- Covalent Immobilization of Human Placental 17β-Hydroxysteroid Dehydrogenase Type 1 onto Glutaraldehyde Activated Silica Coupled with LC-TOF/MS for Anti-Cancer Drug Screening Applications
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Human 17β-hydroxysteroid dehydrogenase type 1 (17β-HSD1), a potential target in breast cancer prevention and therapy, was extracted from human placenta and immobilized on nonporous silica (～5?μm) with a covalent method for the first time. The optimum initial enzyme concentration and immobilization time during the immobilization process were 0.42?mg?mL?1 and 12?h, repectively. The binding was confirmed by scanning electron microscope (SEM) and infrared spectroscopy (FT-IR). It could improve the pH, thermal and storage stability compared to free enzyme. Moreover, the immobilized enzyme could be reused at least four times. A screening method based on it coupled with liquid chromatography–time-of-flight mass spectrometer (LC-TOF/MS) was established, and the half-maximal inhibitory concentration (IC 50) of apigenin for the immobilized enzyme was 291?nM. Subsequently, 10 natural products were evaluated leading to inhibition of the activity of 17β-HSD1 at the concentration of 25?μM, and six of them inhibit the activity over 50%.
- Bai, Yin,Zhou, Wen-Di,Mu, Xian-Min,Zhang, Qian,Yu, Chen,Di, Bin,Su, Meng-Xiang
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- STEREOSELECTIVE SYNTHESIS OF (+)-TESTOSTERONE VIA INTRAMOLECULAR 1,3-DIPOLAR CYCLOADDITION OF NITRILE OXIDE
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A new approach for construction of the A/B ring system of steroids was developed by way of an intramolecular 1,3-dipolar cycloaddition of a nitrile oxide 4, followed by an incorporation of a C3 unit.A highly stereocontrolled synthesis of (+)-testosterone 1 was accomplished by this strategy. Key Words: Steroids, testosterone, 1,3-dipolar cycloaddition, nitrile oxide, chiral synthesis
- Ihara, Masataka,Tokunaga, Yuji,Taniguchi, Nobuaki,Fukumoto, Keiichiro
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- Influence of whole microalgal cell immobilization and organic solvent on the bioconversion of androst-4-en-3,17-dione to testosterone by Nostoc muscorum
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The use of free, immobilized and reused immobilized cells of the microalga Nostoc muscorum was studied for bioconversion of androst-4-en-3,17-dione (AD) to testosterone in hexadecane. Among polymers such as agar, agarose, κ-carrageenan, polyacrylamide, polyvinyl alcohol, and sodium alginate that were examined for cell entrapment, sodium alginate with a concentration of 2% (w/v) proved to be the proper matrix for N. muscorum cells immobilization. The bioconversion characteristics of immobilized whole algal cells at ranges of temperatures, substrate concentrations, and shaking speeds were studied followed by a comparison with those of free cells. The conditions were 30°C, 0.5. g/L, and 100. rpm, respectively. The immobilized N. muscorum showed higher yield (72 ± 2.3%) than the free form (24 ± 1.3%) at the mentioned conditions. The bioconversion yield did not decrease during reuse of immobilized cells and remained high even after 5 batches of bioreactions while Na-alginate 3% was used; however, reuse of alginate 2% beads did not give a satisfactory result.
- Arabi,Yazdi, M. Tabatabaei,Faramarzi
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- Skin permeation of testosterone and its ester derivatives in rats
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To establish the optimum conditions for improving the transdermal delivery of testosterone, we studied the relationship between the lipophilicity of testosterone ester derivatives and the rat skin permeation rate of testosterone. We performed a rat skin permeation study of testosterone and its commercially available ester derivatives, testosterone hemisuccinate, testosterone propionate and testosterone-17β-cypionate, using an ethanol/water co-solvent system. The aqueous solubility and rat skin permeation rate of each drug, saturated in various compositions of an ethanol/water system, was determined at 37°C. The aqueous solubility of testosterone and its ester derivatives increased exponentially as the volume fraction of ethanol increased up to 100% (v/v). The stability of testosterone propionate in both the skin homogenate and the extract was investigated to observe the enzymatic degradation during the skin permeation process. Testosterone propionate was found to be stable in the isotonic buffer solution and in the epidermis-side extract for 10 h at 37°C. However, in the skin homogenate and the dermis-side extract testosterone propionate rapidly degraded producing testosterone, implying that testosterone propionate rapidly degraded to testosterone during the skin permeation process. The steady-state permeation rates of testosterone in the ethanol/water systems increased exponentially as the volume fraction of ethanol increased, reaching the maximum value (2.69 ± 0.69 μg cm-2h-1) at 70% (v/v) ethanol in water, and then decreasing with further increases in the ethanol volume fraction. However, in the skin permeation study with testosterone esters saturated in 70% (v/v) ethanol in water system, testosterone esters were hardly detected in the receptor solution, probably due to the rapid degradation to testosterone during the skin permeation process. Moreover, a parabolic relationship was observed between the permeation rate of testosterone and the log P values of ester derivatives. Maximum flux was achieved at a log P value of around 3 which corresponded to that of testosterone (log P = 3.4). The results showed that the skin permeation rate of testosterone and its ester derivatives was maximized when these compounds were saturated in a 70% ethanolic solution. It was also found that a log P value of around 3 is suitable for the skin permeation of testosterone related compounds.
- Kim, Mi-Kyeong,Lee, Chi-Ho,Kim, Dae-Duk
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- DEVELOPMENTAL PATTERN OF Δ5 3β-HYDROXYSTEROID DEHYDROGENASE ACTIVITY IN ISOLATED RAT LEYDIG CELLS
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A direct method for determination of Δ5 3β-hydroxysteroid dehydrogenase (3β-HSD) activity was employed in isolated Leydig cells (LC) derived from rats on fetal day 19 (F19) and postnatal (N) days 1, 12, 24, 34 and 45 and adults.The activity of 3β-HSD in the adult LC was 1.15 +/- 0.02 (μmole/μg DNA/hr, mean +/- SEM, n=73).Activities in the other groups, expressed as a percentage of the respective adult control, were: F19 - 38percent; N1 - 39percent; N12 - 8percent; N24 - 89percent; N34 - 166percent; and N45 - 118percent.A good correlation was found between histochemical staining for 3β-HSD and the quantitative method employed.Using (3H)-DHA as a substrate, LC isolated from F19, N1 and N12 produced testosterone in appreciable amounts (41percent, 55percent and 20percent of the total products respectively) whereas at advanced stages of development (N24 to adulthood) the major product was androstenedione (93 +/- 1percent).These findings may be explained by the observed decrease in 17β-hydroxysteroid dehydrogenase (17β-HSD) activity, due to an insufficient supply of NADPH, in the older vs. earlier stages of development.This study indicates the presence of steroidogenic enzymatic activity in LC throughout development in the rat.It also provides a relatively simple in vitro model for studies of testicular regulation during development.
- Paz, Gedalia F.,Winter, Jeremy S. D.,Reyes, Francisco I.,Faiman, Charles
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- ANDROSTENEDIONE AND TESTOSTERONE BIOSYNTHESIS BY THE ANDRENAL CORTEX OF THE HORSE
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An homogenate from cortical tissue of mare adrenals was incubated in the presence of tritiated pregnenolone.The (3H) androstenedione and the (3H) testosterone synthesized during the incubation were extracted, purified, and co-crystallized to constant specific activity in the presence of unlabeled carriers.The rate of conversion of pregnenolone to androstenedione and testosterone was of the order of 5 and 0.15 per cent respectively.The high ratio of (3H) androstenedione to (3H) testosterone observed in this study suggests that androstenedione is the main androgen produced by mare adrenals.It is concluded that adrenals could contribute to the production of blood androgens in normal as well as hyperandrogenic mares.
- Silberzahn, Pierre,Rashed, Fakhri,Zwain, Ismail,Leymarie, Pierre
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- The aging Leydig cell: 2. Two distinct populations of Leydig cells and the possible site of defective steroidogenesis
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Using metrizamide gradient centrifugation two populations of Leydig cells were found in both 60-90 day old and 24 month old rats. Cells from both Band 2 (B2) and Band 3 (B3) responded to LH stimulation with increased cyclic AMP formation; however, only B3 cells produced significant amounts of testosterone. Cells from both B2 and B3 of the old rats synthesized less cyclic AMP and testosterone than cells from their younger counterparts. In response to LH stimulation, 0.01 - 1.0 mIU/ml, no appreciable difference of cyclic AMP formation could be detected between young and old Leydig cells. Maximal testosterone production occurred when 1 mIU/ml LH was used. Only when LH concentration was increased to 10 and 100 mIU/ml, did young Leydig cells produce significantly more cyclic AMP than old Leydig cells. After addition of 5 x 10-7M of pregnenolone or progesterone to the incubation medium both young and old Leydig cells produced comparable amounts of testosterone. These results demonstrate no impairment of old rat Leydig cells to synthesize testosterone from pregnenolone and progesterone.
- Chen,Lin,Murono,Osterman,Cole,Nankin
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- One-Step Chemo-, Regio- and Stereoselective Reduction of Ketosteroids to Hydroxysteroids over Zr-Containing MOF-808 Metal-Organic Frameworks
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Zr-containing MOF-808 is a very promising heterogeneous catalyst for the selective reduction of ketosteroids to the corresponding hydroxysteroids through a Meerwein-Ponndorf-Verley (MPV) reaction. Interestingly, the process leads to the diastereoselective synthesis of elusive 17α-hydroxy derivatives in one step, whereas most chemical and biological transformations produce the 17β-OH compounds, or they require several additional steps to convert 17β-OH into 17α-OH by inverting the configuration of the 17 center. Moreover, MOF-808 is found to be stable and reusable; it is also chemoselective (only keto groups are reduced, even in the presence of other reducible groups such as C=C bonds) and regioselective (in 3,17-diketosteroids only the keto group in position 17 is reduced, while the 3-keto group remains almost intact). The kinetic rate constant and thermodynamic parameters of estrone reduction to estradiol have been obtained by a detailed temperature-dependent kinetic analysis. The results evidence a major contribution of the entropic term, thus suggesting that the diastereoselectivity of the process is controlled by the confinement of the reaction inside the MOF cavities, where the Zr4+ active sites are located.
- Llabrés i Xamena, F. X.,Mautschke, H.-H.
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p. 10766 - 10775
(2021/06/15)
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- Synthesis method of alkyl acid testosterone
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The invention discloses a synthesis method of alkyl acid testosterone, and belongs to the technical field of synthesis and processing of medicines. The method comprises the following steps of: taking4-androstenedione (4AD) as an initial raw material, firstly, carrying out enol ether protection on the keto group at the site 3, and reducing carbonyl at the site 17 into hydroxyl; or taking 4-androstenedione (4AD) as an initial raw material, firstly carrying out enol ether protection on the keto group at the site 3, then reducing carbonyl at the site 17 into hydroxyl, then carrying out hydrolysison the site 3 to obtain testosterone, and carrying out esterification and third-site hydrolysis to obtain the testosterone ester after testosterone third-site ketal protection. According to the method disclosed by the invention, the third site is protected during esterification reaction, the generation of impurities can be reduced, and an esterification reaction solvent is a water-insoluble organic solvent, so that after the reaction is completed, products can be directly extracted in a layered manner, a large amount of water does not need to be added to separate out the products, the amountof wastewater is reduced, the solvent can be recycled, and the process is more suitable for industrial production.
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- Microbial transformation of androstenedione by Cladosporium sphaerospermum and Ulocladium chartarum
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In this work, incubations of androstenedione 1 with Cladosporium sphaerospermum MRC 70266 and Ulocladium chartarum MRC 72584 have been reported. C. sphaerospermum MRC 70266 mainly hydroxylated 1 at C-6β, accompanied by a hydroxylation at C-15α, a reduction at C-17, a 5α-reduction and oxidations at C-6 and C-16 following hydroxylations. U. chartarum MRC 72584 hydroxylated 1 at C-6β, C-7α, C-7β and C-14α, accompanied by an oxidation at C-6 following its hydroxylation, a reduction at C-17 and a 5α-reduction. 6β,17β-Dihydroxyandrost-4-en-3,16-dione 8, one of the metabolites from the incubation of 1 with C. sphaerospermum MRC 70266, was determined as a new compound.
- Yildirim, Kudret,Kuru, Ali,Kü?ükba?ol, Eda
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- Regio- and stereoselective reduction of 17-oxosteroids to 17β-hydroxysteroids by a yeast strain Zygowilliopsis sp. WY7905
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The reduction of 17-oxosteroids to 17β-hydroxysteroids is one of the important transformations for the preparation of many steroidal drugs and intermediates. The strain Zygowilliopsis sp. WY7905 was found to catalyze the reduction of C-17 carbonyl group of androst-4-ene-3,17-dione (AD) to give testosterone (TS) as the sole product by the constitutive 17β-hydroxysteroid dehydrogenase (17β-HSD). The optimal conditions for the reduction were pH 8.0 and 30 °C with supplementing 10 g/l glucose and 1% Tween 80 (w/v). Under the optimized transformation conditions, 0.75 g/l AD was reduced to a single product TS with >90% yield and >99% diastereomeric excess (de) within 24 h. This strain also reduced other 17-oxosteroids such as estrone, 3β-hydroxyandrost-5-en-17-one and norandrostenedione, to give the corresponding 17β-hydroxysteroids, while the C-3 and C-20 carbonyl groups were intact. The absence of by-products in this microbial 17β-reduction would facilitate the product purification. As such, the strain might serve as a useful biocatalyst for this important transformation.
- Liu, Yuanyuan,Wang, Yu,Chen, Xi,Wu, Qiaqing,Wang, Min,Zhu, Dunming,Ma, Yanhe
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- PROCESS FOR PREPARATION OF TESTOSTERONE
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The present invention relates to a process for purification of 4-androsten-3,17-dione (II) and its conversion to testosterone (I) having purity > 99 % as measured by HPLC.
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- Testosterone preparation method
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Provided is a testosterone preparation method. The method uses androstenedione (also known as 4AD) as the raw material and comprises the following steps: A, synthesizing imidazoleethylamine which is to mix the 4AD and triethyl orthoformate with higher alcohol organic solution for acid catalysis to obtain 3beta Ethoxy-androsta 3,5-diene 17-ketone; B, synthesizing reducing substance, mixing the imidazoleethylamine with organic solution, adding metal borohydride to reduce the 17 ketone to 3beta Ethoxy-androsta 3,5-diene 17-alcohol; C, synthesizing testosterone, mixing the aforementioned reducing substance with organic solution, hydrolyzing with water, conducting post-treatment to acquire the testosterone crude which is mixed with low carbon alcohol to be decolored by active carbon and recrystallized, obtaining the final product of testosterone. The overall recovery rate of synthesized weight is 70%-75%. The method has the advantages of widely available material sources, simple operation, high yield rate, high purity, extreme reduction of costs, high recovery rate of solution in the reaction and processing, cost effectiveness and environmental protection.
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- NEW ENZYMATIC PROCESS FOR THE PREPARATION OF TESTOSTERONE AND ESTERS THEREOF
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The present invention relates to a new process for the preparation of testosterone by means of enzymatic hydrolysis of testosterone esters.
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Paragraph 0139
(2017/02/28)
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- NANOEMULSIONS HAVING REVERSIBLE CONTINUOUS AND DISPERSED PHASES
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A nanoemulsion having reversible continuous and dispersed phases. The nanoemulsion includes an aqueous phase and an oil phase, a weight ratio of the aqueous phase to the oil phase being 1:40-100:1. In the nanoemulsion, the aqueous phase is dispersed as nanosized droplets in the oil phase or the oil phase is dispersed as nanosized droplets in the aqueous phase. The aqueous phase contains water or a water solution and a water-soluble organic nanostructure stabilizer. The oil phase contains an oil or an oil solution, an organic gel thickener, and a hydrophilic surfactant having a hydrophilic-lipophilic balance value greater than 8.0. Also disclosed is a method for preparing the above-described nanoemulsion.
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- Biotransformation of androst-4-ene-3,17-dione by some fungi
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The incubations of androst-4-ene-3,17-dione with Aspergillus candidus MRC 200634, Aspergillus tamarii MRC 72400, Aspergillus wentii MRC 200316 and Mucor hiemalis MRC 70325 for 5 days are reported. A. candidus MRC 200634 mainly hydroxylated androst-4-ene-3,17-dione at C-11α, C-15α and C-15β whilst A. wentii MRC 200316 hydroxylated it mainly at C-6β. A. tamarii MRC 72400 showed predominately a Baeyer–Villiger monooxygenase activity. M. hiemalis MRC 70325 hydroxylated the substrate at C-14α and reduced most of it at C-17.
- Yildirim, Kudret,Kuru, Ali,Keskin, Ece,Salihoglu, Aylin,Bukum, Neslihan
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p. 594 - 597
(2017/11/14)
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- In a 4-androstenedione one-step synthesis method of testosterone (by machine translation)
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The present invention provides a 4-androstenedione one-step synthesis of testoserone method, which is characterized by comprising: step 1, the dissolved in androstenedione 5-15 times (weight ratio) in the mixed solvent system, cooling to -10 ° C the following; step 2, will be dissolved in potassium borohydride 8-15 times (weight ratio) in the pure water of; step 3, step 2 is added to a solution of 5-15 times (weight ratio) step 1 the, -5 ° C to -10 ° C in the feed liquid; step 4, in the -5 ° C to -10 ° C to react under the condition of androstenedione the reaction is complete, add weight to the potassium hydride states the boron 15-40% of glacial acetic acid, in order to destroy the excess also, then pressure reducing and recovering the solvent, water, filtering, crude; step 5, crude product recrystallized with ethanol to obtain testoserone works. (by machine translation)
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Paragraph 0024-0031
(2017/04/11)
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- Microbial transformation of androst-4-ene-3,17-dione by three fungal species Absidia griseolla var. igachii, Circinella muscae and Trichoderma virens
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Microbial transformation of androst-4-ene-3,17-dione (AD;I) by three fungal species including Absidia griseolla var. igachii, Circinella muscae and Trichoderma virens was investigated for the first time. While A. griseolla and C. muscae carried out hydroxylation reactions, the third fungi performed reduction of the 17-carbonyl group in a chemoselective manner. Incubation of AD by A. griseolla yielded four metabolites 6β- (II), 7α- (III), 7β- (VI) and 14α-hydroxy-AD (V), among which 6β-hydroxy-AD (II) was identified as the major product. Furthermore, the metabolites produced during AD biotransformation by C. muscae were 6β- (II), 7β- (III) and 14α-hydroxy-AD (V). On the other hand, T. virens remarkably reduced AD into testosterone (VI) as the only product with 60% yield. These metabolites were purified by TLC and identified by 1H NMR, 13C NMR and other spectroscopic data.
- Heidary, Marjan,Habibi, Zohreh
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- Preparation method of testosterone propionate intermediate 17 beta-hydroxyandrost-4-en-3-one
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The invention provides a preparation method of testosterone propionate intermediate 17 beta-hydroxyandrost-4-en-3-one (testosterone). With 4-androstenedione as the raw material, a 3-keto protection reaction, a 17-keto reduction reaction and a 3-keto deprotection reaction are sequentially conducted to prepare testosterone propionate intermediate 17 beta-hydroxyandrost-4-en-3-one (testosterone). The technology has the advantages that reaction selectivity is high, operation is easy and convenient, industrialization is easy to achieve, the production cost is low, and the yield is high.
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- Biotransformation of dehydro-epi-androsterone by Aspergillus parasiticus: Metabolic evidences of BVMO activity
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The research on the synthesis of steroids and its derivatives is of high interest due to their clinical applications. A particular focus is given to molecules bearing a D-ring lactone like testolactone because of its bioactivity. The Aspergillus genus has been used to perform steroid biotransformations since it offers a toolbox of redox enzymes. In this work, the use of growing cells of Aspergillus parasiticus to study the bioconversion of dehydro-epi-androsterone (DHEA) is described, emphasizing the metabolic steps leading to D-ring lactonization products. It was observed that A. parasiticus is not only capable of transforming bicyclo[3.2.0]hept-2-en-6-one, the standard Baeyer-Villiger monooxygenase (BVMO) substrate, but also yielded testololactone and the homo-lactone 3β-hydroxy-17a-oxa-d-homoandrost-5-en-17-one from DHEA. Moreover, the biocatalyst degraded the lateral chain of cortisone by an oxidative route suggesting the action of a BVMO, thus providing enough metabolic evidences denoting the presence of BVMO activity in A. parasiticus. Furthermore, since excellent biotransformation rates were observed, A. parasiticus is a promising candidate for the production of bioactive lactone-based compounds of steroidal origin in larger scales.
- Mascotti, M. Laura,Palazzolo, Martín A.,Bisogno, Fabricio R.,Kurina-Sanz, Marcela
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- Selective reduction of 4,6- conjugate diene -3-one steroid compound method
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Belonging to the field of chemical pharmacy, the invention relates to a method for selective reduction of 4, 6-conjugated diene-3-one steroid, and solves the problem of low yield in hydrogen reduction. The method mainly includes the steps of: 1) adding the 4, 6-conjugated diene-3-one steroid, a liquid solvent, a catalyst, and a reducing agent hydrogen donor into a reaction kettle, performing nitrogen protection, and carrying out stirring heating till reflux; 2) carry out reflux reaction for 3-10h; 3) at the end of reaction, filtering out the catalyst; 4) distilling the solvent; 5) adding purified water after distillation; and 6) conducting cooling, pumping filtering, washing and drying to obtain a 4-ene-3-steroid crystal.
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Paragraph 0058-0065
(2019/11/21)
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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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- Linking of Alcohols with Vinyl Azides
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A protocol to link alcohols with vinyl azides has been established through fluoro- or bromo-alkoxylation of vinyl azides to provide α-alkoxy-β-haloalkyl azides. A series of primary and secondary alcohols including natural products and their derivatives such as sugars and steroids were successfully anchored with vinyl azides. The as-prepared cyanine dye linked testosterones were capable of rapid cell membrane imaging in real time.
- Wang, Yi-Feng,Hu, Ming,Hayashi, Hirohito,Xing, Bengang,Chiba, Shunsuke
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supporting information
p. 992 - 995
(2016/03/15)
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- The generation of a steroid library using filamentous fungi immobilized in calcium alginate Dedicated to the memory of Professor Sir John W. Cornforth, University of Sussex (1917-2013).
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Four fungi, namely, Rhizopus oryzae ATCC 11145, Mucor plumbeus ATCC 4740, Cunninghamella echinulata var. elegans ATCC 8688a, and Whetzelinia sclerotiorum ATCC 18687, were subjected to entrapment in calcium alginate, and the beads derived were used in the biotransformation of the steroids 3β,17β-dihydroxyandrost-5-ene (1) and 17β-hydroxyandrost-4-en-3-one (2). Incubations performed utilized beads from two different encapsulated fungi to explore their potential for the production of metabolites other than those derived from the individual fungi. The investigation showed that steroids from both single and crossover transformations were typically produced, some of which were hitherto unreported. The results indicated that this general technique can be exploited for the production of small libraries of compounds.
- Peart, Patrice C.,Reynolds, William F.,Reese, Paul B.
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- Aldo-keto Reductase 1B15 (AKR1B15): A mitochondrial human aldo-keto reductase with activity toward steroids and 3-keto-acyl-CoA conjugates
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Alto-keto reductases (AKRs) comprise a superfamily of proteins involved in the reduction and oxidation of biogenic and xenobiotic carbonyls. In humans, at least 15 AKR superfamily members have been identified so far. One of these is a newly identified gene locus, AKR1B15, which clusters on chromosome 7 with the other human AKR1B subfamily members (i.e. AKR1B1 and AKR1B10). We show that alternative splicing of the AKR1B15 gene transcript gives rise to two protein isoforms with different N termini: AKR1B15.1 is a 316-amino acid protein with 91% amino acid identity to AKR1B10; AKR1B15.2 has a prolonged N terminus and consists of 344 amino acid residues. The two gene products differ in their expression level, subcellular localization, and activity. In contrast with other AKR enzymes, which are mostly cytosolic, AKR1B15.1 co-localizes with the mitochondria. Kinetic studies show that AKR1B15.1 is predominantly a reductive enzyme that catalyzes the reduction of androgens and estrogens with high positional selectivity (17β-hydroxysteroid dehydrogenase activity) as well as 3-ketoacyl-CoA conjugates and exhibits strong cofactor selectivity toward NADP(H). In accordance with its substrate spectrum, the enzyme is expressed at the highest levels in steroid-sensitive tissues, namely placenta, testis, and adipose tissue. Placental and adipose expression could be reproduced in the BeWo and SGBS cell lines, respectively. In contrast, AKR1B15.2 localizes to the cytosol and displays no enzymatic activity with the substrates tested. Collectively, these results demonstrate the existence of a novel catalytically active AKR, which is associated with mitochondria and expressed mainly in steroid-sensitive tissues.
- Weber, Susanne,Salabei, Joshua K.,M?ller, Gabriele,Kremmer, Elisabeth,Bhatnagar, Aruni,Adamski, Jerzy,Barski, Oleg A.
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p. 6531 - 6545
(2015/03/30)
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- Selective oxidation of benzylic, allylic and propargylic alcohols using dirhodium(II) tetraamidinate as catalyst and aqueous tert-butyl hydroperoxide as oxidant
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We show that the dirhodium(II) tetraamidinate complex Rh2(Msip)4 efficiently catalyzes the oxidation of activated secondary alcohols at only 0.1 mol% loading. In this approach, we oxidized various benzylic, allylic and propargylic alcohols to the corresponding carbonyl compounds under mild aqueous conditions using the inexpensive oxidant T-HYDRO (70 wt% aqueous tert-butyl hydroperoxide).
- Wusiman, Abudureheman,Lu, Chong-Dao
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p. 254 - 258
(2015/03/30)
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- Biotransformation of testosterone and testosterone heptanoate by four filamentous fungi
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The microbial transformations of testosterone and testosterone heptanoate by four fungi: Absidia griseolla var. igachii PTCC 5260, Acremonium chrysogenu PTCC 5271, Fusarium fujikuroi PTCC 5144, and Fusarium solani complex PTCC 5285 were investigated for the first time. Incubation of testosterone heptanoate with F. fujikuroi and F. solani yielded three metabolites, which were isolated and characterized as testosterone, androst-4-ene-3,17-dione, and 6β-hydroxy testosterone. 6β-Hydroxy testosterone was the major metabolite obtained from testosterone heptanoate biotransformation by two fungal species. A. griseolla and A. chrysogenu produced 14α-hydroxy testosterone as major metabolite, together with testosterone and 6β-hydroxy testosterone in lower yields. The biotransformation of testosterone by F. fujikuroi and A. griseolla was also investigated in order to examine the influence of the ester group on the course of transformation. Androst-4-ene-3,17-dione was only identified in the biotransformation of testosterone by F. fujikuroi. The same product was observed in incubation of testosterone by A. griseolla, together with 14α-hydroxy testosterone in very low yield. Furthermore, time course study was also carried out in order to examine the formation of metabolites as a function of time, which was determined by HPLC. The structures of compounds were determined by their comprehensive spectroscopic analysis and comparison with literature data.
- Ghasemi, Sabrieh,Mohajeri, Maryam,Habibi, Zohreh
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supporting information
p. 7 - 12
(2014/12/11)
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- Biotransformations of steroids to testololactone by a multifunctional strain Penicillium simplicissimum WY134-2
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The biotransformations of a range of steroidal compounds, including 17α-hydroxy progesterone, progesterone, testosterone, androst-4-ene-3,17- dione (AD), pregnenolone, and dehydroepiandrosterone (DHEA), by Penicillium simplicissimum WY134-2 have been investigated. In all the cases, testolic acid and testololactone were detected, and the acid was converted to the lactone when pH was adjusted to 1, leading to isolation of testololactone in 25%-96% yields. Especially for progesterone and testosterone, the isolated yields were 93% and 96% with substrate concentration being 3 g/L, suggesting that P. simplicissimum WY134-2 may be used for the synthesis of testololactone. The results revealed the multi-functional catalytic activity of P. simplicissimum WY134-2 toward steroids for the first time. The possible reaction pathways of steroids promoted by this strain were discussed.
- Yang, Beibei,Wang, Yu,Chen, Xi,Feng, Jinhui,Wu, Qiaqing,Zhu, Dunming,Ma, Yanhe
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- Substrate specificity and inhibitor sensitivity of rabbit 20α-hydroxysteroid dehydrogenase
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In this study, we examined the substrate specificity and inhibitor sensitivity of rabbit 20α-hydroxysteroid dehydrogenase (AKR1C5), which plays a role in the termination of pregnancy by progesterone inactivation. AKR1C5 moderately reduced the 3-keto group of only 5α-dihydrosteroids with 17β- or 20α/β-hydroxy group among 3-ketosteroids. In contrast, the enzyme reversibly and efficiently catalyzed the reduction of various 17- and 20-ketosteroids, including estrogen precursors (dehydroepiandrosterone, estrone and 5α-androstan-3β- ol-17-one) and tocolytic 5β-pregnane-3,20- dione. In addition to the progesterone inactivation, the formation of estrogens and metabolism of the tocolytic steroid by AKR1C5 may be related to its role in rabbit parturition. AKR1C5 also reduced various non-steroidal carbonyl compounds, including isatin, an antagonist of the C-type natriuretic peptide receptor, and 4-oxo-2-nonenal, suggesting its roles in controlling the bioactive isatin and detoxification of cytotoxic aldehydes. AKR1C5 was potently and competitively inhibited by flavonoids such as kaempferol and quercetin, suggesting that its activity is affected by ingested flavonoids.
- Endo, Satoshi,Arai, Yuki,Hara, Akira,Kitade, Yukio,Bunai, Yasuo,El-Kabbani, Ossama,Matsunaga, Toshiyuki
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p. 1514 - 1518
(2013/10/08)
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- Rabbit 3-hydroxyhexobarbital dehydrogenase is a NADPH-preferring reductase with broad substrate specificity for ketosteroids, prostaglandin D2, and other endogenous and xenobiotic carbonyl compounds
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3-Hydroxyhexobarbital dehydrogenase (3HBD) catalyzes NAD(P) +-linked oxidation of 3-hydroxyhexobarbital into 3-oxohexobarbital. The enzyme has been thought to act as a dehydrogenase for xenobiotic alcohols and some hydroxysteroids, but its physiological function remains unknown. We have purified rabbit 3HBD, isolated its cDNA, and examined its specificity for coenzymes and substrates, reaction directionality and tissue distribution. 3HBD is a member (AKR1C29) of the aldo-keto reductase (AKR) superfamily, and exhibited high preference for NADP(H) over NAD(H) at a physiological pH of 7.4. In the NADPH-linked reduction, 3HBD showed broad substrate specificity for a variety of quinones, ketones and aldehydes, including 3-, 17- and 20-ketosteroids and prostaglandin D2, which were converted to 3α-, 17β- and 20α-hydroxysteroids and 9α,11β- prostaglandin F2, respectively. Especially, α-diketones (such as isatin and diacetyl) and lipid peroxidation-derived aldehydes (such as 4-oxo- and 4-hydroxy-2-nonenals) were excellent substrates showing low Km values (0.1-5.9 μM). In 3HBD-overexpressed cells, 3-oxohexobarbital and 5β-androstan-3α-ol-17-one were metabolized into 3-hydroxyhexobarbital and 5β-androstane-3α,17β-diol, respectively, but the reverse reactions did not proceed. The overexpression of the enzyme in the cells decreased the cytotoxicity of 4-oxo-2-nonenal. The mRNA for 3HBD was ubiquitously expressed in rabbit tissues. The results suggest that 3HBD is an NADPH-preferring reductase, and plays roles in the metabolisms of steroids, prostaglandin D2, carbohydrates and xenobiotics, as well as a defense system, protecting against reactive carbonyl compounds.
- Endo, Satoshi,Matsunaga, Toshiyuki,Matsumoto, Atsuko,Arai, Yuki,Ohno, Satoshi,El-Kabbani, Ossama,Tajima, Kazuo,Bunai, Yasuo,Yamano, Shigeru,Hara, Akira,Kitade, Yukio
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p. 1366 - 1375
(2013/11/19)
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- Aniline-terephthalaldehyde resin p-toluenesulfonic acid (ATRT) salt as efficient mild polymeric solid acid catalyst
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Aniline-terephthalaldehyde resin p-toluenesulfonic acid (ATRT) salt was easily prepared by the reaction of aniline with 1.25 equiv of terephthalaldehyde in the presence of 1.0 equiv of p-toluenesulfonic acid at 75 C for 24 h in EtOH. ATRT efficiently catalyzed the tetrahydropyranylation of alcohols and deprotection of tetrahydropyranyl (THP), triethylsilyl (TES), and tert-butyldimethylsilyl (TBDMS) ethers. Deprotection of dodecyl THP ether and dodecyl TBDMS ether catalyzed by ATRT proceeded faster than those by pyridinium p-toluenesulfonate (PPTS). ATRT was reused without significant loss of activities.
- Tanemura, Kiyoshi,Suzuki, Tsuneo
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supporting information
p. 6740 - 6743
(2013/11/19)
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- Chemoselective oxidation by electronically tuned nitroxyl radical catalysts
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Electronic tuning: Nitroxyl radical 1 is shown to be an efficient catalyst for the oxidation of secondary alcohols, and promotes oxidation through an oxoammonium species which is highly reactive because of the adjacent electron-withdrawing ester groups. Chemoselective oxidation of benzylic alcohols in the presence of aliphatic alcohols is observed and is proposed to proceed by a rate-determining hydride transfer. Copyright
- Hamada, Shohei,Furuta, Takumi,Wada, Yoshiyuki,Kawabata, Takeo
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supporting information
p. 8093 - 8097
(2013/08/23)
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- Baeyer-villiger oxidation of some steroids by Aspergillus tamarii MRC 72400
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Biotransformations of epiandrosterone (1), dehydroepiandrosterone (2), testosterone (3), progesterone (4) and pregnenolone (5) by Aspergillus tamarii MRC 72400 for 5 days have been reported and the results of these incubations have been compared with previously published data obtained with Aspergillus tamarii QM 1223. A. tamarii MRC 72400 showed higher Bayer-Villiger monooxygenase activities than A. tamarii QM 1223 did. Apart from pregnenolone (5), A. tamarii MRC 72400 metabolized these steroids in different ways. Incubation of epiandrosterone (1) afforded 3β,11β-dihydroxy-5α-androstan-17- one (6) (3%) and 3β-hydroxy-17a-oxa-D-homo-5α-androstan-17-one (7) (9.5%). Incubation of dehydroepiandrosterone (2) afforded 3β-hydroxy-17a- oxa-D-homoandrost-5-en-17-one (8) (28%), testolactone (9) (6%), 3β,7β-dihydroxyandrost-5-en-17-one (10) (13%) and 3β,7α- dihydroxyandrost- 5-en-17-one (11) (24%). Incubation of testosterone (3) afforded testolactone (9) (58%). Incubation of progesterone (4) also afforded testolactone (9), however in higher yield (86%). Incubation of pregnenolone (5) afforded 3β-hydroxy-17a-oxa-D-homoandrost- 5-en-17-one (8) (25%) and testolactone (9) (27%).
- Yildirim, Kudret,Uzuner, Ahmet,Gulcuoglu, Emine Yasemin
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scheme or table
p. 743 - 754
(2011/12/03)
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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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- Studies on Baeyer-Villiger oxidation of steroids: DHEA and pregnenolone d-lactonization pathways in Penicillium camemberti AM83
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Penicillium camemberti AM83 strain is able to carry out effective Baeyer-Villiger type oxidation of DHEA, pregnenolone, androstenedione and progesterone to testololactone. Pregnenolone and DHEA underwent oxidation to testololactone via two routes: through
- Kolek, Teresa,Szpineter, Anna,Swizdor, Alina
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scheme or table
p. 859 - 862
(2009/12/01)
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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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- 2-(Prenyloxymethyl)benzoyl (POMB) group: a new temporary protecting group removable by intramolecular cyclization
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2-(Prenyloxymethyl)benzoates can be prepared from alcohols and readily available 2-(prenyloxymethyl)benzoic acid by standard acylation techniques or by Mitsunobu reaction with inversion of configuration. The POMB group can be cleaved first by oxidative removal of the prenyl group with DDQ followed by lactonization with expulsion of the alcohol catalyzed by Yb(OTf)3. These reaction conditions are compatible with the presence of a large number of common protecting groups.
- Vatèle, Jean-Michel
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p. 10921 - 10929
(2008/02/12)
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- Microbial transformation of androst-4-ene-3,17-dione by Beauveria bassiana
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The microbial transformation of androst-4-ene-3,17-dione (I) by the fungus Beauveria bassiana CCTCC AF206001 has been investigated using pH 6.0 and 7.0 media. Two hydroxylated metabolites were obtained with the pH 6.0 medium. The major product was 11α-hydroxyandrost-4-ene-3,17-dione (II) whereas the minor product was 6β,11α-dihydroxyandrost-4-ene-3,17-dione (III). On the other hand, four hydroxylated and/or reduced metabolites were obtained with the pH 7.0 medium. The major product was 11α,17β-dihydroxyandrost-ene-3-one (V) and the minor products were 17β-hydroxyandrost-ene-3-one (IV), 6β,11α,17β-trihydroxyandrost-ene-3-one (VI) and 3α,11α,17β-trihydroxy-5α-androstane (VII). The products were purified by chromatographic methods, and were identified on the basis of spectroscopic methods. This fungus strain is clearly an efficient biocatalyst for 11α-hydroxylation and reduction of the 17-carbonyl group.
- Xiong, Zhigang,Wei, Qi,Chen, Hanmei,Chen, Shouwen,Xu, Wenjin,Qiu, Guofu,Liang, Shucai,Hu, Xianming
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p. 979 - 983
(2007/10/03)
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- Nitrobenzene as hydrogen acceptor in Pd/C-catalyzed hydrogen transfer reaction
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Nitrobenzene was found to work as an efficient hydrogen acceptor in the oxidation of allylic alcohols to give the corresponding enones in high yields.
- Tanaka, Takanori,Kawabata, Hirotoshi,Hayashi, Masahiko
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p. 4989 - 4991
(2007/10/03)
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- 2-(Prenyloxymethyl)benzoyl (POMB) as a new temporary protecting group for alcohols
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The 2-(prenyloxymethyl)benzoyl (POMB) group was introduced in high yields to hydroxyl functions using the crystalline reagent, 2-(prenyloxymethyl)benzoic acid, in the presence of dicyclohexylcarbodiimide (DCC) and 4- dimethylaminopyridine (DMAP). 2-(Prenyloxymethyl)benzoic acid is readily available, in two steps, from phthalide in 65% overall yield. The POMB group can be cleaved, in two steps, by treatment with 2,3-dichloro-5,6-dicyanoquinone (DDQ) followed by intramolecular lactonisation of the resulting hydroxy ester induced by a catalytic amount of Yb(OTf)3·H2O. The reaction conditions are compatible with the presence of a number of protecting groups such as isopropylidene, benzyl, acetyl, chloroacetyl, benzoyl, levulinoyl, Fmoc and Boc groups.
- Vatèle, Jean-Michel
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p. 2299 - 2301
(2007/10/03)
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- A new method for the selective oxidation of allylic and benzylic alcohols
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A new method is described for the selective oxidation of allylic or benzylic alcohols, in the presence of saturated alcohols, using trimethylamine-N-oxide in the presence of an iron carbonyl.
- Pearson, Anthony J.,Kwak, Yoonhyun
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p. 5417 - 5419
(2007/10/03)
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- 17-Beta-hydroxysteroid dehydrogenase-II inhibitors
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17-beta-hydroxysteroid dehydrogenase-I1 inhibitors having the structural formula wherein the phenyl group labeled A and the group —C(R4)(R6)Y are oriented cis to each other; W represents 0 or S; R1 represents —H or optionally substituted —(C1-C4)alkyl; n represents 0 or an integer of 1-3; and R2 represents any of a variety of substituents on ring A. R4 generally represents —H but may be a bond terminating at the ortho position of ring A. Y represents fluorine, —OR5, or —SR5, and R5 represents —H. optionally substituted —(C1-C4)alkyl, optionally substituted -phenyl, optionally substituted —(C1-C4)alkyl-phenyl, or optionally substituted —(C1-C4)acyl. R6 represents any of a variety of groups as defined in the specification and claims, including heteroaryl, arylalkyl, heteroarylalkyl, arylalkenyl, heteroarylalkenyl, alkynyl, arylalkynyl, heteroarylalkynyl, aryl, and indolyl. Pharmaceutically acceptable salts and N-oxides of these materials are also included. Also claimed are pharmaceutical compositions containing these materials and methods of using them.
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- Method of treating acne
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A method of treating inflammatory skin diseases and/or hair loss, comprising administering to a patient in need of such treatment a therapeutically effective amount of a leukotriene receptor antagonist, an antihistamine, or other anti-inflammatory drug, preferably at least twice a day, preferably for at least two months.
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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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- An efficient and chemoselective cleavage of prenyl ethers with DDQ
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The prenyl (Pre) protecting group tor hydroxyl functions is readily removed at room temperature with DDQ in dichloromethane-water (9:1). The reaction conditions are compatible with the presence of other ethereal functionalities such as acetonides, allyl, benzyl, TBS, TBDPS groups. We have also shown that Sdeprotection of prenyl ethers using a catalytic amount of DDQ in the presence of 3 equivalents of Mn(OAc)3 is a good alternative for the use of a stoichiometric amount of DDQ, albeit the reaction time being longer.
- Vatéle, Jean-Michel
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p. 507 - 509
(2007/10/03)
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- The prenyl group: A versatile hydroxy protecting group, removable chemoselectively under mild conditions
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Iodine in dichloromethane (in the presence of 3? molecular sieves for acid-sensitive substrates) and 2,3-dichloro-5,6-dicyanoquinone (DDQ) in dichloromethane-water (9:1) are mild and efficient methods to cleave prenyl ethers. These reaction conditions are compatible with the presence of other protecting groups such as acetals, acetates, allyl, benzyl and TBDPS groups. Exposure of aryl prenyl ethers to iodine led to the formation of 3-iodo-2,2-dimethylchroman derivatives in acceptable yields via a tandem Friedel-Crafts/iodocyclization reactions. Facile one-step transformation of two iodinated dimethylchroman derivatives allowed the synthesis of natural flavanoids among them: zanthoxylol, an anti-sickling agent.
- Vatèle, Jean-Michel
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p. 5689 - 5698
(2007/10/03)
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- Penetration enhancing and irritation reducing systems
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This invention lies in the technology of transdermal and topical drug delivery. In particular, the present invention relates to enhancement of the penetration of transdermally or topically applied drugs and with the reduction of skin irritation that often accompanies transdermal and topical drug delivery.
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- Smilagenin and its use
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The invention discloses the use of a smilagenin in the treatment of cognitive disfunction and similar conditions. Methods of treatment, and pharmaceutical compositions are also disclosed.
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- An easy deoxygenation of conjugated epoxides
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An easy and high yielding transformation of epoxyketones and phenyl substituted epoxides to trans olefins in a convergent diastereoselective process is reported. The method was applied to the selective C-25 hydroxy- functionalisation of 3-keio-Δ4-cholestan-3-one, a key intermediate for the synthesis of C-25 hydroxy vitamin D3. (C) 2000 Elsevier Science Ltd.
- Righi, Giuliana,Bovicelli, Paolo,Sperandio, Anna
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p. 1733 - 1737
(2007/10/03)
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- Transformation of steroidal cyclohexadienyl anion without fragmentation: Unexpected synthesis of methylenesteroid
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In contrast with androsta-1,4-diene-3α/β,17β-diol, its 3-O-methyl ether is transformed upon C(3)-deprotonation into the corresponding 3-methylene steroid with migration of the O-methyl group on the steroid skeleton (by the scheme of Wittig rearrangement) rather than eliminating the 19-methyl group.
- Vasil'eva,Lapitskaya,Pivnitsky
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p. 1380 - 1382
(2007/10/03)
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- The organoselenium-mediated reduction of α,β-epoxy ketones, α,β-epoxy esters, and their congeners to β-hydroxy carbonyl compounds: Novel methodologies for the synthesis of aldols and their analogues
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Novel methods for the reduction of α,β-epoxy ketones, α,β-epoxy esters (glycidic esters), and their congeners to β-hydroxy carbonyl compounds (aldols) by the use of organoselenium reagents are described. The reagents, a sodium phenylseleno(triethyl)borate complex Na[PhSeB(OEt)3] easily prepared by reduction of (PhSe)2 with NaBH4 in EtOH and benzeneselenol (PhSeH) generated in situ from the borate complex by addition of acetic acid, have been demonstrated to serve as excellent reducing agents for these transformations. The organoselenium-mediated reduction of α,β-epoxy carbonyl compounds regiospecifically occurs at the α-carbon to produce a wide variety of cyclic (intramolecular) aldols as well as acyclic (intermolecular) ones in excellent yields. Quantitative mechanistic studies have revealed that the organoselenium-mediated reduction proceeds via an α-substitution process in contrast to the common electron transfer reducing agents.
- Miyashita, Masaaki,Suzuki, Toshio,Hoshino, Masahide,Yoshikoshi, Akira
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p. 12469 - 12486
(2007/10/03)
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