共查询到20条相似文献,搜索用时 796 毫秒
1.
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
2.
Two new polyhydroxysteroids and five new glycosides were isolated from the starfishCeramaster patagonicus and their structures were elucidated: 5α-cholestane-3β,6α,15β,16β,26-pentol, (22E)-5α-cholest-22-ene-3β,6α,8,15α,24-pentol, (22E)-28-O-[O-(2-O-methyl-β-d-xylopyranosyl)-(1→2)-β-d-galactofuranosyl]-24-hydroxymethyl-5α-cholest-22-ene-3β,4β, 6α,8,15β,16β,28-heptol (ceramasteroside C1), (22E)-28-O-[O-(2,4-di-O-methyl-β-d-xylopyranosyl)-(1→2)-β-d-galactofuranosyl]-24-hydroxymethyl-5α-cholest-22-ene-3β, 6α,8,15β,16β,28-hexol (ceramasteroside C2), (22E)-28-O-[O-methyl-β-d-xylopyranosyl)-(1→2)-β-d-galactofuranosyl]-24-hydroxymethyl-5α-cholest-22-ene-3β,6α,8,15β,16β 28-hexol (eramasteroside C3), (22E)-28-O-[O-(2-O-methyl-β-d-xylopyranosyl)-(1→2)-β-d-galactofuranosyl]-24-methyl-5α-cholest-22-ene-3β,4β,6α,8, 15β, 26-hexol (ceramasteroside C4), and (22E)-28-O-[O-(2-O-methyl-β-d-xylopyranosyl)-(1→2)-β-d-xylopyranosyl]-5α-cholest-22-ene-3β,6α,8,15β,24-pentol (ceramasteroside C5)). Three known polyhydroxysteroids (24-methylene-5α-cholestane-3β,6α,8,15β,16β,26-hexol, 5α-cholestane-3β,6α,8,15β,16β,26-hexol,
and 5α-cholestane-3β,6β,15α,16β,26-pentol) were also isolated.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 190–195, January, 1997. 相似文献
3.
Triblock cooligomers consisting of tri-O-methyl-glucopyranosyl and unmodified glucopyranosyl residues, methyl 2,3,4,6-tetra-O-methyl-β-d-glucopyranosyl-(1 → 4)-2,3,6-tri-O-methyl-β-d-glucopyranosyl-(1 → 4)-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-α-d-glucopyranoside (1: ABA triblock cooligomer; DS = 2.1) and 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-β-d-glucopyranosyl-(1 → 4)-d-glucopyranose (2: BAB triblock cooligomer; DS = 1.8) were prepared. Compound 1 dissolved both in distilled water and chloroform but compound 2 dissolved in distilled water not in chloroform, though compounds 1 and 2 consist of 4 tri-O-methyl-glucopyranosyl and 2 unmodified anhydro glucopyranosyl units. 相似文献
4.
E. V. Sukhova A. V. Dubrovskii Yu. E. Tsvetkov N. E. Nifantiev 《Russian Chemical Bulletin》2007,56(8):1655-1670
2-Aminoethyl 3,6-di-O-sulfo-β-D-glucopyranosyl-(1→3)-β-D-galactopyranosyl-(1→4)-2-acetamido-2-deoxy-β-D-glucopyranoside, which is the sulfo-mimetic of the antigenic trisaccharide HNK-1, and the corresponding monosulfates, viz., 2-aminoethyl 3-O-sulfo-and 2-aminoethyl 6-O-sulfo-β-D-glucopyranosyl-(1→3)-β-D-galactopyranosyl-(1→ 4)-2-acetamido-2-deoxy-β-D-glucopyranosides, were synthesized. 2-Azidoethyl 2,4-di-O-benzoyl-β-D-glucopyranosyl-(1→3)-2,4,6-tri-O-benzoyl-β-D-galactopyranosyl-(1→ 4)-2-acetamido-3,6-di-O-benzyl-2-deoxy-β-D-glucopyranoside served as the common precursor for the sulfated trisaccharides. This compound was synthesized according to
the [2+1] pattern from monosaccharidic precursors: 3,6-di-O-acetyl-2,4-di-O-benzoyl-D-glucopyranosyl trichloroacetimidate, allyl 2-O-benzoyl-4,6-O-benzylidene-β-D-galactopyranoside, and 2-azidoethyl 2-acetamido-3,6-di-O-benzyl-2-deoxy-β-D-glucopyranoside. The structures of the glycosyl donors and glycosylation conditions were optimized for the efficient synthesis
of the glucosyl-β-(1→3)-galactose disaccharide block and its subsequent transformation into the target trisaccharide sequence.
Dedicated to Academician V. A. Tartakovsky on the occasion of his 75th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1593–1607, August, 2007. 相似文献
5.
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
6.
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
7.
Abronina P. I. Galkin K. I. Backinowsky L. V. Grachev A. A. 《Russian Chemical Bulletin》2009,58(2):457-467
Block synthesis of a fully benzoylated derivative of the pentasaccharide α-d-Manp-(1→3)-α-d-Manp-(1→2)-α-d-Manp-(1→2)-α-d-Manp-(1→2)-α-d-Manp-SCH2CH2CO2Me, the glycoside of the repeating unit of the O-antigenic polysaccharide of the bacterium Klebsiella pneumoniae O3, was performed. 相似文献
8.
Hiroshi Kamitakahara Kaoru Murata-Hirai Yoshimasa Tanaka 《Cellulose (London, England)》2012,19(1):171-187
Bioimaging is a key to understanding immune responses, cell differentiation, and development. Quantum dots (QDs) conjugated
with monoclonal antibodies and other biomolecules are currently utilized for flow cytometry and immunohistochemistry, but
monoclonal antibody–QD complexes are of limited use when cell surface markers are not available. In this study, we synthesized
novel amphiphilic blockwise alkylated tetrasaccharides and developed a simple method for labeling a wide variety of live cells
with organic QDs encapsulated with these carbohydrates. The novel amphiphilic blockwise alkylated tetrasaccharides were as
follows: 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-d-glucopyranoside (1), methyl β-d-galactopyranosyl-(1 → 4)-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), ethyl β-d-glucopyranosyl-(1 → 4)-β-d-glucopyranosyl-(1 → 4)-2,3,6-tri-O-ethyl-β-d-glucopyranosyl-(1 → 4)-2,3,6-tri-O-ethyl-d-glucopyranoside, (3), and ethyl β-d-galactopyranosyl-(1 → 4)-β-d-glucopyranosyl-(1 → 4)-2,3,6-tri-O-ethyl-β-d-glucopyranosyl-(1 → 4)-2,3,6-tri-O-ethyl-d-glucopyranoside (4). The newly synthesized blockwise alkylated tetrasaccharides spontaneously assembled into micelle-like particles, in which
the hydrophobic moiety of the blockwise alkylated tetrasaccharides played an important role. They were less toxic to human
cells than octyl β-d-glucopyranoside, a commonly used amphiphilic glucoside. Flow cytometry and confocal laser scanning microscopy revealed that
the blockwise alkylated tetrasaccharide–organic QD complexes were stably attached to live cells. The affinity of compounds
1 and 2 to the live cell surface was slightly higher than that of compounds 3 and 4. Because the preparation of these carbohydrate–QD
complexes is simple and does not require sophisticated equipment, and because the complexes can be autonomously attached to
a wide spectrum of cell lines, they can be used as cell labeling reagents in biomedical studies. 相似文献
9.
Extraction and characterization of native heteroxylans from delignified corn stover and aspen 总被引:1,自引:0,他引:1
Radnaa Naran Stuart Black Stephen R. Decker Parastoo Azadi 《Cellulose (London, England)》2009,16(4):661-675
Dimethylsulfoxide-solubilized polysaccharides from delignified corn stover and aspen were characterized. The biomass was delignified
by two different techniques; a standard acid chlorite and a pulp and paper QPD technique comprising chelation (Q), peroxide
(P), and acid-chlorite (D). Major polysaccharides in all fractions were diversely substituted xylan. Xylan acetylation was
intact after chlorite delignification and, as expected, xylan from QPD-delignified fraction was de-acetylated by the alkaline
peroxide step. The study of DMSO-extractable xylans from chlorite-delignified biomass revealed major differences in native
acetylation patterns between corn stover and aspen xylan. Xylan from cell walls of corn stover contains 2-O- and 3-O-mono-acetylated xylan and [MeGlcA-α-(1 → 2)][3-OAc]-xylp units. In addition, aspen xylan also contains 2,3-di-O-acetylated xylose. 1,4-β-d-xylp residues substituted with MeGlcA at O-2 position are absent in chlorite-delignified aspen xylan. Sugar composition in accord with NMR-spectroscopic data indicated
that corn stover xylan is arabinosylated while aspen xylan is not. We have shown that corn stover xylan has similar structure
with xylans from other plants of Poales order. No evidence was found to indicate the presence of 1,4-β-d-[MeGlcA-α-(1 → 2)][Ara-α-(1 → 3)]-xylp in corn stover xylan fractions. 相似文献
10.
D. Zeković M. Radulović A. Nastasović M. M. Vrvić D. Jakovljević G. Kogan 《Chemical Papers》2006,60(3):243-248
The structure of the cell wall glucan isolated from the industrial strain of Saccharomyces cerevisiae was characterized as to be composed of a linear (1→3)-β-D-glucan chain with single β-D-glucopyranosyl residues attached to every ninth backbone unit by (1→6)-glycosidic linkages. Mild oxidation of this β-D-glucan with a dimethyl sulfoxide—acetic anhydride reagent yielded an “oxidized” glucan with aldehyde groups introduced at
C-6 and carbonyl oxygens located at C-2 and C-4 of the glucopyranosyl rings. The conversion of the oxidized glucan into the
polyoxime was used to study the progress of oxidation and to establish the carbonyl groups distribution in this new reactive
polysaccharide derived from baker’s yeast cell wall. 相似文献
11.
Yajuan Xu Tunhai Xu Yue Liu Shengxu Xie Yunshan Si Tonghua Liu Dongming Xu 《Chemistry of Natural Compounds》2010,46(2):242-245
The structures of five furostanol glycosides (1–5), of which the 26-O-β-D-glucopyranosyl-(25S),5α-furost20(22)-en-12-one-2α,3β,26-triol-3-O-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside (1) was new, from the leaves of Tribulus terrestris L. were established using chemical and NMR spectroscopic methods. 相似文献
12.
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
13.
P. I. Abronina L. V. Backinowsky A. A. Grachev S. L. Sedinkin N. N. Malysheva 《Russian Chemical Bulletin》2005,54(5):1287-1293
Methyl 2,4-di-O-benzoyl-α-D-mannopyranoside was used as a key intermediate in the synthesis of 3,6-branched mannopentaoside bearing one terminal D-[1-13C]mannopyranose residue, viz., methyl 6-O-[3,6-di-O-(α-D-mannopyranosyl)-α-D-mannopyranosyl)-3-O-{α -D-[1-13C]mannopyranosyl}-α-D-mannopyranoside.
Dedicated to Academician N. K. Kochetkov on the occasion of his 90th birthday.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1250–1255, May, 2005. 相似文献
14.
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
15.
A new steroid glycoside was isolated from leaves of Digitalis ciliata (Scrophulariaceae) by fractionation of the total extracted substances. Its structure was determined as (25R)-5α-spirostan-3β-ol 3-O-β-D-glucopyranosyl-(1→3)[β-D-fucopyranosyl-(1→2)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside based on chemical transformations,
physical constants, and spectral data.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 135–137, March–April, 2007. 相似文献
16.
N. V. Ivanchina T. V. Malyarenko A. A. Kicha A. I. Kalinovskii P. S. Dmitrenok 《Russian Chemical Bulletin》2008,57(1):204-208
Nine steroidal compounds including three new steroidal glycosides, viz., sodium (24S)-3,24-di-O-(β-D-xylopyranosyl)-5α-cholestane-3β,6β,8,15α,24-pentol 15-sulfate (fuscaside A), (24S)-3,24-di-O-(β-D-xylopyranosyl)-5α-cholestane-3β,6β,8,15α,24-pentol (fuscaside B), and (22E,24R)-24-O-(β-D-xylopyranosyl)-5α-cholest-22-ene-3β,6α,8,15β,24-pentol (desulfated minutoside A); three previously known glycosides, viz., distolasterosides D1 and D2 and pycno-podioside A; two previously known polyhydroxysteroids, viz., 5α-cholestane-3β,6α,8,15β,16β,26-hexaol and 5α-cholestan-3β,4β,6α,7⇇8,15β,16β,26-octol; and the known sodium 24,25-dihydro-marthasterone
3-sulfate were isolated from the Far-Eastern starfish Lethasterias fusca. The structures of these compounds were elucidated by NMR spectroscopy and mass spectrometry.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 196–200, January, 2008. 相似文献
17.
Christakopoulos P Katapodis P Hatzinikolaou DG Kekos D Macris BJ 《Applied biochemistry and biotechnology》2000,87(2):127-133
An α-l-arabinofuranosidase from Fusarium oxysporum F3 was purified to homogeneity by a two-step ion exchange intercalated by a gel filtration chromatography. The enzyme had
a molecular mass of 66 kDa and was optimally active at pH 6.0 and 60°C. It hydrolyzed aryl α-l-arabinofuranosides and cleaved arabinosyl side chains from arabinoxylan and arabinan. There was a marked synergistic effect
between the α-l-arabinofuranosidase and an endo-(1 →4)-β-d-xylanase produced by F. oxysporum in the extensive hydrolysis of arabinoxylan. 相似文献
18.
Wen-Juan Liang Qing-Yun Ma He-Zhong Jiang Jun Zhou Jie Pang You-Xing Zhao 《Chemistry of Natural Compounds》2012,47(6):935-939
A new oleane-type triterpene oligoglycoside, hederagenin 3-O-(3-O-acetyl-β-D-xylopyranosyl)-(1→3)-α-L-arabinopyranoside (2), together with four known compounds, hederagenin (1), hederagenin 3-O-(4-O-acetyl-α-L-arabinopyranosyl)-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranoside (3), hederagenin 3-O-α-L-arabinopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranoside (4), hederagenin 3-O-β-D-glucopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→4)-β-D-xylopyranoside (5), was isolated from the hull of Nephelium lappaceum. All the isolates were obtained from the hull of rambutan for the first time. 相似文献
19.
Methyl iodide activated stereospecific α-mannosylations utilising 2-pyridyl-1-thiomannopyranoside derivatives (2,3,4) as donors
and suitably protected myo-inositol derivatives (1,25,27,29) as acceptors to prepare 2-0-α-D-mannopyranosyl-6-[O-α-D-mannopyranosyl-(1–6)-O-α-D-mannopyranosyl-(l-6)-O-α-D-mannopyranosyl]-D-myo-inositol derivative (31) is described.
IICT Commun. No. 3355 相似文献
20.
D. A. Panov V. I. Grishkovets V. V. Kachala A. S. Shashkov 《Chemistry of Natural Compounds》2006,42(1):49-54
Thirteen known glycosides of hederagenin and oleanolic acid and the three new triterpene glycosides of oleanolic acid-28-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester 3-O-β-D-glucopyranosyl-(1→4)-O-β-D-xylopyranosyl-(1→ 3)-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranoside of oleanolic acid and the 28-O-α-L-rhamnopyranosyl-(1→4)-O-6-O-acetyl-β-D-glucopyranosyl-(1→ 6)-O-β-D-glucopyranosyl esters 3-O-β-D-xylopyranosyl-(1→3)-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranoside of oleanolic acid and 3-O-β-D-glucopyranosyl-(1→4)-O-β-Dxylopyranosyl-(1→3)-O-α-L-rhamnopyranosyl-(1→ 2)-O-α-L-arabinopyranoside of oleanolic acid were isolated from leaves of Kalopanax septemlobum var. typicum introduced to Crimea.
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Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 40–43, January–February, 2006. 相似文献