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1.
Sabudak T Tareq Hassan Khan M Iqbal Choudhary M Oksuz S 《Natural product research》2006,20(7):665-670
Trifolium balansae (Leguminosae) yielded a phytylester, phytyl-1-hexanoate, three steroids, stigmast-5-ene-3 beta,26-diol, stigmast-5-ene-3-ol and campesterol, and an alcohol, pentacosanol which were reported for the first time from T.balansae. The structures of the isolates were determined by 1D and 2D NMR techniques and MS spectroscopy. Compounds 1-5 were tested for their enzyme tyrosinase activity. While compounds 1 and 5 did not show any inhibition against the enzyme tyrosinase, compounds 2, 3, and 4 exhibited potent inhibition against tyrosinase. Highly potent (IC50 = 2.39 microM) inhibition was found by compound 2, when compared with the standard tyrosinase inhibitors Kojic acid and L-mimosine. 相似文献
2.
Md. Sohail Akhtar Raad A. Kaskoos Showkat Rasool Mir Mohammed Ali 《Journal of Saudi Chemical Society》2009,13(2):191-194
Phytochemical investigation of the aerial parts of Evolvulus alsinoides Linn. (Convolvulacae) resulted in the isolation of a new chromone characterized as 6-hydroxy-5-nonadecanoxychroman-2-one (alsinoideschromone) along with hexatriacontane, octyl octadec-9-enoate, nonyl octadec-9-enoate, dodecanyl-octadec-9,12-dienoate, tetracosanyl hexadec-9-enoate, heptacosan-14-β-ol, stigmast-5, 22-dien-3β-ol and stigmata-5-en-3β-ol. The structure of all these phytoconstituents have been established on the basis of spectral data analysis and chemical reactions. 相似文献
3.
Double bond isomerization of stigmasterol ((24S)-24-ethylcholesta-5,22-dien-3β-ol) with N-lithioethy-lenediamine produced stigmasta-5,17(20)-dien-3β-ol, stigmasta-5,20(22)-dien-3β-ol, stigmasta-5,23-dien-3β-ol and stigmasta-5,24-dien-3β-ol. Some starting material was also present in the isomerization mixture along with a small amount of stigmast-5-en-3β-ol. Similar treatment of 3α,5-cyclo-6β-methoxystigmast-22-en (stigmasterol i-methyl ether) followed by ozonization and removal of the ring A-protecting group yielded predominantly 3β-hydroxy-androst-5-en-17-one and 3β-hydroxypregn-5-en-20-one. The isomerization products of fucosterol (24-ethylcholesta- 5, 24(28)E-dien-3β-ol) and 23,24-bisnorchola-5,20-dien-3β-ol are also reported. 相似文献
4.
首次报道从中国南海海绵Polymas tia sobustia中分离得到5个纯化合物,经过MS,IR,1H NMR,13C NMR (DEPT),HMQC和HMBC等波谱技术鉴定为:豆甾-5-烯-7-羰基-3β-甾醇(1 ),N-(1-羟甲基-2,6-二羟基)十七烷基-5-羟基二十四脂肪酰胺([ ST5”HZ 2),胸腺嘧啶(3),尿嘧啶(4[ ST5”BZ ),对羟基苯甲酸(5);其中化合物1和化合 物2为新化合物。 相似文献
5.
Conforti F Marrelli M Statti G Menichini F Uzunov D Solimene U Menichini F 《Natural product research》2012,26(1):91-97
The two studied Calamintha species showed different polyphenolic content and sterol composition. Calamintha grandiflora possessed twice the polyphenolic content of Calamintha nepeta subsp. glandulosa, while the latter contained a higher number of sterols. Among them, stigmast-5-en-3β-ol was found to be the major constituent. The methanolic extract of C. grandiflora was more potent than the C. nepeta subsp. glandulosa methanolic extract in a DPPH assay, while the activity of the C. grandiflora EtOAc fraction was weaker than its C. nepeta subsp. glandulosa counterpart. Fractions of C. nepeta subsp. glandulosa showed higher activity using a β-carotene bleaching test. The petrol ether fraction of C. grandiflora showed significant inhibition of NO production. 相似文献
6.
The isolation and identification of fifteen compounds from the heartwood of Diospyros eriantha are described. Their structures were determined on the basis of spectral evidence and/or comparison with authentic samples. These compounds include three steroids (stigmast-4-en-3-one, stigmast-4-ene-3,6-dione, and 3β-hydroxystigmast-5-en-7-one), seven triterpenoids (friedelin, lupeol, betulinaldehyde, 3β-acetoxyurs-11-en-13,28-olide, 3β-acetoxyoleanolic acid, betulin, and betulinic acid), three quinones (2-ethoxy-7-methyljuglone, 3-ethoxy-7-methyljuglone, and 2,6-dimethoxy-1,4-benzoquinone), and two phenols (3,4,5-trimethoxyphenol, and syringic acid). 相似文献
7.
Pseudostellaria heterophylla (Miq.) Pax or Taizishen (TZS) is one of the most popular Traditional Chinese Medicines in China, and is commonly used to treat various lung and spleen diseases. In this work focused microwave-assisted solvent extraction (MAE) coupled with gas chromatography–mass spectrometry has been used for analyzing volatile components of TZS. The main compound in the extract were palmitic acid (21.37%), 9,12-octadecadienoic acid ethylester (16.98%), trans-oleic acid (5.94%), chondrillasterol (3.99%), stigmast-7-en-3-ol (3.92%), 5,6-dihydroergosterol(2.48%), 1-monolinolein (2.35%). Compared with Soxhlet extraction, the much shorter extraction time and the similar components in the extract make MAE an excellent alternative for extraction of the components of TZS. 相似文献
8.
Xanthium sibiricum patrin ex Widder (Compositae) is an annual herb which grows all around China. Chemical investigations of its roots resulted in the identification of 15 compounds: stigmast-4-en-6β-ol-3-one (1), β-sitostenone (2), β-sitosterol (3), nonadecanoic acid (4), 5α,8α-epidioxy-22E-ergosta-6,22-dien-3β-ol (5), scopoletin (6), Jatrocin B (7), (±)syringaresinol (8), 9,9'-O-di-(E)-feruloyl-(-)-secoisolariciresinol (9), cleomiscosin A (10), cleomiscosin C (11), N-trans-feruloyl tyramine (12), daucosterol (13), 5-methyluracil (14) and uracil (15). Structures were elucidated by spectroscopic (NMR and MS) methods and confirmed by comparing with reference samples and literature data. Compounds 1-2, 4-12, 14, and 15 were isolated from this genus for the first time, while this is the first report of coumarinolignoids in the Compositae family, and coumarinoligoids could be considered as valuable chemotaxonomic markers for the plant. 相似文献
9.
A new antimicrobial sesquiterpene isolated from endophytic fungus Cytospora sp. from the Chinese mangrove plant Ceriops tagal 总被引:1,自引:0,他引:1
AbstractChemical examination of Chinese mangrove Ceriops tagal endophytic Cytospora sp., yielded a new biscyclic sesquiterpene seiricardine D (1), and eight known metabolites, xylariterpenoid A (2a), xylariterpenoid B (2b) and regiolone (3) 4-hydroxyphenethyl alcohol (4), (22E, 24R)5, 8-epidioxy-5α, 8α-ergosta-6,22E-dien-3ß-ol (5), (22E, 24R)5, 8-epidioxy-5α, 8α-ergosta-6,9(11), 22-trien-3 ß-ol (6), ß-sitosterol (7) and stigmast-4-en-3-one (8). These structures were unambiguously elucidated on the basis of extensive NMR spectroscopic and mass spectrometric analyses. The antimicrobial activities of compounds 1–8 and their effects on a panel of plant and human pathogens were evaluated. 相似文献
10.
Nyunt KS Elkhateeb A Tosa Y Nabata K Katakura K Matsuura H 《Natural product communications》2012,7(5):609-610
Bioactivity-guided fractionation of an ethanolic extract of Vitis repens led to the isolation of resveratrol (1), 11-O-acetyl bergenin (2), and stigmast-4-en-3-one (3). The compounds were examined for their in vitro antitrypanosomal activities against trypomastigotes of Trypanosoma evansi. Resveratrol showed antitrypanosomal activity with an IC50 value of 0.13 microM, whereas 11-O-acetyl bergenin and stigmast-4-en-3-one exhibited IC50 values of 0.17 and 0.15 microM, respectively. 相似文献
11.
Juliawaty LD Kitajima M Takayama H Achmad SA Aimi N 《Chemical & pharmaceutical bulletin》2000,48(11):1726-1728
A new type of natural product, idenburgene (1), was isolated from Crytocarya idenburgensis, and its unique structure was elucidated. Four known compounds, 3-hydroxy-5-methoxystilbene (2), 2',6'-dihydroxy-4'-methoxydihydrochalcone (3), stigmast-4-ene-3-one, and beta-sitosterol were also isolated and identified. 相似文献
12.
《Arabian Journal of Chemistry》2020,13(7):6191-6200
An approach to metabolomics profiling of non-infected and Ganoderma boninense (G. boninsense) infected oil palm roots crude extracts that utilize gas chromatography-mass spectrometry (GC–MS) and multivariate statistics of principal component analysis (PCA) have been tested. This combination has provided a rapid approach in investigating the changes in the metabolite variations of non-infected and infected oil palm roots at 14 and 30 days post-infection. The extracts were prepared by using 80% (v/v) of methanol. In identifying the metabolites responsible for each differentiation, PCA model was generated in loading bi-plot. Dimethyl benzene-1,4-dicarboxylate, methyl 3-(3,5-ditert-butyl-4-hydroxyphenyl)propanoate, ergost-5-en-3-ol, (3β), stigmast-5-en-3-ol, (3β), stigmasterol, methyl hexadecanoate, methyl (9Z,12Z)-octadeca-9,12-dienoate, methyl octadecanoate, 2-(hydroxymethyl)-2-nitropropane-1,3-diol, methyl (Z)-octadec-6-enoate and (E)-icos-5-ene were found more abundant in G. boninense infected roots than in non-infected roots. Steroidal compounds and fatty acid derivatives which has been determined in the non-infected and G. boninense infected roots regulate a variety of responses to the G. boninense. The abundant of these metabolites in G. boninense infected roots are due to the crucial roles in pathogen defence. 相似文献
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14.
G. von Bünau G. Schade und K. Gollnick 《Fresenius' Journal of Analytical Chemistry》1967,227(4):270-278
Zusammenfassung Die Massenspektren von acht Caranolen (trans-Caran-trans-2-ol, cis-Caran-trans-2-ol, trans-Caran-trans-3-ol, cis-Caran-trans-3-ol, trans-Caran-cis-3-ol, cis-Caran-cis-3-ol, Caran-trans-4-ol und Caran-cis-4-ol) wurden untersucht. Aus der Zuordnung der metastabilen Ionen ergaben sich Hinweise auf den Mechanismus der Fragmentierung von Caranol-Ionen. Ein Vergleich der Massenspektren zeigte, da\ die quantitativen Unterschiede in den relativen IntensitÄten sowohl eine qualitative Identifizierung als auch eine quantitative Analyse von Caranolgemischen erlauben.
Summary The mass spectra of eight caranols (trans-carane-trans-2-ol, cis-carane-trans-2-ol, trans-carane-trans-3-ol, cis-carane-trans-3-ol, trans-carane-cis-3-ol, cis-carane-cis-3-ol, carane-trans-4-ol, and carane-cis-4-ol) were investigated. Certain aspects of the caranol ion fragmentation mechanism could be derived from an analysis of metastable ions. It is concluded that identification of caranols as well as quantitative analysis of caranol mixtures can be based solely on quantitative evaluation of abundance ratios.相似文献
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16.
Pharmacologically active stigmast-4-en-3-one, the maximum formation of which (93.4 %) was achieved in the presence of n-hexadecane and palmitic acid, was produced by biotransformation of β-sitosterol (6 g/L) using rhodococcus cells. β-Sitosterol was added to the incubation medium as a mixture with β-cyclodextrin and Tween-80. The biotransformation processing conditions were optimized for β-sitosterol at high concentrations (10 g/L) using R. erythropolis IEGM 90 cells to catalyze formation of stigmast-4-en-3-one (75 %). 相似文献
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18.
A new natural terpenoid, ixoroid (1), was isolated from the flower of Ixora coccinea, along with the known constituents stigmast-5-en-3-O-beta-D-glucoside (2), 5-O-caffeoylquinic acid (3) and D-mannitol (4). The structure of ixoroid was elucidated on the basis of extensive 1D- and 2D-NMR studies and mass spectrometry as 21,23-epoxy-tirucall-7-en-3beta-ol (1). 相似文献
19.
CUI Jian-guo ZENG Long-mei ** SU Jing-yu LIN Cui-wu . School of Chemistry Chemical Engineering Zhongshan University Guangzhou P. R. China . Department of Chemistry Guangxi Teachers College Nanning P. R. China . Department of Chemistry Guangxi University Nanning P. R. China 《高等学校化学研究》2002,18(4):400-404
IntroductionThe reduction of carbonyl groups is one of themostfundamental operations in organic chemistry.Catalytic hydrogenation,metal- amine solutions,and complex metal hydrides often allow a veryclean and selective reduction of one carbonyl groupin the presence of another or other functionalgroup[1— 3] .New methods and new reagents whichoffer even a greater selectivity are constantly beingsought.In the study of selective reduction tosteroidal diketone,we discovered that reducingagents cons… 相似文献
20.
The Identification of Two New Sterols from Marine Organism 总被引:2,自引:0,他引:2
Marineorganismsproducedmanyinterestingphannacologicallyandbiologicallyactiviemetabolitessuchasantibacterium,anticancerandantimicrobialactivecompounds'-'.lnrecentyears,avarietyofsterolshavebeenreportedfrommarineinvertebratesandsponges'-'.Moreandmorechemistsandbiologistspayattentiontotheconstituentsofspongesandcorals.ThirteencompoundshavebeenisolatedfromthespongePolymastiasobustiaandeightycompoundshavebeenobtainedfromthesoftcoralSinulariainexPlicita.InthispaPerwewou1dliketoreportthestructurale… 相似文献