Complexes of natural carbohydrates with metal cations

Alekseev, Yurii E; Гарновский, А. Д.; Zhdanov, Yu. A.

doi:10.1070/rc1998v067n08abeh000343

Cited by 75 publications

(34 citation statements)

References 413 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Owing to its high affinity325 toward carboxyl groups of GalA residues, copper ions extensively form complexes326 with pectins. In contrast to the purification system based on protein-pectin327 interactions, negatively pectins in this system, may serve as polymeric and328 polydentate ligands(Alekseev, Garnovskii, & Zhdanov, 1998). In addition, 329 copper-pectin complexes may form via forming chelate bonds (Kohn, Heinrichová, & 330 Malovíková, 1983) rather than electrostatic bonds involved in the formation of 331 copper ions and pectins were previously studied.…”

mentioning

confidence: 99%

Purifying sugar beet pectins from non-pectic components by means of metal precipitation

et al. 2015

View full text Add to dashboard Cite

mentioning

confidence: 99%

Purifying sugar beet pectins from non-pectic components by means of metal precipitation

et al. 2015

View full text Add to dashboard Cite

“…Note that information on the incorporation of transition metal complexes in the CD cavity is available. 28 The spin exchange mechanism considered above also shows that the high environment polarity of the NO group (see Table 1) is due to the formation of hydrogen bonds with water molecules inside the cavity rather than local ization of this group on the surface of γ CD. X Ray analy sis data revealed the presence of three water molecules at three out of eight binding sites inside the γ CD cavity.…”

Section: Resultsmentioning

confidence: 95%

Inclusion complexes of spin-labeled indoles with cyclodextrins in aqueous solutions

et al. 2005

View full text Add to dashboard Cite

Guest host complexes of β and γ cyclodextrins (CDs) with two spin labeled indole de rivatives having the same molecular weights but different structures were studied by EPR spectroscopy in aqueous solutions and semiempirical quantum chemical calculations of these systems were carried out. In the presence of CD the polarity of the NO group environment decreases and the rotational correlation time (τ) of guest molecules increases. Both indole derivatives form 1 : 1 complexes with γ CD, the binding constants of the complexes being different more than twice. Simulation of EPR spectra made it possible to determine the indole ring orientation relative to the plane of the host molecule (at angles in the range 30-60°) and the rotational diffusion coefficients of the complexes, which corresponded to the hydro dynamic volume of one γ CD molecule. In contrast to the complexes with γ CD the rotational correlation times, τ, of the complexes with β CD correspond to a hydrodynamic volume which much exceeds the volume of a single β CD molecule. The complexes with β CD are also characterized by more hydrophobic environment for guest molecules and absence of spin exchange with Ni 2+ ions in the aqueous solution. There results are consistent with a dimeric structure of β CD in the complex and with the orientation of the long axis of the guest molecule along the dimer axis. The energies and geometric parameters were calculated for all complexes by the PM3 method with a conventional set of parameters. The optimized energeti cally stable structures of the 1 : 1 complexes with γ CD and of the 1 : 2 complexes with β CD are consistent with experimental data.

show abstract

“…[1] Nonetheless the corresponding compounds containing organometallic moieties are still very rare. [2] This is a surprizing fact, since in the area of enantioselective catalysis using organometallic complexes a great deal of effort has been put into the syntheses of a plethora of chiral ligands; however, by far most of them are not derived from saccharides although just these carbohydrates seem to be very suitable starting materials because of their diverse stereo information.…”

Section: Introductionmentioning

confidence: 99%

Organometallic Supramolecular Chemistry with Monosaccharides: Triethylammoniumμ-Chloro-bis{chloro(η5-cyclopentadienyl)(methyl 4,6-O-benzylidene-β-D-glucopyranosidato-1κO2,1:2κO3)zirconate}

Jessen¹,

Haupt²,

Heck³

2001

Chem. Eur. J.

View full text Add to dashboard Cite

The reaction of [CpZrCl 3 (thf) 2 ] with methyl 4,6-Obenzylidene-b-d-glucopyranoside (bMeBGH 2 , 1) in the presence of Et 3 N results in the formation of the zirconate complex [Et 3 NH][(CpZrCl) 2(2). X-ray structure analyses were performed from the ligand precursor b-MeBGH 2 1 as well as from 2. Compound 1 crystallizes in the monoclinic chiral space group P2 1 . The molecules show a flat arrangement including the benzylidene protecting group, and are packed in columns. The columns are held together in pairs by the formation of hydrogen bonds between the hydroxy functions in positions 2 and 3. Compound 2 crystallizes in the orthorhombic space group P2 1 2 1 2 1 . The b-MeBG ligands are chelating the Zr atoms through the oxygen atoms in positions 2 and 3 of the glucopyranosidato ligand revealing a 1-zircona-2,5-dioxolane moiety each; the oxygen atom in position 3 is linked to both of the Zr atoms. Additionally one chloro ligand is bridging the two Zr centers. Two terminally bound chloro ligands stick out from the two Zr atoms into a chiral U-shaped cavity constructed by the two b-MeBG ligands. The cavity incorporates the tertiary ammonium cation [Et 3 NH] , which is bound to one of the terminal chloro ligands through a hydrogen bond. The inclusion of the [Et 3 NH] cation in the U-shaped cavity, even in solution, is demonstrated by NMR spectroscopic data.

show abstract

Complexes of natural carbohydrates with metal cations

Cited by 75 publications

References 413 publications

Purifying sugar beet pectins from non-pectic components by means of metal precipitation

Purifying sugar beet pectins from non-pectic components by means of metal precipitation

Inclusion complexes of spin-labeled indoles with cyclodextrins in aqueous solutions

Organometallic Supramolecular Chemistry with Monosaccharides: Triethylammoniumμ-Chloro-bis{chloro(η5-cyclopentadienyl)(methyl 4,6-O-benzylidene-β-D-glucopyranosidato-1κO2,1:2κO3)zirconate}

Contact Info

Product

Resources

About