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1.
Both the 5α, 6α- and 5β, 6β-dichloromethylene adducts (2a and 2b) of 3β-acetoxy-5-androsten-17-one (1) are produced when the latter is exposed to dichlorocarbene generated from chloroform and base by Phase Transfer Catalysis using ultrasound as a means of agitation. The 1H NMR substituent effects of 5α, 6α- and 5β, 6β-dichloromethylene on the angular methyl groups (Zürcher values) are given. The 13C NMR spectra for both compounds are presented and discussed.  相似文献   

2.
5α-Androstane-3α, 16α 17β-triol was synthesized from 3β-hy-droxy-5-androsten-17-one. The procedure Involved catalytic hydrogenation of 3β-hydroxy-5-androsten-17-one to 3β-hydroxy-5α-androstan-17-one. This was followed by conversion of the 3β-hydroxy group to 3α-benzoyloxy group by the Mitsunobu reaction. Further treatment with isopropenyl acetate yielded 5α-androsten-16-ene-3α, 17-diol 3-benzoate 17-acetate. This was then converted to 3α, 17-dihydroxy-5α-androstan-16-one 3-benzoate 17-acetate via the unstable epoxide intermediate after treatment with m-cloroperoxybenzoic acid. LiAlH4 reduction of this compound formed 5α-androstane-3α, 16α, 17β-trlol. 1H and 13C NMR of various steroids are presented to confirm the structure of this compound.  相似文献   

3.
The metabolic fate of the bile add analogs, 3α,7α-dihydroxy-7β-methyl-5β-cholanoic acid and 3α,7β-dihydroxy-7α-methyl-5β-cholanoic acid, was investigated and compared with that of chenodeoxycholic acid in hamsters. Both bile acid analogs were absorbed rapidly from the intestine and excreted into bile at similar to that of chenodeoxycholic acid. In the strain of hamster studied, the biliary bile were conjugated with both glycine and taurine. After continuous intravenous infusion, chenodeoxycholic acid the analogs became the major bile acid constituents in bile. After oral administration of a single dose of these compounds, fecal analysis revealed the existence of unchanged material (25–35%) as well as considerable amounts of metabolites (65–75%). The major metabolites excreted into feces were more polar than the starting material and were tentatively identified as trifaydroxy-7-methyl compounds by radioactive thin-layer chromatography. However, monohydroxy compounds were also found in the fecal extracts. These results show that chenodeoxycholic acid and ursodeoxycholic acid with a methyl group at the 7-position are resistant to bacterial 7-dehydroxylation than the normally occurring bile acids and that a certain proportion of these analogs is hydroxylated to give the corespondiag trihydroxy compound(s), In a control experiment, about 5% of administered chenodeoxychoulic acid was metabolized to a trihydroxy feile acid, but most of the compound (95%) was transformed into lithocholic acid.  相似文献   

4.
A single thin layer chromatography and three antibodies were used for the specific radioimmunoassay of four androgens in pooled rat plasma (Sprague-Dawley adult males). The following values were found (pg/ml ± SD). Testosterone : 3, 138 ± 173; dihydrotestosterone : 374 ± 20; 5α-androstane-3α 17β-diol : 284 ± 24; 5α-androstane-3β, 17β-diol : 223 ± 11.  相似文献   

5.
This study has identified the polar metabolites of 5α-androstane-3β, 17β-diol(3β-diol) produced by the canine prostate. The major metabolite is 5α-androstane-3β, 7α, 17β-triol (7α-triol) accounting for approximately 80% of the total polar metabolites of 3β-diol. The remaining 20% is accounted for exclusively by another triol, 5α-androstane-3β, 6α, 17β-triol(6α-triol). This study has also characterized two enzymatic hydroxylases responsible for respective triol formation: 5α-androstane-3β, 17β-diol 6α-hydroxylase (6α-hydroxylase) and 5α-androstane-3β, 17β-diol 7α-hydroxylase (7α-hydroxylase). Both of these irreversible hydroxylases are located in the particulate fraction of the prostate and can utilize either NADH or NADPH as cofactor. Several in vitro steroid inhibitors of these hydroxylases were identified including cholesterol, estradiol and diethylstilbestrol. Neither of the hydroxylases were found to be decreased by castration (3 months) when expressed as activity/DNA. Using a variety of C19 androstane substrates, 6α- and 7α-triol were found to be major components of the total 3β-hydroxy-5α-androstane metabolites produced by the canine prostate.  相似文献   

6.
A short and efficient method for the stereospecific synthesis of 3α,7α-dihydroxy-5β-androstan-17-one was accomplished from the readily available 4-androstene-3,17-dione. Key steps are the stereospecific and selective epoxidation of 4,6-androstadiene-3,17-dione, followed by hydrogenations with carefully selected reagents, solvents and reaction conditions.  相似文献   

7.
17β-Nandrolone (17β-NT) is one of the most frequently misused anabolic steroids in meat producing animals. As a result of its extensive metabolism combined with the possibility of interferences with other endogenous compounds, detection of its illegal use often turns out to be a difficult issue. In recent years, proving the illegal administration of 17β-NT became even more challenging since the presence of endogenous presence of 17β-NT or some of its metabolite in different species was demonstrated. In bovines, 17α-NT can occur naturally in the urine of pregnant cows and recent findings reported that both forms can be detected in injured animals. Because efficient control must both take into account metabolic patterns and associated kinetics of elimination, the purpose of the present study was to investigate further some estranediols (5α-estrane-3β,17β-diol (abb), 5β-estrane-3α,17β-diol (bab), 5α-estrane-3β,17α-diol (aba), 5α-estrane-3α,17β-diol (aab) and 5β-estrane-3α,17α-diol (baa)) as particular metabolites of 17β-NT on a large number of injured (n=65) or pregnant (n=40) bovines. Whereas the metabolites abb, bab, aba and baa have previously been detected in urine up to several days after 17β-NT administration, the present study showed that some of the isomers abb (5α-estrane-3β,17β-diol) and bab (5β-estrane-3α,17β-diol) could not be detected in injured or pregnant animals, even at very low levels. This result may open a new way for the screening of anabolic steroid administration considering these 2 estranediols as biomarkers to indicate nandrolone abuse in cattle.  相似文献   

8.
The syntheses of 15β-carboxyethylmercapto-5α-dihydrotestosterone, 15β-carboxy-ethylmercapto-5α-androstane-3β, 17β-diol and 15β-carboxyethylmercapto-5α-androstane-3α, 17β-diol and the preparation of their bovine serum albumin (BSA) conjugates are described. These conjugates were employed for the generation of specific antisera suitable for radioimmunoassay (RIA) of 5α-dihydrotestosterone (5α-DHT), 5α-androstane-3β, 17β-diol (3β3-diol) and 5α-androstane-3α, 17β-diol (3α-diol).  相似文献   

9.
The neutral urinary excretion products of 17β-hydroxy-2α,3α-cyclopropano-5α-androstane from the rabbit, dosed orally, were investigated. Column chromatography yielded five crystalline metabolites which were identified by GLC and spectroscopic measurements. Three of these substances were hydroxylated in the 4α-position and one in the 6a-position with the cyclopropane ring intact. The fifth substance, 17β-hydroxy-3β-methyl-5α-androstan-2-one, can be derived from initial hydroxylation of the cyclopropane ring at C-2 followed by ring opening. The dosed substance and triol material was shown to be present by GLC and m.s. measurements. GLC determinations show that hydroxylation has occurred at C-4?C-6>C-2.  相似文献   

10.
Cholesterol metabolism has been recently linked to cancer, highlighting the importance of the characterization of new metabolic pathways in the sterol series. One of these pathways is centered on cholesterol-5,6-epoxides (5,6-ECs). 5,6-ECs can either generate dendrogenin A, a tumor suppressor present in healthy mammalian tissues, or the carcinogenic cholestane-3β,5α,6β-triol (CT) and its putative metabolite 6-oxo-cholestan-3β,5α-diol (OCDO) in tumor cells. We are currently investigating the identification of the enzyme involved in OCDO biosynthesis, which would be highly facilitated by the use of commercially unavailable [14C]-cholestane-3β,5α,6β-triol and [14C]-6-oxo-cholestan-3β,5α-diol. In the present study we report the one-step synthesis of [14C]-cholestane-3β,5α,6β-triol and [14C]-6-oxo-cholestan-3β,5α-diol by oxidation of [14C]-cholesterol with iodide metaperiodate (HIO4).  相似文献   

11.
The inhibition of the mitochondrial hydroxylation of 5β-cholestane-3α, 7α, 12α-triol at the 26 position by a CO:O2 gas mixture was maximally reversed by monochromatic light at the wavelength of 450 nm. This establishes the involvement of a cytochrome P450 dependent monooxygenase in the 26-hydroxylation of 5β-cholestane-3α, 7α, 12α-triol in rat liver mitochondria.  相似文献   

12.
Oxysterols are oxidation products of cholesterol. Cholestane-3β, 5α, 6β-triol (abbreviated as triol) is one of the most abundant and active oxysterols. Here, we report that triol exhibits anti-cancer activity against human prostate cancer cells. Treatment of cells with triol dose-dependently suppressed proliferation of LNCaP CDXR-3, DU-145, and PC-3 human prostate cancer cells and reduced colony formation in soft agar. Oral administration of triol at 20 mg/kg daily for three weeks significantly retarded the growth of PC-3 xenografts in nude mice. Flow cytometric analysis revealed that triol treatment at 10–40 µM caused G1 cell cycle arrest while the TUNEL assay indicated that triol treatment at 20–40 µM induced apoptosis in all three cell lines. Micro-Western Arrays and traditional Western blotting methods indicated that triol treatment resulted in reduced expression of Akt1, phospho-Akt Ser473, phospho-Akt Thr308, PDK1, c-Myc, and Skp2 protein levels as well as accumulation of the cell cycle inhibitor p27Kip. Triol treatment also resulted in reduced Akt1 protein expression in PC-3 xenografts. Overexpression of Skp2 in PC-3 cells partially rescued the growth inhibition caused by triol. Triol treatment suppressed migration and invasion of DU-145, PC-3, and CDXR-3 cells. The expression levels of proteins associated with epithelial-mesenchymal transition as well as focal adhesion kinase were affected by triol treatment in these cells. Triol treatment caused increased expression of E-cadherin protein levels but decreased expression of N-cadherin, vimentin, Slug, FAK, phospho-FAK Ser722, and phospho-FAK Tyr861 protein levels. Confocal laser microscopy revealed redistribution of β-actin and α-tubulin at the periphery of the CDXR-3 and DU-145 cells. Our observations suggest that triol may represent a promising therapeutic agent for advanced metastatic prostate cancer.  相似文献   

13.
Anordrin, an antifertility agent that is an antiestrogen with weak estrogenic activity, has been studied to further characterize its hormonal activities. A dose of 2.0 μg/mouse·day for 7 days did not increase the uterine content of protein, but it did inhibit to a small extent the effect of administered estradiol-17β on uterine protein content and more significantly the effect of estradiol-17β on the uterine content of progesterone receptors. Anordrin also decreased serum corticosteroid-binding globulin levels. Administration of an average daily dose of 160 μg/day of anordrin to intact male mice had no effect on weights of kidney, testis, or seminal vesicle after 10 days, but seminal vesicle weight was significantly decreased after 30 days at a slightly lower dose. Similarly, anordrin inhibited the increase in seminal vesicle weight induced by testosterone propionate treatment of castrated mice. In female mice anordrin failed to maintain deciduomata and blocked the ability of progesterone (2.0 mg/mouse·day) to do so. However, anordrin did not compete with the androgen [3H]R1881 for binding in kidney cytosol or with the progestin [3H]R5020 for uterine receptor sites. Anordrin also did not compete with [3H]corticosterone for binding to serum proteins.  相似文献   

14.
Richmond V  Garrido Santos GA  Murray AP  Maier MS 《Steroids》2011,76(10-11):1160-1165
Disodium 2β,3α-dihydroxy-5α-cholestan-6-one disulfate (8) has been synthesized using cholesterol (1) as starting material. Sulfation was performed using trimethylamine-sulfur trioxide complex in dimethylformamide as the sulfating agent. The acetylcholinesterase inhibitory activity of compound 8 was evaluated and compared to that of disodium 2β,3α-dihydroxy-5α-cholestane disulfate (10) and diols 7 and 9. Compounds 8 and 10 were active with IC(50) values of 14.59 and 59.65 μM, respectively. Diols 7 and 9 showed no inhibitory activity (IC(50)>500 μM).  相似文献   

15.
Datura meteloides; plants were fed with tiglic acid-[-14C] via the roots and after 2 days the percentage incorporation into the alkaloids 3α-tigloyloxytropane, 3α,6β-ditigloyloxytropane, meteloidine and 3α,6β-ditigloyloxytropan-7β-ol were 15·2, 1·82, 2·2 and 1·8 respectively. 3α,6β-Ditigloyloxytropane was partially hydrolysed to 6β-hydroxy-3α-tigloyloxytropane which contained 58·1% of the radioactivity of the original base, whereas 3α,6β-ditigloyloxytropan-7β-ol gave meteloidine containing only 9·2% of the original activity. The results suggest that the di- and tri-hydroxytropanes may be formed by different routes.  相似文献   

16.
The synthesis of labeled and non-labeled 3β,15α-dihydroxy-5-pregnen-20-one (V) and 3β, 15α-dihydroxy-5-androsten-17-one (XI) is described. Treatment of 15α-hydroxy-4-pregnene-3,20-dione (I) with acetic anhydride and acetyl chloride gave 3,15α-diacetoxy-3,5-pregnadien-20-one (II). The enol acetate (II) was ketalized by a modification of the general procedure to yield 3,15α-diacetoxy-3,5-pregnadien-20-one cyclic ethylene ketal (III) which was then reduced with NaBH4 and LiAlH4 to give 3β, 15α-dihydroxy-5-pregnen-20-one cyclic ethylene ketal (IV). Cleavage of the ketal group of IV gave V. Similarly, XI was prepared by starting with 15α-hydroxy-4-androstene-3,17-dione (VII). The (4-14C)-3β,15α-dihydroxy-5-pregnen-20-one was prepared by a modification of the above procedure in that the enol acetate (II)was directly reduced with NaBH4 and LiAlH4 to yield 5-pregnene-3β,15α,20β-triol (XIII) which was then oxidized enzymatically with 20β-hydroxysteroid dehydrogenase to V.  相似文献   

17.
HE3286, 17α-ethynyl-5-androstene-3β, 7β, 17β-triol, is a novel synthetic compound related to the endogenous sterol 5-androstene-3β, 7β, 17β-triol (β-AET), a metabolite of the abundant adrenal steroid dehydroepiandrosterone (DHEA). HE3286 has shown efficacy in clinical studies in impaired glucose tolerance and type 2 diabetes, and in vivo models of types 1 and 2 diabetes, autoimmunity, and inflammation. Proteomic analysis of solid-phase HE3286-bound bead affinity experiments, using extracts from RAW 264.7 mouse macrophage cells, identified 26 binding partners. Network analysis revealed associations of these HE3286 target proteins with nodes in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways for type 2 diabetes, insulin, adipokine, and adipocyte signaling. Binding partners included low density lipoprotein receptor-related protein (Lrp1), an endocytic receptor; mitogen activated protein kinases 1 and 3 (Mapk1, Mapk3), protein kinases involved in inflammation signaling pathways; ribosomal protein S6 kinase alpha-3 (Rsp6ka3), an intracellular regulatory protein; sirtuin-2 (Sirt2); and 17β-hydroxysteroid dehydrogenase 1 (Hsd17β4), a sterol metabolizing enzyme.  相似文献   

18.
Oxysterols are cytotoxic agents. The gallbladder epithelium is exposed to high concentrations of oxysterols, and so elucidating the mechanisms of cytotoxicity in this organ may enhance our understanding of the pathogenesis of biliary tract disorders. We investigated the cytotoxic effects of the oxysterol cholestan-3β,5α,6β-triol (TriolC) on dog gallbladder epithelial cells. Apoptosis was the major form of cytotoxicity, as determined by analysis of nuclear morphologic changes and by multiparameter flow cytometry. Hydrophobic bile salts are known to have cytotoxic effects, whereas hydrophilic bile salts have cytoprotective effects. We therefore examined whether the hydrophobic bile acid taurodeoxycholic acid (TDC) and the hydrophilic bile acid tauroursodeoxycholic acid (TUDC) had modifying effects on oxysterol-induced cytotoxicity. TriolC caused an increase in the number of apoptotic cells from 14±11% (control) to 48±12% of total cells (P<0.01). After combining TriolC with TDC, cell apoptosis increased to 63±16% (P<0.05), whereas after addition of TUDC, the number of apoptotic cells decreased to 31±12% (P<0.05) of total cells. In summary, oxysterols such as TriolC induce apoptosis. Hydrophobic bile salts enhance TriolC-induced apoptosis, whereas hydrophilic bile salts diminish TriolC-induced apoptosis. These results suggest that interactions between oxysterols and bile salts play a role in the pathophysiology of biliary tract disorders.  相似文献   

19.
To determine if the conversion of the intermediate, 3α, 7α, 12α-trihydroxy-5β-cholestan-26-oic acid (THCA), into cholic acid is influenced by taurocholate, two rats were infused intravenously with [3H] THCA until they reached a steady state. Taurocholate was then added and infused at a rate of 1 μmole/min/rat for 48 hours. The percentage of [3H] THCA recovered in the bile did not increase indicating that taurocholate does not suppress the conversion of THCA into cholic acid.  相似文献   

20.
《Phytochemistry》1987,26(3):755-759
From Schkuhria schkuhrioides, two new sesquiterpene lactones, schkuhridin A and schkuhridin B, were isolated. Their structures and relative stereochemistry were assigned by chemical and spectral evidence. A separate proof for the structures of the novel compounds was provided by the transformation of budlein B to schkuhridin B via basic hydrolysis. Cope rearrangement and relactonization.  相似文献   

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