- Preparation of androsta-1,4-diene-3,17-dione from sterols using Mycobacterium neoaurum VKPM Ac-1656 strain
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A product of microbiological cleavage of the sterols side chain, androsta-1,4-diene-3,17-dione, is toxic for bacteria, in particular, actinobacteria of the genera Mycobacterium and Arthrobacter. Sterols were transformed into androsta-1,4-diene-3,17-dione by culturing the M. neoaurum VKPM Ac-1656 strain in a high yield, provided that a sorbent was used for elimination of contact between the bacterial cells and the product. Unlike the cholesterol side chain, the more branched chains of phytosterols were cleaved in the presence of M. neoaurum at a high rate only under turbulent stirring of the culture medium, which intensified the formation of hydrocarbonate ion from NaNI3 in situ. Nauka/Interperiodica 2007.
- Molchanova,Andryushina,Savinova,Stytsenko,Rodina,Voishvillo
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- Bioconversion of 4-androstene-3,17-dione to androst-1,4-diene-3,17-dione by recombinant Bacillus subtilis expressing ksdd gene encoding 3-ketosteroid-Δ1-dehydrogenase from Mycobacterium neoaurum JC-12
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The enzyme 3-ketosteroid-Δ1-dehydrogenase (KSDD), involved in steroid metabolism, catalyzes the transformation of 4-androstene-3,17-dione (AD) to androst-1,4-diene-3,17-dione (ADD) specifically. Its coding gene was obtained from Mycobacterium neoaurum JC-12 and expressed on the plasmid pMA5 in Bacillus subtilis 168. The successfully expressed KSDD was analyzed by native-PAGE. The activities of the recombinant enzyme in B. subtilis were 1.75 U/mg, which was about 5-fold that of the wild type in M. neoaurum. When using the whole-cells as catalysts, the products were analyzed by tin-layer chromatography and high-performance liquid chromatography. The recombinant B. subtilis catalyzed the biotransformation of AD to ADD in a percent conversion of 65.7% and showed about 18 folds higher than M. neoaurum JC-12. The time required for transformation of AD to ADD was about 10 h by the recombinant B. subtilis, much shorter than that of the wild-type strain and other reported strains. Thus, the efficiency of ADD production could be improved immensely. For industrial applications, the recombinant B. subtilis containing KSDD provides a new pathway of producing steroid medicines.
- Zhang, Wenqing,Shao, Minglong,Rao, Zhiming,Xu, Meijuan,Zhang, Xian,Yang, Taowei,Li, Hui,Xu, Zhenghong
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- Synthesis of steroidal [1,2,4]triazolo[1,5-a]pyrimidines and their antiproliferative activities
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— A facile strategy for the synthesis of steroidal [1,2,4]triazolo[1,5-a]pyrimidines 5a-g and 6a-g has been accomplished via a one-pot reaction of steroidal ketones, aromatic aldehydes and 3-amino-1,2,4-triazole in the presence of potassium tert-butoxide in refluxing tert-butanol. All the synthesized heterosteroids were evaluated for in vitro antiproliferative activity against human cancer cells by sulforhodamine B (SRB) assays. The preliminary results showed that compounds 6a and 6e possessed potent antiproliferative activities.
- Fan, Ning-Juan,Tang, Jiang-Jiang,Li, Yuan-Feng,Bai, Yu-Bin,Zhao, Xiao-Min
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p. 822 - 831
(2019/08/01)
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- Synthesis of 3β-methyl ether of dehydroepiandrosterone by biotransformation of 3β-methyl ether of cholesterol with cells of mycobacteria Mycobacterium sp.
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3p-Methyl ether of dehydroepiandrosterone was obtained by microbiological transformation of 3?-methyl ether of cholesterol with Mycobacterium sp. Androstane-3,17-dione, androst-4-ene-3,17-dione, and androsta-1,4-diene-3,17-dione were minor transformation products.
- Andryushina,Stytsenko,Karpova,Yaderets,Zavarzin,Kurilov
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p. 2355 - 2358
(2020/02/18)
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- Hemisynthesis, computational and molecular docking studies of novel nitrogen containing steroidal aromatase inhibitors: Testolactam and testololactam
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Testololactone (10) and testolactone (11) represent aromatase inhibitors containing lactone rings. We previously reported their hemisynthesis from the most common phytosterols, which are highly abundant in nature. Herein, we report the synthesis of their nitrogen congeners: testololactam (3) and testolactam (8). The reaction process involves the conversion of 4-androstene-3,17-dione to its corresponding oxime using hydroxylamine hydrochloride, whose Beckmann rearrangement under acid conditions yielded the desired testololactam (3). However, testolactam (8) was formed by the Beckmann rearrangement of the oxime (7) of 1,4-androstene-3,17-dienone (6). This expeditious reaction scheme may be exploited for the bulk production of testololactam (3) and testolactam (8). Theoretical DFT studies concerning the structural and electronic properties of all the end products were carried out using the Becke three-parameter Lee-Yang-Parr function (B3LYP) and 6-31G(d,p) level of theory. Molecular electrostatic potential map and frontier orbital analysis were carried out. The HOMO-LUMO energy gap was calculated, which allowed the calculation of relative reactivity descriptors like chemical hardness, chemical inertness, chemical potential, nucleophilicity and electrophilicity index of the synthesized products. The molecular docking studies of testololactam (3), testolactam (8) and testololactone (10), with aromatase (CYP19) revealed binding free energies of (ΔGb) = -9.85, -9.62 and -10.14 kcal mol-1 respectively, compared to the standard testolactone (11), a well-known aromatase inhibitor sold under the brand name TESLAC, which exhibited a binding free energy (ΔGb) of -10.29 kcal mol-1 with an inhibition constant Ki of 28.87 nM. The docking study revealed that the nitrogen congeners exhibit a relatively lower but appreciable therapeutic efficiency to be used as aromatase inhibitors.
- Lone, Shabir H.,Bhat, Muzzaffar A.,Lone, Rayees A.,Jameel, Salman,Lone, Javeed A.,Bhat, Khursheed A.
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p. 4579 - 4589
(2018/03/21)
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- Hemisynthesis of 2,3,4-13C3-1,4-androstadien-3,17-dione: A key precursor for the synthesis of 13C3-androstanes and 13C3-estranes
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In this contribution, we describe two simple and efficient routes for the preparation of keto-aldehyde 1, a key intermediate for the synthesis of 13C3-androstanes and 13C3-estranes. In the first route, the targeted aldehyde 1 was obtained in 40% overall yield from 1,4-androstadien-3,17-dione (3 mmol scale) via a two-step sequence involving a one-pot, abnormal ozonolysis/sulfur oxidation/retro-Michael/ozonolysis process. Alternatively, a second route from 4-androsten-3,17-dione, using a six-step sequence, was optimized to produce 40 mmol batches of the key intermediate 1 in 42% overall yield. At the final stage, the A-ring was reconstructed through a Wittig reaction with the 1-triphenylphosphoranylidene-13C3-2-propanone 2, followed by an intramolecular condensation assisted by thioacetic acid via a Michael addition/retro-Michael reaction sequence to provide 2,3,4-13C3-1,4-androstadien-3,17-dione.
- Berthonneau, Clément,Nun, Pierrick,Rivière, Matthieu,Pauvert, Mickael,Dénès, Fabrice,Lebreton, Jacques
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p. 3727 - 3737
(2018/04/14)
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- New product identification in the sterol metabolism by an industrial strain Mycobacterium neoaurum NRRL B-3805
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Mycobacterium neoaurum NRRL B-3805 metabolizes sterols to produce androst-4-en-3,17-dione (AD) as the main product, and androsta-1,4-dien-3,17-dione, 9α-hydroxy androst-4-en-3,17-dione and 22-hydroxy-23,24-bisnorchol-4-en-3-one have been identified as by-products. In this study, a new by-product was isolated from the metabolites of sterols and identified as methyl 3-oxo-23,24-bisnorchol-4-en-22-oate (BNC methyl ester), which was proposed to be produced via the esterification of BNC catalyzed by an O-methyltransferase using S-adenosyl-L-methionine as the methyl group donor. These results might open a new dimension for improvement of the efficiency of microbial AD production by eliminating this by-product via genetic manipulation of the strain.
- Li, Xuemei,Chen, Xi,Wang, Yu,Yao, Peiyuan,Zhang, Rui,Feng, Jinhui,Wu, Qiaqing,Zhu, Dunming,Ma, Yanhe
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supporting information
p. 40 - 45
(2018/02/21)
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- Microbial transformation of epiandrosterone by Aspergillus sydowii
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Incubation of epiandrosterone with Aspergillus sydowii MRC 200653 afforded ten metabolites. The fungal dehydrogenation of epiandrosterone is reported for the first time. The formation of the major metabolite, 6?-hydroxyandrost-4-ene-3,17-dione, involved first dehydrogenation to give a 4-ene and then hydroxylation at C-6?. Small amounts of the substrate were hydroxylated at C-1α, C-7α, C-7β and C-11α.
- Yildirim, Kudret,Kuru, Ali
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p. 718 - 721
(2016/12/30)
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- Phytosterols as precursors for the synthesis of aromatase inhibitors: Hemisynthesis of testololactone and testolactone
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Using β-sitosterol and stigmasterol as precursor materials, a concise and efficient hemisynthesis of aromatase inhibitors: testololactone and testolactone was accomplished in a well-established reaction scheme. It involves highly effective Oppaneur oxidation of both β-sitosterol as well as stigmasterol to generate the required enone moiety in ring 'A' of the desired steroid system. The Oppaneur oxidation products of both β-sitosterol and stigmasterol were then subjected to oxidative cleavage of the side chain to produce 4-androstene-3,17-dione. Baeyer-Villiger oxidation of 4-androstene-3,17-dione using m-CPBA yielded testololactone. Dehydrogenation of 4-androstene-3,17-dione using phenylselenyl chloride in ethyl acetate followed by selenoxide elimination with H2O2 in dichloromethane furnished androstenedienone. Baeyer-Villiger oxidation of the resulting androstenedienone yielded the desired testolactone (overall yield 33%). This expeditious reaction scheme may be exploited for the bulk production of aromatase inhibitors (especially testolactone marketed under the brand name Teslac) from the most abundant and naturally occurring phytosterols like β-sitosterol.
- Lone, Shabir H.,Bhat, Khursheed A.
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p. 164 - 168
(2015/03/04)
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- Structure and catalytic mechanism of 3-ketosteroid-Δ4-(5α)- dehydrogenase from Rhodococcus jostii RHA1 genome
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3-Ketosteroid Δ4-(5α)-dehydrogenases (Δ4-(5α)- KSTDs) are enzymes that introduce a double bond between the C4 and C5 atoms of 3-keto-(5α)-steroids. Here we show that the ro05698 gene from Rhodococcus jostii RHA1 codes for a flavoprotein with Δ4-(5α)-KSTD activity. The 1.6 A resolution crystal structure of the enzyme revealed three conserved residues (Tyr-319, Tyr-466, and Ser-468) in a pocket near the isoalloxazine ring system of the FAD co-factor. Site-directed mutagenesis of these residues confirmed that they are absolutely essential for catalytic activity. A crystal structure with bound product 4-androstene-3,17-dione showed that Ser-468 is in a position in which it can serve as the base abstracting the 4β-proton from the C4 atom of the substrate. Ser-468 is assisted by Tyr-319, which possibly is involved in shuttling the proton to the solvent. Tyr-466 is at hydrogen bonding distance to the C3 oxygen atom of the substrate and can stabilize the keto-enol intermediate occurring during the reaction. Finally, the FAD N5 atom is in a position to be able to abstract the 5α-hydrogen of the substrate as a hydride ion. These features fully explain the reaction catalyzed by Δ4-(5α)-KSTDs.
- Van Oosterwijk, Niels,Dijkstra, Bauke W.,Knol, Jan,Dijkhuizen, Lubbert,Van Der Geize, Robert
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p. 30975 - 30983,9
(2020/08/31)
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- Activity of 3-ketosteroid 9α-hydroxylase (KshAB) indicates cholesterol side chain and ring degradation occur simultaneously in Mycobacterium tuberculosis
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Mycobacterium tuberculosis (Mtb), a significant global pathogen, contains a cholesterol catabolic pathway. Although the precise role of cholesterol catabolism in Mtb remains unclear, the Rieske monooxygenase in this pathway, 3-ketosteroid 9α-hydroxylase (KshAB), has been identified as a virulence factor. To investigate the physiological substrate of KshAB, a rhodococcal acyl-CoA synthetase was used to produce the coenzyme A thioesters of two cholesterol derivatives: 3-oxo-23,24-bisnorchol-4- en-22-oic acid (forming 4-BNC-CoA) and 3-oxo-23,24-bisnorchola- 1,4-dien-22-oic acid (forming 1,4-BNC-CoA). The apparent specificity constant (kcat/Km) of KshAB for the CoA thioester substrates was 20-30 times that for the corresponding 17-keto compounds previously proposed as physiological substrates. The apparent KmO2 was 90 ± 10 μM in the presence of 1,4-BNC-CoA, consistent with the value for two other cholesterol catabolic oxygenases. The Δ1 ketosteroid dehydrogenase KstD acted with KshAB to cleave steroid ring B with a specific activity eight times greater for a CoA thioester than the corresponding ketone. Finally, modeling 1,4-BNC-CoA into the KshA crystal structure suggested that the CoA moiety binds in a pocket at the mouth of the active site channel and could contribute to substrate specificity. These results indicate that the physiological substrates of KshAB are CoA thioester intermediates of cholesterol side chain degradation and that side chain and ring degradation occur concurrently in Mtb. This finding has implications for steroid metabolites potentially released by the pathogen during infection and for the design of inhibitors for cholesterol-degrading enzymes. The methodologies and rhodococcal enzymes used to generate thioesters will facilitate the further study of cholesterol catabolism.
- Capyk, Jenna K.,Casabon, Israel,Gruninger, Robert,Strynadka, Natalie C.,Eltis, Lindsay D.
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experimental part
p. 40717 - 40724
(2012/06/29)
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- INFANT FORMULA CONTAINING AN AROMA COMPOSITION FOR USE AS FRAGRANCE
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The invention relates to a nutraceutical composition such as infant formula or infant food comprising a) a defined aroma composition; b) a methodology for developing, maintaining certain aroma constituents in the infant formula and an aroma or fragrance composition to be used to increase the acceptance of a person or an object by the baby or new born.
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- Endogenous boldenone-formation in cattle: Alternative invertebrate organisms to elucidate the enzymatic pathway and the potential role of edible fungi on cattle's feed
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Although β-boldenone (bBol) used to be a marker of illegal steroid administration in calves, its endogenous formation has recently been demonstrated in these vertebrates. However, research on the pathway leading to bBol remains scarce. This study shows the usefulness of in vivo invertebrate models as alternatives to vertebrate animal experiments, using Neomysis integer and Lucilia sericata. In accordance with vertebrates, androstenedione (AED) was the main metabolite of β-testosterone (bT) produced by these invertebrates, and bBol was also frequently detected. Moreover, in vitro experiments using feed-borne fungi and microsomes were useful to perform the pathway from bT to bBol. Even the conversion of phytosterols into steroids was shown in vitro. Both in vivo and in vitro, the conversion of bT into bBol could be demonstrated in this study. Metabolism of phytosterols by feed-borne fungi may be of particular importance to explain the endogenous bBol-formation by cattle. To the best of our knowledge, it is the first time the latter pathway is described in literature.
- Verheyden,Noppe,Zorn,Van Immerseel,Bussche, J. Vanden,Wille,Bekaert,Janssen,De Brabander,Vanhaecke
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experimental part
p. 161 - 170
(2011/03/19)
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- Microbial side-chain degradation of ergosterol and its 3-substituted derivatives: A new route for obtaining of deltanoids
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The strain of Mycobacterium sp. VKM Ac-1815D was found to convert ergosterol and its 3-acetate mainly to androst-4-ene-3,17-dione (AD) thus demonstrating ability to reduce 7(8)-double bond and hydrolyze sterol ester in addition to oxidation of 3β-hydroxy group,δ5-δ4 isomerization and side-chain degradation. Ergosterol bioconversion in the presence of isoflavones and ions of some bivalent metals known inhibitors of 3-hydroxysteroid dehydrogenase, did not alter products composition. Protection of ergosterol 3β-hydroxyl with methoxymethyl group allowed the formation of bioconversion products retaining the δ 5,7-configuration. The major product was identified by mass-spectrometry and proton NMR as 3- methoxymethoxy-androsta-5,7-diene-17-one (MA). TheMAproducing activity was found to be inducible with sterols, cholestenone or lithocholic acid, but not with dehydroepiandrosterone, AD, androsta-1,4- ene-3,17-dione or organic acids. Under the optimized conditions, the yield ofMAreached 5 g/l from 10 g/l O-methoxymethyl-ergosterol (approx. 60% molar conversion) for 120 h. The results might be applied at the production of novel vitamin D derivatives.
- Dovbnya, Dmitry V.,Egorova, Olga V.,Donova, Marina V.
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experimental part
p. 653 - 658
(2010/09/04)
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- A practical Δ1-dehydrogenation of Δ4-3-keto-steroids with DDQ in the presence of TBDMSCl at room temperature
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A mild and efficient Δ1-dehydrogenation of Δ4-3-keto-steroids with DDQ in the presence of tertbutyldimethylchlorosilane at room temperature was developed.
- Chen, Kaixiong,Liu, Chang,Deng, Le,Xu, Guangyu
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experimental part
p. 513 - 516
(2010/06/21)
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- A concise effective deprotection of spiro 3-cyclic thiaza ketal of steroidal 1,4-dien-3-one
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An effective deprotective method of spiro 3-cyclic thiaza ketal of steroidal 1,4-dien-3-ones using alkyl vinyl ether in the presence of protic acid followed by the treatment of aqueous alkali was described. This novel protocol could be fulfilled under mild condition with high yield. The mechanism mediated by a carbonium ion formed in situ was clarified by the capture of the cleaved fragment.
- Zhang, Bei Na,Chen, Ying,Zhang, Qian,Xia, Peng
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- Microbial hydroxylation of pregnenolone derivatives
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Pregnenolone (1) and pregnenolone acetate (2) were incubated with the fungi Cunninghamella elegans, Rhizopus stolonifer and Gibberella fujikuroi. Incubation of 1 with C. elegans yielded metabolites, 3 β,7 β,11 α-trihydroxypreg-5-en-20-one (3), 3 β,6 α,11 α,12 β,15 β-pentahydroxypreg-4-en-20-one (4) and 3 β,6 β,11 α-trihydroxypreg-4-en-20-one (5), while incubation with G. fujikuroi yielded two known metabolites, 3 β,7 β-dihydroxypregn-5-en-20-one (6) and 6 β,15 β-dihydroxypreg-4-ene-3,20-dione (7). Metabolites 4 and 5 were found to be new. Fermentation of 2 by C. elegans yielded four known oxidative metabolites, 1, androsta-1,4-diene-3,17-dione (8), 6 β,15 β-dihydroxyandrost-4-ene-3,17-dione (9) and 11 α,15 β-dihydroxypreg-4-ene-3,20-dione (10). Fermentation of 2 with R. stolonifer yielded two known metabolites, 11 α-hydroxypreg-4-ene-3,20-dione (11) and 7. Compounds 1-11 were screened for their cholinesterase inhibitory activity in a mechanism-based assay.
- Choudhary, Muhammad Iqbal,Batool, Iffat,Shah, Syed Adnan Ali,Nawaz, Sarfraz Ahmad,Atta-ur-Rahman
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p. 1455 - 1459
(2007/10/03)
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- Microbial side-chain degradation of progesterone I: Optimization of the transformation conditions
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The microbial side-chain degradation of progesterone for the production of C-19 androgens was investigated. Thirty seven locally isolated fungal cultures were screened for their ability to degrade the side-chain of progesterone. Fusarium dimerum showed the greatest bioconversion efficiency and was selected for further studies. 50% of the substrate was converted to androstenedione after 24 hrs. 72 hrs old culture was able to produce maximum yields of testosterone, androstenedione and androstadienedione. The maximum conversion activities (90%) of progesterone were recorded at pH 7. The capacity of the fungus to degrade the side-chain of progesterone was greatly diminished on using high concentration of progesterone. The bioconversion estimates sharply decreased by using glucose syrup, corn steep liquor and glucose-corn steep media.
- Adham, Nehad Z.,El-Tayeb, Osama M.,Hashem, Abdel-Gawad M.,El-Refai, Heba A.,Sallam, Lotfy A.
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p. 250 - 255
(2007/10/03)
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- Iodine(V) reagents in organic synthesis. Part 4. o-Iodoxybenzoic acid as a chemospecific tool for single electron transfer-based oxidation processes
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o-Iodoxybenzoic acid (IBX), a readily available hypervalent iodine(V) reagent, was found to be highly effective in carrying out oxidations adjacent to carbonyl functionalities (to form α, β-unsaturated carbonyl compounds) and at benzylic and related carbon centers (to form conjugated aromatic carbonyl systems). Mechanistic investigations led to the conclusion that these new reactions are initiated by single electron transfer (SET) from the substrate to IBX to form a radical cation which reacts further to give the final products. Fine-tuning of the reaction conditions allowed remarkably selective transformations within multifunctional substrates, elevating the status of this reagent to that of a highly useful and chemoselective oxidant.
- Nicolaou,Montagnon,Baran,Zhong
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p. 2245 - 2258
(2007/10/03)
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- Lithocholic Acid Side-chain Cleavage to Produce 17-Keto or 22-Aldehyde Steroids by Pseudomonas putida strain ST-491 Grown in the Presence of an Organic Solvent, Diphenyl Ether
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We devised a method to screen for microorganisms capable of growing on bile acids in the presence of organic solvents and producing organic solvent-soluble derivatives. Pseudomonas putida biovar A strain ST-491 isolated in this study produced decarboxylated derivatives from the bile acids. Strain ST-491 grown on 0.5% lithocholic acid catabolized approximately 30% of the substrate as a carbon source, and transiently accumulated in the medium androsta-1,4-diene-3,17-dione in an amount of corresponding to 5% of the substrate added. When 20% (v/v) diphenyl ether was added to the medium, 60% of the substrate was converted to 17-keto steroids (androst-4-ene-3,17-dione-like steroid, androsta-1,4-diene-3,17-dione) or a 22-aldehyde steroid (pregna-1,4-dien-3-on-20-al). Amounts of the products were responsible for 45, 10, and 5% of the substrate, respectively. In the presence of the surfactant Triton X-100 instead of diphenyl ether, 40% of the substrate was converted exclusively to androsta-1,4-diene-3,17-dione.
- Suzuki, Yasumasa,Doukyu, Noriyuki,Aono, Rikizo
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p. 2182 - 2188
(2007/10/03)
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- Stereospecific oxidation of 3β-hydroxysteroids by persolvent fermentation with Pseudomonas sp. ST-200
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Pseudomonas sp. strain ST-200 isolated from a humus soil effectively oxidizes cholesterol dissolved in organic solvents but not that suspended in the growth medium. The organism does not assimilate cholesterol. This organism oxidized a variety of 5α- or 5-ene-steroids dissolved in organic solvent. First, the 3β-OH group was oxidized to a ketone group. The 3α-OH group was scarcely oxidized. Successively, C-6 position of 5-ene-steroids was hydroxylated, and a double bond of 5-ene-steroids was transferred from Δ5 to Δ4. Then, the 6-OH group was oxidized to a ketone group. Persolvent fermentation with ST-200 would provide an effective, convenient, and stereospecific method to oxidize the C-3 and C-6 positions of steroids.
- Aono, Rikizo,Doukyu, Noriyuki
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p. 1146 - 1151
(2007/10/03)
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- 2-iodo-3-keto-Δ4 steroids, process for their production, as well as their further processing
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The new intermediate products of general formula I STR1 in which R1 stands for a hydrogen atom or a straight-chain or branched alkyl group with 1 to 4 carbon atoms, R2 stands for a hydrogen atom or a methyl group, R3 stands for a hydrogen atom, R4 stands for an acyloxy group with 1 to 4 carbon atoms in the acyl radical or R3 and R4 together stand for a keto-oxygen atom, are suitable in an excellent way for introducing a Δ1 double bond in the steroid skelton with the simultaneous presence of a Δ4 double bond, as well as a saturated carbonyl group, by clevage of hydrogen iodide with a base in an amidic solvent at elevated temperature. If R2 stands for a hydrogen atom, the A-ring is aromatized after the hydrogen iodide cleavage. For the production of a new intermediate products, special iodization processes, which partially also allow a stereoselective control of the iodization, are used.
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- Selective 1-Dehydrogenation of Progesterone by Aspergillus fumigatus
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Fermentation of progesterone with acetone-dried cells of Aspergillus fumigatus in the presence of β-cyclodextrin yields pregna-1,4-diene-3,20-dione as the single isolable product.
- Garai, Subhadra,Banerjee, Sukdeb,Mahato, Shashi B.
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p. 408 - 409
(2007/10/03)
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- Rearrangement of 3-Thioxo-Δ1,4-steroids, a New Approach of Steroid Thiols
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3-Thioxoandrosta-1,4-dien-17-one (1) is subjected to a dienthion-thiophenol reaerangement in aprotic and protic solvents in the presence of an acid catalyst resulting in the formation of 1-(acetylthio)-4-methylestra-1,3,5(10)-trien-17-one (2), 1-mercapto-4-methylestra-1,3,5(10)-trien-17-one (3), and the dimer 1,1'-(dithio)bis (4) as the reaction products.The mercapto compound 3 tends to be autoxidized to the sulfide 4. - Keywords: 3-Thioxoandrosta-1,4-dien-17-one, rearrangement of / Thioestratriene
- Moeller, Stephanie,Weiss, Dieter,Beckert, Rainer
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p. 1397 - 1400
(2007/10/02)
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- Investigation into the Reaction between 1α,5α-Epidithio Steroids and Electrophilic Halogenating Reagents: Aspects of the Chemistry of Thiosulphenyl Chlorides and Thiiranium Ions
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The reaction of sulphuryl dichloride with 1α,5α-epidithioandrostane-3α,17β-diol diacetate afforded a ca. 1:1 mixture of 1α-(chlorodithio) androst-5-ene-3α,17β-diol diacetate and 4β-chloro-1α,5α-epidithioandrostane-3α,17β-diol diacetate.These labile intermediates reacted with various nucleophiles to give a variety of products, many of which represent new or little known classes of thiosteroidal compounds.A number of these appear to arise from an unusual thiiranium ion intermediate.Possible explanations for the differing regioselectivity in the ring opening of the thiiranium ion are advanced.
- Barton, Derek H. R.,Hesse, Robert H.,Lindell, Stephen D.,Pechet, Maurice M.
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p. 2845 - 2854
(2007/10/02)
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- CHROMIUM(VI) BASED OXIDANTS-1. CHROMIUM PEROXIDE COMPLEXES AS VERSATILE, MILD, AND EFFICIENT OXIDANTS IN ORGANIC SYNTHESIS.
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The preparation of 2,2'-bipyridylchromium peroxide, pyridinechromium peroxide, and chromium peroxide etherate is described. 2,2'-Bipyridylchromium peroxide converts different classes of alcohols to the carbonyl compounds.In 1,2-diols C-C bond cleavage occurs extensively. α-Hydroxy acids are decarboxylated quantitatively.Oximes are converted to their carbonyl compounds and thiols to their disulfides, dihydroxy phenolic compounds to quinones, benzyl amine to benzaldehyde, aromatic amines to their azo compounds, anthracene and phenanthrene to their quinones.Pyridinechromium peroxide converts different classes of alcohols efficiently to the carbonyl compounds, thiols to their disulfides, anthracene to anthraquinone.Mandelic and benzilic acids are decarboxylated very efficiently.Chromium peroxide etherate is an efficient reagent for the oxidation of different classes of alcohols to their carbonyl compounds.
- Firouzabadi, H.,Iranpoor, N.,Kiaeezadeh, F.,Toofan, J.
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p. 719 - 726
(2007/10/02)
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- AN EXCEPTIONALLY MILD, PHASE TRANSFER CATALYZED METHOD FOR THE CONVERSION OF THIOCARBONYL COMPOUNDS TO CARBONYLS
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The thiocarbonyl group of thioketones, dithioesters, thioamides, and thioureas can be converted to the carbonyl function by treatment with sodium hydroxide under phase transfer conditions.
- Alper, Howard,Kwiatkowska, Caroline,Petrignani, Jean-Francois,Sibtain, Fazle
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p. 5449 - 5450
(2007/10/02)
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- Unusual Enolizations in 19-Nor-3-ketosteroids
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The direction of enolization of 19-nor-3-ketosteroids was found to proceed predominantly towards C-2 irrespective of the ring junction at C-5.
- Abul-Hajj, Yusuf J.
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p. 1479 - 1481
(2007/10/02)
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- ISOLATION AND THE STRUCTURE OF THE PRODUCTS OF CHOLESTEROL BIODEGRADATION BY THE MUTANT Mycobacterium sp. CCM 3529
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During the biodegradation of cholesterol by the mutant Mycobacterium sp.CCM 3529 1,4-androstadiene-3,17-dione (II) is formed as the main product.The following compounds were identified as characteristic by-products: a mixture of methyl esters IV and V in a 1:3 ratio, 4-androstene-3,17-dione (III), 22-hydroxy derivative I, 17β-hydroxy-4-androsten-3-one (XIII) and 17β-hydroxy-1,4-androstadien-3-one (XII).
- Mickova, Ruzena,Hutlova, Hana,Pihera, Pavel,Protiva, Jiri,Schwarz, Vladimir
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p. 1110 - 1113
(2007/10/02)
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- BIODEGRADATION OF CHOLESTEROL BY A MUTANT OF THE Mycobacterium SPECIES
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The biodegradation of cholesterol by the Mycobacterium mutant CCM 3528 gave rise to 22-hydroxy-23,24-bisnorchola-1,4-diene-3-one (I) as the main product.The identified by-products were 24-norchola-1,4-diene-3,22-dione (IX), androsta-1,4-diene-3,17-dione (XV) and their unsaturated analogues, X and XVI respectively.
- Schwarz, Vladimir,Pihera, Pavel,Protiva, Jiri,Mickova, Ruzena
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p. 2713 - 2720
(2007/10/02)
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- Microbial Oxidation of Sterol Side-Chains
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Several sterol metabolising microorganisms, Pseudomonas convexa, P. stutzeri, Micrococcus sp., Cephalosporium longisporum and Moraxella sp. were isolated from soil on 2-cyclopentyl-6-methyl heptane and cholestane as carbon sources.All these organisms were shown to have the capacity of oxidizing the eight carbon side chain of cholesterol.Excepting P. convexa, the organisms needed a chelating agent for prevention of steroid ring degradation.The Moraxella sp. proved to be the most versatile as it degraded cholesterol derivatives such as 3β-methoxy cholest-5-ene, 3β-chloro cholest-5-ene, 3,5-cyclocholestan-6-one and potassium cholesteryl sulphate to the corresponding 17-keto steroids in 10-50percent yield in shake flasks.It also gave high yields of estrone from both 19-hydroxy-3β-acetoxy cholest-5-ene and 19-hydroxy-3β-acetoxy sitost-5-ene.Two new enzymes one carrying out the oxidative O-demethylation of 6β-methoxy 3,5-cyclocholestane and the other, the isomerisation of i-steroids to normal 3β-hydroxy-Δ5 steroids were discovered.Immobilized Moraxella cells in agar carried out the side chain degradation of cholesteryl sulphate to yield 3β-hydroxy androst-5-en-17-one sulphate and the 19-hydroxy-3β-acetoxy derivatives of both cholesterol and sitosterol to estrone in high yields.The half life of entrapped cells was estimated to be 28 days.
- Bhattacharyya, P. K.,Rao, M. Krishna,Natarajan, Rama Devi,Ramgopal, Malathi,Madyastha, Prema,Madyastha, K. M.
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- Reductive Cleavage of the 9,10-Bond in 11-Oxygenated Steroids: a New Method for the Partial Synthesis of the Vitamin D Skeleton
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11-Oxygenated steroids with a ring A dienone system are reduced in non-protic media with cleavage of the 9,10-bond, and the resulting 9,10-secosteroids (2) or (5) were converted into 9,10-secocholesta-1,3,5(10)-triene-3-ol (12), an unknown isomer of cholecalciferol (vitamin D3).
- Ananthanarayan, T. P.,Magnus, Philip,Norman, Anthony W.
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p. 1096 - 1098
(2007/10/02)
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- Microbiological Transformations. XVI. Transformation of 5α- and 5β-Dihydro, and 1- and 6-Dehydro Derivatives of Testosterone and Androstenedione by Means of Rhodotorula mucilaginosa Strain
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The following transformation of 5α- and 5β-dihydro derivatives of testosterone and androstenedione by means of Rhodotorula mucilaginosa has been observed: reduction of the carbonyl group on C-3 to both possible alcohols in the 5α-series and only to one alcohol (3α) in the 5β-series.In the transformation of 1- and 6-dehydro derivatives of testosterone and androstenedione, reduction in ring A was completely inhibited.The carbonyl or hydroxy groups at C-17 in both series of substrates underwent interconversion.
- Draczynska, Bozena,Tlomak, Elzbieta,Dmochowska-Gladysz, Jadwiga,Siewinski, Antoni
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- A Practical Catalytic Method for the Preparation of Steroidal 1,4-Dien-3-ones by Oxygen Atom Transfer from Iodoxybenzene to Diphenyl Diselenide
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The dehydrogenation of steroidal 3-ketones can be accomplished in high yield using benzeneseleninic anhydride generated in situ by efficient oxygen atom transfer from iodoxybenzene to catalytic amounts of diphenyl diselenide.An experimentally convenient and economical development of this catalytic cycle is the use of meta-iodoxybenzoic acid which both avoids chromatography and allows recovery of meta-iodobenzoic acid and diphenyl diselenide. 12-Hydroxy- and 12-keto-steroids are also dehydrogenerated very efficiently using this catalytic process.
- Barton, Derek H. R.,Godfrey, Christopher R. A.,Morzycki, Jacek W.,Motherwell, William B.,Ley, Steven V.
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p. 1947 - 1952
(2007/10/02)
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- Oxygen Atom Transfer from Iodylbenzene to Diphenyl Diselenide - A Convenient Method for Dehydrogenation of Steroidal 3-Ketones
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Steroidal 3-ketones are smoothly dehydrogenated in high yield using benzeneseleninic anhydride generated in situ by oxygen atom transfer from iodylbenzene, PhIO2, to catalytic amounts of diphenyl diselenide; use of meta-iodylbenzoic acid in the above cycle has led to the development of an economical and experimentally convenient method avoiding chromatographic separations and with recovery of the m-iodobenzoic acid and the diphenyl diselenide.
- Barton, Derek H. R.,Morzycki, Jacek W.,Motherwell, William B.,Ley, Steven V.
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p. 1044 - 1045
(2007/10/02)
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