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1.
A New Asterosaponin from the Starfish Culcita novaeguineae 总被引:1,自引:0,他引:1
HaiFengTANG YangHuaYI LingLI PengSUN DaZhengZHOU BaoShuLIU 《中国化学快报》2005,16(5):619-622
A new asterosaponin named novaeguinoside A, along with a known saponin, asteronyl pentaglycoside sulfate, was isolated from the starfish Culcita novaeguineae. The new compound was identitied to be sodium 6α-O-{β-D-fucopyranosyl-(1→2)-β-D-fucopyranosyl-(1→4)-[β-D-quinovopyranosyl-(1→2)]-β-D-xylopyranosyl-(1→3)-[β-D-quinovopyranosyl}-5α-pregn-9(11)-en-20-one-3β-yl-sulfate by extensive spectral analysis and chemical evidence. 相似文献
2.
HaiYangLIU ChangXiangCHEN 《中国化学快报》2002,13(7):633-636
Two new C27 steroidal glycosides, named taccaoside A(1) and B(2), were isolated from the traditional Chinese herb Tacca plantaginea. The spectroscopic and chemical evidences revealed their structures to be 26-O-β-D-glucopyranosyl-(25R)-3β,26-dihydroxy furost-5,20-diene-3-O-[α-L-rhamnopyranosyl(1→2)]-[α-L-rhamnopyranosyl(1→3)]-β-D-glucopyranoside(1) and 26-O-β-D-glucopyranosyl-(25R)-3β,26-dihydroxy furost-5,20-diene-3-O-[α-L-rhamnopyranosyl-(1→2)]-[β-D-glucopyranosyl(1→3)-α-L-rhamnopyranosyl(1→3)]-β-D-glucopyranoside(2),respectively. 相似文献
3.
Two New C—21 Steroidal Glycosides from Cynanchum aurichulatum 总被引:2,自引:0,他引:2
Two new C-21 steroidal glycosides, cynanauriculoside I and cynanauriculoside Ⅱ, were isolated from the roots of Cynanchum aurichulatum. Their structures were established using spectroscopic methods including one and two-dimensional NMR. 相似文献
4.
Two new spirostanol glycosides named agamenoside A and B, ere isolated from the fermented leaves of Agave americana. Their structures were elucidated as (23S,25R)-5α-spirostan-3β,6α,23-triol 3-O-α-L-rhamnopyranosyl-(1→3)-β-D-glucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside(1) and (25R)-5α-spiro-stan-3β,6α-diol 3-O-β-D-glucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyra-nosyl-(1→4)-β-D-galactopyranoside(2) by a combination of chemical and spectral methods. 相似文献
5.
Cheng‐Xiong Liu Zhi‐yong Guo Yan‐Hong Xue Hong‐Yan Zhang Hong‐Qi Zhang Kun Zou Nian‐Yu Huang 《Magnetic resonance in chemistry : MRC》2012,50(4):320-324
Three new steroidal compounds with polyhydroxy groups, tupisteroide A–C (1–3), were obtained from the roots of Tupistra chinensis, together with one known compound (4) that was isolated from this plant for the first time. The structures of tupisteroide A–C were determined on the basis of one‐ and two‐dimensional NMR spectroscopy, including 1H–1H Correlation Spectroscopy, Heteronuclear Multiple Bond Correlation, and Heteronuclear Single Quantum Coherence experiments. The isolated compounds were evaluated for their cytotoxic activities against A549, HepG2, and CaSki cancer cell lines in vitro. Among them, compounds 1, 2, and 4 did not show significant inhibitory activity, but compound 3 showed cytotoxicity against A549 cancer cell lines with IC50 values of 25.0 μM. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
6.
Chemical fingerprint analysis and quantitative determination of steroidal compounds from Dioscorea villosa,Dioscorea species and dietary supplements using UHPLC‐ELSD 下载免费PDF全文
Bharathi Avula Yan‐Hong Wang Zulfiqar Ali Troy J. Smillie Ikhlas A. Khan 《Biomedical chromatography : BMC》2014,28(2):281-294
Ultra high‐performance liquid chromatography (UHPLC) with evaporative light scattering detection was used for the quantification of steroidal saponins and diosgenin from the rhizomes or tubers of various Dioscorea species and dietary supplements that were purported to contain Dioscorea. The analysis was performed on an Acquity UPLC? system with an UPLC? BEH Shield RP18 column using a gradient elution with water and acetonitrile. Owing to their low UV absorption, the steroidal saponins were observed by evaporative light scattering detection. The 12 compounds could be separated within 15 min using the developed UHPLC method with detection limits of 5–12 µg/mL with 2 μL injection volume. The analytical method was validated for linearity, repeatability, accuracy, limits of detection and limits of quantification. The relative standard deviations for intra‐ and inter‐day experiments were <3.1%, and the recovery efficiency was 97–101%. The total content of standard compounds was found to be in the ranges 0.01–14.5% and 0.9–28.6 mg daily intake for dry plant materials and solid commercial preparations, respectively. UHPLC–mass spectrometry with a quadrupole mass analyzer and ESI source was used only for confirmation of the identity of the various saponins. The developed method is simple, rapid and especially suitable for quality control analysis of commercial products. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
7.
Structures and Bioactivities of Steroidal Saponins Isolated from the Genera Dracaena and Sansevieria
Zaw Min Thu Sann Myint Oo Thinn Myat Nwe Hnin Thanda Aung Chabaco Armijos Faiq H. S. Hussain Giovanni Vidari 《Molecules (Basel, Switzerland)》2021,26(7)
The species Dracaena and Sansevieria, that are well-known for different uses in traditional medicines and as indoor ornamental plants with air purifying property, are rich sources of bioactive secondary metabolites. In fact, a wide variety of phytochemical constituents have been isolated so far from about seventeen species. This paper has reviewed the literature of about 180 steroidal saponins, isolated from Dracaena and Sansevieria species, as a basis for further studies. Saponins are among the most characteristic metabolites isolated from the two genera. They show a great variety in structural motifs and a wide range of biological activities, including anti-inflammatory, anti-microbial, anti-proliferative effects and, in most case, remarkable cytotoxic properties. 相似文献
8.
Oxidative cyclization of 5α-cholestan-6-one thiosemicarbazone (1), its 3β-chloro (2) and 3β-acetoxy (3) analogues with active manganese dioxide at room temperature afforded selectively the corresponding (6R)-spiro-1’,2’,4’-triazoline-3’-thiones 4—6. This synthesis has the advantages of mild reaction conditions, easy handling, easily available reagent and high yields. The products have been characterized by analytical and spectral data. 相似文献
9.
A. G. Shavva G. L. Starova S. I. Selivanov S. N. Morozkina 《Chemistry of Heterocyclic Compounds》2008,44(2):148-152
By X-ray crystallographic analysis and NMR spectroscopy it was demonstrated that the conformations of several D-homo-6-oxa-8α
analogs of steroidal estrogens are similar in the crystal and in solution. The distances between the hydrogen atoms in these
molecules, calculated by the ab initio and MM+ methods, correspond to the experimental data.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 202–207, February, 2008. 相似文献
10.
Three new steroidal saponins, Vernoniosides S1 ( 1 ), Vernoniosides S2 ( 2 ) and Vernoniosides S3 ( 3 ) were isolated from the stem of Vernonia cumingian. Their chemical structures were elucidated on the basis of MS, NMR spectroscopic and chemical analysis. Complete assignment of 1H and 13C NMR spectroscopic data were achieved by 1D and 2D NMR experiments (HMQC, HMBC, ROESY). Copyright © 2008 John Wiley & Sons, Ltd. 相似文献