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Chem. Commun., 2010, 46, 4514-4516
DOI: 10.1039/B924936B , Communication
M. Victoria Gomez, Hein H. J. Verputten, Angel Díaz-Ortíz, Andres Moreno, Antonio de la Hoz and Aldrik H. Velders
We report the use of a nanolitre nuclear magnetic resonance (NMR) spectroscopy microfluidic chip hyphenated to a continuous-flow microlitre-microwave irradiation set-up, for on-line monitoring and rapid optimization of reaction conditions.
Rational synthesis, enrichment, and 13C NMR spectra of endohedral C60 and C70 encapsulating a helium atom
Endohedral fullerenes encapsulating a helium atom, i.e., He@C60 and He@C70, at occupation levels of 30% were prepared by rational chemical synthesis. The existence of weak interactions between the inner helium and the outer fullerene cages was demonstrated by experimental and computational investigations.
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Chem. Commun., 2010, 46, 4982-4984
DOI: 10.1039/C0CC01007C
Application of a technique developed for in situ solid-state 13C NMR studies of crystallization processes reveals direct evidence that crystallization of glycine from a methanol/water solution involves the initial transient formation of the β polymorph, which then undergoes a solution-mediated polymorphic transformation to yield the more stable α polymorph.
***Chem. Commun., 2010, 46, 5879-5881
DOI: 10.1039/C0CC01271H
Residual dipolar couplings (RDCs) obtained in a stretched polydimethylsiloxanegel are applied to determine the 7-membered ring conformation in a 2-phenyl-3-benzazepine derivative, and to simultaneously assign all methyleneproton pairs using only 1DCH RDCs and DFT molecular modelling data.
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Chem. Commun., 2010, 46, 6714-6716
DOI: 10.1039/C0CC00829J
Two-dimensional homo- and heteronuclear solid-state MAS NMR experiments on 13C/15N-proline labeled Argiope aurantia dragline silk provide evidence for an elastin-like β-turn structure for the repetitive Gly-Pro-Gly-X-X motif prevalent in major ampullate spidroin 2 (MaSp2).
***Chem. Commun., 2010, 46, 6774-6776
DOI: 10.1039/C0CC01902J
We show that ultra-wideline solid-state 14N NMR can be used as a quantitative probe of molecular dynamics. Jump rates for the molecular flipping mechanism in crystalline urea are determined at various temperatures and are shown to be in good agreement with other NMR techniques.
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Chem. Commun., 2010, 46, 7533-7535
DOI: 10.1039/C0CC01846E
We report the first example of peptide–protein heteronuclear two-dimensional (2D) saturation transfer difference nuclear magnetic resonance (STD NMR). This method, resulting in dramatically reduced overlap, was applied to the interaction of the integrin αvβ6 with a known peptide ligand and highlights novel contact points between the substrate and target protein.
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Chem. Commun., 2010, 46, 8192-8194
DOI: 10.1039/C0CC01953D
The polarisation of abundant protons, rather than dilute nuclei with low gyromagnetic ratios, can be enhanced in less than 10 min using dissolution DNP and converted into a long-lived state delocalised over an ensemble of three coupled protons. The process is more straightforward than the hyperpolarisation of heteronuclei followed by magnetisation transfer to protons.
***Chem. Commun., 2010, 46, 8273-8275
DOI: 10.1039/C0CC02730H
Perdeuterated poly(acrylonitrile) is introduced as a practically proton-free alignment medium for the measurement of anisotropic NMR parameters; its use in conventional glass tubes and in a Kalrez® 8002 UP-based stretching device with resulting spectra of astonishing quality are demonstrated.
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