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1.
Microbial hydroxylation of pregnenolone derivatives   总被引:1,自引:0,他引:1  
Pregnenolone and pregnenolone acetate were incubated with the fungi Cunninghamella elegans, Rhizopus stolonifer and Gibberella fujikuroi. Incubation of with C. elegans yielded metabolites, 3beta,7beta,11alpha-trihydroxypreg-5-en-20-one, 3beta,6alpha,11alpha,12beta,15beta-pentahydroxypreg-4-en-20-one and 3beta,6beta,11alpha-trihydroxypreg-4-en-20-one, while incubation with G. fujikuroi yielded two known metabolites, 3beta,7beta-dihydroxypregn-5-en-20-one and 6beta,15beta-dihydroxypreg-4-ene-3,20-dione. Metabolites and were found to be new. Fermentation of by C. elegans yielded four known oxidative metabolites, androsta-1,4-diene-3,17-dione, 6beta,15beta-dihydroxyandrost-4-ene-3,17-dione and 11alpha,15beta-dihydroxypreg-4-ene-3,20-dione. Fermentation of with R. stolonifer yielded two known metabolites, 11alpha-hydroxypreg-4-ene-3,20-dione and. Compounds were screened for their cholinesterase inhibitory activity in a mechanism-based assay.  相似文献   

2.
Two new ent-kaurane-type diterpenoids,6β,7β,13α-trihydroxy-1α-acetoxy-7α,20-epoxy-ent-kaur-16-en-15-one(1)and 15β- hydroxy-6,7-seco-6,11β:6,20-diepoxy-1α,7-olide-ent-kaur-16-ene(2)were isolated from the Isodon nervosus,and the structures were elucidated by spectroscopic analysis.  相似文献   

3.
Six new ent-kaurane-type diterpenoids were isolated from the leaves of the endemic Vietnamese medicinal plant Croton tonkinensis GAGNEP. (Euphorbiaceae) together with three known ent-11alpha-acetoxy-7beta,14alpha-dihydroxykaur-16-en-15-one (1), ent-kaur-16-en-15-one 18-oic acid (5) and ent-18-hydroxykaur-16-ene (7). Their structures were determined by spectroscopic analyses to be ent-7beta-acetoxy-11alpha-hydroxykaur-16-en-15-one (2), ent-18-acetoxy-11alpha-hydroxykaur-16-en-15-one (3), ent-11alpha-acetoxykaur-16-en-18-oic acid (4), ent-15alpha,18-dihydroxykaur-16-ene (6), ent-11alpha,18-diacetoxy-7beta-hydroxykaur-16-en-15-one (8), and ent-(16S)-1alpha,14alpha-diacetoxy-7beta-hydroxy-17-methoxykauran-15-one (14). ent-Kaurane-type diterpenoids from Croton tonkinensis 2-4, 6, and 9-13, were tested for toxicity in the brine shrimp lethality assay. Compounds 9, 10, and 12 demonstrated significant activity, compounds 2, 3, 6, and 11 showed weak activity, and compounds 4 and 13 were inactive.  相似文献   

4.
New Ambra Odorants by Photoreactions of 15, 16-Dinorlabd-8(20)-en-13-one . UV.-irradiation of 15,16-dinorlabd-8(20)-en-13-one ( 1 ) led to the fragmentation product 4 and its photo-cyclisation product 5 . Ethers 6 and 7 and the βγ-unsaturated alcohols 8 and 10 were formed via ketone 9 , a double bond isomer of 1 . The olfactory properties of the photo-products are described.  相似文献   

5.
The aerial parts of Erigeron annuus (L.) PERS., E. philadelphicus L. and E. sumatrensis RETZ. (Compositae) have been investigated chemically. A new sesquiterpenoid, 6beta,14-epoxyeudesm-4(15)-en-1beta-ol (1), and a new diterpenoid, philadelphinone (6), have been isolated from E. philadelphicus. Four new sesquiterpenoids, (7R*)-opposit-4(15)-ene-1beta,7-diol (2), 11-methoxyopposit-4(15)-en-1beta-ol (3), 15-methoxyisodauc-3-ene-1beta,5alpha-diol (4) and 10alpha-hydroxycadin-4-en-15-al (5), have been isolated from E. annuus. Compounds 2 and 4 were also isolated from E. sumatrensis. The structures of the new compounds were elucidated on the basis of their spectral data.  相似文献   

6.
Four ent-kaurane-type diterpenoids from Croton tonkinensis Gagnep   总被引:3,自引:0,他引:3  
From the leaves of the endemic Vietnamese medicinal plant Croton tonkinensis GAGNEP. (Euphorbiaceae) the four new ent-kaurane-type diterpenoids ent-1alpha,14alpha-diacetoxy-7beta-hydroxykaur-16-en-15-one (1), ent-1alpha,7beta-diacetoxy-14alpha-hydroxykaur-16-en-15-one (2), ent-18-acetoxy-14alpha-hydroxykaur-16-en-15-one (3), and ent-(16S)-18-acetoxy-7beta-hydroxykauran-15-one (4) were isolated. Their structures were elucidated by spectroscopic analyses.  相似文献   

7.
Biotransformation of oleanolic acid (OA) by Circinella muscae AS 3.2695 was investigated. Nine hydroxylated and glycosylated metabolites (1–9) were obtained. Their structures were elucidated as 3β,7β-dihydroxyolean-12-en-28-oic acid (1), 3β,7β,21β-trihydroxyolean-12-en-28-oic acid (2), 3β,7α,21β-trihydroxyolean-12-en- 28-oic acid (3), 3β,7β,15α-trihydroxyolean-12-en-28-oic acid (4), 7β,15α-dihydroxy- 3-oxo-olean-12-en-28-oic acid (5), 7β-hydroxy-3-oxo-olean-12-en-28-oic acid (6), oleanolic acid-28-O-β-D-glucopyranosyl ester (7), 3β,21β-dihydroxyolean-12-en-28- oic acid-28-O-β-D-glucopyranosyl ester (8), and 3β,7β,15α-trihydroxyolean-12-en- 28-oic acid-28-O-β-D-glucopyranosyl ester (9) by spectroscopic analysis. Among them, compounds 4 and 9 were new compounds. In addition, anti-inflammatory activities were assayed and evaluated for the isolated metabolites. Most of the metabolites exhibited significant inhibitory activities on lipopolysaccharides-induced NO production in RAW 264.7 cells.  相似文献   

8.
Phytochemical investigation of the medicinal plant Isodon phyllostachys led to the isolation of four new ent‐kaurane diterpenoids, phyllostacins F–I ( 1 – 4 , resp.), together with 11 known compounds, rosthorin A ( 5 ), rabdoternin C ( 6 ), enmenol ( 7 ), oridonin ( 8 ), lasiocarpanin ( 9 ), xerophilusin B ( 10 ), ponicidin ( 11 ), macrocalin B ( 12 ), phyllostachysin A ( 13 ), sculponeatin C ( 14 ), and macrocalyxoformin E ( 15 ). The structures of the new compounds were established by spectroscopic methods, including extensive 1D‐ and 2D‐NMR analyses. Compounds 1, 2, 7, 10 , and 13 were evaluated for their inhibitory activity against K562 and HepG2 cell lines.  相似文献   

9.
The microbial transformation of levonorgestrel (1) by Cunningham elegans resulted in the formation of five hydroxylated metabolites, 13-ethyl-10beta, 17beta-dihydroxy-18,19-dinor-17alpha-pregn-4-en-20-yn-3-one(2), 13-ethyl-6beta,17beta-dihydroxy-18,19-dinor-17alpha-pregn-4-en-20-yn-3-one (3) 13-ethyl 6beta, 10beta, 17beta-trihydroxy-18,19-dinor-17alpha-pregn-4-en-20-yn-3-one (4) 13-ethyl-15alpha-17beta-dihydroxy-18,19-dinor-17alpha-pregn-4-en-20-yn-3-one (5) and 13-ethyl-11alpha, 17beta-dihydroxy-18,19-dinor-17alpha-pregn-4en-20-yn-3-one. The fermentation of one with Rhizopus stolonifer, Fusarium lini and Curvularia lunata afforded compound 2 as a major metabolise. These metabolites were structurally characterized on the basis of spectroScopic techniques. Metabolite 6 was identified as a new compound. Compounds 2 2 ad 5 displayed inhibitory activity against the acetylcholinesterase ( AChE, EC. 3.1.1.7) with IC50 values of 79.2 and 24.5 microM, respectively. The metabolites 2 and 5 also showed inhibitory activity against the butyryLcholinesterase ( BChE, E.C 3.1.1.8) with IC50 values ranging between 9.4 and 309.8 microM.  相似文献   

10.
Four new sesquiterpenoids, 1,4-trans-6-hydroxyisocalamenene; 1,4-trans-6-methoxyisocalamenene; (+)-aristol-9-en- 12β-ol, and eudesm-4(15)-en-6β-acetoxy-7β-ol, were isolated from Bazzania tridens, a liverwort species. Their structures were identified by means of spectroscopic methods. The two isocalamenenes are derived from a methyl rearrangement of the calamenene skeleton.  相似文献   

11.
Three new diterpenoids, excoecarins V1-V3 (1-3) and a new flavanone glycoside (7) were isolated from the fresh stem of Excoecaria agallocha L. Their structures were elucidated as: 2alpha,3alpha,18-trihydroxy-3beta,20-epoxybeyer-15-ene (1), ent-2,3-secokaur-16-en-2,3-dioic acid (2), ent-3,4-seco-16alpha-hydroxyatis-4(19)-en-3-oic acid (3), and 3,5,7,3',5'-pentahydroxy-2R,3R-flavanonol 3-O-alpha-L-rhamnopyranoside (7) on the basis of spectroscopic data, chemical evidence, and/or X-ray analysis.  相似文献   

12.
In the course of searching for marker components, two new polyporusterones were isolated from the sclerotia of Polyporus umbellatus, together with another three known analogs. The structures of the new ones were elucidated as (20S,22R,24R)-16,22-epoxy-3beta,14alpha,23beta,25-tetrahydroxyergost-7-en-6-one (1) and (23R,24R,25R)-23,26-epoxy-3beta,14alpha,21alpha,22alpha-tetrahydroxyergost-7-en-6-one (2) by chemical and spectroscopic means, including HR-FAB-MS, 1D- and 2D-NMR.  相似文献   

13.
The syntheses of 24-methylidene[24-14C]cholesterol ( 7a ) and of 24-methylidene[7-3H]cholesterol ( 7b ) from commercially available (20S)-3-oxopregn-4-ene-20-carbaldehyde ( 1 ) are described. The method also provides simple preparations of 3β-acetoxy[24-14C]chol-5-en-24-oic acid ( 4 ) and 24-oxocholest-5-en-3β-yl acetate ( 6b ).  相似文献   

14.
A new sulfated lupane triterpene, Gypsophilin (1), and its glucosyl ester, Gypsophilinoside (2) were isolated from the roots of Gypsophila repens whereas a new flavone C-glycoside (3) was obtained from the aerial parts. Their structures were established as (3beta)-3-O-(sulfo)lup-20(29)-en-23,28-dioic acid (1), (3beta)-3-O-(sulfo)lup-20(29)-en-23,28-dioic acid -28-O-beta-D-glucopyranosyl ester (2) and luteolin-7-O-alpha-L-arabinopyranosyl-6-C-beta-glucopyranoside (3) by spectroscopic methods such as 1D and 2D NMR, HR-ESI-MS and FAB-MS.  相似文献   

15.
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   

16.
Fourteen chemical constituents were isolated from the CHCl3 soluble portion of the heartwood of Melaleuca leucadendron L. These compounds include β-sitosterol (1) , β-sitostenone (2) , 6-hydroxy-4,6-dimethyl-3-hepten-2-one (3) , naphthalene (4) , squalene (5) , 2α3β-dihydroxyurs-12-en-28-oic acid (6) , 3β-hydroxylup-20(29)-en-27,28-dioic acid (7) , 2α,3β-dihydroxyolean-12-en-28-oic acid (8) , 3β,23-dihydroxyolean-12-en-28-oic acid (9) , 2α,3β,23-trihydroxyolean-12-en-28-oic acid (10) , 3β-trans-p-coumaroyloxy-2α,23-dihydroxyolean-12-en-28-oic acid (11) , and three novel oleanane derivatives 23-trans-p-coumaroyloxy-2α,3β-dihydroxyotean-12-en-28-oic acid (12), 3β-trans-caffeoyloxy-2α,23-dihydroxyolean-12-en-28-oic acid (13) , and its isomer 3β-cis-caffeoyloxy-2α,23-dihydroxyolean-12-en-28-oic acid (14) , The three novel compounds were characterized as the two and three O-methylated derivatives, respectively.  相似文献   

17.
藤黄化学成分的研究   总被引:5,自引:0,他引:5  
贾明美  寿清耀  谭青  沈征武 《化学学报》2008,66(22):2513-2517
传统中药藤黄通过各种色谱方法分离纯化, 得到15个化合物, 根据其理化性质和光谱方法鉴定其结构分别为: 2α-羟基-3β-乙酰氧基白桦酯酸(1), 10α-羟基表藤黄酸(2), 藤黄酸(3), 异藤黄酸(4), gambogin (5), gambogoic acid B (6), desoxymorellin (7), isomorellin (8), gambogenic acid (9), isogambogenin (10), gambogellic acid (11), desoxygambogenin (12), morellic acid (13), isomorellic acid (14), 30-hydroxygambogic acid (15). 其中化合物1和2为新化合物.  相似文献   

18.
(3E)-胆甾-4-烯-3,6-二酮-3-肟及其类似物的合成   总被引:4,自引:0,他引:4  
崔建国  范磊  黄立梁  肖蓉  黄燕敏 《合成化学》2007,15(6):689-692,743
以胆甾醇为原料,经氯铬酸吡啶氧化生成胆甾-4-烯-3,6-二酮(2),2与盐酸羟胺反应合成了(3E)-胆甾-4-烯-3,6-二酮-3-肟(3),总收率66%。利用合成3的反应条件合成了两个3的类似物——(3E)豆甾-4-烯-3,6-二酮-3-肟(6)和(3E)-谷甾-4-烯-3,6-二酮-3-肟(7)。2,3,6和7的结构经NMR和IR表征。  相似文献   

19.
<正>Microbial transformation of diosgenin(1) by Syncephalastrum racemosum yielded five new polar metabolites,which wereidentified as(25R)-spirost-5-en-3β,7α,9α-triol-12-one(2),(25R)-spirost-5-en-3β,9α,12α-triol-7-one(3),(25R)-spirost-5-en-3β,9α-diol-7,12-dione(4),(25R)-spirost-4-en-9α,12β,14α-triol-3-one(5),and(25S)-spirost-4-en-9α,14α,25β-triol-3-one(6).Compounds 1-6 exhibited moderate cytotoxicity against K562 cells and among them compounds 2,3,and 6 were more potentthan the parent compound 1.  相似文献   

20.
The polarographic behaviour of representative trichothecenes is described. Compounds characterized by an α,β-unsaturated carbonyl group or by a macrocyclic lactonic ring were found to be electroactive in a methanolic Britton—Robinson buffer. Differential pulse polarography provides detection limits of the order of 40 nmol l?1 with linear ranges extending up to 9 μmol l?1. The application of differential pulse polarography is described for the determination of nivalenol (3α, 4β, 7α, 15-tetrahydroxy-12,13-epoxytrichotec-9-en-8-one), deoxynivalenol (3α, 7α, 15-trihydroxy-12,13-epoxytrichothec-9-en-8-one) and fusarenone-X (3α, 7α, 15-trihydroxy-4 β-acetoxy-12,13-epoxytrichothec-9-en-8-one) in infected maize. A suitable liquid/liquid extraction and chromatographic cleanup procedure is reported. Detection limits for the overall procedure and for a sample size of 50 g are of the order of 50 ng g?1 while average recoveries range from 20 to 70% at the 1 μg g?1 level. Polarographic results are compared with those obtained by a gas-chromatographic method.  相似文献   

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