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1.
A new compound,kudinoside LZ_2(1),was isolated from the leaves of Ilex kudincha.Its structure was elucidated by the combination of one- and two-dimensional NMR analysis,HR-ESI-MS,CD spectrum measurement and chemical evidences.  相似文献   

2.
One unusual triterpenoid derivative, ilekudinchoside E (1), was isolated from the leaves of Ilex kudincha. The structure was established by various spectroscopic techniques, including one‐ and two‐dimensional NMR, HRTOFMS and CD spectra. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

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A concise synthesis of a tetrasaccharide related to the cell-growth inhibitory triterpenoid saponin isolated from Schima noronhae is reported. A late stage 2,2,6,6-tetramethylpiperidinyloxy (TEMPO)-mediated oxidation of a primary hydroxyl group to carboxylic acid has been achieved under phase-transfer conditions. Stereoselective glycosylations were carried out using thioglycoside or glycosyl trichloroacetimidate activation using sulfuric acid immobilized on silica (H2SO4–silica) in conjunction with N-iodosuccinimide and alone, respectively.  相似文献   

5.
The Athabasca oil sand bitumen contains a homologous series of tricyclic terpanes containing 19–30 C atoms per molecule. The structure of the most abundant member, the C23 trycyclane, has now been elucidated.  相似文献   

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A novel alkaloid featuring a unique tetracyclic ring system was isolated from a marine actinobacterium.  相似文献   

7.
Concise synthesis of the glycone part (a pentasaccharide) of the anti-leishmanial triterpenoid saponin isolated from Maesa balansae is reported. A late-stage TEMPO-mediated oxidation of a primary hydroxyl group to carboxylic acid has been achieved under phase-transfer conditions. Glycosylations were performed either by thioglycoside or glycosyl trichloroacetimidate activation using sulfuric acid immobilized on silica (H2SO4-silica) in conjunction with N-iodosuccinimide and alone, respectively. H2SO4-silica was proved to be a better choice as promoter than conventional Lewis acid promoters such as TfOH or TMSOTf.  相似文献   

8.
Two new triterpenoid saponins, latifoloside I (1), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl 3beta,21alpha,28-trihydroxy-urs-12-ene 21-O-beta-D-glucopyranoside; latifoloside J (2), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl-3beta,21alpha-dihydroxy-ursolic acid 21-O-beta-D-glucopyranoside, along with two known compounds, latifoloside C (3) and latifoloside E (4), were isolated from the bark of Ilex latifolia THUNB. Structure assignments were established on the basis of spectroscopic data and chemical evidence.  相似文献   

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Phytochemical examination on the leaves of Ilex cornuta Lindl. (Aquifoliaceae) resulted in the isolation and identification of lupeol (I), 3β-hydroxylup-20(29)-en-30-al (II), oleanolic acid (III), and β-sitosterol-β-D-glucoside (IV).  相似文献   

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A novel terpenoid-related compound, stolonilactone (1), was isolated from the Okinawan soft coral Clavularia koellikeri. The structure of 1 was elucidated on the basis of spectroscopic analysis. A possible biogenesis of 1 through the [4 + 2]-cycloaddition of a trisnorsesquiterpenoid-type diene and a cembranolide-type dienophile is proposed.  相似文献   

13.
A concise synthesis of a tetrasaccharide related to the triterpenoid saponins Bellisoside has been accomplished from commercially available monosaccharides through rational protecting group manipulations and stereoselective glycosylations. For the glycosylation reactions, H2SO4–silica has been successfully used as an alternative to conventional Lewis acids such as TfOH or TMSOTf. The target tetrasaccharide has been synthesized in the form of its p-methoxyphenyl glycoside which leaves scope for further glyco-conjugate formation through the selective deprotection of p-methoxyphenyl glycoside followed by trichloroacetimidate chemistry.  相似文献   

14.
Penicillium citrium produces several fructose oligomers, namely kestose, neokestose, nystose, 1‐furanosylnystose and a novel pentasaccharide. The pentasaccharide consists of four fructoses and one glucose but its structure is different from that of 1‐furanosylnystose. Its complete structure was determined based on various two‐dimensional NMR experiments. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

15.
Three novel diterpenes were isolated from cultures of an unidentified marine-derived fungus. The structures of the compounds, phomactin I (1), 13-epi-phomactin I (2), and phomactin J (3) were determined by spectroscopic and X-ray crystallographic methods.  相似文献   

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Column chromatography of the n-butanol extract of the stem of Ardisia kivuensis (Myrsinaceae) led to the isolation of a new triterpenoid saponin, ardisikivuoside (1) {3-O-beta-D-xylopyranosyl-(1 --> 3)-beta-D-glucopyranosyl-(1 --> 4)-beta-D-xylopyranosyl-3beta-hydroxy-13beta,28-epoxyoleanan-16-oxo-30-al}. The structure was elucidated on the basis of spectral studies.  相似文献   

18.
A new triterpene saponin, catomentosaponin (1) and 11 known analogues (212) were isolated from the roots of Catunaregam tomentosa. The structures of 112 were determined on the basis of extensive NMR and MS data analysis. The sugar residues were identified by co-TLC and HPLC analysis after hydrolysis. All isolated compounds were evaluated for their cytotoxicity against KB and HeLa cell lines. Compound 2 showed moderate cytotoxicity against KB cell with IC50 value of 24.84 μM.  相似文献   

19.
Summary Triterpene glycosides have been isolated fromNaumburgia thyrsiflora (L.) Rchb. for the first time. It has been established that saponin A is a trioside of priverogenin A.Institute of Chemistry, Academy of Sciences of the Moldavian SSR. Vitebsk State Medical Institute. Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 364–366, May–June, 1975.  相似文献   

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