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1.
The total sterols have been isolated fromHalocynthia aurantium by column chromatography on silica gel. The following steroid alcohols have been identified in it with the aid of GLC, GLC-MS, and1H NMR: 5α-cholestan-3β-ol, 24ξ-methylcholestan-3β-ol, 24ξ-ethylcholestan-3β-ol, 4ξ-methyl-24ξ-ethyl-5α-cholestan-3β-ol, cholest-5-en-3β-ol, 24ξ-methylcholest-5-en-3β-ol, 24ξ-ethylcholes-5-en-3β-ol, 5α-cholest-22-en-3β-ol, 24-nor-5α-cholest-22-en-3β-ol, cholesta-5,22-dien-3β-ol, 24ξ-methylcholesta-5,22-dien-3β-ol, 24-norcholesta-5,22-dien-3β-ol, 24-ethylcholesta-5,24(28)-dien-3β-ol, and 24-methylcholesta-5,24(28)-dien-3β-ol.  相似文献   

2.
The starfish Asterias amurensis overy contains a saponin, 20ε-hydroxyl-6α-0-{-β-D-quinovopyranosyl (1→2)-β-D-galactopyranosyl (1→4)-[β-D-quinovopyranosyl (1→2)]-β-D-xylopyranosyl-(1→3)-β-D-quinovopyranosyl}-3β-sulfo-oxy-5α-cholest-9 (11)-en-23-one.  相似文献   

3.
Reduction of 6/7-carboethoxy-3-phenyltrop-3-en-2-ones with H2/Pd/C and NaBH4 was studied in order to find a stereoselective route to the corresponding 3-phenyltropan-2-ones and 2α/2β-hydroxy-3-phenyltropanes. The 6/7-exo-carboethoxy-3-phenyltrop-3-en-2-ones were selectively reduced by Pd/C to 3β-phenyltropan-2-ones and 2α-hydroxy-3β-phenyltropanes. The corresponding 2β-hydroxy-3β-phenyl analogues were synthesized using NaBH4, with a yield of 40%. Reduction of 6-endo-carboethoxy-3-phenyltrop-3-en-2-one yielded several products. The corresponding 7-endo-substituted analogue was selectively reduced with both Pd/C and NaBH4 to 7-endo-carboethoxy-3β-phenyltropin-2-one. Analysis of stereochemically important 1H NMR spectroscopy parameters was performed for all the products and used for conformational analysis in solution. X-ray analysis was performed for selected compounds.  相似文献   

4.
Experiments towards a synthesis of ecdysone ( 1 ) ([22R]-2β, 3β, 14, 22, 25-pentahydroxy-5β, 14α-cholest-7-en-6-one) have led to 2β, 3β-dihydroxy-6-keto-5α-steroids. These could be epimerized to the corresponding 5β-series. The proposed configurational assignments are supported by physical data and chemical correlation.  相似文献   

5.
The BF3-catalysed rearrangement of 6β-acetoxy-3α,5-epoxy-5α-cholestane gave the 3α,5β-diol, the 3α,10α-epoxide, and the 2α,5α-epoxide, and the product of solvolysis of 3β-tosyloxy-5β-cholestan-5-ol-6-one was identified as 3α,5-epoxy-A-homo-B-nor-5α-cholestan-4a-one.  相似文献   

6.
A new ketosteroid, 6β,16β-dihydroxycholest-4-en-3-one (1), in addition to the known 6β-hydroxycholest-4-en-3-one (2), 6β-hydroxycholest-4,22-dien-3-one (3) and 16β-hydroxy-5α-cholestan-3,6-dione (4), was isolated from the red alga Jania adhaerens. The structures were assigned on the basis of (1)H- and (13)C-NMR experiments. The new compound (1) was evaluated for its genotoxic and cytotoxic activities and found to possess protective antigenotoxicity in human peripheral blood cells.  相似文献   

7.
- 14α-Methyl-5α-cholest-9(11)-en-3β-ol (2) and 4α,14α-dimethyl-5α-cholest-9(11)-en-3β-ol (3) have been isolated from the sea cucumber Psolusfabricii and characterised by 1H NMR, 13C NMR and mass spectrometry. Lanost-9(11)-en-3β-ol (4) has also been tentatively identified. The relevance of this series of Δ9(11)-sterols to holothurin biosynthesis is briefly discussed.  相似文献   

8.
H. Hugl  E. Zbiral 《Tetrahedron》1973,29(5):753-757
The reaction of 7-dehydrocholesterylbenzoate with the title reagent at a temperature of ?20° yields 50% 1, 3β-benzoyloxy-5α,14α-diazidocholest-7-en-6-one, and 25% 2, 3β-benzoyloxy-5α- azido-cholest-7-en-6-one. Under the same conditions 3,5-cholestadiene yields 3α,6β-diazidocholest-4- ene (40%; 3) and 6β-azido-cholest-4-en-3-one (6%; 4). The structure elucidation of the compounds 1–4 is supported by spectroscopy.  相似文献   

9.
J.Bryan Jones  P. Price 《Tetrahedron》1973,29(14):1941-1947
Quantitative comparisons of the product ratios of the mechanistically similar diazomethane and Tiffeneau-Demjanov homologations of 17β-hydroxy-5α-androstan-3-one and 5α-cholestan-3-one have shown that equatorial approach of diazomethane to the C-3 CO group predominates to the extent of 70–79%. The data for both the C-17β-OH and -C8H17 substituted steroids are in close agreement thereby confirming that the C-17 substituents do not exert any significant long range effect on the reactions studied.  相似文献   

10.
A new ecdysteroid — nusilsterone — has been insolated from the whole plantSilene nutans L. It has been shown that it is 1β,2β,3β,14α,20R,22R,24ζ,25-octahydroxy-5-β-cholest-7-en-6-one.  相似文献   

11.
A chloroform-methanol extract of the musculocutaneous sac of the Far-Eastern holothurianC. japonica has yielded a fraction of sterol sulfates (13% of the weight of the extract, 0.8% of the weight of the dry biomass), the main components of which were derivatives of cholest-5-en-3β-ol, 24-methylene-, 24-ethyl-, and 24-ethylidenecholest-5-en-3β-ols, 5α-cholestan-3β-ol, and 24-methyl- and 24-methylene-5α-cholesten-3β-ol; among the minor components were found the sulfates of 24-ethyl-5α-cholestan-3β-ol of cholesta-5,22-dien-3β-ol, of a Δ5-C30 sterol, and also of dienic and trienic C26 sterols.  相似文献   

12.
I. Victor Ekhato 《合成通讯》2013,43(16):2341-2349
(4′R)- and (4′S)-Spiro(oxirane-2,4′-5α-cholestan-3′β-ol) (1) and (2) were made from (4′R)- and (4′S)-spiro(oxirane-2,4′-5α-cholestan-3-one) (8) and (9). Alkaline hydrogen peroxide oxidation of 4-methylene-5α-cholestan-3-one (7) gave compounds (8) and (9) as a readily separable (1:1) mixture. Reduction of (9) to (2) provided access to a compound which could not be made by other methods.  相似文献   

13.
The synthesis of the C2-symmetric bis-(20S)-5α-23,24-bisnorchol-16-en-3β,6α,7β-triol-22-terephthaloate (1), active as Na+-transporting transmembrane channel, has been achieved in 16 steps (10% overall yield) starting from the commercially available androst-5-en-3β-ol-17-one (3). The straightforward stereospecific functionalization of the side-chain, via the ‘ene’ reaction, and the successful regioselective terephthaloylation of the C-22 hydroxy group, illustrate the efficiency of the synthetic strategy.  相似文献   

14.
20, 21-Aziridine Steroids: Reaction of Derivatives of the Oximes of 5-Pregnen-20-one, 9β, 10α-5-Pregnen-20-one and 9β, 10α-5,7-Pregnadiene-20-one with Lithium Aluminium Hydride, and of 3β-Hydroxy-5-pregnen-20-one Oxime with Grignard Reagents. Reduction of 3β-hydroxy-5-pregnen-20-one oxime ( 2 ) with LiAlH4 in tetrahydrofuran yielded 20α-amino-5-pregnen-3β-ol ( 1 ), 20β-amino-5-pregnen-3β-ol ( 3 ), 20β, 21-imino-5-pregnen-3β-ol ( 6 ) and 20β, 21-imino-5-pregnen-3β-ol ( 9 ). The aziridines 6 and 9 were separated via the acetyl derivatives 7 and 10 . The reaction of 6 and 9 with CS2 gave 5-(3β-hydroxy-5-androsten-17β-yl)-thiazolidine-2-thione ( 8 ). Treatment of the 20-oximes 12 and 15 of the corresponding 9β,10α(retro)-pregnane derivatives with LiAlH4 gave the aziridines 13 and 16 , respectively. Their deamination led to the diene 14 and triene 17 , respectively. Reduction of isobutyl methyl ketone-oxime with LiAlH4 in tetrahydrofuran yielded 2-amino-4-methyl-pentane ( 19 ) as main product, 1, 2-imino-4-methyl-pentane ( 22 ) as second product and the epimeric 2,3-imino-4-methyl-pentanes 20 and 21 as minor products. – 3β-Hydroxy-5-pregnen-20-one oxime ( 2 ) was transformed by methylmagnesium iodide in toluene to 20α, 21-imino-20-methyl-5-pregnen-3β-ol ( 23 ) and 20β, 21-imino-20-methyl-5-pregnen-3β-ol ( 26 ). Acetylation of these aziridines was accompanied by elimination reactions leading to 3β-acetoxy-20-methylidene-21-N-acetylamino-5-pregnene ( 30 ) and 3β-acetoxy-20-methyl-21-N-acetylamino-5,17-pregnadiene ( 32 ). The reaction of oxime 2 with ethylmagnesium bromide in toluene gave 20α, 21-imino-20-ethyl-5-pregnen-3β-ol ( 24 ) and 20α,21-imino-20-ethyl-5-pregnen-3β-ol ( 27 ). Acetylation of 24 and 27 led to 3β-acetoxy-20-ethylidene-21-N-acetylamino-5-pregnene ( 31 ), 3β-acetoxy-20-ethyl-21-N-acetylamino-5,17-pregnadiene 33 and 3β, 20-diacetoxy-20-ethyl-21-N-acetylamino-5-pregnene ( 37 ). With phenylmagnesium bromide in toluene the oxime 2 was transformed to 20β, 21-imino-20-phenyl-5-pregnen-3β-ol ( 25 ) and 20β,21-imino-20-phenyl-5-pregnen-3β-ol ( 28 ). Acetylation of 25 and 28 yielded 3β-acetoxy-20-phenyl-21-N-acetylamino-5, 17-pregnadiene ( 34 ) and 3β,20-diacetoxy-20-phenyl-21-N-acetylamino-5-pregnene ( 39 ). LiAlH4-reduction of 39 gave 3β, 20-dihydroxy-20-phenyl-21-N-ethylamino-5-pregnene ( 41 ). – The 20, 21-aziridines are stable to LiAlH4. Consequently they are no intermediates in the formation of the 20-amino derivatives obtained from the oxime 2 .  相似文献   

15.
2-Deoxyecdyzone (3β,14α,22R,25-tetraoxy-5β-cholest-7-en-6-one) has been isolated from Silene cretaceae Fisch. Caryophyllaceae. The compound structure has been elucidated by X-ray diffraction studies.  相似文献   

16.
Carbon isotope ratio (CIR) analysis has been routinely and successfully applied to doping control analysis for many years to uncover the misuse of endogenous steroids such as testosterone. Over the years, several challenges and limitations of this approach became apparent, e.g., the influence of inadequate chromatographic separation on CIR values or the emergence of steroid preparations comprising identical CIRs as endogenous steroids. While the latter has been addressed recently by the implementation of hydrogen isotope ratios (HIR), an improved sample preparation for CIR avoiding co-eluting compounds is presented herein together with newly established reference values of those endogenous steroids being relevant for doping controls. From the fraction of glucuronidated steroids 5β-pregnane-3α,20α-diol, 5α-androst-16-en-3α-ol, 3α-Hydroxy-5β-androstane-11,17-dione, 3α-hydroxy-5α-androstan-17-one (ANDRO), 3α-hydroxy-5β-androstan-17-one (ETIO), 3β-hydroxy-androst-5-en-17-one (DHEA), 5α- and 5β-androstane-3α,17β-diol (5aDIOL and 5bDIOL), 17β-hydroxy-androst-4-en-3-one and 17α-hydroxy-androst-4-en-3-one were included. In addition, sulfate conjugates of ANDRO, ETIO, DHEA, 3β-hydroxy-5α-androstan-17-one plus 17α- and androst-5-ene-3β,17β-diol were considered and analyzed after acidic solvolysis. The results obtained for the reference population encompassing n?=?67 males and females confirmed earlier findings regarding factors influencing endogenous CIR. Variations in sample preparation influenced CIR measurements especially for 5aDIOL and 5bDIOL, the most valuable steroidal analytes for the detection of testosterone misuse. Earlier investigations on the HIR of the same reference population enabled the evaluation of combined measurements of CIR and HIR and its usefulness regarding both steroid metabolism studies and doping control analysis. The combination of both stable isotopes would allow for lower reference limits providing the same statistical power and certainty to distinguish between the endo- or exogenous origin of a urinary steroid.  相似文献   

17.
J.R. Bull  A. Tuinman 《Tetrahedron》1973,29(8):1101-1107
Conjugate methylation of 17β-hydroxy-des-a-oestr-9-en-5-one (1) and the derived 4,5-seco-steroid (6b) afforded the respective 9β-methyl compounds. Base-catalysed alkylation of 17β-hydroxy-9-methyl-des-a-9/gb-oestran-5-one (3a) resulted in attack at C(6); this result was used to prepare the anthrasteroid (5). Ring closure of the 9β-methyl-4,5-seco-steroid (8) derived from 6b afforded 17β-hydroxy-9-methyl-9β,10α-oestr-4-en-3-one (9a). Conjugate methylation of 17β-hydroxyoestra-4,9-dien-3-one (11) resulted in 1,4-addition to the dienone system.  相似文献   

18.
(Z)-3β-Acetoxy- and (Z)-3 α-acetoxy-5, 10-seco-1 (10)-cholesten-5-one ( 6a ) and ( 7a ) were synthesized by fragmentation of 3β-acetoxy-5α-cholestan-5-ol ( 1 ) and 3α-acetoxy-5β-cholestan-5-ol ( 2 ), respectively, using in both cases the hypoiodite reaction (the lead tetraacetate/iodine version). The 3β-acetate 6a was further transformed, via the 3β-alcohol 6d to the corresponding (Z)-3β-p-bromobenzoate ester 6b and to (Z)-5, 10-seco-1 (10)-cholestene-3, 5-dione ( 8 ) (also obtainable from the 3α-acetate 7a ). The 1H-and 13C-NMR. spectra showed that the (Z)-unsaturated 10-membered ring in all three compounds ( 6a , 7a and 8 ) exists in toluene, in only one conformation of type C 1, the same as that of the (Z)-3β-p-bromobenzoate 6b in the solid state found by X-ray analysis. The unfavourable relative spatial factors (interdistance and mutual orientation) of the active centres in conformations of type C 1 are responsible for the absence of intramolecular cyclizations in the (Z)-ketoesters 6 and 7 ( a and c ).  相似文献   

19.
The energy barrier to inorganic ion conduction through bilayer lipid membranes (BLM) is investigated as a function of molecular packing and dipolar potential characteristics. Arrhenius energy barrier information is derived from temperature-dependent electrochemical experiments with phosphatidyl choline/steroid BLM. The steroids studied at 0.65 mole fraction in phospholipid were 5-cholesten-3β-ol, 5,7-cholestadien-3β-ol, 5-cholesten-3β,7α-diol, 5α-cholestan-3β,5α,6β-triol, 5α-cholestan-5α,6α-epoxy-3β-ol, 5-cholesten-3β-ol-7-one and 5α-cholestan-3-one. Correlation of the barrier magnitude with molecular packing characteristics, obtained by collecting monolayer data from a Langmuir-Blodgett trough, indicates that the BLM ion current is almost completely controlled by molecular density. The sensitivity of the energy barrier as a function of molecular packing is as great as 0.1 eV for a 0.01-nm2 adjustment.  相似文献   

20.
Tordanone, a Twice Bent Steroid Structure with Ring A/B β-cis(5β)- and Ring B/C α-cis(8α)-Fused The 3β, 14α, 25-trihydroxy-5β, 8α-cholestan-6-one ( = tordanone; 4 ) has been prepared by stereospecific hydrogenation of 3β, 14α, 25-trihydroxy-5β-cholesta-7,22ξ-dien-6-one ( 5 ). This is the first stereospecific synthesis of a B/C cis-fused steroid belonging to the 5β, 8α -cholestane group with a H-atom at positions 5β (A/B cis-fused) and 8α. The resulting twice bent structure shows a particularly strong steric hindrance of the β-face where CH3(18) at the C/D ring junction and Hβ? C(7) of the B ring are very close to each other. Structural features and mechanistic aspects of the hydrogenation are discussed.  相似文献   

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