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Kawasaki, Koji; Hasegawa, Hideki

doi:10.1023/a:1014429907212

Cited by 17 publications

(7 citation statements)

References 11 publications

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“…Meanwhile, Kano and co-workers reported the inclusion complexes between anionic N-acetylated R-amino acids (AcTrp -, AcPhe -, AcLeu -, and AcVal -) and protonated heptakis(6amino-6-deoxy)-β-CD (per-NH 3 + -β-CD) by a cooperative effect of inclusion and Coulombic interactions. 9 In addition, they also determined the thermodynamic parameters for the complexation of multiply charged CD cations and anions with oppositely charged guest molecules. 10 More recently, we reported that the cationic aminated β-CDs could significantly alter the molecular binding ability and selectivity of the parent β-CD toward the anionic steroids through cooperative electrostatic interactions, van der Waals, and hydrophobic interactions between hosts and guests.…”

Section: Introductionmentioning

confidence: 99%

“…This revealed the counterbalance between electrostatic and conventional intracavity interactions including van der Waals, hydrogen bonding, and hydrophobic interactions. Meanwhile, Kano and co-workers reported the inclusion complexes between anionic N-acetylated α-amino acids (AcTrp - , AcPhe - , AcLeu - , and AcVal - ) and protonated heptakis(6-amino-6-deoxy)-β-CD (per-NH 3 + -β-CD) by a cooperative effect of inclusion and Coulombic interactions . In addition, they also determined the thermodynamic parameters for the complexation of multiply charged CD cations and anions with oppositely charged guest molecules .…”

Section: Introductionmentioning

confidence: 99%

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Effect of β-Cyclodextrin Charge Type on the Molecular Recognition Thermodynamics of Reactions with (Ferrocenylmethyl)dimethylaminium Derivatives

et al. 2008

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Complex stability constants (KS), standard molar enthalpic changes (DeltaH degrees ), and entropic changes (TDeltaS degrees ) for the inclusion complexations of native beta-cyclodextrin (1) and two oppositely charged beta-cyclodextrins, i.e., mono(6-amino-6-deoxy)- beta-cyclodextrin (2) and mono[6-O-6-(4-carboxylphenyl)]- beta-cyclodextrin (3), with two (ferrocenylmethyl)dimethylaminium derivatives, i.e., FC4+Br(-) and FC8+Br(-), were determined at 25 degrees C in aqueous phosphate buffer solution (pH 7.20) by means of isothermal titration microcalorimetry (ITC). Cyclic voltammetry studies showed that the ferrocene groups of the guests were included in the beta-cyclodextrin cavity to form host-guest complexes. As compared with neutral beta-cyclodextrin, the positively charged host 2 showed decreased binding toward (ferrocenylmethyl)dimethylaminium guests. This was attributed to electrostatic repulsion, while the negatively charged host 3 displayed increased binding due to electrostatic attractions. Thermodynamically, the ionization of host CDs affects both enthalpic and entropic changes of host-guest complexations presumably by changing the hydrophobicity and the desolvation effect of hosts upon inclusion complexation. Moreover, the solvent effect was also discussed from the viewpoint of thermodynamics.

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Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Effect of β-Cyclodextrin Charge Type on the Molecular Recognition Thermodynamics of Reactions with (Ferrocenylmethyl)dimethylaminium Derivatives

et al. 2008

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“…This internal cavity is capable of accommodating a wide range of guest molecules, ranging from polar compounds such as alcohols, acids, amines, and small inorganic anions to nonpolar aliphatic and aromatic hydrocarbons . The inside cavity of appropriate dimension is conducive to binding to various guest molecules to form inclusion complexes in aqueous solution which find potential applications in pharmaceutical science, catalysis, and separation technology, − and in affinity chromatography , as chiral discriminators against optically active molecules. Owing to multifunctional characteristics and bioadaptability, α-, β-, and γ-CDs have been explored in biochemistry and drug research.…”

Section: Introductionmentioning

confidence: 99%

Molecular Electrostatic Potentials and Hydrogen Bonding in α-, β-, and γ-Cyclodextrins

2006

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Cyclodextrins (CDs) are cyclic oligomers of glucose having the toroid of sugars elaborating a central cavity of varying size depending on the number of glucoses. The central hydrophobic cavity of CD shows a binding affinity toward different guest molecules, which include small substituted benzenes to long chain surfactant molecules leading to a variety of inclusion complexes when the size and shape complementarity of host and guest are compatible. Further, interaction of guest molecules with the outer surface of alpha-CD has also been observed. Primarily it is the electrostatic interactions that essentially constitute a driving force for the formation of inclusion complexes. To gain insights for these interactions, the electronic structure and the molecular electrostatic potentials in alpha-, beta-, and gamma-CDs are derived using the hybrid density functional theory employing the three-parameter exchange correlation functional due to Becke, Lee, Yang, and Parr (B3LYP). The present work demonstrates how the topography of the molecular electrostatic potential (MESP) provides a measure of the cavity dimensions and understanding of the hydrogen-bonded interactions involving primary and secondary hydroxyl groups. In alpha-CD, hydrogen-bonded interactions between primary -OH groups engender a "cone-like" structure, while in beta- or gamma-CD the interactions from the primary -OH with ether oxygen in glucose ring facilitates a "barrel-like" structure. Further, the strength of hydrogen-bonded interactions of primary -OH groups follows the rank order alpha-CD > beta-CD > gamma-CD, while the secondary hydrogen-bonded interactions exhibit a reverse trend. Thus weak hydrogen-bonded interactions prevalent in gamma-CD manifest in shallow MESP minima near hydroxyl oxygens compared to those in alpha- or beta-CD. Furthermore, electrostatic potential topography reveals that the guest molecule tends to penetrate inside the cavity forming the inclusion complex in beta- or gamma-CD.

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“…The general findings of these studies are that anionic CDs are more effective chiral NMR solvating agents for cationic substrates than neutral native CDs. Similarly cationic CDs containing amine [39–40], xylylenediamine [41], and trialkylammonium groups [42–44] are found to be more effective for anionic substrates than the neutral native CDs.…”

Section: Introductionmentioning

confidence: 99%

Phosphated cyclodextrins as water-soluble chiral NMR solvating agents for cationic compounds

Puentes¹,

Wenzel²

2017

Beilstein J. Org. Chem.

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The utility of phosphated α-, β- and γ-cyclodextrins as water-soluble chiral NMR solvating agents for cationic substrates is described. Two sets of phosphated cyclodextrins, one with degrees of substitution in the 2–6 range, the other with degrees of substitution in the 6–10 range, are examined. Results with 33 water-soluble cationic substrates are reported. We also explored the possibility that the addition of paramagnetic lanthanide ions such as praseodymium(III) and ytterbium(III) further enhances the enantiomeric differentiation in the NMR spectra. The chiral differentiation with the phosphated cyclodextrins is compared to prior results obtained with anionic carboxymethylated cyclodextrins. There are a number of examples where a larger differentiation is observed with the phosphated cyclodextrins.

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Untitled

Cited by 17 publications

References 11 publications

Effect of β-Cyclodextrin Charge Type on the Molecular Recognition Thermodynamics of Reactions with (Ferrocenylmethyl)dimethylaminium Derivatives

Effect of β-Cyclodextrin Charge Type on the Molecular Recognition Thermodynamics of Reactions with (Ferrocenylmethyl)dimethylaminium Derivatives

Molecular Electrostatic Potentials and Hydrogen Bonding in α-, β-, and γ-Cyclodextrins

Phosphated cyclodextrins as water-soluble chiral NMR solvating agents for cationic compounds

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