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1.
M. D. Alaniya N. Sh. Kavtaradze A. V. Skhirtladze M. G. Sutiashvili 《Chemistry of Natural Compounds》2011,47(3):377-381
New flavonoid oligosides were isolated from leaves and flowers of Astragalus falcatus Lam. It was found on the basis of chemical
transformations, UV, IR, PMR, 13 C NMR, HMBC, HSQC, 1D-TOCSY, and mass spectral properties that falcoside C had the structure quercetin 3-O-[β-D-glucopyranosyl(1 → 3)-α-Lrhamnopyranosyl(1 → 6)]-β-D-galactopyranoside 7-O-β-D-glucopyranoside; falcoside D, isorhamnetin 3-O-[β-D-xylopyranosyl(1 → 3)-α-L-rhamnopyranosyl(1 → 6)]-β-D-galactopyranoside 7-O-α-Lrhamnopyranoside. 相似文献
2.
Glucofructans from Saussurea lappa (Asteraceae) roots were studied. It was found that free fructose and oligomeric glucofructans (saccharose, 1-kestose, nystose,
1F-β-fructofuranosylnystose, and 1F-β-fructofuranosyl-1F-β-fructofuranosylnystose) were present. The dominant polymer Sl-GF (MW 51.4 kDa), which was a linear inulin-type glucofructan
consisting of β-(2 → 1)-bonded fructofuranose units, was isolated and characterized. The total content of glucofructans in Saussurea lappa roots was 476.97–578.27 mg/g. 相似文献
3.
Two spirostanol saponins, one of which was a new compound, were isolated among the steroidal glycosides of Allium cyrillii Ten. Bulbs. The structures of these glycosides were established using chemical and spectral analytical methods as β-D-glycopyranosyl-(1 → 2)-[β-D-xylopyranosyl-(1 → 3)]-β-D-glucopyranosyl-(1 → 4)β-D-galactopyranosyl-(1 → 3)-(25R)-5α-spirostan-2α,3β-diol and β-D-glucopyranosyl-(1 → 2)-[4-O-(3hydroxy-3-methylglutaryl)-β-D-xylopyranosyl-(1 → 3)]-β-D-glucopyranosyl-(1 → 4)-β-D-galactopyranosyl(1 → 3)-(25R)-5α-spirostan-2α,3β-diol. 相似文献
4.
A new triterpene cycloartane glycoside called askendoside K was isolated from roots of Astragalus taschkendicus Bunge (Leguminosae). The structure of this glycoside was established using chemical and biochemical transformations and spectral
data. Askendoside K was a bisdesmoside of cycloorbigenin C and had the structure 23R,24R-cycloartan-3β,6α,16β,23,24,25-hexaol 3-O-[(α-L-arabinopyranosyl)(1 → 2)-β-D-xylopyranoside],23-O-[(β-D-glucuronopyranosyl)(1 → 2)-β-D-glucopyranoside]. 相似文献
5.
Changling Duan Yi Wang Xiaofeng Ma Yong Jiang Jianxun Liu Pengfei Tu 《Chemistry of Natural Compounds》2012,48(4):613-615
A new furostanol glycoside, named ophiopogonin J (1), was isolated from the fibrous root of Ophiopogon japonicas. The structure of the compound was established as (25R)-26-[(O-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosyl)]-20α -hydroxyfurost-5, 22-diene-3-O-α-L-rhamnopyranosyl-(1 → 2)-[β-D-xylopyranosyl(1 → 4)]-β-D-glucopyranoside on the basis of spectroscopic methods, including HR-ESI-MS and 1D and 2D NMR experiments. 相似文献
6.
R. P. Gorshkova V. V. Isakov O. I. Nedashkovskaya E. L. Nazarenko 《Chemistry of Natural Compounds》2011,46(6):837-840
A capsular polysaccharide (CPS) containing D-galactosamine uronic acid and D-alanine was isolated from a culture of the marine
proteobacterium Microbulbifer sp. KMM 6242. 2D NMR spectroscopy showed that the CPS is a homopolymer of 2-acetamido-2-deoxy-N-(D-galacturonyl)-D-alanine with the structure →4)-β-D-GalpNAcA6(D-Ala)-(1→. An O-specific polysaccharide containing D-ribose
and D-galactose was isolated from the cell-membrane lipopolysaccharide. 1D and 2D NMR spectroscopy established the structure
of the disaccharide repeating unit of the polysaccharide as →3)-β-D-Ribf-(1→4)-β-D-Galp-(1→. 相似文献
7.
M. R. Maisashvili Dzh. K. Kuchukhidze V. S. Kikoladze L. N. Gvazava 《Chemistry of Natural Compounds》2012,48(1):86-90
Two new steroidal glycosides were isolated by fractionation of total extracted substances from inflorescences and flower stalks
of Allium rotundum (Alliaceae). The structures were determined on the basis of chemical transformations, physical constants,
and spectral data as 26-O-β-D-glucopyranosyl-(25R)-5α-furostan2α,3β,22α,26-tetraol 3-O-β-D-glucopyranosyl-(1 → 2)[β-D-xylopyranosyl-(1 → 3)]-β-D-glucopyranosyl(1 → 4)-β-D-galactopyranoside (2) and (25R)-5α-spirostan-2α,3β-diol 3-O-β-D-glucopyranosyl-(1 → 3)-βD-glucopyranosyl-(1 → 2)-[β-D-xylopyranosyl-(1 → 3)]-β-D-glucopyranosyl-(1 → 4)-β-D-galactopyranoside (3). 相似文献
8.
Determination of the structure of heparin-derived oligosaccharides by 1H NMR is challenging because resonances for all but the anomeric protons cover less than 2 ppm. By taking advantage of increased
dispersion of resonances for the anomeric H1 protons at low pD and the superior resolution of band-selective, homonuclear-decoupled (BASHD) two-dimensional 1H NMR, the primary structure of the heparin-derived octasaccharide ∆UA(2S)-[(1 → 4)-GlcNS(6S)-(1 → 4)-IdoA(2S)-]3-(1 → 4)-GlcNS(6S) has been determined, where ∆UA(2S) is 2-O-sulfated ∆4,5-unsaturated uronic acid, GlcNS(6S) is 6-O-sulfated, N-sulfated β-d-glucosamine and IdoA(2S) is 2-O-sulfated α-l-iduronic acid. The spectrum was assigned, and the sites of N- and O-sulfation and the conformation of each uronic acid residue were established, with chemical shift data obtained from BASHD-TOCSY
spectra, while the sequence of the monosaccharide residues in the octasaccharide was determined from inter-residue NOEs in
BASHD-NOESY spectra. Acid dissociation constants were determined for each carboxylic acid group of the octasaccharide, as
well as for related tetra- and hexasaccharides, from chemical shift–pD titration curves. Chemical shift–pD titration curves
were obtained for each carboxylic acid group from sub-spectra taken from BASHD-TOCSY spectra that were measured as a function
of pD. The pK
As of the carboxylic acid groups of the ∆UA(2S) residues are less than those of the IdoA(2S) residues, and the pK
As of the carboxylic acid groups of the IdoA(2S) residues for a given oligosaccharide are similar in magnitude. Relative acidities
of the carboxylic acid groups of each oligosaccharide were calculated from chemical shift data by a pH-independent method. 相似文献
9.
A. A. Kicha N. V. Ivanchina T. T. T. Huong A. I. Kalinovsky P. S. Dmitrenok P. Q. Long 《Russian Chemical Bulletin》2010,59(11):2133-2136
A new minor asterosaponin (20S)-6-O-{β-d-fucopyranosyl-(1→2)-[β-d-fucopyranosyl-(1→4)-β-d-quinovopyranosyl-(1→2)]-β-d-quinovopyranosyl-(1→3)-β-d-quinovopyranosyl}-3β,6α,20-trihydroxycholest-9(11)-en-23-one 3-sulfate (archasteroside C) was isolated from the starfish
Archaster typicus collected in shallow coastal waters of Vietnam. The structure of archasteroside C was determined by 2D NMR spectroscopy and
electrospray ionization (ESI) tandem mass spectrometry. 相似文献
10.
A 66-kDa thermostable family 1 Glycosyl Hydrolase (GH1) enzyme with β-glucosidase and β-galactosidase activities was purified
to homogeneity from the seeds of Putranjiva roxburghii belonging to Euphorbiaceae family. N-terminal and partial internal amino acid sequences showed significant resemblance to plant GH1 enzymes. Kinetic
studies showed that enzyme hydrolyzed p-nitrophenyl β-d-glucopyranoside (pNP-Glc) with higher efficiency (K
cat/K
m = 2.27 × 104 M−1 s−1) as compared to p-nitrophenyl β-d-galactopyranoside (pNP-Gal; K
cat/K
m = 1.15 × 104 M−1 s−1). The optimum pH for β-galactosidase activity was 4.8 and 4.4 in citrate phosphate and acetate buffers respectively, while
for β-glucosidase it was 4.6 in both buffers. The activation energy was found to be 10.6 kcal/mol in the temperature range
30–65 °C. The enzyme showed maximum activity at 65 °C with half life of ~40 min and first-order rate constant of 0.0172 min−1. Far-UV CD spectra of enzyme exhibited α, β pattern at room temperature at pH 8.0. This thermostable enzyme with dual specificity
and higher catalytic efficiency can be utilized for different commercial applications. 相似文献
11.
B. V. Tabidze N. A. Tabatadze G. E. Dekanosidze R. Elias R. Faure 《Chemistry of Natural Compounds》2009,45(5):660-663
Nine pure glycosides were isolated from total saponins of Cyclamen adzharicum Pobed. (Primulaceae). The total chemical structure of cyclamen F, 3β-O-[β-D-Xylp(1→2)]-[β-D-Glcp(1→2)]-(β-D-Glcp(1→4)-α-L-Arap)-16α-hydroxy-13,28-epoxy-30,30-dibutoxyolean, was elucidated using modern physicochemical and spectral
methods (NMR, 1H, 13C, HMBC, HMQC, DEPT, COSY, MS). A glycoside with the cyclamen F chemical structure has not been reported and, therefore, is
a new organic compound. 相似文献
12.
Identification of a new flavone glycoside from <Emphasis Type="Italic">Codonopsis nervosa</Emphasis>
Xian-li Zhou Qiang Fan Shuai Huang Cui-juan Wang You-song Wang 《Chemistry of Natural Compounds》2012,47(6):888-890
A new flavone glycoside, luteolin 7-O-[(6″′-caffeoyl)-β-D-glucopyranosyl-(1 → 6)]-β-D-glucopyranoside (1), was isolated from Codonopsis nervosa, along with three other known compounds, luteolin 7-O-β-D-glucopyranoside (2), luteolin 7-O-gentiobioside (3), and tangshenoside VI (4). Their structures were determined on the basis of 1D and 2D NMR, IR, and HR-ESI-MS. 相似文献
13.
Chun-Chao Zhao Jian-Hua Shao Chun-Jie Zhao Xian Li 《Chemistry of Natural Compounds》2011,47(4):545-546
A new flavonoid glycoside, an apigenin 7-O-(3,4-di-O-acetyl)-α-L-rhamnopyranosyl-(1 → _6)-β-D- glucopyranoside (1), was isolated from the 95% ethanol extract of Galium verum L. Its structure was elucidated by spectroscopic analysis. 相似文献
14.
R. P. Gorshkova V. V. Isakov V. A. Denisenko E. L. Nazarenko E. P. Ivanova L. S. Shevchenko 《Chemistry of Natural Compounds》2008,44(5):549-551
The O-specific polysaccharide of Alteromonas addita type strain KMM 3600T is constructed of trisaccharide repeat units containing L-rhamnose, D-glucose, and D-galactose. It
was established that the O-specific polysaccharide consists of trisaccharide repeat units with the structure →3)-α-D-Galp-(1→3)-α-L-Rhap-(1→3)-α-D-Glcp-(1→ based on monosaccharide analysis, Smith degradation, PMR and 13C NMR spectroscopy, and two-dimensional COSY, HSQC, and HMBC.
Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 445–447, September-October, 2008. 相似文献
15.
M. Z. Getiya M. A. Gabelaya V. D. Mshvildadze A. Pichette S. Lavoie G. E. Dekanosidze 《Chemistry of Natural Compounds》2011,47(5):764-766
Glycosides H and I, the structures of which were established by modern physicochemical analytical methods (PMR, 13C NMR, COSY, TOCSY, HMBC, MS) and acid-base hydrolysis, were isolated from the purified total saponins from fruit of Phytolacca americana containing at least 10 triterpene glycosides by rechromatography of enriched fractions over a column of silica gel. Glycoside
H was a bidesmoside of phytolaccageninic acid, which was isolated earlier from cell culture of Phytolacca acinosa. Glycoside
I was 3-O-(β-D-xylopyranosyl-(1 → 3)-β-D-galactopyranosyl-(1 → 3)- β -D-xylopyranosyl)-28-O- β -D-glucopyranosyl phytolaccagenin, which was isolated by us for the first time. 相似文献
16.
Dicko MH Searle-van Leeuwen MJ Traore AS Hilhorst R Beldman G 《Applied biochemistry and biotechnology》2001,94(3):225-241
The leaves of Boscia senegalensis are traditionally used in West Africa in cereal protection against pathogens, pharmacologic applications, and food processing.
Activities of α-amylase, β-amylase, exo-(1→3, 1→4)-β-d-glucanase, and endo-(1→3)-β-d-glucanase were detected in these leaves. The endo-(1→3)-β-d-glucanase (EC3.2.1.39) was purified 203-fold with 57% yield. The purified enzyme is a nonglycosylated monomeric protein with
a molecular mass of 36 kDa and pI≥10.3. Its optimal activity occurred at pH 4.5 and 50°C. Kinetic analysis gave V
max, k
cat
, and K
m
values of 659 U/mg, 395 s−1, and 0.42 mg/mL, respectively, for laminarin as substrate. The use of matrix-assisted laser desorption ionization time-of-flight
mass spectrometry and high-performance liquid chromatography revealed that the enzyme hydrolyzes not only soluble but also
insoluble (1→3)-β-glucan chains in an endo fashion. This property is unusual for endo-acting (1→3)-β-d-glucanase from plants. The involvement of the enzyme in plant defense against pathogenic microorganisms such as fungi is
discussed. 相似文献
17.
The new flavone glycoside schachristanoside was isolated from the aerial part of Scutellaria schachristanica Zuz. (Lamiaceae). Spectral data and chemical transformations found that schachristanoside had the structure chrysin-7-O-[α-L-arabinopyranosyl-(1 → 6)]-β-D-glucopyranoside. 相似文献
18.
A new triterpene glycoside of the cycloartane series that was called askendoside H was isolated from roots of Astragalus taschkendicus
Bunge (Leguminosae). Its structure was elucidated based on chemical transformations and spectral data. Askendoside H was a
bisdesmoside of cycloorbigenin C, 23R,24Rcycloartan-3β,6α,16β,23,24,25-hexaol 3-O-[(α-L-arabinopyranosyl)(1 → 2)-β-D-xylopyranoside] 23-O-βD-glucopyranoside. 相似文献
19.
Mixtures of diblock co-oligomers of tri-O-methylated and unmodified cello-oligosaccharides have been found to be amphiphilic, as reported before. In order to clarify
their accurate amphiphilic property, diblock co-oligomers of tri-O-methylated and unmodified cello-oligosaccharides with monodispersity, methyl β-d-glucopyranosyl-(1→4)-2,3,6–tri-O-methyl-β-d-glucopyranosyl-(1→4)-2,3,6–tri-O-methyl-β-d-glucopyranosyl-(1→4)-2,3,6-tri-O-methyl-β-d-glucopyranosyl-(1→4)-2,3,6-tri-O-methyl-d-glucopyranoside (1, pentamer), methyl β-d-glucopyranosyl-(1→4)- β-d-glucopyranosyl-(1→4)-2,3,6-tri-O-methyl-β-d-glucopyranosyl-(1→4)-2,3,6-tri-O-methyl-β-d-glucopyranosyl-(1→4)-2,3,6-tri-O-methyl-β-d-glucopyranosyl-(1→4)-2,3,6-tri-O-methyl-d-glucopyranoside (2, hexamer), and methyl β-d-glucopyranosyl-(1→4)-2,3,6-tri-O-methyl-β-d-glucopyranosyl-(1→4)- 2,3,6-tri-O-methyl-d-glucopyranoside (3, trimer) were synthesized independently. These compounds had higher surface activities compared to the mixture of diblock
co-oligomers of tri-O-methylated and unmodified cello-oligosaccharides and commercially available methylcellulose (MC) SM-4. This paper describes
the methods of synthesis of these compounds, and the influence of amphiphilic character on their surface activity. A new class
of carbohydrate-based nonionic surfactant without long alkyl chain was discovered. 相似文献
20.
Lin Zhang Baoguo Li Jingkui Tian Lizhen Xu Shilin Yang 《Chemistry of Natural Compounds》2007,43(5):567-570
Two new saponins were isolated from an ethanol extract of the whole plants of Lysimachia davuria. The new saponins were respectively characterized as 3-O-{β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→4)]-α-L-arabinopyranosyl}-3β,28-dihydroxyolean-12-en-30-oic acid-O-[β-D-xylopyranosyl-(1→2)-β-D-glucopyranosyl]-ester (1) and 3-O-{ β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→4)]-α-L-arabinopyranosyl}-3β,28-dihydroxyolean-12-en-30-oic acid-O-β-D-glucopyranosyl-ester (2). Their structures were determined by 1D, 2D NMR and MS techniques.
Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 466–468, September–October, 2007. 相似文献