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1.
Silvana L. Giudicessi M. Kaniz Fatema Hiroshi Nonami Rosa Erra-Balsells 《Journal of the American Society for Mass Spectrometry》2010,21(9):1526-1529
The effect of Ca2+ (and Mg2+) and the disodium salt of ethylenediaminetetraacetic acid (EDTA), a well known Ca2+ (and Mg2+) chelating agent, on the volatilization/ionization of carbohydrates by using electrospray ionization mass spectrometry has
been studied. Model compounds such as maltoses (maltose to maltoheptaose), β-cyclodextrins (β-cyclodextrin, methyl-β-cyclodextrin,
heptakis(2,6-di-O-methyl)-β-cyclodextrin, heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin, and 2-hydroxypropyl-β-cyclodextrin)
and fructans (sucrose, 1-ketose, nystose, and 1F-fructofuranosylnystose) were used. 相似文献
2.
G. V. Shevchuk Yu. S. Vollerner A. S. Shashkov M. B. Gorovits V. Ya. Chirva 《Chemistry of Natural Compounds》1991,27(6):706-711
Two new glycosides which have been called nolinofurosides G(I) and H(III), have been isolated from the leaves ofNolina microcarpa. Nolinofuroside G is the sodium salt of 26-β-D-glucofuranosyloxy-(25S)-furost-5,20(22)-diene-1β, 3β-diol 1-sulfate, and nolinofuroside
H is the sodium salt of 1-β-D-fucopyranosyloxy-26-β-D-glucopyranosyloxy-(25S)-furost-5,20(22)-dinen-1β-3β-ol 3-sulfate.
M. V. Frunze Simferopol' State University. Institute of the Chemistry of Plant Substances, Uzbek. Academy of Sciences, Tashkent.
Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 801–806, November–December, 1991. 相似文献
3.
Xiao-Xiang Li Jun-Wen Wang Yu-Jing Guo Ling-Hong Kong Jing-Hao Pan 《Journal of inclusion phenomena and macrocyclic chemistry》2007,58(3-4):307-315
In phosphate buffer solution of pH5.4, the interaction of meso-tetrakis(2-thienyl)porphyrin(H2TTP) and Cu-meso-tetrakis(2-thienyl)porphyrin(Cu-TTP) with α-cyclodextrin(α-CD), β-CD, γ-CD, heptakis(2,3,6-tri-O-methyl)-β-CD(TM-β-CD)
has been studied by means of UV-vis, fluorescence and 1HNMR spectroscopy, respectively. The H2TTP and Cu-TTP can form 1:2 inclusion complexes with TM-β-CD and 1:1 inclusion complexes with the other three cyclodextrins.
In this paper, the inclusion constants (K) of H2TTP and Cu-TTP for the formation of the inclusion complexes have been estimated from the changes of absorbance and fluorescence
intensity in phosphate buffer solution. The inclusive capabilities of different kinds of cyclodextrins are compared. The result
shows that the inclusion ability of α-CD with H2TTP and Cu-TTP is the strongest among the three native CDs. The inclusion ability of modified β-CD with H2TTP and Cu-TTP is stronger, compared to the native β-CD, which indicates that the capacity matching plays a crucial role in
the inclusion procedure except for the hydrophobic effect. In addition 1HNMR spectra supports the inclusion conformation of the TM-β-CD-Cu-TTP inclusion complex, indicating the interaction mechanism
of inclusion processes. 相似文献
4.
Antonio Di Marino Francisco Mendicuti 《Journal of inclusion phenomena and macrocyclic chemistry》2007,58(3-4):295-305
Molecular mechanics (MM) and Molecular dynamics (MD) calculations were applied to study the complexation of 2-Methyl naphthalenecarboxylate
(2MN) and 2-hydroxypropyl -α-, -β-, and γ-cyclodextrins (HPCDs) in the presence of water. Results showed that 1:1 complexes
of 2MN with modified cyclodextrins are stable and that the non-bonded van der Waals interactions are mainly responsible for
the complexation. Theoretical results are in good agreement with fluoresence results and they permit us to explain the signs
and quantitative differences of ΔH
0 and ΔS
0 on the basis of the different cavity sizes and the movement of the guest inside the HPCD cavity. Results also reveal a more
favorable complexation when 2MN approaches on its polar side. 相似文献
5.
Cristiano Andrade-Dias Brian J. Goodfellow Luís Cunha-Silva José J. C. Teixeira-Dias 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):151-156
The association in aqueous solutions of small amphiphilic molecules [2-phenoxyethanol, PhE1, and some α-n-alkyl-ω-hydroxyoligo(oxiethylenes], C4E1, C4E2 and C6E2) with β-cyclodextrin (βCD), heptakis(2,6-di-O-methyl)-β-cyclodextrin (DIMEB) and heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin (TRIMEB) was investigated by 1H NMR spectroscopy. The upfield shifts observed for the H3 and H5 NMR signals due to anisotropic shielding confirm that the
host–guest associations are of inclusion type. The stoichiometries and the apparent inclusion constants, K
app, were determined by 1H NMR spectroscopy using the H5 and H3 signals. The relative differences in the K
app values for βCD inclusion complexes seem to reflect the hydrophobic/hydrophilic balance of the guests. The K
app values for the PhE1 inclusion complexes can be related to the degree of methylation and hydrophobicity variation within the considered hosts.
In addition, a comparative study between βCD and TRIMEB inclusion complexes using 2D ROESY (Rotating-frame Overhauser Enhancement
SpectroscopY) NMR spectra provides structural features for these complexes which are inaccessible by other experimental methods. 相似文献
6.
A. V. Pestov P. A. Slepukhin L. S. Molochnikov M. A. Ezhikova M. I. Kodess Yu. G. Yatluk 《Russian Journal of Inorganic Chemistry》2010,55(2):201-208
N-(3-Hydroxypropyl)-β-alanine was synthesized by the reacti on of 3-aminopropanol with acrylic acid. From this ligand and basic
copper carbonate, bis(N-(3-hydroxypropyl)-β-alaninato)dicopper(II) [Cu2 (C6H11NO3)2] was obtained. The structures of the chelating agent and the copper complex were studied by X-ray diffraction. The Cu(II)
coordination polyhedron is a distorted square pyramid. Each ligand forms six-membered β-alaninate and propanolamine chelate
rings. The propoxy group functions as a bridge. In the crystal structure, the molecules form intermolecular coordination bonds
C=O→Cu, which are perpendicular to the layers. The EPR signal typical of dimeric copper complexes is not observed due to low
occupancy of the excited paramagnetic triplet state. The weak paramagnetic signal from monomeric copper complex allowed recording
of the 1H NMR spectrum of [Cu2 (Pro-ala) 2] with characteristic line broadening and contact shift. It follows from the obtained data that on dissolution, the complex
dissociates by 40% to give monomeric copper complexes. 相似文献
7.
Structural analysis of three novel trisaccharides isolated from the fermented beverage of plant extracts 总被引:1,自引:0,他引:1
Hideki Okada Eri Fukushi Akira Yamamori Naoki Kawazoe Shuichi Onodera Jun Kawabata Norio Shiomi 《Chemistry Central journal》2009,3(1):8-8
Background
A fermented beverage of plant extracts was prepared from about fifty kinds of vegetables and fruits. Natural fermentation was carried out mainly by lactic acid bacteria (Leuconostoc spp.) and yeast (Zygosaccharomyces spp. and Pichia spp.). We have previously examined the preparation of novel four trisaccharides from the beverage: O-β-D-fructopyranosyl-(2->6)-O-β-D-glucopyranosyl-(1->3)-D-glucopyranose, O-β-D-fructopyranosyl-(2->6)-O-[β-D-glucopyranosyl-(1->3)]-D-glucopyranose, O-β-D-glucopyranosyl-(1->1)-O-β-D-fructofuranosyl-(2<->1)-α-D-glucopyranoside and O-β-D-galactopyranosyl-(1->1)-O-β-D-fructofuranosyl-(2<->1)- α-D-glucopyranoside. 相似文献8.
Yoshimi Sueishi Naoya Inazumi Tatsuhiro Ide Tadashi Hanaya 《Journal of inclusion phenomena and macrocyclic chemistry》2006,54(3-4):201-208
The inclusion complexation of 6-O-α-D-glucosyl-β-cyclodextrin (G-β-CD), in which the glucosyl side chain is introduced to β-CD, with various kinds of phenols was studied spectrophotometrically at high pressures. The characteristic effects of substituent and pressure were found for the inclusion complexation of G-β-CD. The association constants K for the G-β-CD inclusion complexation increased with an increase in the bulkiness of the 4-substituent groups in phenols. As the external pressure increases, the inclusion constants for the G-β-CD complexation increased and the reaction volumes were estimated to be −3.8 to −19.4 cm3 mol−1 from their pressure dependences. From analysis of the effect of pressure on the inclusion complexation with G-β-CD, the number of water molecules included in the G-β-CD cavity in water was estimated. The number of water molecules repelled from the CD cavity plays an important role in the change in volume upon inclusion. In addition, the structures of the inclusion complexes of G-β-CD with phenols have been established by 1D and 2D NMR measurements. Based on the results, we suggested that the ability of the G-β-CD inclusion complexation is enhanced by the interaction between guest molecules and the glucosyl side chain of G-β-CD. 相似文献
9.
N. S. Arutyunyan L. A. Akopyan G. M. Snkhchyan O. A. Papoyan G. A. Panosyan G. A. Gevorgyan 《Chemistry of Heterocyclic Compounds》2006,42(4):440-445
Ethyl α-cyano-β-(p-fluorophenyl)-β-(2-furyl)propionate was obtained by the condensation of ethyl α-cyano-β-(2-furyl)acrylate
with p-fluorophenylmagnesium bromide. Its deethoxycarbonylation led to β-(p-fluorophenyl)-β-(2-furyl)propionitrile. Reduction
of the nitrile with lithium aluminum hydride gave γ-(p-fluorophenyl)-γ-(2-furyl)propylamine. Some transformations of the latter
were studied.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 503–509, April, 2006. 相似文献
10.
V. I. Grishkovets A. A. Loloiko A. S. Shashkov V. Ya. Chirva 《Chemistry of Natural Compounds》1990,26(6):663-666
We have isolated from Crimean ivy berries in addition previously known triterpene glycosides — 3-O-α-L-arabinopyranosyl-28-O-[O-α-L-rhamnopyranosyl-(1
→ 4)-O-β-D-glycopyranosyl-(1 → 6)-β-D-glucopyranosyl]hederagenin, 3-O-[O-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosyl]-28-O-[O-α-L-rhamnopyranosyl-(1
→ 4)-O-β-D-glucopyranosyl-(1 → 6)-β-D-glycopyranosyl]hederagenin, the new triterpene glycosides hederoside H2-3-O-[O-β-D-glycopyranosyl-(1 → 2)-β-D-glycopyranosyl-(1 → 2)-β-D-glucopyranosyl]-28-O-[O-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl]oleanolic
acid- and hederoside I-3-O-[O-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosyl]-28-O-[O-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl]hederagenin.
Details of their13C NMR spectra are given.
M. V. Frunze Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 779–783, November–December,
1990. 相似文献
11.
A. N. Kel'ginbaev M. B. Gorovits T. T. Gorovits N. K. Abubakirov 《Chemistry of Natural Compounds》1976,12(4):422-427
From a methanolic extract of the skins of the bulbs ofAllium giganteum Rgl, a new steroid glycoside has been isolated — aginoside, which is (25R)-5α-spirostan-2α, 3β, 6β-triol 3-0-{[0-β-D-xylopyranosyl-(1→3)-]-[0-β-D-glucopyranosyl-(1→2)]-0-β-D-glucopyranosyl-(1→4)-0-β-D-galactopyranoside}. 相似文献
12.
Mono(6-deoxy-dimethylpyridinium)-β-cyclodextrins have been synthesized in reaction of mono (p-toluenesulfonyl) derivative
of β cyclodextrin with the appropriate lutidine under microwave irradiation and conventional conditions. The results indicate
that the mechanism consists of inclusion complex formation. 相似文献
13.
Binary Systems of Nifedipine And Various Cyclodextrins in The Solid State. Thermal,FTIR, XRD studies
Brown M. E. Glass B. D. Worthington M. S. 《Journal of Thermal Analysis and Calorimetry》2002,68(2):631-646
Nifedipine complexes with β-cyclodextrin (β-CD), γ-cyclodextrin (γ-CD), 2-hydroxypropyl-β-cyclodextrin (2HP-β-CD), randomly
methylated-β-cyclodextrin (RM-β-CD) and heptakis(2,6-O-dimethyl)-β-cyclodextrin (DM-β-CD) have been prepared by both kneading and heating methods and their behaviour studied by
differential scanning calorimetry (DSC), diffuse reflectance mid-infrared spectroscopy (FTIR) and X-ray diffractometry (XRD).
DSC revealed the nifedipine melting endotherm with onset at approximately 171°C for the kneaded mixtures with β-CD, γ-CD and
2HP-β-CD, thus confirming the presence of nifedipine in the crystalline state, while some decrease in crystallinity was observed
in the DM-β-CD kneaded mixture. With RM-β-CD, however, broadening and shifting of the nifedipine endotherm and reduction in
its intensity suggested that the kneading could have produced an amorphous inclusion complex. These differing extents of interaction
of nifedipine with the cyclodextrins were confirmed by FTIR and XRD studies.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
14.
D. Q. Xiao B. Q. Che R. N. Fu J. L. Gu Y. X. Wen Y. Ling H. B. Zhang 《Chromatographia》1997,44(7-8):393-398
Summary Heptakis(2,6-di-O-benzyl)-β-CD(I), heptakis(2,6-di-O-benzyl-3-O-pentyl)-β-CD(II), heptakis(2,6-di-O-benzyl-3-O-methyl)-β-CD(III)
and heptakis(2,6-di-O-benzyl-3-O-acetyl)-β-CD(IV) derivatives were synthesized and identified. Their thermal stabilities were
tested using PyGC. These CD derivatives are stable up to 300°C and suitable for use as gas chromatographic stationary phases.
The fused silica capillary columns coated with heptakis(2,6-di-O-benzyl-3-O-methyl)-β-CD and heptakis(2,6-di-O-benzyl-3-O-pentyl)-β-CD
showed excellent chromatographic properties in separating positional isomers. 相似文献
15.
Ciarán F. Potter Noel R. Russell Mary McNamara 《Journal of inclusion phenomena and macrocyclic chemistry》2006,56(3-4):395-403
The derivatives 6-Deoxy-6-[1-(2-amino)ethylamino]-β-Cyclodextrin (CDEn), 6-Deoxy-6-[1-(3-amino)propylamino]-β-Cyclodextrin
(CDPn) and 6-Deoxy-6-[1-(4-amino)butylamino]-β-Cyclodextrin (CDBn) were assessed with a view to demonstrating that increasing
the chain length of the diaminoalkane moiety can affect the chiral selectivity of the metallo-complexes of these materials.
It was shown that IR and Raman spectroscopies can be used to characterise these compounds. The results obtained from the electronic
absorption spectra suggested the formation of CuCDAm binary complexes and that the derivatives CDEn and CDPn act as bidentate
ligands while CDBn acts as a monodentate ligand due to its longer alkane chain. This study also showed that in the ternary
complexes with DOPA there is further coordination of the metal ion to the amino nitrogen atom and the hydroxyl oxygen atom
of the drug. On the basis of the results of the circular dichroic spectroscopic studies it was suggested that CuCDEn is the
better enantioselective material for DOPA and it acts in a multi-site recognition manner, utilising the inclusion properties
of the CD cavity in cooperation with the coordination properties of the metal ion. 相似文献
16.
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
17.
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
18.
Chemical investigation of the aerial part of Peganum nigellastrum furnished a new flavone glycoside, and the structure was established by NMR, MS, and DEPT, HSQC, and HMBC as diosmetin 7-O-β-Dglucopyranosyl(1→2)-β-D-glucopyranosyl(1→2)-[α-L-rhamnopyranosyl(1→6)]-β-D-glucopyranoside. 相似文献
19.
The self-assembly behavior of mono(6-phenolic-6-deoxy)-β-cyclodextrin (1) both in solution and the solid state is comparatively studied by X-ray crystallography and 1H NMR spectroscopy. The results obtained show that the phenolic groups in the crystal 1 can successively penetrate into the
adjacent β-cyclodextrin cavities from the secondary side to form head-to-tail linear polymeric supramolecule with a 2-fold
screw axis. The self-assembly behavior also can be determined in D2O solution, giving a self-association constant of 240 mol−1·L. Using the present and previous structures reported for the relevant β-cyclodextrin derivatives, i.e., mono(6-anilino-6-deoxy)-β-cyclodextrin
(2), mono(6-phenylselenyl-6-deoxy)-β-cyclodextrin (3), and mono(6-phenylthio-6-deoxy)-β-cyclodextrin (4), we further reveal the factors governing the formations of supramolecular assemblies. 相似文献
20.
2-Aminoethyl glycoside of the hexasaccharide chain of ganglioside Fuc-GM1 was synthesized by a [3+3] synthetic scheme. At the key step of the synthetic route, glycosylation of the only hydroxyl group
at C(4) of the galactose residue in an α-(N-acetylneuraminyl)-(2→3)-β-D-galactopyranosyl-(1→4)-β-D-glucopyranoside derivative
with a peracetylated thioglycoside of α-L-fucopyranosyl-(1→2)-β-D-galactopyranosyl-(1→3)-2-trichloroacetamido-2-deoxy-β-D-galactopyranose
gave a protected hexasaccharide in high yield. Subsequent removal of the protecting groups gave the target 2-aminoethyl glycoside
of the oligosaccharide chain of gan-glioside Fuc-GM1.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 148–153, January, 2006. 相似文献