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21.
Samples of maize, rapeseed, soyabean, sunflower, and palm oils, collected at different stages in their respective refining processes, have been analyzed for the presence of dehydrated sterols (sterenes). A total of fifteen compounds were detected. Four have been characterized using model systems designed to investigate their formation. Their elemental composition, and that of the other eleven sterenes, was determined by high resolution mass spectrometry and structures assigned to a further six compounds. These included the -3,5-, -2,5-, -4,6-,-3,5,22-, and -4,6,22- sterenes. Sterenes were not present in crude or alkali neutralized oils. Bleaching introduced a maximum concentration of 5 μg g?1 of total sterenes into the edible oils. Deodorization is the dominant stage in sterene production resulting in a maximum total concentration of 163 μg g?1. This increased concentration arises due to dehydration of the sterols and considerable isomerism of the sterenes. 相似文献
22.
E. A. Khamidullina A. L. Vereshchagin S. A. Medvedeva 《Chemistry of Natural Compounds》2005,41(4):426-428
The newditerpene alcohol (1) in addition to the known metabolitesisoagatholal (2) and β-sitosterol glucoside (as the tetraacetate) (3) were isolated from buds of Siberian pine. The structure of the new compound was established as abieto-8(14)-en-18-ol 9α,13α-endoperoxide.
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Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 343–344, July–August, 2005. 相似文献
23.
多羟基甾醇的合成及其结构与抗肿瘤细胞活性关系研究 总被引:3,自引:0,他引:3
报道了6个具有类似结构的多羟基甾醇的合成和它们的抗肿瘤细胞活性.发现此类化合物的细胞毒性与其分子中双键存在与否有着密切关系.当甾核或支链中双键被饱和时,其细胞毒性均明显降低.甾醇(5)和(8)对胃癌(MGC)、宫颈癌(HELA)细胞的生长具有一定的抑制作用. 相似文献
24.
多羟基甾醇的合成及其结构与抗扣瘤细胞活性关系研究 总被引:11,自引:1,他引:10
报道了6个具有类似结构的多羟基甾醇的合成和它们的抗肿瘤细胞活性。发现此类化合物的细胞毒性与其分子中双键存在与否有着密切关系。当甾核或支链中双键被饱和时,其细胞毒性均明显降低。甾醇(5)和(8)对胃癌(MGC)、宫颈癌(HELA)细胞的生长具有一定的抑制作用。 相似文献
25.
Hao Gao Kui Hong Guo‐Dong Chen Chuan‐Xi Wang Jin‐Shan Tang Yang Yu Miao‐Miao Jiang Man‐Mei Li Nai‐Li Wang Xin‐Sheng Yao 《Magnetic resonance in chemistry : MRC》2010,48(1):38-43
Two new oxidized sterols 1 and 2 were obtained from the active fraction of a mangrove fungus Aspergillus awamori isolated from the soils around the mangrove plant Acrostichum speciosum. Their structures were elucidated using spectroscopic methods as 22E‐7α‐methoxy‐5α,6α‐epoxyergosta‐8(14),22‐dien‐3β‐ol (1) and 22E‐3β‐hydroxy‐5α,6α,8α,14α‐diepoxyergosta‐22‐en‐7‐one (2). The NMR data and complete assignments for both DMSO‐d6 and CDCl3 were given. Their cytotoxic activity against A549 cell line was evaluated. Furthermore, the detailed conformation analysis for ring B (cyclohexene oxide system) of sterol 1 was given on the basis of NOEs. The endo‐boat conformation was considered as the preferred conformation for ring B rather than half‐chair conformation. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
26.
The sterol composition of macromycete fungus Laetiporus sulphureus was analyzed by GC-MS. The fungus contained mainly C16 to C20 fatty acids, C16 to C24 fatty acid ethyl esters, and C28, C29,
and C30, Δ5, Δ7, and Δ5,7 conventional sterols, and in minor amounts Δ0 analogues with saturated and unsaturated side chains. Moreover, ergosterol peroxide and cerevisterol were identified. This
sterol pattern was compared with those of other members of the family Polyporaceae reported in the literature.
Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 170–172, March–April, 2009. 相似文献
27.
Chemical investigation of the cultures of a sponge-derived fungus Simplicillium sp. YZ-11 led to the isolation of a new minor diketopiperazine alkaloid cyclo-(2-hydroxy-Pro-Gly) (1) and a natural lactone (S)-dihydro-5-[(S)- hydroxyphenylmethyl]-2(3H)-furanone (2), together with five known ergostane-type sterols (3–7). Their structures were established based on extensive spectroscopic methods (1H and 13C NMR, 1H-1H COSY, HSQC and HMBC) and optical rotation analysis. 相似文献
28.
N. E. Eshmirzaeva N. K. Khidyrova M. Khodzhaeva L. G. Mezhlumyan Kh. M. Shakhidoyatov 《Chemistry of Natural Compounds》2005,41(4):451-453
Neutral substances, carbohydrates, and microelements from the aerial part of Silene viridiflora in addition to the protein content and its amino-acid composition were determined.
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Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 365–366, July–August, 2005. 相似文献
29.
A. R. Karimova S. G. Yunusova S. I. Maslennikov E. G. Galkin T. S. Yunusov V. V. Shereshovets M. S. Yunusov 《Chemistry of Natural Compounds》2000,36(6):560-564
Methyl and triterpenyl fatty-acid esters and triterpenic acids are isolated and identified from seeds ofViburnum opulus(Caprifoliaceae). The biological activity of pigments and proteins is determined 相似文献
30.