alicyclic alcohols using NAD+, but differed in their substrate specificity for hydroxysteroids and inhibitor sensitivity. While AKR1C34 showed 3α/17β/20α-hydroxysteroid dehydrogenase activities, AKR1C35 efficiently oxidized various 3β- and 17β-hydroxysteroids, including biologically active 3β-hydroxy-5α/β-dihydro-C19/C21-steroids, dehydroepiandrosterone and 17β-estradiol. AKR1C35 also differed from AKR1C34 in its high sensitivity to flavonoids, which inhibited competitively with respect to 17β-estradiol (Ki 0.11-0.69 μM). The mRNA for AKR1C35 was expressed liver-specific in male hamsters and ubiquitously in female hamsters, whereas the expression of the mRNA for AKR1C34 displayed opposite sexual dimorphism. Because AKR1C35 is the first 3(17)β-hydroxysteroid dehydrogenase in the AKR superfamily, we also investigated the molecular determinants for the 3β-hydroxysteroid dehydrogenase activity by replacement of Val54 and Cys310 in AKR1C35 with the corresponding residues in AKR1C34, Ala and Phe, respectively. The mutation of Val54Ala, but not Cys310Phe, significantly impaired this activity, suggesting that Val54 plays a critical role in recognition of the steroidal substrate.
- Endo, Satoshi,Noda, Misato,Ikari, Akira,Tatematsu, Kenjiro,El-Kabbani, Ossama,Hara, Akira,Kitade, Yukio,Matsunaga, Toshiyuki
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p. 425 - 434
(2015/11/27)
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- Tetrabutylammonium prolinate-based ionic liquids: A combined asymmetric catalysis, antimicrobial toxicity and biodegradation assessment
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Chiral ionic liquids (CILs) tetrabutylammonium-(S)-prolinate, tetrabutylammonium-(R)-prolinate and tetrabutylammonium trans-4-hydroxy-(S)- prolinate were investigated as chiral additives in the Pd-catalyzed enantioselective hydrogenation of α,β-unsaturated ketones. These CILs were easily prepared in one step from the aminoacid and tetrabutylammonium hydroxide and characterized (NMR, IR, optical rotation, elemental analysis, DSC, viscosity, decomposition temperature). The research strategy was to assess the antimicrobial toxicity (>20 strains) and biodegradability (OECD 301D) of the CILs at the same time as undertaking the asymmetric catalysis study. The Pd-catalyzed enantioselective hydrogenation of the carbon-carbon double bond of α,β-unsaturated ketones under mild conditions (room temperature, 1 atm of H2) in different solvents with CILs present. The best results were obtained in i-PrOH after 18 hours of reaction with a i-PrOH/IL ratio of 5. While all three CILs have low antimicrobial toxicity to a wide range of bacteria and fungi, tetrabutylammonium-(S)-prolinate, tetrabutylammonium-(R)-prolinate and tetrabutylammonium trans-4-hydroxy-(S)-prolinate did not pass the Closed Bottle biodegradation test.
- Ferlin, Nadege,Courty, Matthieu,Van Nhien, Albert Nguyen,Gatard, Sylvain,Pour, Milan,Quilty, Brid,Ghavre, Mukund,Haiss, Annette,Kuemmerer, Klaus,Gathergood, Nicholas,Bouquillon, Sandrine
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p. 26241 - 26251
(2013/12/04)
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- Biotransformation of testosterone and progesterone by Penicillium digitatum MRC 500787
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The biotransformation of testosterone and progesterone by Penicillium digitatum MRC 500787 for 5 days is described. The biotransformation of testosterone afforded 5α-androstane-3,17-dione, 3α-hydroxy-5α- androstan-17-one, 3β-liydroxy-5α-androstan-17-one and androst-4-ene-3,17-dione. The biotransformation of progesterone afforded 5α-pregnane- 3,20-dione.
- Yildirim, Kudret,Gulsan, Fatih,Kupcu, Ilknur
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experimental part
p. 675 - 683
(2011/08/03)
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- Aspects of the progesterone response in Hortaea werneckii: Steroid detoxification, protein induction and remodelling of the cell wall
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Progesterone in sublethal concentrations temporarily inhibits growth of Hortaea werneckii. This study investigates some of the compensatory mechanisms which are activated in the presence of progesterone and are most probably contributing to escape from growth inhibition. These mechanisms lead on the one hand to progesterone biotransformation/detoxification but, on the other, are suggested to increase the resistance of H. werneckii to the steroid. Biotransformation can detoxify progesterone efficiently in the early logarithmic phase, with mostly inducible steroid transforming enzymes, while progesterone biotransformation/detoxification in the late logarithmic and stationary phases of growth is not very efficient. The relative contribution of constitutive steroid transforming enzymes to progesterone biotransformation is increased in these latter phases of growth. In the presence of progesterone, activation of the cell wall integrity pathway is suggested by the overexpression of Pck2 which was detected in the stationary as well as the logarithmic phase of growth of the yeast. Progesterone treated H. werneckii cells were found to be more resistant to cell lysis than mock treated cells, indicating for the first time changes in the yeast cell wall as a result of treatment with progesterone.
- Krizancic Bombek, Lidija,Lapornik, Ajda,Ukmar, Marjeta,Matis, Maja,Cresnar, Bronislava,Katalinic, Jasna Peter,Zakelj-Mavric, Marija
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experimental part
p. 1465 - 1474
(2009/04/06)
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- Δ5-3β-hydroxysteroid dehydrogenase (3βHSD) from Digitalis lanata. Heterologous expression and characterisation of the recombinant enzyme
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During the biosynthesis of cardiac glycosides, Δ5-3β- hydroxysteroid dehydrogenase (3βHSD, EC 1.1.1.51) converts pregnenolone (5-pregnen-3β-ol-20-one) to isoprogesterone (5-pregnene-3,20-dione). A 3βHSD gene was isolated from leaves of Digitalis lanata. It consisted of 870 nucleotides containing a 90 nucleotide long intron. A full-length cDNA clone that encodes 3βHSD was isolated by RT-PCR from the same source. A Sph I/Kpn I 3βHSD cDNA was cloned into the pQE30 vector and then transferred into E. coli strain M15[pREP4]. 3βHSD cDNA was functionally expressed as a His-tagged fusion protein (pQ3βHSD) composed of 273 amino acids (calculated molecular mass 28,561 Da). PQ3βHSD was purified by metal chelate affinity chromatography on Ni-NTA. Pregnenolone and other 3β-hydroxypregnanes but not cholesterol were 3β-oxidised by pQ3βHSD when NAD was used as the co-substrate. Testosterone (4-androsten-17β-ol-3-one) was converted to 4-androstene-3,17-dione indicating that the pQ3βHSD has also 17β-dehydrogenase activity. pQ3βHSD was able to reduce 3-keto steroids to their corresponding 3β-hydroxy derivatives when NADH was used as the co-substrate. For comparison, 3βHSD genes were isolated and sequenced from another 6 species of the genus Digitalis. Gene structure and the deduced 3βHSD proteins share a high degree of similarity. Georg Thieme Verlag KG Stuttgart.
- Herl, Vanessa,Frankenstein, Joerdis,Meitinger, Nadine,Mueller-Uri, Frieder,Kreis, Wolfgang
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p. 704 - 710
(2008/03/12)
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- Synthesis of 3α-hydroxy-21-(1′-imidazolyl)-3β-methoxyl- methyl-5α-pregnan-20-one via lithium imidazole with 17α- acetylbromopregnanone
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The synthesis of biologically active 3α-hydroxyl-21-(1′- imidazolyl)-3β-methoxymethyl-5α-pregnan-20-one (11) was accomplished in six steps. The key steps were the improvement of stereoselectivity for acetyl isomers in C-17 and the introduction of imidazole into the core structure by use of lithium imidazole. This latter key step provided the desired product 11 in 82% yield without the formation of 1,3-disubstituted imidazolium salt as impurity, which is generally observed in traditional method.
- Wong, Fung Fuh,Chen, Chun-Yen,Chen, Tse-Hsin,Huang, Jiann-Jyh,Fang, Hsiao-Ping,Yeh, Mou-Yung
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- A new pregnane derivative from the Indian ocean gorgonian Subergorgia suberosa (Pallas)
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3, 3-Dimethoxy-5α-pregnan-20-one 1, a new compound, has been isolated from the gorgonian S. suberosa.
- Subrahmanyam,Ratna Kumar,Damodar Reddy
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p. 219 - 220
(2007/10/03)
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- Deoximation of oximes to carbonyl compounds through in situ generation of nitrosyl chloride
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Oximes are effectively deoximated to regenerate the carbonyl compounds by a system comprising NaNO2 and acetyl chloride at room temperature.
- Goswami,Chowdhury
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p. 157 - 158
(2007/10/03)
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- Steroid transformations with Exophiala jeanselmei var. lecanii-corni and Ceratocystis paradoxa
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The fungi Exophiala jeanselmei var. lecanii-corni [IMI (International Mycological Institute) 312989, UAMH (University of Alberta Microfungus Collection and Herbarium) 8783] and Ceratocystis paradoxa (IMI 374529, UAMH 8784) have been examined for their potential in steroid biotransformation. The study has determined that E. jeanselmei var. lecanii-corni effected overall anti-Markovnikov hydration on dehydroisoandrosterone, and side-chain degradation on a variety of pregnanes. Both ascomycetes were found to carry out redox reactions of alcohols and ketones as well as 1,4 reduction of α,β-unsaturated carbonyl systems.
- Porter, Roy B.R.,Gallimore, Winklet A.,Reese, Paul B.
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p. 770 - 779
(2007/10/03)
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- Biotransformations of progesterone by Chlorella spp.
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Thirty-eight strains of Chlorella spp. were used as bioreactors on progesterone. Fourteen strains were ineffective whilst the others biotransformed the substrate. The observed bioreactions for progesterone were the hydroxylation, the reduction and the side-chain degradation. The kinds of biotransformation seem to fit the actual classification of the strains.
- Pollio, Antonino,Pinto, Gabriele,Della Greca, Marina,Fiorentino, Antonio,Previtera, Lucio
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p. 685 - 688
(2007/10/03)
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- Sodium-retaining activity of some natural and synthetic 21-deoxysteroids
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The effect of progesterone and six other C21 -deoxysteroids on renal sodium retention by male adrenaleotomized rats was compared with the effect exerted by the natural corticoids aldosterone, 11-deoxycorticosterone, and corticosterone. Steroids were active in the following order: aldosterone > 11,19-oxidoprogesterone > 5αH-3,20-pregnanedione ≥ 5βH-3,20-pregnanedione > progesterone = 11-ketoprogesterone > 6,19-oxidoprogesterone = 11-keto- 6,19-oxidoprogesterone ≥ corticosterone. All C21-deoxysteroids, except 11,19-oxidoprogesterone, exhibited parabolic log dose-response functions, indicating an effect that opposes renal sodium retention at high doses. 11,19-Oxidoprogesterone and the natural corticoids exhibited normal, exponential, log dose-response curves. Diverse geometric parameters related to molecular planarity were calculated and their correlation with biopharmacological properties was attempted. The best linear regression was obtained for correlation of the concavity of log dose-response parabolas (second-order coefficients) of C21-deoxysteroids with the C3=O/ring D angle of these molecules. A good linear regression could also be obtained for correlation of the affinity of C21-deoxysteroids, except 11,19- oxidoprogesterone, for purified type I mineralocorticoid receptors with those angles. The latter correlation deteriorated upon incorporation of the affinity data for the three natural corticoids, due to similar affinities of these hormones for type I mineralocorticoid receptors, but could be restored when the binding data for the unpurified, corticosterone-binding globulin- containing stage of the receptors were considered. In vivo binding data followed the same trend as that for unpurified receptors.
- Burton,Galigniana,De Lavallaz,Brachet-Cota,Sproviero,Ghini,Lantos,Damasco
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p. 535 - 543
(2007/10/03)
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- Biotransformation of corticosteroids by Penicillium decumbens ATCC 10436
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The biotransformation of a series of corticosteroids by the fungus Penicillium decumbens ATCC 10436 has been investigated. Conversion to the corresponding 5α-dihydroxteroid was observed for all the Δ4-3-ketosteroids studied with the exception of deoxycorticosterone, which was converted to a Δ14-diene. Deoxycorticosterone acetate was, however, converted to a 5α- dihydro product concomitant with ester hydrolysis. Other substrates carrying a C-21 acetoxy group were also hydrolyzed to the alcohol. In two cases (resulting from deoxycorticosterone acetate and 11-deoxycortisone) the 5α- 3-keto-product was further reduced to the 3β-alcohol. No reduction of δ14-dienes was observed.
- Holland, Herbert L.
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p. 646 - 649
(2007/10/02)
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- Direct transformation of steroidal ethers into ketones by dimethyldioxirane
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Treatment of the methyl- and benzyl ethers of 3-hydroxy steroids with a solution of dimethyldioxirane resulted in the formation of the corresponding ketones in high yield.
- Van Heerden,Dixon,Holzapfel
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p. 7399 - 7402
(2007/10/02)
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- Functionalisation of Saturated Hydrocarbons. Part 6. Selective Oxidation of Steroids and Related Compounds
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The oxidation of a series of steroids by the Gif system gives, almost without exception, the 20-ketone as major isolated product.The side-chain cleavage is made more selective by modification of rings A or B.The oxidation of oleana-1,12-diene-3,11-dione has also been studied and the two principal products have been identified.
- Barton, Derek H. R.,Boivin, Jean,Hill, Christopher H.
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p. 1797 - 1804
(2007/10/02)
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- STUDY OF THE DIRECT EFFECT OF LHRH AGONIST ON TESTICULAR 17-HYDROXYLASE AND 5α-REDUCTASE ACTIVITIES IN NON-HYPOPHYSECTOMIZED ADULT RATS TREATED WITH AN ANTI-LUTEINIZING HORMONE SERUM
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In order to study both direct and pituitary-mediated mechanisms of action of the LHRH analogue 6, des-Gly-NH210>LHRH ethylamide upon testicular steroidogenesis in adult rat, we compared the effects of the agonist when administered alone or concomitantly with an anti-LH serum to non-hypophysectomized rats.Testicular steroid contents and in vitro progesterone and testosterone metabolism were determined.Anti-LH serum administration was able to prevent 5α-reductase stimulation by the agonistic peptide, but not the inhibition of 17-hydroxylase activity.These data suggest that modulation of 17-hydroxylase involves both direct and pituitary-mediated processes, while 5α-reductase stimulation is mainly if not only due to a pituitary-mediated mechanism.
- Carmichael, Rejean,Belanger, Alain
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- Stereochemistry of the Palladium-catalyzed Hydrogenation of 3-Oxo-4-ene Steroids. V. A Kinetic Study in Basic and Acidic Media
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Effects of the β-methyl group at C-10 and some oxygen functions (=O, OH, OAc) at C-11, C-17, and C-20 on the rates of hydrogenation of 3-oxo-4-ene steroids have been studied with palladium catalyst in pyridine or THF/HBr as solvent.In contrast to the hydrogenation in pyridine, the rate in THF/HBr was greatly depressed by the presence of 10β-methyl group.The reactivity of the steroids was enhanced by the oxygen functions, in particular, by 11, 17-dioxo group.The effects of the substituents are discussed from a mechanistic consideration based on the obtained results.
- Nishimura, Shigeo,Momma, Yasuhiro,Kawamura, Hideo,Shiota, Michio
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p. 780 - 783
(2007/10/02)
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- An analysis of the metabolites of progesterone produced by isolated Sertoli cells at the onset of gametogenesis
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Sertoli cells isolated from 7 day old rats were maintained in culture and incubated with [14C]-progesterone for 20 h. The cells and media were extracted with ether/chloroform and the extracts chromatographed two-dimensionally on TLC and the radioactive metabolites visualized by autoradiography. Nine of the metabolites (constituting about 88% of total metabolite radioactivity) were identified by relative mobilities of the compounds and their derivatives in TLC and GC systems and by recrystallizations with authentic steroids as the following: 20α-hydroxypregn-4-en-3-one, 3α-hydroxy-5α-pregnan-20-one, 5α-pregnane-3α,20α-diol, 17β-hydroxy-5α-androstan-3-one, 5α-pregnane-3,20-dione, 17-hydroxypregn-4-ene-3,20-dione, testosterone, 5α-androstane-3α,17β-diol and androst-4-ene-3,17-dione. Over 71% of the metabolite radioactivity was due to 20α-hydroxypregn-4-en-3-one, the major metabolite. 5α-reduced pregnanes constituted about 12% and C19 steroids comprised about 2.9% of the radioactivity of the metabolites. Calculation of relative steroidogenic enzyme activities from initial reaction rates suggested the following activities in μunits/mg Sertoli cell protein: 20α-hydroxysteroid oxidoreductase (20α-HSO; 7.71), 5α-reductase (4.77), 3α-HSO (3.57), 17α-hydroxylase (0.93), 17β-HSO (0.34) and C17-C20 lyase (0.34). The relatively high rate of steroidogenic enzyme activities in the Sertoli cells of young rats may indicate that Sertoli cells are less dependent on Leydig cell steroidogenesis than has been assumed. Since nearly all the metabolites of progesterone and testosterone are now identified, it is possible to construct a picture of Sertoli cell steroidogenic activity.
- Wiebe,Tilbe,Buckingham
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p. 561 - 577
(2007/10/02)
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- NAD(P)H Models XV. Reduction of Δ4-3-ketosteroids via their iminium salts, by 1,4-dihydropyridine derivatives
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Pyrrolidinium salts derived from a series of 17-substituted Δ4-3-ketosteroids are reduced by 1-benzyl-1,4-dihydronicotinamide (BNAH) and 2,6-dimethyl-3,5-diethoxycarbonyl-1,4-dihydropyridine (Hantzsch ester, 1 eq.) to the corresponding isomeric 5α- and 5β-enamines which hydrolyse to the corresponding 3-ketosteroids.In the case of the Hantzsch ester reduction, proton transfer from the oxidized Hantzsch ester to the enamine results in the formation of iminium salts, which are further reduced to the corresponding ammonium salts.Mechanistic, stereochemical and biochemical implications of the reactions are discussed.
- Gase, Ronald A.,Pandit, Upendra K.
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p. 334 - 340
(2007/10/02)
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- Metabolism and Effects of Progesterone in the Human Endometrial Adenocarcinoma Cell Line HEC-1
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Human endometrial adenocarcinoma cells (HEC-1 line) were incubated with 14C-progesterone.Four major labeled metabolites, 3β-hydroxy 5α-pregnan-20-one, 5α-pregnane-3β,20α-diol, 20α-hydroxy-4-pregnen-3-one and 5α-pregnane-3,20-dione were separated by thin layer chromatography, further purified by high pressure liquid chromatography, and finally identified by addition of carriers and crystallization to constant specific activity.Among these metabolites, 5α-pregnane-3β,20α-diol seems characteristic of this cell line since its formation from labeled progesterone was not detected in normal endometrium or in 2 specimens of endometrial adenocarcinoma.The growth of HEC cells was unaffected by either progesterone or medroxyprogesterone acetate, a slowly metabolized progestin, at about 10-6 M levels but was inhibited by about 10-5 M concentrations of these compounds.
- Satyaswaroop, P. G.,Frost, A.,Gurpide, E.
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