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1.
Bramble suspension cultures normally contain Δ5-sterols (sitosterol, campesterol and isofucosterol). When the cells were grown in a medium supplemented with 15-aza-24-methylene-d-homocholesta-8,14-dien- 3β-ol, Δ5-sterols disappeared almost completely whereas Δ8,14-sterols accumulated strongly. Five Δ8,14-sterols, including two new compounds, (24R)-24-ethyl-5α-cholesta-8,14-dien-3β-ol and 4α-methyl-5α-stigmasta-8,14, Z-24(28)-trien-3β-ol, were identified. The 15-azasterol probably inhibited the reduction of the Δ14-bond. Cell lines growing permanently in an azasterol-supplemented medium were obtained.  相似文献   

2.
When Chlorella sorokiniana was grown in the presence of 4 ppm AY-9944 total sterol production was unaltered in comparison to control cultures. However, inhibition of sterol biosynthesis was shown by the accumulation of a number of sterols which were considered to be intermediates in sterol biosynthesis. The sterols which were found in treated cultures were identified as cyclolaudenol, 4α,14α-dimethyl-9β,19-cyclo-5α-ergost-25-en-3β-ol, 4α,14α-dimethyl -5α-ergosta-8,25-dien-3β-ol, 14α-methyl-9β,19-cyclo-5α-ergost-25-en-3β-ol, 24-methylpollinastanol, 14α-methyl-5α-ergost-8-en-3β-ol, 5α-ergost -8(14)-enol, 5α-ergost-8-enol, 5α-ergosta-8(14),22-dienol, 5α-ergosta-8,22-dienol, 5α-ergosta-8,14-dienol, and 5α-ergosta-7,22-dienol, in addition to the normally occurring sterols which are ergosterol, 5α-ergost-7-enol, and ergosta-5,7-dienol.The occurrence of these sterols in the treated culture indicates that AY-9944 is an effective inhibitor of the Δ8 → Δ7 isomerase and Δ14-reductase, and also inhibits introduction of the Δ22-double bond. The occurrence of 14α-dimethyl-5α-ergosta-8,25-dien-3β-ol and 14α-methyl-9β,19-cyclo-5α-ergost -25-en-3β-ol is reported for the first time in living organisms. The presence of 25-methylene sterols suggests that they, and not 24-methylene derivatives, are intermediates in the biosynthesis of sterols in C. sorokiniana.  相似文献   

3.
In addition to the previously found ergosta-5, E-23-dien-3β-ol and 5α-ergosta-7, E-23-dien-3β-ol, the following Δ23 sterols have been identified in etiolated maize coleoptiles: cyclosadol, 4α, 14α-dimethyl-5α-ergosta-8, E-23-dien-3β-ol, 4α, 14α-dimethyl-9β, 19-cyclo-5α-ergosta-8, E-23-dien-3β-ol and 4α-methyl-5α-ergosta-7, E-23-dien-3β-ol. The incubation of maize coleoptile microsomes in the presence of cycloartenol and of [14C-methyl]S-adenosyl methionine gave a mixture of labelled 24-methylene cycloartanol and cyclosadol. No trace of cyclolaudenol could be detected in these conditions. It is suggested that Δ23 sterols are products of the C-24 methyltransferase reaction and they probably do not arise from a Δ24 → Δ23 isomerization occurring at a later stage of the biosynthesis. The Δ13-sterols may play an intermediary role in the biosynthesis of 24-methyl sterols in this plant material.  相似文献   

4.
The sterol content of the marine sponge Crambe crambe has been determined. The major components of the mixture are cholest-7-en3β-ol, 24-methylcholesta-7,22-dien-3β-ol and cholesta-7,22-dien-3β-ol. Significative quantities of the rare 4α-methyl-5α-cholest-8-en3β-ol are also present.  相似文献   

5.
The biotransformation of dehydrochloromethyltestosterone (DHCMT, 4-chloro-17β-hydroxy,17α-methylandrosta-1,4-dien-3-one) in man was studied with the aim to discover long-term metabolites valuable for the antidoping analysis. Having applied a high performance liquid chromatography for the fractionation of urinary extract obtained from the pool of several DHCMT positive urines, about 50 metabolites were found. Most of these metabolites were included in the GC-MS/MS screening method, which was subsequently applied to analyze the post-administration and routine doping control samples. As a result of this study, 6 new long-term metabolites were identified tentatively characterized using GC-MS and GC-MS/MS as 4-chloro-17α-methyl-5β-androstan-3α,16,17β-triol (M1), 4-chloro-18-nor-17β-hydroxymethyl,17α-methyl-5β-androsta-1,13-dien-3α-ol (M2), 4-chloro-18-nor-17β-hydroxymethyl,17α-methyl-5β-androst-13-en-3α-ol (M3), its epimer 4-chloro-18-nor-17α-hydroxymethyl,17β-methyl-5β-androst-13-en-3α-ol, 4-chloro-18-nor-17β-hydroxymethyl,17α-methylandrosta-4,13-dien-3α-ol (M4) and its epimer 4-chloro-18-nor-17α-hydroxymethyl,17β-methylandrosta-4,13-dien-3α-ol. The most long-term metabolite M3 was shown to be superior in the majority of cases to the other known DHCMT metabolites, such as 4-chloro-18-nor-17β-hydroxymethyl,17α-methylandrosta-1,4,13-trien-3-one and 4-chloro-3α,6β,17β-trihydroxy-17α-methyl-5β-androst-1-en-16-one.  相似文献   

6.
Shin K  Chin J  Hahn D  Lee J  Hwang H  Won DH  Ham J  Choi H  Kang E  Kim H  Ju MK  Nam SJ  Kang H 《Steroids》2012,77(5):355-359
Three new steroids 3-oxocholest-1,22-dien-12β-ol (1), 3-oxocholest-1,4-dien-20β-ol (2), 3-oxocholest-1,4-dien-12β-ol (3), and three known steroids (20S)-20-Hydroxyergosta-1,4,24(28)-trien-3-one (4) [7a], 5α,8α-Epidioxycholesta-6,22-dien-3β-ol (5) [10] and 5-cholestene-3β,12β-diol (6) [11] were isolated from a soft coral Dendronephthya gigantea. Their chemical structures and relative stereochemistry were elucidated by the analysis of HRMS and 2-D NMR spectroscopic data. The steroids 1 and 2 showed notable inhibitory activity against farnesoid X-activated receptor (FXR) with IC(50)'s 14 and 15μM.  相似文献   

7.
Hydroboration of 5α-cholesta-8,14-dien-3β-ol (I) gave 5α-cholest-8-en-3β,15α-diol (IV) in 89% yield. 5α-Cholest-7-en-3β,15α-diol (V) was prepared in 91% yield by hydroboration of 5α-cholesta-7,14-dien-3β-ol (II). Hydroboration of 27:63 mixture of I and II gave IV and V in 18% and 70% yields, respectively. 5α-Cholest-8-en-15α-ol-3-one and 5α-cholest-7-en-15α-ol-3-one were prepared in high yields from IV and V, respectively, by either selective oxidation with silver carbonate-celite or by enzymatic oxidation using cholesterol oxidase. 7α,8α-Epoxy-5α-cholestan-3β,15α-diol (VIII) was prepared in 93% yield by treatment of V with m-chloroperbenzoic acid. 5α-Cholest-8(14)-en-7α-ol-3,15-dione (IX) was prepared in 56% yield by oxidation of VIII with pyridinium chlorochromate followed by treatment of the crude product with acid. Compound IX was also obtained in 72% yield by selective chemical oxidation of 5α-cholest-8(14)-en-3β,7α,15α-triol. 5α-Cholesta-6,8(14)-dien-3,15-dione (X) was prepared in 89% yield by treatment of IX with p-toluenesulfonic acid under controlled conditions. Reduction of X with lithium tri-tert-butoxyaluminum hydride under controlled conditions gave 5α-cholesta-6,8(14)-dien-3β-ol-15-one in 84% yield.  相似文献   

8.
盾叶薯蓣内生真菌Dzf13抗细菌活性成分   总被引:1,自引:0,他引:1  
采用活性追踪分离的方法,从盾叶薯蓣内生真菌菌株Dzf13中分离到两个具抗细菌活性的化合物1和2,经理化和波谱分析鉴定为麦角甾-5,7,22-三烯-3β-醇(1)和5α,8α-过氧麦角甾-6,22-二烯-3β-醇(2).结果表明,化合物1和2对根癌土壤杆菌、黄瓜角斑病菌和番茄疮痂病菌等三种植物病原细菌的生长均表现出一定的抑制活性,尤其对黄瓜角斑病菌的抑制活性较强.结果还表明5α,8α-过氧麦角甾-6,22-二烯-3β-醇(2)的抗细菌活性要比麦角甾-5,7,22-三烯-3β-醇(1)强.  相似文献   

9.
The 4-desmethylsterol fraction of the liverwort Palavicinnia lyellii is composed of 36% 24β-methylcholest-5-en-3β-ol (dihydrobrassicasterol), 16% 24α-methylcholest-5-en-3β-ol (campesterol), 33% 24α-ethylcholest-5-en-3β-ol (sitosterol) and 15% 24ξ-ethylcholesta-5,22-dien-3β-ol.  相似文献   

10.
蓝柄丽齿菌的化学成分   总被引:3,自引:0,他引:3  
从担子菌亚门蓝柄丽齿菌(Calodon suaveolens)中首次分离得到8个化合物,通过波谱学技术并借助必要的化学方法最终确定结构,它们是:(22E,24R)-麦角甾-7,22-二烯-3β-醇(1),(22E,24R)-5α,8α-过氧麦角甾-6,22-二烯.3β-醇(2),(22E,24R)-麦角甾.5,7,22-三烯-3β-醇(3),(22E,24R)-3β-羟基麦角甾-5,22-二烯-7-酮(4),对羟基苯甲酸(5),尿嘧啶(6),polyozellin(7),(4E,BE)-2-N-(2’-羟基棕榈酰)-1-O-β-D-吡喃葡萄糖基-9-甲基-4,8-sphingadienine(8)。  相似文献   

11.
Fourteen 4α-methyl sterols have been isolated from the gorgonians Briareum asbestinum, Gorgonia mariae, Muriceopsis flavida and Pseudoplexaura wagenaari, including the following five new sterols: 4α-methyl-24-methylene-5α-cholestan-3β-ol, (24R)-4α, 24-dimethyl-5α-cholesta-7,22-dien-3,β-ol, 4α,24S(or 23ξ)-dimethyl-5α-cholest-7-en-3β-ol, (22E, 24R)-4α,23,24-trimethyl-5α-cholesta-7,22-dien-3β-ol and (24R)-4α,24-dimethyl-5α-cholesta-8(14),22-dien-3β-ol. There is strong evidence that these 4α-methyl sterols are synthesized by the algal (dinoflagellate) symbionts (zooxanthellae) of the gorgonians. It is suggested that analysis of 4Δ-methyl sterol mixtures isolated from a zooxanthellae-bearing invertebrate, collected in several different geographic locations, might give information on the specificity of the symbiotic association between a given animal species and a particular strain of zooxanthellae.  相似文献   

12.
The free sterol mixture of the sponge Psammaplysilla purpurea was shown to contain aplysterol as the major constituent. In addition to other sterols such as 5,7-cholestadien-3β-ol, cholesterol, 5α-cholestan-3β-ol, 24ε-methylcholesta-5,22-dien-3β-ol, 24ε-methylcholesterol, 24ε-ethylcholesta-5,22-dien-3β-ol and 24,28-dehydroaplysterol, a new minor sterol was isolated and shown by spectral analysis as well as partial synthesis to be 3β-hydroxy-26,27-bisnorcholest-5-en-24-one. The sterol mixture contains no other short side chain or 24-keto sterols except for small amounts of 3β-hydroxypregn-5-en-20-one and 3β-hydroxy-5α-pregnan-20-one.  相似文献   

13.
The dinoflagellate Glenodiniumhallii was investigated for its sterol composition. Five of the six sterols were isolated and identified as cholest-5-en-3β-ol, (24ξ)-24-methylcholest-5-en-3β-ol, stigmasta-5,22-dien-3β-ol, (22E,24R)-4α,23,24-trimethyl-5α-cholest-22-en-3β-ol, and 4α,23ξ,24ξ-trimethyl-5α-cholestan-3β-ol.  相似文献   

14.
本文对三种毒菌的化学成分进行了研究。从光盖伞(Psilocybe spp)分离鉴定了4个化合物,经波谱分析鉴定为:(22E,24R)-麦角甾-7,22-二烯-3β-十八烷酸酯(1)、β-胡萝卜苷(2)、(22E,24R)-5α,6α-环氧麦角甾-8,22-二烯-3β,7α-二醇(3)、色氨酸(4);从假褐云斑鹅膏(Amanita pseudoporphyria)分离鉴定了4个化合物:(22E,24R)-3β-羟基-5α,8α-过氧化麦角甾-6,22-二烯(5)、(22E,24R)-麦角甾-7,22-二烯-3β,5α,6β-三醇(6)、1-O-β-D-吡喃葡萄糖基-(2S,3R,4E,8E,2′R)-2-N-(2′-羟基棕榈酰)-9-甲基-4,8-脱氢鞘氨醇(7)、1-O-β-D-吡喃葡萄糖基-(2S,3R,4E,8E,2′R)-2-N-(2′-羟基十八烷酰)-9-甲基-4,8-脱氢鞘氨醇(8);大青褶伞(Chlorophyllum molybdites)发酵菌丝体分离鉴定了4个化合物:5、6、(22E,24R)-5α,6α-环氧麦角甾-8(14),22-二烯-3β,7α-二醇(9)、(22E,24R)-麦角甾-7,22-二烯-3β-醇(10)。除化合物9外其它化合物均为首次从以上相应毒菌中分离得到。  相似文献   

15.
The heterotrophic dinoflagellate Crypthecodinium cohnii contained the 4α-methyl sterols, dinosterol, dehydrodinosterol (4α,23,24-trimethylcholesta-5,22-dien-3β-ol) and the tentatively identified 4α,24-dimethyl-cholestan-3β-ol and 4α,24-dimethylcholest-5-en-3β-ol. The major 4-demethyl sterol was cholesta-5,7-dien-3β-ol which was accompanied by a smaller amount of cholesterol and traces of several other C27,C28 and C29 sterols. In addition, a 3-oxo-steroid fraction was isolated and the major component identified as dinosterone (4α,23,24-trimethylcholest-22-en-3-one). The possible biosynthetic relationships of these compounds are discussed.  相似文献   

16.
The sterol fraction of Argan seed oil (Argania spinosa) contains two main compounds, 5α-stigmast-7-en-3β-ol (schottenol) and 5α-stigmast-7,22(E)-dien-3β-ol (spinasterol).  相似文献   

17.
非洲隔囊蚁巢伞的化学成分研究(英文)   总被引:2,自引:0,他引:2  
从肯尼亚安波塞利产的隔囊蚁巢伞(Termitomyces schimperi)子实体中分离得到8个已知化合物,通过波谱方法鉴定它们的结构为(22E,24R)-麦角甾-5,7,22-三烯-3β-醇(1),(3β,5α,9α-三羟基麦角甾-7,22-二烯-6-酮(2),5α,8α-过氧-(22E,24R)-麦角甾-6,22-二烯-3β-醇(3),麦角甾-4,6,8(14),22-四烯-3-酮(4),D-阿拉伯糖醇(5),D-半乳糖醇(6),脑苷脂B(7)和脑苷脂D(8)。所有化合物均首次从该真菌中分离得到。  相似文献   

18.
为研究来源于哀牢山国家级自然保护区河谷的土壤真菌Aspergillus fumigatus固体发酵产物的化学成分及抗氧化活性研究,采用正相硅胶柱层析、反相硅胶柱层析和Sephadex LH-20分离纯化,借助核磁共振波谱等方法鉴定化合物结构,从中共得到13个化合物,分别鉴定为rubrofusarin B(1)、rubrofusarin A(2)、carbonarone A(3)、aspernigrin A(4)、flavasperone(5)、(22 E,24 R)-5α,8α-过氧麦角甾-6,22-二烯-3β-醇(6)、(22 E,24 R)-5α,8α-过氧麦角甾-6,9(11),22-三烯-3β-醇(7)、ourosperone A(8)、(22 E,24 R)-麦角甾-5,7,22-三烯-3β-醇(9)、stigmast-1,5-dien-3β-ol(10)、fonsecinones A(11)、asperpyrone C(12)、asperpyrones B(13)。其中,化合物1~5和7~13为从该菌种中首次分离。抗氧化活性结果显示,化合物8对DPPH(IC50=3.453 mg/mL)、ABTS+(IC50=0.155 mg/mL)、OH(IC50=0.019 mg/mL)自由基都有一定的清除效果。  相似文献   

19.
从角果胡椒的乙醇提取物中分离得到6个甾醇,通过波谱方法鉴定它们的结构为5α,8α-过氧-(22E,24R)-麦角甾-6,22-二烯-3β-醇(1),(22E,24R)-麦角甾-5,7,22-三烯-3β-醇(2),(22E,24R)-麦角甾-7,22-二烯-3β,5α,6β-三醇(3),豆甾醇-5,11-二烯-3β-醇(4),豆甾醇-3,6-二酮(5),sitoindosideΙ(6)。  相似文献   

20.
Brain sterols from chick embryos (11 and 18 days of incubation) and mature rats, previously injected with [2-14C]mevalonate, were analysed. Acetate derivatives of the sterols were chromatographed on Silica Gel:Celite:AgNO3 columns. Sterol fractions were assayed for radioactivity and the amounts determined by gas chromatography. Sterol structures were elucidated by gas chromatography-mass spectrometry. The method used allowed the identification of some sterols representing no more than 0-01 per cent of the total mixture. The following brain sterols were identified: cholesterol, cholestanol, cholest-5,24-dien-3β-ol (desmosterol); 4,4′-dimethyl-cholest-8-en-3β-ol, 4α-methyl-cholest-8-en-3β-ol, cholest-8-en-3β-ol, 4,4′-dimethyl-choIest-8,24-dien-3β-ol, 4α-methyl-cholest-8,24-dien-3β-ol, cholest-8,24-dien-3β-ol and cholest-7,24-dien-3β-ol. Small amounts of other sterols including polyhydroxy sterols, were also detected. There were no qualitative differences in the sterols detected in developing and mature brain. In the developing chick brain, cholesterol represented approximately 90 per cent of the total sterols. In the mature rat brain, cholesterol accounted for 98 per cent of the sterols. The adult rat brain, as well as the embryonic chick brain, demonstrated the capacity to incorporate mevalonate into cholesterol precursors and cholestanol. The sterols retaining the double bond in the lateral chain, that is, those of the Δ8,24 series with 29, 28 and 27 carbon atoms and desmosterol, were highly labelled compared with the other identified intermediates. The possibility, supported by our data, that a preferential biosynthetic route for cholesterol exists in brain, is discussed.  相似文献   

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