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1.
Furuta T  Namekawa T  Shibasaki H  Kasuya Y 《Steroids》1999,64(12):805-811
A method is described for the preparation of multi-labeled tetrahydrocortisol (3alpha,11beta,17alpha,21-tetrahydroxy-5beta-[1, 2,3,4,5-2H5]pregnan-20-one, THF-d5), allo-tetrahydrocortisol (3alpha,11beta,17alpha,21-tetrahydroxy-5alpha-[1 ,2,3,4,5-2H5]pregnan-20-one, allo-THF-d5), and tetrahydrocortisone (3alpha,17alpha,21-trihydroxy-5beta-[1,2,3,4,5-2H5]pre gnane-11,20-dione, THE-d5) containing five non-exchangeable deuterium atoms in the steroid ring A. Reductive deuteration at C-1, C-2, C-3, C-4, and C-5 of prednisolone or prednisone was performed in CH3COOD with rhodium (5%) on alumina under the deuterium atmosphere. The isotopic purities of the labeled compounds as [2H5]-form were estimated to be 86.17 atom%D for THF-d5, 74.46 atom%D for allo-THF-d5 and 81.90 atom%D for THE-d5, based on the ion intensities in the region of the molecular ion of methoxime-trimethylsilyl (MO-TMS) derivatives measured by GC-MS.  相似文献   

2.
Abbott GD  Bashir FZ  Sugden MA 《Chirality》2001,13(8):510-516
The distribution of the free and bound hopanoic acids in both unheated and heated (350 degrees C for 50 h) kerogens, isolated from the Messel oil shale, were analyzed by GC-MS. The bound acids were released by subjecting the kerogen to three different treatments, namely, thermochemolysis in the presence of tetramethylammonium hydroxide (TMAH), as well as basic and acidic hydrolyses. All of these methods gave a series of hopanoic acids ranging from C(30) to C(34), in which the biological 17beta, 21beta(H) configuration is prominent. Both 22R and 22S epimers are present for the C(30) acid, whereas the others are dominated by the sidechain 22R-configuration. Thermochemolysis in the presence of TMAH was the most efficient in releasing kerogen-bound hopanoids. Following pyrolysis, the acids are generated and released into the free fraction with apparent epimerization occurring at C-17, C-21, and C-22. The bound hopanoic acids may be both chemically bonded as well as possibly being physically encapsulated within the macromolecular fraction of sedimentary organic matter. They are therefore either generated by breaking the bonds which bind them to the kerogen or they are released as a result of the macromolecular cage being broken apart.  相似文献   

3.
Disodium 3beta,21-dihydroxypregn-5-en-20-one disulfate (2), sodium 3beta,21-dihydroxypregn-5-en-20-one 3-sulfate (3), sodium 3beta,21-dihydroxypregn-5-en-20-one 21-sulfate (4), and disodium 3beta,6alpha-dihydroxy-5alpha-pregnan-20-one disulfate (6) have been synthesized and completely characterized for the first time from readily available materials. Sulfation was performed using triethylamine-sulfur trioxide complex in dimethylformamide as the sulfating agent. Selective sulfation of 3beta,21-dihydroxypregn-5-en-20-one rendered sodium 3beta,21-dihydroxypregn-5-en-20-one 3-sulfate (3) as the major compound. The synthetic sulfated steroids as well as natural disulfated polyhydroxysteroids (7-9) isolated by us from the antarctic ophiuroid Astrotoma agassizii and the synthetic derivatives disodium 2beta,3alpha,21-trihydroxy-(20R)-cholesta-5,24-diene 3-acetate, 2,21-disulfate (7a) and 2beta,3alpha,21-trihydroxy-(20R)-cholesta-5,24-diene (7b) were comparatively evaluated for their inhibitory effect on the replication of one DNA (HSV-2) and two RNA (PV-3, JV) viruses. In general, steroids with sulfate groups at C-21 and C-2 or C-3 were the most effective in their inhibitory action against HSV-2 and also proved to be active against PV-3 and JV.  相似文献   

4.
Zhang Z  Li S 《Phytochemistry》2007,68(15):2075-2086
Continued chemical investigation on the fruits of North American Aesculus pavia L. resulted in the isolation and identification of 13 polyhydroxyoleanene pentacyclic triterpenoid saponins, named aesculiosides IIe-IIk (1-7), and IIIa-IIIf (8-13), together with 18 known compounds: aesculiosides Ia-Ie (14-18), IIa-IId (19-22), IVa-IVc (23-25), 3-O-[beta-D-galactopyranosyl(1-->2)]-alpha-L-arabinofuranosyl(1-->3)-beta-D-glucuronopyranosyl-21,22-O-diangeloyl-3beta,15 alpha,16 alpha,21 beta,22 alpha,28-hexahydroxyolean-12-ene (26), 3-O-[beta-D-glucopyranosyl(1-->2)]-alpha-L-arabinofuranosyl(1-->3)-beta-D-glucuronopyranosyl-21,22-O-diangeloyl-3beta,16 alpha,21 beta,22 alpha,24 beta,28-hexahydroxyolean-12-ene (27), 3-O-[beta-D-galactopyranosyl(1-->2)]-alpha-L-arabinofuranosyl(1-->3)-beta-D-glucuronopyranosyl-21,22-O-diangeloyl-3beta,16 alpha,21 beta,22 alpha,28-pentahydroxyolean-12-ene (28), R(1)-barrigenol (29), scopolin (30), and 5-methoxyscopolin (31). The structures of these compounds were elucidated by spectroscopic and chemical analyses. Compounds 14-22 and 26-28 were tested in vitro for their activity against 59 cell lines from nine different human cancers including leukemia, non-small cell lung, colon, CNS, melanoma, ovarian, renal, prostate, and breast. It was found that compounds with two-acyl groups at C-21 and C-22 had cytotoxic activity for all cell lines tested with GI(50) 0.175-8.71 microM, while compounds without acyl groups at C-21 and C-22 had weak or no cytotoxic activity. These results suggest that the acyl groups at C-21 and C-22 are essential for their activity.  相似文献   

5.
Two proteins in the rat, androgen binding protein (ABP) and the cytoplasmic receptor (CR), have high affinity and limited capacity for binding androgens. To determine the structural requirements for binding with high affinity, each protein was partially purified and the ability of over 100 steroids to compete with [3H]dihydrotestosterone (17 beta-hydroxy-5 alpha-androstan-3-one) for binding sites was assessed. The results indicate marked differences in the steroid specificities of the two proteins. Some alterations of dihydrotestosterone at C-2 or C-2 and C-3 increase binding to ABP two to four-fold. Similarly, the affinity of 17 beta-hydroxy-7 alpha-methyl-4-estren-3-one for ABP increases two-fold when a double bond is created at C-14. Addition of a methyl group in the alpha position at C-7 or C-17, or an ethinyl group at C-17 cause little change in affinity; however, modifications at C-11 and C-17 beta, and deletion of the methyl group at C-10 significantly impair binding to ABP. Binding to the CR is maintained or increased by deletion of the methyl group at C-10. Binding is lessened by modifications at C-3 and C-17 beta. Most alterations at C-2, C-7, C-11, and C-17 alpha have only minor effects on binding to the CR. These studies should provide a molecular basis for predicting the effects of specific structural modifications. When some modifications at C-2 or C-2 and C-3 are combined with changes at C-17 beta, the resulting steroids retain very high affinity for ABP and very limited binding to the CR. Such steroids may provide a means for assessing the function of ABP.  相似文献   

6.
Lamm AS  Chen AR  Reynolds WF  Reese PB 《Steroids》2007,72(9-10):713-722
The fungi Whetzelinia sclerotiorum ATCC 18687, Phanerochaete chrysosporium ATCC 24725 and Mucor plumbeus ATCC 4740 were examined for their ability to perform steroid biotransformations under single phase, pulse feed conditions. The steroids 3beta-hydroxyandrost-5-en-17-one (dehydroepiandrosterone) (1), 17beta-hydroxyandrost-4-en-3-one (testosterone) (5), 3beta-hydroxypregn-5-en-20-one (pregnenolone) (3), pregn-4-ene-3,20-dione (progesterone) (9), 17alpha,21-dihydroxypregn-4-ene-3,11,20-trione (cortisone) (11), 17alpha,21-dihydroxypregna-1,4-diene-3,11,20-trione (prednisone) (14), and 3-hydroxyestra-1,3,5(10)-trien-17-one (estrone) (15) were fed to each fungus. The production of a number of novel metabolites is reported. Of the fungi investigated W. sclerotiorum performed the most interesting biotransformations and had a clear propensity for 2beta, 6beta/7beta and 15beta/16beta hydroxylations. P. chrysosporium was more prone functionalize steroids in the allylic position. Oxygen insertion at C-14 by M. plumbeus is reported for the first time. All three micro-organisms exhibited redox activity.  相似文献   

7.
Park KK  Ko DH  You Z  Khan MO  Lee HJ 《Steroids》2006,71(3):183-188
A series of new anti-inflammatory steroidal antedrugs with C-16,17-isoxazoline ring system were synthesized and their pharmacological activities were evaluated. We reported earlier that these compounds are promising antedrugs based on the results of 5-day rat croton oil ear edema assay. In the present study, most of these compounds showed high binding affinities to the glucocorticoid receptor of liver cytosol. 21-acetyloxy-9alpha-fluoro-11beta-hydroxy-3,20-dioxo-1,4-pregnadieno [16alpha,17alpha-d] isoxazoline (FP-ISO-21AC) and 11beta,21-dihydroxy-9alpha-fluoro-3,20-dioxo-1,4-pregnadieno [16alpha,17alpha-d] isoxazoline (FP-ISO-21OH) were found 5.0-, 5.3-fold more potent than prednisolone, respectively. Inhibitory effects of the antedrugs on the nitric oxide (NO) production were assessed using LPS-stimulated RAW 264.7 murine macrophage cells. All these steroidal antedrugs exhibited concentration-dependent inhibition of NO production, but their relative potencies were lower than prednisolone. In vitro metabolism study in rat plasma showed that FP-ISO-21AC and 21-acetyloxy-9alpha-fluoro-11beta-hydroxy-3,20-dioxo-1,4-pregnadieno [16alpha,17alpha-d]-3'-hydroxyiminoformyl isoxazoline (FP-OXIM-21AC) were hydrolyzed rapidly, with the half-lives of 2.1 and 4.2 min, respectively. The half-lives of FP-ISO-21OH and 11beta,21-dihydroxy-9alpha-fluoro-3,20-dioxo-1,4-pregnadieno [16alpha,17alpha-d]-3'-hydroxyiminoformyl isoxazoline (FP-OXIM-21OH) were 92.2 and 110.2 min, respectively.  相似文献   

8.
C Monder  H L Bradlow  C A Han  B Zumoff 《Steroids》1985,45(3-4):375-382
We have previously shown that human subjects metabolize the 20 beta-epimer of isocortisol (11 beta, 17,20 beta-trihydroxy-3-oxo-pregn-4-en-21-al) to both 20 alpha- and 20 beta-hydroxy steroid end products. In this paper we describe the synthesis of tritium labeled 20 alpha-epimers of isocortisol and isoTHF (3 alpha, 11 beta, 17,20 alpha-tetrahydroxy-5 beta-pregnan-21-al) and their metabolic fate in humans. Both steroids yielded 20 alpha-hydroxy urinary neutral end-products (cortols and cortolones) and no 20 beta-hydroxy epimers. Regeneration of 17-ketols from aldols occurred to a small extent with isoTHF, but not with isocortisol. Isocortisol and isoTHF yielded less cortoic acids than did the corresponding ketols. The results provide further evidence that in man the stereochemistry at C-20 of the end-products of corticosteroid metabolism is determined by the configuration of the aldol at C-20 prior to subsequent metabolic events.  相似文献   

9.
Microbial transformation was used to prepare novel cytotoxic bufadienolides. Twelve products (3-14) were obtained from bufalin (1) by the fungus Mucor spinosus. Their structures were elucidated by high-resolution mass spectroscopy (HR-MS) and extensive NMR techniques, including 1H NMR, 13C NMR, DEPT, 1H-1H correlation spectroscopy (COSY), two dimensional nuclear Overhauser effect correlation spectroscopy (NOESY), heteronuclear multiple quantum coherence (HMQC), and heteronuclear multiple bond coherence (HMBC). Compounds 3, 4, 9 and 11-14 are new mono- or dihydroxylated derivatives of bufalin with novel oxyfunctionalities at C-1beta, C-7beta, C-11beta, C-12beta and C-16alpha positions. The in vitro cytotoxic activities against human cancer cell lines of 3-14, together with 16 biotransformed products derived from cinobufagin (15-30) were determined by the MTT method, and their structure-activity relationships (SAR) were discussed.  相似文献   

10.
As enzymatic hydroxylation of 5 alpha-androstane-3 beta,17 beta-diol (3 beta-diol) may be a factor in controlling the 5 alpha-dihydrotestosterone (DHT) content in the prostate, we were interested in activity and distribution of these enzymes in epithelium and stroma of human benign prostatic hyperplasia (BPH). The enzyme activities were measured after mechanical separation of BPH tissue from 15 patients of various ages into stroma and epithelium, and optimization of the in vitro transformation of 3 beta-diol to hydroxylated products, which were analyzed by HPLC. The main results were: (1) 3 beta-diol was hydroxylated at C-7 alpha, C-7 beta, C-6 alpha, and C-6 beta. (2) The mean Michaelis constant Km (nM +/- SEM) for hydroxylation at C-7 alpha(beta) (168 +/- 21) was significantly lower than at C-6 alpha(beta) (601 +/- 43) without differences between stroma and epithelium. (3) Hydroxylation at alpha position dominated significantly over that at beta. (4) The mean maximal metabolic rate Vmax (pmol . mg protein-1 . h-1) of hydroxylation at C-6 alpha was about 7-fold lower in stroma (3.4 +/- 0.2) than in epithelium (23.8 +/- 4.1), concerning the other hydroxylations, Vmax was about 1.6-fold lower in stroma. (5) With increasing age of the patients there was a significant decrease of the 3 beta-diol hydroxylation in stroma and epithelium. It is discussed that the significantly lower activity of 3 beta-diol hydroxylation in stroma compared to epithelium and the decrease of activity with increasing age might potentiate the DHT accumulation in stroma of BPH.  相似文献   

11.
Steroidal epoxy and/or N-oxy 17-picolyl and 17-picolinylidene-androst-5-ene derivatives have been prepared using 3beta,17beta-dihydroxy-17alpha-picolyl-androst-5-ene (1), 3beta-acetoxy-17-picolinylidene-androst-5-ene (2), and 3beta-hydroxy-17-picolinylidene-androst-5-ene (3) as synthetic precursors. The compounds 2 and/or 3 were reacted with m-chloroperoxybenzoic acid (MCPBA). The compounds synthesized from 2 were 17-picolinylidene-N-oxide 4, 5alpha,6alpha-epoxy and 5beta,6beta-epoxy-17-picolinylidene-N-oxide 5 and 6, and 5alpha,6alpha:17alpha,20alpha- and 5beta,6beta:17alpha,20alpha-diepoxy-N-oxide 7 and 8. Starting from compound 3, a mixture of 5alpha,6alpha-epoxy and 5beta,6beta-epoxy-17-picolinylidene 9 and 10, 5alpha,6alpha-epoxy and 5beta,6beta-epoxy-17-picolinylidene-N-oxide 11 and 12, and 5alpha,6alpha:17alpha,20alpha- and 5beta,6beta:17alpha,20alpha-diepoxy-N-oxide 13 and 14 were obtained. From compounds 15 and 18, obtained from 1 and 3 by the Oppenauer oxidation, the 4alpha,5alpha-epoxy and 4beta,5beta-epoxy derivatives 16, 17 and 20, 21 were prepared by oxidation with 30% H(2)O(2). Oxidation of 18 with MCPBA yielded only the N-oxide 19. The structures of compounds 15 and 18 were proved by the X-ray analysis. Compounds 1-6, 9, 15, 17, 18, and 21 were tested on activity against the enzyme aromatase. Antitumor activity against three tumor cell lines (human breast adenocarcinoma ER+, MCF-7, human breast adenocarcinoma ER-, MDA-MB-231, and prostate cancer PC3) was evaluated. Three tested compounds (1, 4, and 19) showed strong activity against PC3, the IC(50) values being in the range 0.55-10microM, whereas compound 17 showed strong activity against MDA-MB-231 (IC(50) 10.4microM).  相似文献   

12.
Clostridium sp. strain S1, an unnamed bile acid-desulfating strain from rat intestinal microflora (S.M. Huijghebaert, J. A. Mertens, and H. J. Eyssen, Appl. Environ. Microbiol. 43:185-192, 1982), was examined for its ability to desulfate different bile acid sulfates and steroid sulfates in growing cultures. Clostridium sp. strain S1 desulfated the 3 alpha-monosulfates of chenodeoxycholic, deoxycholic, and cholic acid, but not their 7 alpha- or 12 alpha-monosulfates. Among the 3-sulfates of the 5 alpha- and 5 beta-bile acids, only bile acid-3-sulfates with an equatorial sulfate group were desulfated. Hence, Clostridium sp. strain S1 desulfated the 3-sulfates of bile acids with a 3 alpha, 5 beta-, a 3 beta, 5 alpha- or a 3 beta, delta 5-structure. In contrast, the bile acid-3-sulfates with a 3 beta, 5 beta- or a 3 alpha, 5 alpha-structure were not desulfated. In addition, Clostridium sp. strain S1 did not hydrolyze the equatorial 3-sulfate esters of C19 and C21 steroids and cholesterol or the phenolic 3-sulfate esters of estrone and estradiol. 23-Nordeoxycholic acid with a C-23 carboxyl group was also not desulfated, in contrast to the 5 beta-bile acid 3 alpha-sulfates with a C-24 or C-26 carboxyl group. Therefore, the specificity of the sulfatase of Clostridium sp. strain S1 is related to the location of the sulfate group on the bile acid molecule, the equatorial orientation of the sulfate group, and the structure of the C-17 side chain, its carboxyl group, and chain length.  相似文献   

13.
The 7 beta progesterone-hydroxylating microorganism Botryosphaerica obtusa was tested for its ability to hydroxylate at this site the C-19 androstene-based compounds, androstenedione (androst-4-ene-3,17-dione) and testosterone (17 beta-hydroxyandrost-4-en-3-one). Only very limited 7 beta hydroxylation of both substrates was observed. The products included traces of 7 beta-monohydroxytestosterone and 6 beta,7 beta-dihydroxyandrostenedione from testosterone, and of 6 beta,7 beta-dihydroxyandrostenedione from androstenedione. 6 beta,7 beta-Dihydroxyandrostenedione does not appear to have been reported previously as a microbial transformation product. Both substrates were monohydroxylated in significant amounts at the isomeric 7 alpha site and at the 6 beta site. Testosterone was also significantly monohydroxylated at the 15 alpha site and in minor amounts at the 11 alpha and 12 beta sites. Some monohydroxytestosterones had also been oxidised at their 17-OH group, converting them into the corresponding monohydroxy androstenediones. The 7 alpha-hydroxy metabolites and 15 alpha-hydroxytestosterone being chemically demanding to synthesis are valuable microbial transformation products.  相似文献   

14.
The synthesis and properties of a radiolabeled glycoside photoaffinity probe, [3H]-(3 beta,5 beta,14 beta, 20E)-24-azido-3-[(2,6-dideoxy-beta-D-ribo-hexopyranosyl) oxy]-14-hydroxy-21-norchol-20(22)-en-23-one, containing the photoactive group at the C-17 side chain of the steroid moiety are reported. The molecule binds to the sodium- and potassium-activated adenosinetriphosphatase from porcine kidney outer medulla under type II binding conditions [5 mM MgCl2, 3 mM phosphate, 2 mM ethylenediaminetetraacetic acid, 30 mM tris(hydroxymethyl)aminomethane, pH 7.2, 37 degrees C] in the dark with an equilibrium dissociation constant of (1.4 +/- 0.3) X 10(-7) M. Ultraviolet irradiation of a solution of enzyme plus 3H-labeled probe, followed by analysis of covalently incorporated radiolabel, shows ouabain-displaceable labeling exclusively of the alpha subunit of the sodium- and potassium-activated adenosinetriphosphatase. These data indicate that the binding site of the C-17 side group of cardiac glycosides is located on or near the alpha subunit of this enzyme.  相似文献   

15.
Preparative methods were developed for reduction with NaBH4 at 0 of 3 beta, 5 alpha- and 3 alpha, 5 beta-tetrahydroaldosterone (1) and (12) to their respective 20 alpha-ol derivatives 2a and 13a. Corroboration of structures was obtained by periodate oxidations to the lactols 3b and 14b and thence, by further oxidation, to the lactones 4 and 15 respectively; these lactones were also independently obtained from 1 and 12. Reduction with NaBH4 at 80 degrees C converted 1 and 12 into 18-hydroxy-3 beta, 5 alpha, 20- and 18-hydroxy-3 alpha, 5 beta, 20-hexahydrocorticosterone 6a and 17a respectively, which were mixtures of epimers at C-20. Compound 17a could also be prepared by reduction of the lactone 21 with sodium aluminum bis-(methoxyethoxy) hydride. Again, periodate oxidations of 6a and 17a gave the lactols 7b and 22b and thence, by Jones oxidation, the diketolactones 8 and 23, which were also prepared from 18-hydroxy-11-dehydrocorticosterone (10) and 18-hydroxycorticosterone (24) respectively. Improved conditions for reduction with Clostridium paraputrificum permitted convenient conversion of aldosterone (11), the corresponding 18 leads to 11 lactone 18a and 18-hydroxycorticosterone (24) into their 3 alpha, 5 beta-tetrahydro derivatives.  相似文献   

16.
Although 19-hydroxy-4beta,5-oxido-5beta-androstane-3,17 dione (2a) is converted to estradiol-17beta by human placental microsomes, the incubation of 17beta-hydroxy-4beta,5-oxido-5beta-androstan-3-one (2b) under the same conditions produces only metabolites which are more polar than 17beta-estradiol. The metabolites have been isolated and identified as 3alpha-hydroxy-4beta,5-oxido-5beta-androstan-17-one (4a), 4beta,5-oxido-5beta-androstane-3beta, 17beta-diol (5a) and 4beta,5-oxido-5beta-androstane-3alpha,17beta-diol (6a). These results indicate that functionalization at C-19 is a prerequisite for the biological aromatization of such androgen epoxides.  相似文献   

17.
Triterpenoids have been isolated from the lipids of the anaerobic, photosynthetic bacterium, Rhodomicrobium vannielii. These compounds constitute various hopanoids, including hydrocarbons, 22-, 29-and 3-hydroxy, 3-keto-, C-3 and C-21 methyl-triterpenoids, as well as fernenes.  相似文献   

18.
A series of derivatives of estrone with fluorescent dyes (dansyl or coumarin) coupled at different positions on the steroid molecule, have been synthesized. These derivatives were tested for their quantum yields and their binding properties were determined with respect to rat alpha 1 fetoprotein. Derivatives at C-3 (estrone-3-hemisuccinate-dansyl-cadaverine and estrone-3-dansyl) compete with estrone for binding to the fetal protein; however derivates of estrone at C-6 (estrone-6-carboxymethyloxime-dansyl-cadaverine) and at C-17 (estrone-17-carboxymethyloxime-coumarine, estrone-17-carboxymethyloxime-dansyl-cadaverine and estrone-17-dansyl-hydrazine) compete poorly or not at all. The association constant of the radioactive derivative estrone-3-dansyl [3H] with rat alpha 1 fetoprotein was measured directly: the same number of high affinity binding sites (0.6) as that for estrone was found with an apparent association constant of 3.7 X 10(6) M-1. In addition to the high affinity binding sites, a low affinity class of binding sites was found which corresponds to the binding of the dansyl fraction of the fluorescent steroid derivative.  相似文献   

19.
G Halperin  I Maschler 《Steroids》1979,33(1):33-44
The proportion of 20 alpha/20 beta-epimers of the urinary C21-steroid metabolites was estimated in normal volunteers and in patients with congenital adrenal hyperplasia (CAH), postpubertal virilizing syndrome (PVS) and polycystic ovary syndrome (POS). In the normal individuals 20 alpha- and 20 beta-epimers of 5 beta-pregnane-3 alpha, 17 alpha, 20-triol (pregnanetriol) and 5-pregnene-3 beta, 17 alpha, 20-triol (5-pregnenetriol) were measured. In the other case 20 alpha- and 20 beta-epimers of the characteristic, representative metabolites were also investigated. In 26 of 27 normal persons and in all the patients with normotensive CAH, PVS and POS the 20 beta-epimer comprised 0-10% of the total pregnanetriol. The 20 beta-epimer of 5-pregnenetriol was found in only one normal case (6% of the total). The percentage of 20 beta-epimers of 3 alpha, 17 alpha, 20-trihydroxy-5 beta-pregnan-11-one, 5 beta-pregnane-3 alpha, 11 beta, 17 alpha, 20-tetrol (in the normotensive CAH, PVS and POS) and 5 alpha- or 5 beta-pregnane-3 alpha, 17 alpha, 20, 21-tetrol (in the hypertensive CAH) varied from nil to 76%. The effect of functional groups and the stereochemistry of the molecule on the direction of C-20-keto group reduction is discussed; the existence of additional factors determining this reduction in certain pathological conditions is suggested.  相似文献   

20.
Triterpenoids belonging to the hopane family are widely distributed in prokaryotes. Three new hopanoids have now been isolated from the purple non-sulphur bacterium Rhodomicrobium vannielii and identified essentially by spectroscopic methods. The basic compound is the 35-aminobacteriohopane-32,33,34-triol, from which the other two hopanoids are derived by introduction of a tryptophanyl or an ornithinyl moiety linked to the amino group at C-35 via an amide linkage. This is the first report of hopanoids possessing an amino group in their side-chain and linked to aminoacyl residues.  相似文献   

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