@inbook {doi:10.1002/9780470034590.emrstm1477,
	title = {Molecular Hydrogens Dissolved in Liquid Crystals},
	booktitle = {eMagRes},
	year = {2016},
	pages = {901-912},
	publisher = {American Cancer Society},
	organization = {American Cancer Society},
	abstract = {Abstract The NMR spectra of molecular hydrogen isotopologs dissolved and orientationally ordered in nematic liquid-crystal solvents provide a wealth of information. Because they are quantum rotors, the various isotopologs H 2 , D 2 , T 2 , HD, HT, and DT have different order parameters, with larger internuclear distance having smaller order parameter. The signs and magnitudes of the order parameters are liquid-crystal dependent, this being a direct result of the dominant anisotropic intermolecular interaction being that between the solute quadrupole moment and the mean liquid-crystal electric-field gradient (EFG) felt by the solute. Thus, the mixing of different liquid crystals can produce a solvent where molecular hydrogen feels a zero EFG, called a magic mixture. The remaining, dominant anisotropic interaction (for solutes larger than hydrogen) in these magic mixtures involves short-range anisotropic forces that depend on solute size and shape. Studies involving the very symmetrical methane H, D, and T isotopologs point out the important effect on dipolar couplings of molecular vibrations and interactions between molecular vibration and reorientation, effects which make it impossible to utilize fully the high accuracy with which dipolar couplings in general can be measured.},
	keywords = {ANISOTROPIC, electric field gradient, HYDROGEN, liquid crystal, METHANE, NMR, order parameter, ordered liquids, ORIENTATION, VIBRATIONS},
	isbn = {9780470034590},
	doi = {10.1002/9780470034590.emrstm1477},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/9780470034590.emrstm1477},
	author = {Burnell, E. Elliott and de Lange, Cornelis A.}
}
@article {2680,
	title = {N-Heterocyclic Carbene Rhodium Complexes and Their Reactions with H-2 and with CO},
	journal = {European Journal of Inorganic Chemistry},
	number = {13},
	year = {2009},
	note = {ISI Document Delivery No.: 447KWTimes Cited: 5Cited Reference Count: 53Yu, Xiao-Yan Sun, Hongsui Patrick, Brian O. James, Brian R.},
	month = {May},
	pages = {1752-1758},
	type = {Article},
	abstract = {The NHC-Rh-I complexes [RhCl(COE)(NHC)](2) 1 and 2 [COE = cyclooctene, NHC in 1 = N,N-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (IPr) and, in 2, N,N-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene (IMes)] react with H-2 in hexane to give the dimeric, mono-carbene dihydrido species [Rh(H)(2)Cl(NHC)](2) (NHC = IPr (3), IMes (4)). In the presence of further NHC, the bis-carbene dihydrido species Rh(H)(2)Cl(NHC)(2) are formed; a crystal structure of the IPr complex 5 is analogous to that of the known IMes analogue. The dihydride-mixed-carbene species Rh(H)(2)Cl(IPr)(IMes) (5a) was also observed but not isolated. A benzene solution of 5 under D-2 slowly generates the corresponding dideuteride. Reactions of the mono-carbenes (1/3, or 2/4) with CO in hexane afford the respective dicarbonyl complexes RhCl(CO)(2)(NHC) [NHC = IPr (6), IMes (7)], while CO reactions with the bis-carbene dihydrides give, respectively, the mono-carbonyl complex RhCl(CO)(IPr)(2) (8) and the known IMes analogue. All the complexes are characterized by elemental analysis, H-1 and C-13{H-1} NMR and IR spectroscopies and, in the case of 5, by X-ray crystallography. The catalytic activities of 5 and the previously reported Rh(H)(2)Cl(IMes)(2) for hydrogenation of COE and 1-octene (and isomerization of the latter) are shown to be poor. ((c) Wiley-VCH Verlag GmbH \& Co. KGaA, 69451 Weinheim, Germany, 2009)},
	keywords = {14-ELECTRON, Carbene ligands, carbonyl ligands, CATALYTIC-ACTIVITY, COORDINATION CHEMISTRY, H ACTIVATION, Hydrides, HYDROFORMYLATION, HYDROGENATION, iridium complexes, LIGANDS, NHC COMPLEX, NMR, RH(III), rhodium},
	isbn = {1434-1948},
	url = {<Go to ISI>://000266191000009},
	author = {Yu, X. Y. and Sun, H. S. and Patrick, B. O. and James, Brian R.}
}
@article {2399,
	title = {Orientational order of near D-3h solutes in nematic liquid crystals},
	journal = {Journal of Chemical Physics},
	volume = {130},
	number = {15},
	year = {2009},
	note = {ISI Document Delivery No.: 437KLTimes Cited: 2Cited Reference Count: 49Danilovic, Zorana Burnell, E. Elliott},
	month = {Apr},
	pages = {11},
	type = {Article},
	abstract = {Solutes that are similar in size, have a shape that is close to D-3h symmetry but contain dissimilar substituent groups (methyl versus chloro, contributing different electrostatic interactions to the anisotropic intermolecular potential), are used to delineate the short- and long-range anisotropic intermolecular interactions that lead to solute orientational order in nematic liquid crystals. The short-range interactions should be similar for all solutes and for D-3h symmetry should yield a single independent order parameter, whereas the long-range interactions are expected to differ with solute. Short-range size and shape mechanisms account for solute orientational order measured in magic mixtures (e.g., 55 wt \% ZLI-1132/N-p-ethoxybenzylidene-p({\textquoteright})-n-butylaniline), whereas additional mechanisms are required in other nematic liquid-crystal solvents. The results obtained for long-range interactions cannot be rationalized in detail using simple mean-field models that incorporate solute dipoles, quadrupoles, or polarizabilities. The results suggest that details of the solute electrostatics may need to be incorporated into the description of the anisotropic intermolecular potential.},
	keywords = {AB-INITIO, ELECTRIC-FIELD GRADIENT, electrostatic, interactions, liquid crystals, LIQUID MIXTURES, liquid structure, MEAN TORQUE, molecular orientation, MOLECULAR-HYDROGEN, MONTE-CARLO SIMULATIONS, nematic, NMR, polarisability, POTENTIALS, SHAPE, SOLVENTS},
	isbn = {0021-9606},
	url = {<Go to ISI>://000265486300032},
	author = {Danilovic, Z. and Burnell, E. E.}
}
@article {2141,
	title = {The affinity of Ets-1 for DNA is modulated by phosphorylation through transient interactions of an unstructured region},
	journal = {Journal of Molecular Biology},
	volume = {382},
	number = {4},
	year = {2008},
	note = {ISI Document Delivery No.: 359YPTimes Cited: 3Cited Reference Count: 42Lee, Gregory M. Pufall, Miles A. Meeker, Charles A. Kang, Hyun-Seo Graves, Barbara J. McIntosh, Lawrence P.},
	month = {Oct},
	pages = {1014-1030},
	type = {Article},
	abstract = {Binding of the transcription factor Ets-1 to DNA is allosterically regulated by a serine-rich region (SRR) that modulates the dynamic character of the adjacent structured DNA-binding ETS domain and its flanking autoinhibitory elements. Multi-site phosphorylation of the flexible SRR in response to Ca2+ signaling mediates variable regulation of Ets-1 DNA-binding affinity. In this study, we further investigated the mechanism of this regulation. First, thermal and urea denaturation experiments demonstrated that phosphorylation of the predominantly unstructured SRR imparts enhanced thermodynamic stability on the well-folded ETS domain and its inhibitory module. We next identified a minimal fragment (residues 279-440) that exhibits both enhanced autoinhibition of Ets-1 DNA-binding and allosteric reinforcement by phosphorylation. To test for intramolecular interactions between the SRR and the rest of the fragment that were not detectable by H-1-H-1 NOE measurements, paramagnetic relaxation enhancements were performed using Cu2+ bound to the N-terminal ATCUN motif. Increased relaxation detected for specific amide and methyl groups revealed a preferential interaction surface for the flexible SRR extending from the inhibitory module to the DNA-binding interface. Phosphorylation enhanced the localization of the SRR to this surface. We therefore hypothesize that the positioning of the SRR at the DNA-binding interface and its role in shifting Ets-1 to an inhibited conformation are linked. In particular, transient interactions dampen the conformational flexibility of the ETS domain and inhibitory module required for high-affinity binding, as well as possibly occlude the DNA interaction site. Surprisingly, the phosphorylation-dependent effects were relatively insensitive to changes in ionic strength, suggesting that electrostatic forces are not the dominant mechanism for mediating these interactions. The results of this study highlight the role of flexibility and transient binding in the variable regulation of Ets-1 activity. (C) 2008 Elsevier Ltd. All rights reserved.},
	keywords = {allosteric regulation, ATCUN MOTIF, AUTOINHIBITION, BINDING, CHEMICAL-SHIFTS, DISORDERED PROTEIN, DOMAIN, DYNAMICS, GROUP HYDROGEN-EXCHANGE, NMR, paramagnetic relaxation, PARAMAGNETIC RELAXATION ENHANCEMENT, protein dynamics, SPECTROSCOPY, transcription},
	isbn = {0022-2836},
	url = {<Go to ISI>://000260024500017},
	author = {Lee, G. M. and Pufall, M. A. and Meeker, C. A. and Kang, H. S. and Graves, B. J. and McIntosh, L. P.}
}
@article {2120,
	title = {Identification and structural characterization of a CBP/p300-binding domain from the ETS family transcription factor GABP alpha},
	journal = {Journal of Molecular Biology},
	volume = {377},
	number = {3},
	year = {2008},
	note = {ISI Document Delivery No.: 293ZPTimes Cited: 5Cited Reference Count: 60Kang, Hyun-Seo Nelson, Mary L. Mackereth, Cameron D. Scharpf, Manuela Graves, Barbara J. McIntosh, Lawrence P.},
	month = {Mar},
	pages = {636-646},
	type = {Article},
	abstract = {Using NMR spectroscopy, we identified and characterized a previously unrecognized structured domain near the N-terminus (residues 35-121) of the ETS family transcription factor GABP alpha. The monomeric domain folds as a five-stranded beta-sheet crossed by a distorted helix. Although globally resembling ubiquitin, the GABP(x fragment differs in its secondary structure topology and thus appears to represent a new protein fold that we term the OST (On-SighT) domain. The surface of the GABP alpha OST domain contains two predominant clusters of negatively-charged residues suggestive of electrostatically driven interactions with positively-charged partner proteins. Following a best-candidate approach to identify such a partner, we demonstrated through NMR-monitored titrations and glutathione S-transferase pulldown assays that the OST domain binds to the CH1 and CH3 domains of the co-activator histone acetyltransferase CBP/p300. This provides a direct structural link between GABP and a central component of the transcriptional machinery. (C) 2008 Elsevier Ltd. All rights reserved.},
	keywords = {BACKBONE DYNAMICS, C-13-LABELED PROTEINS, CREB-BINDING-PROTEIN, ESCHERICHIA-COLI, HIGH-RESOLUTION, HYPOXIA-INDUCIBLE FACTOR-1-ALPHA, LARGER PROTEINS, NEUROMUSCULAR-JUNCTION, NMR, NMR EXPERIMENTS, protein-protein interaction, RESIDUAL DIPOLAR COUPLINGS, SPECTROSCOPY, TRANSCRIPTION FACTOR, UBIQUITIN},
	isbn = {0022-2836},
	url = {<Go to ISI>://000255374200006},
	author = {Kang, H. S. and Nelson, M. L. and Mackereth, C. D. and Scharpf, M. and Graves, B. J. and McIntosh, L. P.}
}
@article {2026,
	title = {Mechanisms of solute orientational order in nematic liquid crystals},
	journal = {Journal of Chemical Physics},
	volume = {128},
	number = {16},
	year = {2008},
	note = {ISI Document Delivery No.: 295DXTimes Cited: 7Cited Reference Count: 51Burnell, E. Elliott ter Beek, Leon C. Sun, Zhengmin},
	month = {Apr},
	pages = {10},
	type = {Article},
	abstract = {The order parameters of a number of different solutes dissolved in a number of different nematic liquid-crystal solvents are measured and compared. It is shown that the order parameters can all be rationalized with the ansatz that there exist two independent ordering mechanisms operating in the liquid crystals employed. With this ansatz it is possible to fit the experimental order parameters to better than 5\%. This opens the possibility of the accurate prediction of order parameters in ordered liquids. (c) 2008 American Institute of Physics.},
	keywords = {ELECTRIC-DIPOLE INTERACTIONS, electrostatic, FIELD GRADIENT, interactions, KRISTALLINFLUSSIGEN PHASE, MEAN TORQUE, MOLECULAR-STRUCTURE, MOLEKULAR-STATISTISCHE THEORIE, MONTE-CARLO SIMULATIONS, NMR, SOLVENTS},
	isbn = {0021-9606},
	url = {<Go to ISI>://000255456300083},
	author = {Burnell, E. E. and ter Beek, L. C. and Sun, Z. M.}
}
@article {2082,
	title = {Powder neutron diffraction determination of the structure of the o-xylene/zeolite ZSM-5 complex},
	journal = {Microporous and Mesoporous Materials},
	volume = {112},
	number = {1-3},
	year = {2008},
	note = {ISI Document Delivery No.: 313AKTimes Cited: 1Cited Reference Count: 41Fyfe, Colin A. Lee, J. S. Joseph Cranswick, Lachlan M. D. Swainson, Ian},
	month = {Jul},
	pages = {299-307},
	type = {Article},
	abstract = {The structure of the complex of zeolite ZSM-5 (MFI) and ortho-xylene at a loading of four molecules per u.c. has been solved using powder neutron diffraction techniques and perdeuterated xylene. The structure is orthorhombic and the position and orientation of the organic is identical to that found previously by solid state NMR, attesting to the reliability of the NMR technique as a complement to diffraction methods. The maximum and minimum oxygen-oxygen distances of the elliptical 10-membered ring where the ortho-xylene is located are 8.86 angstrom and 7.45 angstrom, respectively, compared to corresponding distances of 9.13 angstrom and 7.32 angstrom found previously for the para-isomer, reflecting the different adjustments of the framework to the different sizes and shapes of the two guest molecules. (C) 2007 Elsevier Inc. All rights reserved.},
	keywords = {CRYSTAL, FLUORIDE IONS, FRAMEWORK, HOST, LOCATION, method, MFI zeolite, NMR, ortho-xylene, PARA-XYLENE, powder neutron diffraction, SORBATE, X-RAY-DIFFRACTION, ZEOLITE ZSM-5},
	isbn = {1387-1811},
	url = {<Go to ISI>://000256713300034},
	author = {Fyfe, C. A. and Lee, J. S. J. and Cranswick, L. M. D. and Swainson, I.}
}
@article {2169,
	title = {Serendipitous syntheses of Rh(H)(2)Cl(PRPh2)(3) complexes, and their crystal structures, where R = Me, Cy (cyclohexyl)},
	journal = {Inorganica Chimica Acta},
	volume = {361},
	number = {7},
	year = {2008},
	note = {ISI Document Delivery No.: 304ETTimes Cited: 4Cited Reference Count: 40Lorenzini, Fabio Patrick, Brian O. James, Brian R.},
	month = {May},
	pages = {2123-2130},
	type = {Article},
	abstract = {Reactions of RhCl(cod)(THP) (cod = 1,5-cyclooctadiene; THP = P(CH2OH)(3)) with PMePh2 or PCyPh2 (Cy = cyclohexyl) in acetone/MeOH solution under H-2 surprisingly form the complexes cis,mer-Rh(H)Cl-2(PRPh2)(3) (R = Me or Cy); both complexes are characterized by crystallography (the first structures in which the hydride ligands of such dihydrido-chloro-trisphosphine complexes have been located), and by detailed H-1 and P-31 NMR spectroscopy. The key role of the THP in the observed chemistry is discussed. (C) 2007 Elsevier B.V. All rights reserved.},
	keywords = {CRYSTALLOGRAPHY, ETHYLENE, EXCHANGE, HOMOGENEOUS CATALYTIC HYDROGENATION, hydride, hydride complexes, NMR, PARAHYDROGEN-INDUCED POLARIZATION, PHOSPHINE COMPLEXES, rhodium, RHODIUM(I), SPECTROSCOPY, TERTIARY PHOSPHINES, WATER, WILKINSONS CATALYST},
	isbn = {0020-1693},
	url = {<Go to ISI>://000256093500040},
	author = {Lorenzini, F. and Patrick, B. O. and James, Brian R.}
}
@article {1594,
	title = {Dideuterium as solute in nematic liquid crystals},
	journal = {Chemical Physics Letters},
	volume = {426},
	number = {1-3},
	year = {2006},
	note = {ISI Document Delivery No.: 067AMTimes Cited: 6Cited Reference Count: 14ter Beek, Leon C. Burnell, E. Elliott},
	month = {Jul},
	pages = {96-99},
	type = {Article},
	abstract = {Deuteron NMR experiments on dideuterium dissolved in the nematic liquid-crystal solvents 7CB, CCH7, MBBA and PCH7 are reported as a function of temperature. The results are analysed in terms of the average solvent electric field gradient anisotropy (efg) felt by D-2 which is positive with respect to the director in 7CB, CCH7 and PCH7 and negative in MBBA. The order parameter of D-2 is to a large extent rationalized in terms of the interaction between this solvent efg and the solute D-2 molecular quadrupole moment, and its sign is the same as that of the efg. (c) 2006 Elsevier B.V. All rights reserved.},
	keywords = {MOLECULAR-HYDROGEN, NMR, orientational order, SOLVENTS},
	isbn = {0009-2614},
	url = {<Go to ISI>://000239272400020},
	author = {ter Beek, L. C. and Burnell, E. E.}
}
@article {1443,
	title = {Lanthanide(III) and group 13 metal ion complexes of tripodal amino phosphinate ligands},
	journal = {Dalton Transactions},
	number = {1},
	year = {2006},
	note = {ISI Document Delivery No.: 993PUTimes Cited: 2Cited Reference Count: 23},
	pages = {31-38},
	type = {Article},
	abstract = {The tripodal amino-phosphinate ligands, tris(4-(phenylphosphinato)-3-benzyl-3-azabutyl) amine (H(3)ppba center dot 2HCl center dot H2O) and tris(4-(phenylphosphinato)-3-azabutyl) amine (H(3)ppa center dot HCl center dot H2O) were synthesized and reacted with Al3+, Ga3+, In3+ and the lanthanides (Ln(3+)). At 2 : 1 H(3)ppba to metal ratios, complexes of the type [M(H(3)ppba)(2)](3+) (M = Al3+, Ga3+, In3+, Ho3+-Lu3+) were isolated. The bicapped [Ga(H(3)ppba)(2)](NO3)(2)Cl center dot 3CH(3)OH was structurally characterized and was shown indirectly by various techniques to be isostructural with the other [M(H(3)ppba)(2)](3+) complexes. Also, at 2:1 H(3)ppba to metal ratios, complexes of the type [M(H(4)ppba)(2)](5+) (M = La3+-Tb3+) were characterized, and the X-ray structure of [Gd(H(4)ppba)(2)](NO3)(4)Cl center dot 3CH(3)OH was determined. At 1:1 H(3)ppba to metal ratios, complexes of the type [M(H(4)ppba)](4+) (M = La3+-Er3+) were isolated and characterized. Elemental analysis and spectroscopic evidence supported the formation of a 1:1 monocapped complex. Reaction of 1:1 ratios of H(3)ppa with Ln(3+) and In3+ yielded complexes of the type [M(H(3)ppa)](3+) (M = La3+-Yb3+) but with Ga3+, complex of the type [Ga(ppa)]center dot 3H(2)O was obtained. Reaction of 1:1 ratios of H(3)ppa with Ln(3+) and In3+ yielded complexes of the type [M(H(3)ppa)](3+) (M = La3+-Yb3+) but with Ga3+ a neutral complex [Ga(ppa)]center dot 3H(2)O was obtained. The formation of an encapsulated 1:1 complex is supported by elemental analysis and spectroscopic evidence.},
	keywords = {ACID, BEARING, CIRCULARLY-POLARIZED LUMINESCENCE, CONTRAST AGENTS, MAGNETIC-RESONANCE, NMR, RELAXOMETRY},
	isbn = {1477-9226},
	url = {<Go to ISI>://000233968200004},
	author = {Kovacs, M. S. and Monga, V. and Patrick, B. O. and Orvig, Chris}
}
@article {1443,
	title = {Lanthanide(III) and group 13 metal ion complexes of tripodal amino phosphinate ligands},
	journal = {Dalton Transactions},
	number = {1},
	year = {2006},
	note = {ISI Document Delivery No.: 993PUTimes Cited: 2Cited Reference Count: 23},
	pages = {31-38},
	type = {Article},
	abstract = {The tripodal amino-phosphinate ligands, tris(4-(phenylphosphinato)-3-benzyl-3-azabutyl) amine (H(3)ppba center dot 2HCl center dot H2O) and tris(4-(phenylphosphinato)-3-azabutyl) amine (H(3)ppa center dot HCl center dot H2O) were synthesized and reacted with Al3+, Ga3+, In3+ and the lanthanides (Ln(3+)). At 2 : 1 H(3)ppba to metal ratios, complexes of the type [M(H(3)ppba)(2)](3+) (M = Al3+, Ga3+, In3+, Ho3+-Lu3+) were isolated. The bicapped [Ga(H(3)ppba)(2)](NO3)(2)Cl center dot 3CH(3)OH was structurally characterized and was shown indirectly by various techniques to be isostructural with the other [M(H(3)ppba)(2)](3+) complexes. Also, at 2:1 H(3)ppba to metal ratios, complexes of the type [M(H(4)ppba)(2)](5+) (M = La3+-Tb3+) were characterized, and the X-ray structure of [Gd(H(4)ppba)(2)](NO3)(4)Cl center dot 3CH(3)OH was determined. At 1:1 H(3)ppba to metal ratios, complexes of the type [M(H(4)ppba)](4+) (M = La3+-Er3+) were isolated and characterized. Elemental analysis and spectroscopic evidence supported the formation of a 1:1 monocapped complex. Reaction of 1:1 ratios of H(3)ppa with Ln(3+) and In3+ yielded complexes of the type [M(H(3)ppa)](3+) (M = La3+-Yb3+) but with Ga3+, complex of the type [Ga(ppa)]center dot 3H(2)O was obtained. Reaction of 1:1 ratios of H(3)ppa with Ln(3+) and In3+ yielded complexes of the type [M(H(3)ppa)](3+) (M = La3+-Yb3+) but with Ga3+ a neutral complex [Ga(ppa)]center dot 3H(2)O was obtained. The formation of an encapsulated 1:1 complex is supported by elemental analysis and spectroscopic evidence.},
	keywords = {ACID, BEARING, CIRCULARLY-POLARIZED LUMINESCENCE, CONTRAST AGENTS, MAGNETIC-RESONANCE, NMR, RELAXOMETRY},
	isbn = {1477-9226},
	url = {<Go to ISI>://000233968200004},
	author = {Kovacs, M. S. and Monga, V. and Patrick, B. O. and Orvig, Chris}
}
@article {1524,
	title = {Unambiguous determination of the ionization state of a glycoside hydrolase active site lysine by H-1-N-15 heteronuclear correlation spectroscopy},
	journal = {Journal of the American Chemical Society},
	volume = {128},
	number = {48},
	year = {2006},
	note = {ISI Document Delivery No.: 110GSTimes Cited: 15Cited Reference Count: 15Poon, David K. Y. Schubert, Mario Au, Jason Okon, Mark Withers, Stephen G. McIntosh, Lawrence P.},
	month = {Dec},
	pages = {15388-15389},
	type = {Article},
	keywords = {AMINO-ACIDS, beta, EXCHANGE, MAGNETIC-RESONANCE, NMR, PROTEINS},
	isbn = {0002-7863},
	url = {<Go to ISI>://000242367000018},
	author = {Poon, D. K. Y. and Schubert, M. and Au, J. and Okon, M. and Withers, S. G. and McIntosh, L. P.}
}
@article {1272,
	title = {A convenient way of making arsoxanes (RAsO)(n), X-ray crystal structure of (m-F3CC6H4AsO)(4)},
	journal = {Applied Organometallic Chemistry},
	volume = {19},
	number = {1},
	year = {2005},
	note = {ISI Document Delivery No.: 893NZTimes Cited: 2Cited Reference Count: 22},
	month = {Jan},
	pages = {129-131},
	type = {Article},
	abstract = {The reactions of RLi (R = t-Bu, m-F3CC6H4) with bis(dimethylamino)chloroarsine in diethyl ether at room temperature result in the formation of t-butyl-bis(dimethylamino)arsine (1) and m-trifluoromethylphenyl-bis(dimethylamino)arsine (2). Compounds 1 and 2 were hydrolysed in water solution in the presence of sodium carbonate to give the oxides (t-BuAsO)(n) (3) and (m-F3CC6H4AsO)(n) (4) respectively. The X-ray crystal structure of 4 shows the molecule to be cyclotetrameric with pyramidal arsenic. Copyright (C) 2004 John Wiley Sons, Ltd.},
	keywords = {ALKYLCYCLOARSOXANES, arsenic, ARSINE, arsine oxide, crystal structure, m-trifluromethylphenylarsine oxide, m-trifluromethylphenylarsoxane, NMR, RING, t-butylarsarsoxane, t-butylarsine oxide},
	isbn = {0268-2605},
	url = {<Go to ISI>://000226727800024},
	author = {Sun, H. S. and Patrick, B. O. and Cullen, W. R.}
}
@article {1296,
	title = {Dynamic C-13 NMR studies of ligand exchange in linear (d(10)) silver(I) and gold(I) and square-planar (d(8)) rhodium(I) homoleptic metal carbonyl cations in superacidic media},
	journal = {Magnetic Resonance in Chemistry},
	volume = {43},
	number = {7},
	year = {2005},
	note = {ISI Document Delivery No.: 936FUTimes Cited: 0Cited Reference Count: 21},
	month = {Jul},
	pages = {520-527},
	type = {Article},
	abstract = {The dynamic CO exchange of the monovalent metal carbonyl cations [Ag((CO)-C-13)](+), [Au((CO)-C-13)(2)](+)-Au((CO)-C-13) SO3F and [Rh((CO)-C-12)(4-x)((CO)-C-13)(x)](+) (x <= 1) in superacidic solutions was studied by variable-temperature C-13 NMR methods. The exchange rates are strongly dependent on the acidity of the solvent, the concentration of metal carbonyl cations and temperature. Whereas a suitable exchange rate of the Ag(I) system is only accessible in magic acid (HSO3F-SbF5), the more stable Au(I) and Rh(I) systems were studied in the less acidic fluorosulfuric acid. Selected solutions of Ag(I), Rh(I) and Au(I) yielded activation barriers Delta G* of 42.7, 43.5, and 56.2 kJ mol(-1) respectively. Copyright (c) 2005 John Wiley \& Sons, Ltd.},
	keywords = {C-13 NMR, CO exchange, CRYSTAL, dynamic NMR, fluorosulfuric acid, GOLD, HINDERED INTERNAL ROTATION, HSO3F-SBF5, magic acid, metal carbonyl cations, NMR, NUCLEAR-MAGNETIC-RESONANCE, rhodium, silver, UNDECAFLUORODIANTIMONATE(V), VIBRATIONAL-SPECTRA},
	isbn = {0749-1581},
	url = {<Go to ISI>://000229841700003},
	author = {von Ahsen, B. and Bach, C. and Balzer, G. and Bley, B. and Bodenbinder, M. and Hagele, G. and Willner, H. and Aubke, F.}
}
@article {1068,
	title = {NMR as a tool in the investigation of fundamental problems in ordered liquids},
	journal = {Solid State Nuclear Magnetic Resonance},
	volume = {28},
	number = {2-4},
	year = {2005},
	note = {ISI Document Delivery No.: 998NHTimes Cited: 9Cited Reference Count: 49},
	month = {Sep},
	pages = {73-90},
	type = {Article},
	abstract = {An overview is presented of modern NMR techniques and a variety of experimental and theoretical tools employed in the study of solutes dissolved in liquid crystals. The NMR techniques involve multiple quantum and spectral subtraction methods, In addition, various experimental and theoretical tools are discussed, including: the theoretical background of observed order parameters; the use of,magic mixtures{\textquoteright} to separate orientational contributions; the reorientation-vibration interaction; the use of model calculations based on size and shape of the various solutes; and the use of computer simulations. Applications to the benchmark probe molecules hydrogen, methane, ethane, and butane and their isotopomers are treated. (c) 2005 Elsevier Inc. All rights reserved.},
	keywords = {ANISOTROPIC LIQUIDS, butane, ethane, H-2 NMR, HYDROGEN, INTERNAL-ROTATION, liquid crystal, METHANE, MOLECULES, MOLEKULAR-STATISTISCHE THEORIE, MULTIPLE-QUANTUM NMR, NEMATISCHEN KRISTALLINFLUSSIGEN PHASE, NMR, NUCLEAR-MAGNETIC-RESONANCE, order parameter, orientational order, PROTON DIPOLAR COUPLINGS, SMALL CHAIN},
	isbn = {0926-2040},
	url = {<Go to ISI>://000234325100003},
	author = {Burnell, E. E. and de Lange, C. A.}
}
@inbook {855,
	title = {Solid state NMR studies of the hydration of molecular sieve AlPO-36},
	booktitle = {Recent Advances in the Science and Technology of Zeolites and Related Materials, Pts a - C},
	series = {Studies in Surface Science and Catalysis},
	volume = {154},
	year = {2004},
	note = {ISI Document Delivery No.: BBR47Times Cited: 1Cited Reference Count: 4Proceedings Paper14th International Zeolite Conference on Recent Advances in the Science and Technology of Zeolites and Related MaterialsAPR 25-30, 2004Cape Town, SOUTH AFRICASARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS},
	pages = {1238-1245},
	publisher = {Elsevier Science Bv},
	organization = {Elsevier Science Bv},
	address = {Amsterdam},
	abstract = {Al-27 and (31)p solid state MAS NMR spectra obtained at high field for the aluminophosphate AIPO-36 show that the hydration process produces both 5- and 6-coordinate Al sites. Al-27 MQMAS spectra of the hydrated form show at least four tetrahedral aluminium sites, as well as one octahedral and one five coordinate site. 2D Al-27 /P-31 INEPT experiments show multiple connectivitics between these sites in the hydrated form but the spectra are too complex for a full and unambiguous interpretation and complementary diffraction data will have to be obtained for a more complete understanding of the hydration mechanism.},
	keywords = {AlPO-36, aluminophosphate molecular sieves, NMR},
	isbn = {0167-29910-444-51805-3},
	url = {<Go to ISI>://000227357201012},
	author = {Fyfe, C. A. and Bretherton, J. L. and Skibsted, J. and Zahedi-Niaki, M. H. and Kalliaguine, S.},
	editor = {VanSteen, E. and Claeys, M. and Callanan, L. H.}
}
@article {935,
	title = {Stereochemical assignment in acyclic lipids across long distance by circular dichroism: Absolute stereochemistry of the aglycone of caminoside A},
	journal = {Angewandte Chemie-International Edition},
	volume = {43},
	number = {44},
	year = {2004},
	note = {ISI Document Delivery No.: 874FTTimes Cited: 14Cited Reference Count: 30},
	pages = {5946-5951},
	type = {Article},
	keywords = {AGENT, ANTIVIRAL ANTIBIOTICS, B-1, CHROMOPHORES, circular dichroism, CONFIGURATION ANALYSIS, CYCLOVIRACIN, glycolipids, LIPOSOMES, MOSHER METHOD, natural products, NMR, PHYSICOCHEMICAL, PROPERTIES, SECONDARY ALCOHOLS, SPIN-COUPLING CONSTANTS, STEREOCHEMISTRY},
	isbn = {1433-7851},
	url = {<Go to ISI>://000225337000017},
	author = {MacMillan, J. B. and Linington, R. G. and Andersen, R. J. and Molinski, T. F.}
}
@article {685,
	title = {An analytical formulation of CPMAS},
	journal = {Solid State Nuclear Magnetic Resonance},
	volume = {23},
	number = {1-2},
	year = {2003},
	note = {ISI Document Delivery No.: 662PWTimes Cited: 4Cited Reference Count: 21},
	month = {Feb-Mar},
	pages = {28-49},
	type = {Article},
	abstract = {An exact expression for the cross polarization between two spin1/2 particles is derived from the quantum Liouville equation. This is given in the form of two integrodifferential equations. These can be solved exactly in the static case (no sample spinning) and a powder average easily performed numerically. With magic-angle spinning, the neglect of certain interference terms simplifies the numerical calculation. A further assumption decoupling the calculation of the sidebands gives a very simple formula that is capable of giving a qualitative interpretation of all experimental observations. Examples are given illustrating typical buildup curves and CPMAS matching profiles. (C) 2002 Elsevier Science (USA). All rights reserved.},
	keywords = {CPMAS, cross polarization, CROSS-POLARIZATION EXPERIMENTS, DYNAMICS, equation, generalized master equation, magic-angle spinning, MAGNETIC-RESONANCE, NMR, quantum Liouville, SOLIDS, TRANSIENT OSCILLATIONS},
	isbn = {0926-2040},
	url = {<Go to ISI>://000181957200003},
	author = {Marica, F. and Snider, R. F.}
}
@article {610,
	title = {Influence of F content on the composition of Al-rich synthetic phlogopite: Part II. Probing the structural arrangement of aluminum in tetrahedral and octahedral layers by Al-27 MQMAS and H-1/F-19-Al-27 HETCOR and REDOR experiments},
	journal = {American Mineralogist},
	volume = {88},
	number = {7},
	year = {2003},
	note = {ISI Document Delivery No.: 699FDTimes Cited: 10Cited Reference Count: 28},
	month = {Jul},
	pages = {1046-1054},
	type = {Article},
	abstract = {The influence of F substitution on the local structure of Al in the tetrahedral and octahedral sheets of synthetic Al-rich phlogopite samples with nominal gel compositions of K(Mg3-xAlx)[Al1+xSi3-xO10] (OH)(y)(F)(2-y) between 0.0 less than or equal to x less than or equal to 0.8 and 0.5 less than or equal to y less than or equal to 1.8, was studied by Al-27 MAS, MQMAS, {H-1/F-19} {\textendash}> Al-27 2D CPMAS (HETCOR) and {H-1/F-19} Al-27 REDOR solid-state NMR and by IR spectroscopy. Changes in intensity of the absorption bands in the OH-stretching region of the IR spectra clearly indicate the incorporation of octahedral Al. Signals from the different phases can be separated in the Al-27 MQMAS NMR spectra by generation of an isotropic dimension in F1. The Al-27 quadrupolar parameters of the four phases were estimated from Al-27 MAS NMR spectra obtained at 104.26 and 208.42 MHz. The quadrupolar coupling constant and isotropic chemical shift increases with increasing Al content for the Al-IV site in phlogopite. The Al-VI site shows a clear increase of the asymmetry parameter and C-Q with increasing F content. The estimated Al-27 signal areas show the lowest amount of impurity phases at high OH contents and a stabilization of Al-VI sites by hydroxyl groups. The {H-1} {\textendash}> Al-27 2D CPMAS (HETCOR) NMR experiment at short contact times provides information about site neighborhoods of tetrahedral Al sites and Mg3OH as well as Mg2AlOH sites, whereas magnetization is only transferred to the octahedral At sites from hydroxyl groups in Mg2AlOH sites. The {F-19} {\textendash}> Al-27 2D CPMAS (HETCOR) NMR spectrum is dominated by Al-IV sites coupled to the Mg3F complex in phlogopite. Resonances from Mg2AlF complexes are not observed. Finally, the {H-1/F-19} Al-27 REDOR experiments support the results of the 2D CPMAS (HETCOR) experiments.},
	keywords = {ANGLE-SPINNING NMR, DOUBLE-RESONANCE, F-19 MAS-NMR, FLUORINE, HIGH-FIELD, NMR, QUADRUPOLAR NUCLEI, SI-29, SOLID-STATE NMR, SPECTRA, SUBSTITUTION},
	isbn = {0003-004X},
	url = {<Go to ISI>://000184045300013},
	author = {Fechtelkord, M. and Behrens, H. and Holtz, F. and Bretherton, J. L. and Fyfe, C. A. and Groat, L. A. and Raudsepp, M.}
}
@article {514,
	title = {Simultaneous selective detection of multiple quantum spectra},
	journal = {Journal of Magnetic Resonance},
	volume = {155},
	number = {2},
	year = {2002},
	note = {ISI Document Delivery No.: 560GETimes Cited: 8Cited Reference Count: 11},
	month = {Apr},
	pages = {251-256},
	type = {Article},
	abstract = {A three-dimensional multiple-quantum NMR experiment that produces individual spectra of all quantum orders is described. The separation of different quantum orders is accomplished via Fourier transformation with respect to the phase of the first two pulses of a generic three-pulse multiple-quantum sequence. This dramatically reduces the time required to obtain several selectively detected spectra and enhances the sensitivity and digital resolution from that obtained using the original two-dimensional technique. The experiment is demonstrated on the protons of para-chlorotoluene dissolved in the nematic liquid crystal Merck ZLI-1132. (C) 2002 Elsevier Science (USA).},
	keywords = {liquid crystal, LIQUID-CRYSTAL SOLVENTS, MQNMR, multiple, nematic, NMR, orientational order, quantum coherence, SPECTROSCOPY},
	isbn = {1090-7807},
	url = {<Go to ISI>://000176073700006},
	author = {Syvitski, R. T. and Burlinson, N. and Burnell, E. E. and Jeener, J.}
}
@article {461,
	title = {Synthesis and conformational dynamics of ortho-xylyl-bridged-[4]cavitands},
	journal = {Tetrahedron},
	volume = {58},
	number = {4},
	year = {2002},
	note = {ISI Document Delivery No.: 515QLTimes Cited: 10Cited Reference Count: 24},
	month = {Jan},
	pages = {787-798},
	type = {Article},
	abstract = {ortho-Xylyl-[4]cavitands 2 to 6 were synthesized from bromoresorcin[4] arenes 1. Cavitands 2 to 6 show C-4nu symmetry in their H-1 NMR spectra at higher temperatures. Dynamic H-1 NMR studies of 2 to 6 indicate the C-4nu symmetry is due to fast interconversion of rectangular C-2nu isomers. This is supported by the crystal structure of 2a, which shows a C-2nu rectangular structure. The activation energy barriers for 2a and 2b were measured by quantitative 1D NOESY (EXSY) experiments. The results were analyzed by the initial rate approximation and matrix calculations. The activation energy barrier was found to depend strongly on the size of the upper rim group (Br, H, OH, CN). In addition, replacing the phenolic proton of tetrol derivatives 4a and 4b with metal ions raises the energy barrier further, likely via bridging metal cations. The two tetrabromo compounds (2a and 2b) reveal a sensitivity of the activation barrier to the feet of the cavitands. Cavitand 6 may act as a hub for radially expanded cavitands. The advantages of the 1D NOESY experiments over the more commonly used two-dimensional experiments are discussed. (C) 2002 Elsevier Science Ltd. All rights reserved.},
	keywords = {1D NOESY (EXSY), CARCEPLEXES, CAVITANDS, CHEMICAL-EXCHANGE, DEEP-CAVITY CAVITANDS, dynamic H-1 NMR, EXCHANGE, HEMICARCEPLEXES, KINETICS, MAGNETIC-RESONANCE SPECTROSCOPY, NMR},
	isbn = {0040-4020},
	url = {<Go to ISI>://000173506800019},
	author = {Naumann, C. and Patrick, B. O. and Sherman, J. C.}
}
@article {374,
	title = {Tris(trifluoromethyl)borane carbonyl, (CF3)(3)BCO - Synthesis, physical, chemical and spectroscopic properties, gas phase, and solid state structure},
	journal = {Journal of the American Chemical Society},
	volume = {124},
	number = {51},
	year = {2002},
	note = {ISI Document Delivery No.: 628QATimes Cited: 49Cited Reference Count: 86},
	month = {Dec},
	pages = {15385-15398},
	type = {Article},
	abstract = {Tris(trifluoromethyl)borane carbonyl, (CF3)(3)BCO, is obtained in high yield by the solvolysis of K[B(CF3)(4)] in concentrated sulfuric acid. The in situ hydrolysis of a single bonded CF3 group is found to be a simple, unprecedented route to a new borane carbonyl. The related, thermally unstable borane carbonyl, (C6F5)(3)BCO, is synthesized for comparison purposes by the isolation of (C6F5)(3)B in a matrix of solid CO at 16 K and subsequent evaporation of excess CO at 40 K. The colorless liquid and vapor of (CF3)3BCO decomposes slowly at room temperature. In the gas phase t(1/2) is found to be 45 min. In the presence of a large excess of (CO)-C-13, the carbonyl substituent at boron undergoes exchange, which follows a first-order rate law. Its temperature dependence yields an activation energy (EA) of 112 kJ mol(-1). Low-pressure flash thermolysis of (CF3)3BCO with subsequent isolation of the products in low-temperature matrixes, indicates a lower thermal stability of the (CF3)3B fragment, than is found for (CF3)3BCO. Toward nucleophiles (CF3)3BCO reacts in two different ways: Depending on the nucleophilicity of the reagent and the stability of the adducts formed, nucleophilic substitution of CO or nucleophilic addition to the C atom of the carbonyl group are observed. A number of examples for both reaction types are presented in an overview. The molecular structure of (CF3)(3)BCO in the gas phase is obtained by a combined microwave-electron diffraction analysis and in the solid state by single-crystal X-ray diffraction. The molecule possesses C3 symmetry, since the three CF3 groups are rotated off the two possible positions required for C3, symmetry. All bond parameters, determined in the gas phase or in the solid state, are within their standard deviations in fair agreement, except for internuclear distances most noticeably the B-CO bond lengths, which is 1.69(2) Angstrom in the solid state and 1.617(12) Angstrom in the gas phase. A corresponding shift of nu(CO) from 2267 cm(-1) in the solid state to 2251 cm-1 in the gas phase is noted in the vibrational spectra. The structural and vibrational study is supported by DFT calculations, which provide, in addition to the equilibrium structure, confirmation of experimental vibrational wavenumbers, IR-band intensities, atomic charge distribution, the dipole moment, the B-CO bond energy, and energies for the elimination of CF2 from (CF3)(x)BF3-x1 = 1-3. In the vibrational analysis 21 of the expected 26 fundamentals are observed experimentally. The B-11-, C-13-, and F-19-NMR data, as well as the structural parameters of (CF3)(3)BCO, are compared with those of related compounds.},
	keywords = {= F, COMPLEXES, CRYSTAL, DERIVATIVES, IR, MICROWAVE-SPECTRUM, MOLECULAR-STRUCTURES, NMR, UNDECAFLUORODIANTIMONATE(V), X-RAY-DIFFRACTION},
	isbn = {0002-7863},
	url = {<Go to ISI>://000180006600046},
	author = {Finze, M. and Bernhardt, E. and Terheiden, A. and Berkei, M. and Willner, H. and Christen, D. and Oberhammer, H. and Aubke, F.}
}
@article {5098,
	title = {Dissecting the electrostatic interactions and pH-dependent activity of a family 11 glycosidase},
	journal = {Biochemistry},
	volume = {40},
	number = {34},
	year = {2001},
	note = {ISI Document Delivery No.: 466CYTimes Cited: 56Cited Reference Count: 50},
	month = {Aug},
	pages = {10115-10139},
	type = {Article},
	abstract = {Previous studies of the low molecular mass family 11 xylanase from Bacillus circulans show that the ionization state of the nucleophile (GIu78, pK(a) 4.6) and the acid/base catalyst (Glu 172, pK(a) 6.7) gives rise to its pH-dependent activity profile. Inspection of the crystal structure of BCX reveals that Glu78 and Glu172 are in very similar environments and are surrounded by several chemically equivalent and highly conserved active site residues. Hence, there are no obvious reasons why their apparent pKa values are different. To address this question, a mutagenic approach was implemented to determine what features establish the pKa values (measured directly by C-13 NMR and indirectly by pH-dependent activity profiles) of these two catalytic carboxylic acids. Analysis of several BCX variants indicates that the ionized form of Glu78 is preferentially stabilized over that of Glu 172 in part by stronger hydrogen bonds contributed by two well-ordered residues, namely, Tyr69 and Gln127. In addition, theoretical pKa calculations show that Glu78 has a lower pKa value than Glu 172 due to a smaller desolvation energy and more favorable background interactions with permanent partial charges and ionizable groups within the protein. The pKa value of Glu172 is in turn elevated due to electrostatic repulsion from the negatively charged glutamate at position 78. The results also indicate that all of the conserved active site residues act concertedly in establishing the pKa values of Glu78 and Glu 172, with no particular residue being singly more important than any of the others. In general, residues that contribute positive charges and hydrogen bonds serve to lower the pKa values of Glu78 and Glu172. The degree to which a hydrogen bond lowers a pKa value is largely dependent on the length of the hydrogen bond (shorter bonds lower pKa values more) and the chemical nature of the donor (COOH > OH > CONH2). In contrast, neighboring carboxyl groups can either lower or raise the pKa values of the catalytic glutamic acids depending upon the electrostatic linkage of the ionization constants of the residues involved in the interaction. While the pH optimum of BCX can be shifted from -1.1 to +0.6 pH units by mutating neighboring residues within the active site, activity is usually compromised due to the loss of important ground and/or transition state interactions. These results suggest that the pH optima of an enzyme might be best engineered by making strategic amino acid substitutions, at positions outside of the "core" active site, that electrostatically influence catalytic residues without perturbing their immediate structural environment.},
	keywords = {ASSIGNMENTS, BACILLUS-CIRCULANS XYLANASE, CATALYSIS, GLYCOSYL-ENZYME INTERMEDIATE, KINETIC-ANALYSIS, MASS-SPECTROMETRY, MECHANISMS, NMR, PK(A), PROTEIN, SITE NUCLEOPHILE, structures},
	isbn = {0006-2960},
	url = {<Go to ISI>://000170627800014},
	author = {Joshi, M. D. and Sidhu, G. and Nielsen, J. E. and Brayer, G. D. and Withers, S. G. and McIntosh, L. P.}
}
@article {5154,
	title = {Expanding cavitand chemistry: The preparation and characterization of [n]cavitands with n >= 4},
	journal = {Chemistry-a European Journal},
	volume = {7},
	number = {8},
	year = {2001},
	note = {ISI Document Delivery No.: 426VFTimes Cited: 21Cited Reference Count: 26},
	month = {Apr},
	pages = {1637-1645},
	type = {Article},
	abstract = {{The preparation of cavitands composed of 4, 5, 6, and 7 aromatic subunits ([n]cavitands},
	keywords = {CAVITANDS, chemical exchange, CHEMICAL-EXCHANGE, CHEMISTRY, HOST GUEST COMPLEXATION, host-guest chemistry, KINETICS, NMR, supramolecular},
	isbn = {0947-6539},
	url = {<Go to ISI>://000168368500009},
	author = {Naumann, C. and Roman, E. and Peinador, C. and Ren, T. and Patrick, B. O. and Kaifer, A. E. and Sherman, J. C.}
}
@article {5027,
	title = {Pressure-induced change in orientational order of solutes in liquid crystals},
	journal = {Chemical Physics Letters},
	volume = {337},
	number = {4-6},
	year = {2001},
	note = {ISI Document Delivery No.: 420BPTimes Cited: 1Cited Reference Count: 20},
	month = {Apr},
	pages = {248-254},
	type = {Article},
	abstract = {The H-1 and H-1 NMR spectroscopy of the nematic liquid crystal ZLI 1132 containing small amounts of the solutes 1,3,5- trichlorobenzene. p-dichlorobenzene and acetone was investigated as a function of the pressure of a mixture of molecular hydrogen and deuterium gases above the sample. A general increase of solute orientational order with pressure was observed. Differences in behavior of the orientational order of the hydrogens compared to the other solutes are discussed. (C) 2001 Elsevier Science B.V. All rights reserved.},
	keywords = {COMPUTER-SIMULATION, density, MAGNETIC-RESONANCE, MOLECULES, NEMATIC PHASE, NMR, SOLVENTS, TEMPERATURE-DEPENDENCE},
	isbn = {0009-2614},
	url = {<Go to ISI>://000167984300004},
	author = {Burnell, E. E. and de Lange, C. A. and Gaemers, S.}
}
@article {4780,
	title = {Analysis of the dynamic properties of Bacillus circulans xylanase upon formation of a covalent glycosyl-enzyme intermediate},
	journal = {Protein Science},
	volume = {9},
	number = {3},
	year = {2000},
	note = {ISI Document Delivery No.: 295XWTimes Cited: 16Cited Reference Count: 56},
	month = {Mar},
	pages = {512-524},
	type = {Article},
	abstract = {NMR spectroscopy was used to search for mechanistically significant differences in the local mobility of the main-chain amides of Bacillus circulans xylanase (BCX) in its native and catalytically competent covalent glycosyl-enzyme intermediate states. N-15 T-1, T-2, and N-15{H-1} NOE values were measured for similar to 120 out of 178 peptide groups in both the apo form of the protein and in BCX covalently modified at position Glu78 with a mechanism-based 2-deoxy-2-fluoro-beta-xylobioside inactivator. Employing the model-free formalism of Lipari and Szabo, the measured relaxation parameters were used to calculate a global correlation time ( tau(m)) for the protein in each form (9.2 +/- 0.2 ns for apo-BCX; 9.8 +/- 0.3 ns for the modified protein), as well as individual order parameters for the main-chain NH bond vectors. Average values of the order parameters for the protein in the apo and complexed forms were S-2 = 0.86 +/- 0.04 and S-2 = 0.91 +/- 0.04, respectively. No correlation is observed between these order parameters and the secondary structure, solvent accessibility, or hydrogen bonding patterns of amides in either form of the protein. These results demonstrate that the backbone of BCX is well ordered in both states and that formation of the,glycosyl-enzyme intermediate leads to little change, in any, in the dynamic properties of BCX on the time scales sampled by N-15-NMR relaxation measurements.},
	keywords = {ACTIVE-SITE NUCLEOPHILE, ANISOTROPIC ROTATIONAL, BACKBONE DYNAMICS, BINDING, BURIED NEUTRAL HISTIDINE, DIFFUSION, glucanase, GLYCOSYL-ENZYME INTERMEDIATE, MAGNETIC-RESONANCE RELAXATION, MODEL-FREE APPROACH, N-15 NMR RELAXATION, NMR, order parameter, PROTEIN, PROTEINS, relaxation dynamics, SIDE-CHAIN RESONANCES, STRUCTURE},
	isbn = {0961-8368},
	url = {<Go to ISI>://000085994800009},
	author = {Connelly, G. P. and Withers, S. G. and McIntosh, L. P.}
}
@article {4842,
	title = {Hydrogen bonding and catalysis: A novel explanation for how a single amino acid substitution can change the pH optimum of a glycosidase},
	journal = {Journal of Molecular Biology},
	volume = {299},
	number = {1},
	year = {2000},
	note = {ISI Document Delivery No.: 318NCTimes Cited: 96Cited Reference Count: 58},
	month = {May},
	pages = {255-279},
	type = {Article},
	abstract = {The pH optima of family 11 xylanases are well correlated with the nature of the residue adjacent to the acid/base catalyst. In xylanases that function optimally under acidic conditions, this residue is aspartic acid, whereas it is asparagine in those that function under more alkaline conditions. Previous studies of wild-type (WT) Bacillus circulans xylanase (BCX), with an asparagine residue at position 35, demonstrated that its pH-dependent activity follows the ionization states of the nucleophile Glu78 (pK(a) 4.6) and the acid/base catalyst Glu172 (pK(a) 6.7). As predicted from sequence comparisons, substitution of this asparagine residue with an aspartic acid residue (N35D BCX) shifts its pH optimum from 5.7 to 4.6, with an similar to 20 \% increase in activity. The bell-shaped pH-activity profile of this mutant enzyme follows apparent pK(a) values of 3.5 and 5.8. Based on C-13-NMR titrations, the predominant pK(a) values of its active-site carboxyl groups are 3.7 (Asp35), 5.7 (Glu78) and 8.4 (Glu172). Thus, in contrast to the WT enzyme, the pH-activity profile of N35D BCX appears to be set by Asp35 and Glu78. Mutational, kinetic, and structural studies of N35D BCX, both in its native and covalently modified 2-fluoro-xylobiosyl glycosyl-enzyme intermediate states, reveal that the xylanase still follows a double-displacement mechanism with Glu78 serving as the nucleophile. We therefore propose that Asp35 and Glu172 function together as the general acid/base catalyst, and that N35D BCX exhibits a "reverse protonation" mechanism in which it is catalytically active when Asp35, with the lower pK(a), is protonated, while Glu78, with the higher pK(a), is deprotonated. This implies that the mutant enzyme must have an inherent catalytic efficiency at least 100-fold higher than that of the parental WT, because only similar to 1\% of its population is in the correct ionization state for catalysis at its pH optimum. The increased efficiency of N35D BCX, and by inference all "acidic" family 11 xylanases, is attributed to the formation of a short (2.7 Angstrom) hydrogen bond between Asp35 and Glu172, observed in the crystal structure of the glycosyl-enzyme intermediate of this enzyme, that will substantially stabilize the transition state for glycosyl transfer. Such a mechanism may be much more commonly employed than is generally realized, necessitating careful analysis of the pH-dependence of enzymatic catalysis. (C) 2000 Academic Press.},
	keywords = {3-DIMENSIONAL STRUCTURE, 4-BETA-XYLANASES, ACTIVE-SITE, BACILLUS-CIRCULANS XYLANASE, CYCLODEXTRIN GLYCOSYLTRANSFERASE, electrostatics, ENDO-1, GLYCOSYL-ENZYME INTERMEDIATE, ISOTOPE, MOLECULAR-WEIGHT, NMR, NUCLEAR-MAGNETIC-RESONANCE, nucleophile, PANCREATIC ALPHA-AMYLASE, pH-dependent enzyme mechanism, SHIFT, TRICHODERMA-REESEI, X-RAY CRYSTALLOGRAPHY, X-ray structure},
	isbn = {0022-2836},
	url = {<Go to ISI>://000087289400019},
	author = {Joshi, M. D. and Sidhu, G. and Pot, I. and Brayer, G. D. and Withers, S. G. and McIntosh, L. P.}
}
@article {4971,
	title = {Hyperfine structure in the rotational spectrum of GaF: A comparison of experimental and calculated spin-rotation and electric field gradient tensors},
	journal = {Journal of Molecular Spectroscopy},
	volume = {204},
	number = {2},
	year = {2000},
	note = {ISI Document Delivery No.: 380JBTimes Cited: 18Cited Reference Count: 74},
	month = {Dec},
	pages = {184-194},
	type = {Article},
	abstract = {{The high-resolution pure rotational spectrum of Gal; has been measured using a Balle-Flygare-type Fourier transform spectrometer. improved nuclear quadrupolar coupling constants and rotational constants have been obtained along with the first reported fluorine spin-rotation constant for gallium fluoride, C-I ((GaF)-Ga-69-F-19},
	keywords = {ab initio calculations, CHEMICAL-SHIFTS, CONSTANTS, electric field gradient tensors, FINITE BASIS-SET, gallium fluoride, group-13 fluorides, HARTREE-FOCK CALCULATIONS, hyperfine structure, LASER-ABLATION, MICROWAVE-SPECTRUM, MILLIMETER, MOLECULES, MONOFLUORIDE, NMR, nuclear magnetic shielding tensors, quadrupolar coupling, QUADRUPOLE COUPLING-CONSTANTS, rotational spectroscopy, SPECTROSCOPY, spin-rotation constants},
	isbn = {0022-2852},
	url = {<Go to ISI>://000165697100003},
	author = {Wasylishen, R. E. and Bryce, D. L. and Evans, C. J. and Gerry, M. C. L.}
}
@article {4815,
	title = {Investigation of the viability of solid-state NMR distance determinations in multiple spin systems of unknown structure},
	journal = {Journal of Physical Chemistry B},
	volume = {104},
	number = {1},
	year = {2000},
	note = {ISI Document Delivery No.: 283BJTimes Cited: 26Cited Reference Count: 37},
	month = {Jan},
	pages = {48-55},
	type = {Article},
	abstract = {This paper presents theoretical rotational-echo double-resonance (REDOR) and transferred-echo double-resonance (TEDOR) curves calculated for several three-spin systems and explores the potential for determining reliable distances in multiple-spin systems of unknown geometry. These NMR techniques can provide distances which compare very well with those obtained by X-ray diffraction if the samples contain isolated heteronuclear (IS) spin pairs and are currently being used in structural investigations of solids including peptides, polymers, and inorganic materials. The situation is less clear when small clusters of spins (e.g., INS systems) are present, and although the multispin dephasing can be calculated, very few examples have been reported in the literature. In most cases the spin system geometry was known before analysis of the NMR data, thus it is unclear whether reliable distances can be determined when the geometry of the spin system is completely unknown. To investigate the uniqueness of distance determinations from fitting of multispin REDOR and TEDOR data, the theoretical dephasing was calculated for a selection of I2S systems. The effects of varying the two I-S dipolar couplings and the I-A-S-I-B angle, zeta, were studied. The full range of zeta (0 degrees less than or equal to zeta less than or equal to 180 degrees) was considered, and the magnitudes of the dipolar couplings selected are typical of couplings expected for commonly studied nuclei. A variation of 10 degrees or more is required to effect a noticeable change and the dephasing is identical for zeta and 180 degrees - zeta. The most distinctive behavior is observed when zeta is small (or close to 180 degrees), otherwise there are quite minor differences. Spin systems with quite different geometries may exhibit very similar dephasing, and in some cases the curves are identical to those for an isolated IS spin pair. These calculations indicate that it is highly unlikely that reliable distances can be obtained directly from REDOR and TEDOR experiments on multiple spin systems when the number of spins and their geometrical arrangement is completely unknown. Furthermore, it is possible to obtain incorrect distances if isolated spin pairs are assumed and multiple spins are present.},
	keywords = {COMPLEX, DOUBLE-RESONANCE NMR, ECHO DOUBLE-RESONANCE, NMR, NUCLEI, QUADRUPOLAR, REDOR, ROTATIONAL-ECHO, zeolites},
	isbn = {1089-5647},
	url = {<Go to ISI>://000085256000007},
	author = {Fyfe, C. A. and Lewis, A. R.}
}
@article {4746,
	title = {Monte Carlo simulations of zero electric field gradient liquid crystal mixtures},
	journal = {Chemical Physics Letters},
	volume = {331},
	number = {5-6},
	year = {2000},
	note = {ISI Document Delivery No.: 382YCTimes Cited: 13Cited Reference Count: 14},
	month = {Dec},
	pages = {455-464},
	type = {Article},
	abstract = {We explore with Monte Carlo simulations the NMR finding that solutes in special nematic liquid crystal mixtures {\textquoteright}feel{\textquoteright} zero average electric field gradient F-ZZ. The simulations involve solute-solvent mixtures of 1000 identical Gay-Berne ellipsoidal particles with added electric quadrupoles of varying strengths placed at particle centres. As long as all quadrupoles are sufficiently small, F-ZZ calculated at the particle centres is equal for all particles. For larger quadrupole moments, interactions among quadrupoles alter the interparticle distribution and subsequently F-ZZ depends on both solvent and solute quadrupoles; in general, the quadrupolar interactions produce a negative contribution to energy. (C) 2000 Elsevier Science B.V. All rights reserved.},
	keywords = {NMR, orientational order, SHAPE, SOLUTES},
	isbn = {0009-2614},
	url = {<Go to ISI>://000165854100016},
	author = {Burnell, E. E. and Berardi, R. and Syvitski, R. T. and Zannoni, C.}
}
@article {4954,
	title = {Nuclear magnetic resonance studies of helical dipyrromethene-zinc complexes},
	journal = {Organic Letters},
	volume = {2},
	number = {9},
	year = {2000},
	note = {ISI Document Delivery No.: 309XRTimes Cited: 27Cited Reference Count: 16},
	month = {May},
	pages = {1315-1318},
	type = {Article},
	abstract = {Analysis of helical chirality within dinuclear dipyrromethene-Zn(II) complexes has been achieved with the use of H-1 NMR spectroscopy. The use of AgFOD and chiral lanthanide shift reagents gives fully resolved resonances attributable to two diastereomeric helical complexes.},
	keywords = {chirality, LIGANDS, NMR, RESOLUTION, SHIFT-REAGENTS},
	isbn = {1523-7060},
	url = {<Go to ISI>://000086795200036},
	author = {Thompson, A. and Dolphin, D.}
}
@article {4523,
	title = {Can global target analysis of the splitting and spin relaxation from a ring-deuterated mesogen produce dynamical information?},
	journal = {Molecular Crystals and Liquid Crystals Science and Technology Section a-Molecular Crystals and Liquid Crystals},
	volume = {331},
	year = {1999},
	note = {ISI Document Delivery No.: 241JCTimes Cited: 0Cited Reference Count: 2017th International Liquid Crystal ConferenceJUL 19-24, 1998STRASBOURG, FRANCECaisse Epargne, CNRS, Conseil Gen Bas Rhin, France Telecom, Gordon \& Breach Publishing Grp, Instec Inc, Inst Phys Chimie Materiaux Strasbourg, Reg ALSACE, Rolic Liquid Crystals R\&D Co, STOE \& CIE GmbH, Univ Louis Pasteur, Ville Strasbourg, Int Liquid Crystal Soc, Ecole Chimie, Polymeres Materiaux Strasbourg, Lab Fluides Complexex, Inst Charles SadronPart 4},
	pages = {2003-2013},
	type = {Proceedings Paper},
	abstract = {We report on the measurements of quadrupolar splitting and spectral densities of motion for the phenylthio ring deuterons as a function of temperature in 4-pentylphenylthio-4{\textquoteright}-octyloxy- benzoate ((8) over bar S5 - d(4)). A global analysis of all these observables at 9 different temperatures in the nematic and smectic A phases is shown to give useful information on the core dynamics of (8) over bar S5. Inclusion of the smectic C phase in the global analysis is possible; but gives a poorer overall fitting quality factor.},
	keywords = {deuteron spin relaxation, LIQUID-CRYSTAL PHASES, MOLECULAR ORDER, MOTIONS, NMR, RESONANCE, ROTATIONAL DIFFUSION, smectogen},
	isbn = {1058-725X},
	url = {<Go to ISI>://000082878400020},
	author = {Dong, R. Y. and Bates, G. S. and Shen, X.}
}
@article {4578,
	title = {The cellulose-binding domains from Cellulomonas fimi beta-1,4-glucanase CenC bind nitroxide spin-labeled cellooligosaccharides in multiple orientations},
	journal = {Journal of Molecular Biology},
	volume = {287},
	number = {3},
	year = {1999},
	note = {ISI Document Delivery No.: 184RGTimes Cited: 38Cited Reference Count: 46},
	month = {Apr},
	pages = {609-625},
	type = {Article},
	abstract = {The N-terminal cellulose-binding domains CBDN1 and CBDN2 from Cellulomonas fimi cellulase CenC each adopt a jelly-roll beta-sandwich structure with a cleft into which amorphous cellulose and soluble cellooligosaccharides bind. To determine the orientation of the sugar chain within these binding clefts, the association of TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl-4-yl) spin-labeled derivatives of cellotriose and cellotetraose with isolated CBDN1 and CBDN2 was studied using heteronuclear H-1-N-15 NMR spectroscopy. Quantitative binding measurements indicate that the TEMPO moiety does not significantly perturb the affinity of the cellooligo-saccharide derivatives for the CBDs. The paramagnetic enhancements of the amide H-1(N) longitudinal (Delta R-1) and transverse (Delta R-2) relaxation rates were measured by comparing the effects of TEMPO-cellotetraose in its nitroxide (oxidized) and hydroxylamine (reduced) forms on the two CBDs. The bound spin-label affects most significantly the relaxation rates of amides located at both ends of the sugar-binding cleft of each CBD. Similar results are observed with TEMPO-cellotriose bound to CBDN1. This demonstrates that the TEMPO-labeled cellooligosaccharides, and by inference strands of amorphous cellulose, can associate with CBDN1 and CBDN2 in either orientation across their beta-sheet binding clefts. The ratio of the association constants for binding in each of these two orientations is estimated to be within a factor of five to tenfold. This finding is consistent with the approximate symmetry of the hydrogen-bonding groups on both the cellooligosaccharides and the residues forming the binding clefts of the CenC CBDs. (C) 1999 Academic Press.},
	keywords = {CELLULASES, ENDOGLUCANASE, GLYCOSYNTHASE, MAGNETIC-RESONANCE SPECTROSCOPY, NMR, protein-carbohydrate interaction, PROTEINS, SENSITIVITY, SITE, SPECIFICITY, spin label},
	isbn = {0022-2836},
	url = {<Go to ISI>://000079626300013},
	author = {Johnson, P. E. and Brun, E. and Mackenzie, L. F. and Withers, S. G. and McIntosh, L. P.}
}
@article {4676,
	title = {NMR and molecular structure of partially oriented mono and para methyl- and chlorobenzenes dissolved in nematic liquid crystals},
	journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie},
	volume = {77},
	number = {11},
	year = {1999},
	note = {ISI Document Delivery No.: 253FETimes Cited: 8Cited Reference Count: 69},
	month = {Nov},
	pages = {1761-1774},
	type = {Article},
	abstract = {Spectral parameters, order parameters, and structural parameters, including the vibrationally corrected r(alpha) structure of the partially oriented solutes p-xylene, p-chlorotoluene, p-dichlorobenzene, toluene, and chlorobenzene dissolved in three liquid crystal mixtures, are reported. For samples containing the three solutes p-xylene, p-dichlorobenzene, and 1,3,5-trichlorobenzene, multiple quantum (MQ) nuclear magnetic resonance was used to aid in the analysis of the complex high-resolution spectra of the g-xylene. The high-resolution spectra of 1,3,5-trichlorobenzene and p-dichlorobenzene were easily identified and analyzed once the calculated p-xylene spectrum was subtracted from the experimental one. The methyl groups of p-xylene, p-chlorotoluene, and toluene have similar geometries when the structure is determined from dipolar couplings corrected for harmonic vibrations.},
	keywords = {ELECTRIC-DIPOLE INTERACTIONS, EXCITATION, H-2 NMR, MAGNETIC-RESONANCE, MEAN TORQUE, molecular structure, MULTIPLE-QUANTUM NMR, nematic liquid crystal, NMR, ORDER MATRIX, order parameter, SELECTIVE, SOLUTES, SOLVENTS, SPECTRA},
	isbn = {0008-4042},
	url = {<Go to ISI>://000083545300009},
	author = {Syvitski, R. T. and Burnell, E. E.}
}
@article {4616,
	title = {Vanadium complexes as insulin mimetic agents: Coordination chemistry and in vivo studies of oxovanadium(IV) and dioxovanadate(V) complexes formed from naturally occurring chelating oxazolinate, thiazolinate, or picolinate units},
	journal = {Inorganic Chemistry},
	volume = {38},
	number = {10},
	year = {1999},
	note = {ISI Document Delivery No.: 199BHTimes Cited: 72Cited Reference Count: 34},
	month = {May},
	pages = {2288-2293},
	type = {Article},
	abstract = {{The synthesis and characterization of four complexes containing naturally occurring binding groups are reported: VO(pic)(2). H2O (Hpic = picolinic or pyridine-2-carboxylic acid), NH4[VO2(pic)(2)]. 2H(2)O, VO(oz)(2) (Hoz = 2-(2{\textquoteright}- hydroxyphenyl)-2-oxazoline), and VO(thoz)(2) (Hthoz = 2-(2{\textquoteright}-hydroxyphenyl)-2-thiazoline). The X-ray structures of [NH4[VO2(pic)(2)]. 2H(2)O, VO(oz)(2), and VO(thoz)(2) have been determined. Crystals of NH4[VO2(pic)(2)]. 2H(2)O (C12H12N3O6V . 2H(2)O) are monoclinic, space group Cc, a 10.347(2) Angstrom},
	keywords = {BIS(MALTOLATO)OXOVANADIUM(IV), BMOV, CRYSTAL-STRUCTURE, DIABETIC RATS, GLUCOSE, NMR, SIDEROPHORE, SULFATE, SYSTEM, VANADATE},
	isbn = {0020-1669},
	url = {<Go to ISI>://000080459200009},
	author = {Melchior, M. and Thompson, K. H. and Jong, J. M. and Rettig, S. J. and Shuter, E. and Yuen, V. G. and Zhou, Y. and McNeill, J. H. and Orvig, Chris}
}
@article {4405,
	title = {Structure of the Ets-1 pointed domain and mitogen-activated protein kinase phosphorylation site},
	journal = {Proceedings of the National Academy of Sciences of the United States of America},
	volume = {95},
	number = {21},
	year = {1998},
	note = {ISI Document Delivery No.: 129DLTimes Cited: 84Cited Reference Count: 37},
	month = {Oct},
	pages = {12129-12134},
	type = {Article},
	abstract = {The Pointed (PNT) domain and an adjacent mitogen-activated protein (MAP) kinase phosphorylation site are defined by sequence conservation among a subset of ets transcription factors and are implicated in two regulatory strategies, protein interactions and posttranslational modifications, respectively. By using NMR, we have determined the structure of a 110-residue fragment of murine Ets-1 that includes the PNT domain and MAP kinase site. The Ets-1 PNT domain forms a monomeric five-helix bundle. The architecture is distinct from that of any known DNA- or protein-binding module, including the helix-loop-helix fold proposed for the PNT domain of the ets protein TEL. The MAP kinase site is in a highly flexible region of both the unphosphorylated and phosphorylated forms of the Ets-1 fragment. Phosphorylation alters neither the structure nor monomeric state of the PNT domain. These results suggest that the Ets-1 PNT domain functions in heterotypic protein interactions and support the possibility that target recognition is coupled to structuring of the MAP kinase site.},
	keywords = {beta, CHRONIC MYELOMONOCYTIC LEUKEMIA, FUSION, GENE, NMR, OLIGOMERIZATION, TEL, TRANSCRIPTION FACTORS, TRANSLOCATION, TROPONIN-C},
	isbn = {0027-8424},
	url = {<Go to ISI>://000076447900013},
	author = {Slupsky, C. M. and Gentile, L. N. and Donaldson, L. W. and Mackereth, C. D. and Seidel, J. J. and Graves, B. J. and McIntosh, L. P.}
}
@article {3926,
	title = {Cationic lanthanide complexes of N,N{\textquoteright}-bis(2-pyridylmethyl)ethylenediamine-N,N{\textquoteright}-diacetic acid (H(2)bped)},
	journal = {Inorganic Chemistry},
	volume = {36},
	number = {7},
	year = {1997},
	note = {ISI Document Delivery No.: WQ490Times Cited: 22Cited Reference Count: 51},
	month = {Mar},
	pages = {1316-1321},
	type = {Article},
	abstract = {A series of monocationic lanthanide complexes containing the ligand N,N{\textquoteright}-bis(2-pyridylmethyl)ethylenediamine-N,N{\textquoteright}-diacetate(2-) (bped(2-)) have been prepared and isolated as either the hexafluorophosphate or perchlorate salts. The complexes have been characterized by H-1 and C-13 NMR, +LSIMS, IR, and elemental analysis. Complex formation constants have been measured in water at 25 degrees C (mu = 0.16 M (NaCl)). log K (Ln(bped)](+)) (log K([Ln(bped)(OH)])): Ln = La, 10.81 (0.06); Ln = Nd, 11.99 (1.45); Ln = Gd, 12.37 (2.10); Ln = Ho, 12.31 (3.00); Ln = Yb, 13.32 (4.43). The stability constants for [M(bped)](+) increase from La(III) to Nd(III), plateau to Ho(III), and increase again to Yb(III), while the formation constants for [Ln(bped)(OH)] increase almost linearly with atomic number. The solution structures of the [Ln(bped)](+) complexes have been probed by multinuclear NMR (H-1, C-13, O-17) studies, and these indicate only one isomer present in solution; this isomer has 2-fold symmetry and is rigid at 20 degrees C on the NMR time scale. O-17 NMR studies of the paramagnetic lanthanides indicate that the hydration number is 3, [Ln(bped)(H2O)(2)](+), and that an overall coordination number of 9 is maintained across the lanthanide series.},
	keywords = {AQUEOUS-SOLUTION, CARBOXYLATES, COMPLEXES, COORDINATION-NUMBER, EDTA, GADOLINIUM(III), NMR, NUCLEAR MAGNETIC-RESONANCE, polarization, SHIFT-REAGENTS, SHIFTS, WATER-MOLECULES},
	isbn = {0020-1669},
	url = {<Go to ISI>://A1997WQ49000007},
	author = {Caravan, P. and Mehrkhodavandi, Parisa and Orvig, Chris}
}
@article {3926,
	title = {Cationic lanthanide complexes of N,N{\textquoteright}-bis(2-pyridylmethyl)ethylenediamine-N,N{\textquoteright}-diacetic acid (H(2)bped)},
	journal = {Inorganic Chemistry},
	volume = {36},
	number = {7},
	year = {1997},
	note = {ISI Document Delivery No.: WQ490Times Cited: 22Cited Reference Count: 51},
	month = {Mar},
	pages = {1316-1321},
	type = {Article},
	abstract = {A series of monocationic lanthanide complexes containing the ligand N,N{\textquoteright}-bis(2-pyridylmethyl)ethylenediamine-N,N{\textquoteright}-diacetate(2-) (bped(2-)) have been prepared and isolated as either the hexafluorophosphate or perchlorate salts. The complexes have been characterized by H-1 and C-13 NMR, +LSIMS, IR, and elemental analysis. Complex formation constants have been measured in water at 25 degrees C (mu = 0.16 M (NaCl)). log K (Ln(bped)](+)) (log K([Ln(bped)(OH)])): Ln = La, 10.81 (0.06); Ln = Nd, 11.99 (1.45); Ln = Gd, 12.37 (2.10); Ln = Ho, 12.31 (3.00); Ln = Yb, 13.32 (4.43). The stability constants for [M(bped)](+) increase from La(III) to Nd(III), plateau to Ho(III), and increase again to Yb(III), while the formation constants for [Ln(bped)(OH)] increase almost linearly with atomic number. The solution structures of the [Ln(bped)](+) complexes have been probed by multinuclear NMR (H-1, C-13, O-17) studies, and these indicate only one isomer present in solution; this isomer has 2-fold symmetry and is rigid at 20 degrees C on the NMR time scale. O-17 NMR studies of the paramagnetic lanthanides indicate that the hydration number is 3, [Ln(bped)(H2O)(2)](+), and that an overall coordination number of 9 is maintained across the lanthanide series.},
	keywords = {AQUEOUS-SOLUTION, CARBOXYLATES, COMPLEXES, COORDINATION-NUMBER, EDTA, GADOLINIUM(III), NMR, NUCLEAR MAGNETIC-RESONANCE, polarization, SHIFT-REAGENTS, SHIFTS, WATER-MOLECULES},
	isbn = {0020-1669},
	url = {<Go to ISI>://A1997WQ49000007},
	author = {Caravan, P. and Mehrkhodavandi, Parisa and Orvig, Chris}
}
@article {4020,
	title = {Complete measurement of the pK(a) values of the carboxyl and imidazole groups in Bacillus circulans xylanase},
	journal = {Protein Science},
	volume = {6},
	number = {12},
	year = {1997},
	note = {ISI Document Delivery No.: YK912Times Cited: 44Cited Reference Count: 29},
	month = {Dec},
	pages = {2667-2670},
	type = {Article},
	abstract = {Electrostatic interactions in proteins can be dissected experimentally by determining the pK(a), values of their constituent ionizable amino acids. To complement previous studies of the glutamic acid and histidine residues in Bacillus circulans xylanase (BCX), we have used NMR methods to measure the pK(a)s of the seven aspartic acids and the C-terminus of this protein. The pK(a)s of these carboxyls are all less than the corresponding values observed with random coil polypeptides, indicating that their ionization contributes favorably to the stability of the folded enzyme. In general, the aspartic acids with the most reduced pK(a)s are those with limited exposure to the solvent and a high degree of conservation among homologous xylanases. Most dramatically, Asp 53 and Asp 101 have pK(a)s < 2 and thus remain deprotonated in native BCX under all conditions examined. Asp 83 is completely buried, forming a strong salt bridge with Arg 136. In contrast, Asp 101 is located on the surface of the protein, stabilized in the deprotonated form by an extensive network of hydrogen bonds involving an internal water molecule and the neutral side-chain and main-chain atoms of Ser 100 and Thr 145. These data provide a complete experimental database for theoretical studies of the ionization behavior of BCX under acidic conditions.},
	keywords = {aspartic acid, electrostatics, FAMILIES, NMR, NMR ASSIGNMENTS, NUCLEAR-MAGNETIC-RESONANCE, PK(A), PROTEINS, RESIDUES, SHIFTS, titration, XYLANASE},
	isbn = {0961-8368},
	url = {<Go to ISI>://A1997YK91200024},
	author = {Joshi, M. D. and Hedberg, A. and McIntosh, L. P.}
}
@article {3938,
	title = {The effect of organotin compounds on the permeability of model biological membranes},
	journal = {Applied Organometallic Chemistry},
	volume = {11},
	number = {5},
	year = {1997},
	note = {ISI Document Delivery No.: WZ733Times Cited: 7Cited Reference Count: 28Pacifichem 95 Meeting on Safety and Environmental Effects of Organometallics1995HONOLULU, HI},
	month = {May},
	pages = {369-379},
	type = {Proceedings Paper},
	abstract = {The efflux of dimethylarsinic acid (DMA) from liposomes formed from egg phosphatidylcholine (EPC) is increased when tributyltin chloride (TBT) is added to the extraliposomal compartment; however the addition of monobutyltin trichloride (MBT) slows down the efflux. When the liposomes are prepared from EPC and organotin compounds, different mechanisms for DMA efflux seem to operate: TBT-EPC liposomes show a mixture of facilitated and passive diffusion; MBT-EPC liposomes show only passive diffusion. The facilitated diffusion of DMA(-) seems to be stopped by the addition of TBT to the extraliposomal compartment. (C) 1997 by John Wiley \& Sons, Ltd.},
	keywords = {bilayer, DIMETHYLARSINIC ACID, efflux, egg, ERYTHROCYTE, EXCHANGE, facilitated diffusion, LIPOSOMES, membrane modification, monobutyltin, NMR, PHOSPHATIDYLCHOLINE, tributyltin chloride, trichloride},
	isbn = {0268-2605},
	url = {<Go to ISI>://A1997WZ73300003},
	author = {Cullen, W. R. and Herring, F. G. and Nwata, B. U.}
}
@article {4107,
	title = {Monte Carlo simulations of solute ordering in nematic liquid crystals: Shape anisotropy and quadrupole-quadrupole interactions as orienting mechanisms},
	journal = {Physical Review E},
	volume = {55},
	number = {4},
	year = {1997},
	note = {ISI Document Delivery No.: WV249Times Cited: 17Cited Reference Count: 51},
	month = {Apr},
	pages = {4321-4337},
	type = {Article},
	abstract = {Monte Carlo computer simulations were used to investigate the effects of shape anisotropy and electrostatic interactions as mechanisms for orientational ordering of solutes in nematic liquid crystals. The simulation results were analyzed in terms of two theories of solute ordering which derive mean-field orientational potentials from the intermolecular pair potential. In the calculations, solute and solvent molecular shapes were approximated by hard ellipsoids. Most simulations also incorporated the interaction between point quadrupole moments placed at the centers of the ellipsoids. In the hard-core systems, orientational order parameters and distribution functions were calculated for a collection of different solutes under a variety of conditions. A theory due to Terzis and Photinos [Mol. Phys. 83, 847 (1994)] was found to underestimate the effect of shape anisotropy on orientational ordering drastically. The introduction of an effective solvent packing fraction was unable to improve the predictive power of the theory significantly. The quadrupolar systems were used to investigate a mean-field model for solute ordering which considers an interaction between the solute molecular quadrupole moment with an average electric-field gradient. The simulations indicate that the electric-field gradient sampled by the solute is highly dependent on the properties of the solute, contrary to some experimental evidence. Further, the effects of the intermolecular quadrupolar interactions on orientational ordering and the electric-field gradient were analyzed using a mean-field potential derived here and based on the theory due to Emsley, Palke, and Shilstone [Liq. Cryst. 9, 649 (1991)]. This model was found to provide a qualitatively correct but quantitatively imprecise prediction of orientational ordering.},
	keywords = {acetylene, COMPUTER-SIMULATION, ELECTRIC-DIPOLE INTERACTIONS, HARD ELLIPSOIDS, MEAN TORQUE, MOLECULAR-HYDROGEN, NMR, orientational order, POTENTIALS, SOLVENTS},
	isbn = {1063-651X},
	url = {<Go to ISI>://A1997WV24900067},
	author = {Polson, J. M. and Burnell, E. E.}
}
@article {4115,
	title = {Orientational order of 1,3-dichloro-2-ethenylbenzene in liquid crystal solvents},
	journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie},
	volume = {75},
	number = {8},
	year = {1997},
	note = {ISI Document Delivery No.: XX043Times Cited: 2Cited Reference Count: 38},
	month = {Aug},
	pages = {1156-1161},
	type = {Article},
	abstract = {The order parameter matrices of a molecule that has no symmetry, 1,3-dichloro-2-ethenylbenzene, dissolved in two different nematic liquid-crystal solvents are analyzed in terms of various models for the intermolecular mean-field potential. In a mixture of liquid crystals for which the interaction between the molecular quadrupole moment tensor and the average electric field gradient of the nematic solvent has been minimized, the orientational order is best described by models for the short-range anisotropic potential. The most successful potentials are written in terms of anisotropic interactions between the solute surface and the liquid-crystal mean field. This represents a strong test of such models because they simultaneously fit the five independent orientational parameters obtained from the same solute, thus removing the problems associated with comparing results among different solutes in either the same or a different sample tube.},
	keywords = {ALKYL CHAINS, ANISOTROPIC, FIELD, INTERMOLECULAR FORCES, liquid crystals, MAGNETIC-RESONANCE, MIXTURES, MOLECULES, NEMATIC SOLVENT, NMR, order parameters, PHASES, SHAPE, SOLUTES},
	isbn = {0008-4042},
	url = {<Go to ISI>://A1997XX04300014},
	author = {Rendell, J. C. T. and Zimmerman, D. S. and vanderEst, A. J. and Burnell, E. E.}
}
@article {4070,
	title = {Stereospecific assignment of the NH2 resonances from the primary amides of asparagine and glutamine side chains in isotopically labeled proteins},
	journal = {Journal of Biomolecular Nmr},
	volume = {9},
	number = {3},
	year = {1997},
	note = {ISI Document Delivery No.: XF937Times Cited: 18Cited Reference Count: 33},
	month = {Apr},
	pages = {306-312},
	type = {Article},
	abstract = {An HMQC-based pulse scheme is presented for the stereospecific assignment of asparagine and glutamine side-chain amide protons. The approach makes use of the recently developed quantitative-J correlation spectroscopy [Bar, A. et al. (1994) Methods Enzymol., 239, 79-105] to distinguish the E and Z primary amide protons and, as such, eliminates the need for assignments derived from more time-consuming and potentially ambiguous NOE methods. An application of this method to a uniformly N-15,C-13-labeled cellulose-binding domain is presented. When used in combination with a NOESY-HSQC experiment, the predominant chi(2) dihedral angles of two asparagine side chains in this protein can also be defined.},
	keywords = {ANGLE, BACKBONE AMIDE, C-13 MAGNETIZATION, dihedral, EXCITATION, H-1, HMQC spectroscopy, LARGER PROTEINS, N-15, NMR, primary amide, SATURATION, SPECTRA, SPECTROSCOPY, STEREOSPECIFIC ASSIGNMENT},
	isbn = {0925-2738},
	url = {<Go to ISI>://A1997XF93700008},
	author = {McIntosh, L. P. and Brun, E. and Kay, L. E.}
}
@article {3919,
	title = {Tritium nuclear magnetic resonance study of T-2, HT, and DT dissolved in nematic solvents},
	journal = {Physical Review E},
	volume = {55},
	number = {1},
	year = {1997},
	note = {ISI Document Delivery No.: WD545Times Cited: 5Cited Reference Count: 25Part A},
	month = {Jan},
	pages = {496-503},
	type = {Article},
	abstract = {A tritium nuclear magnetic resonance study is carried out on the T-2, HT, and DT isotopomers of dihydrogen dissolved in various nematic phases, including a zero-electric-field-gradient mixture. Ab initio calculations are performed to reproduce the observed dipolar couplings. Within the framework of the {\textquoteright}{\textquoteright}mean-field{\textquoteright}{\textquoteright} approximation, the results provide support for a picture in which two independent contributions to the solute orientation can be distinguished. One contribution involves a liquid-crystal-dependent interaction between the mean solvent electric-field gradient and the solute molecular quadrupole moment. The other contribution is of unknown origin; however, it is essentially identical in all liquid crystals and it can be modeled adequately with a phenomenological mean-field interaction. A remarkable feature of this second interaction is that it causes the average orientation of the asymmetrical isotopomers, and especially of HT, to behave differently from the symmetrical species.},
	keywords = {ELECTRIC-FIELD GRADIENTS, ENVIRONMENTS, LIQUID-CRYSTAL MIXTURES, MECHANISMS, METHANES, MOLECULAR-HYDROGEN, NMR, orientational order, SOLUTES},
	isbn = {1063-651X},
	url = {<Go to ISI>://A1997WD54500062},
	author = {Burnell, E. E. and de Lange, C. A. and Segre, A. L. and Capitani, D. and Angelini, G. and Lilla, G. and Barnhoorn, J. B. S.}
}
@article {3677,
	title = {Al-27/P-31 solid-state nmr structural investigations of AlPO4-5 molecular sieve},
	journal = {Zeolites},
	volume = {16},
	number = {1},
	year = {1996},
	note = {ISI Document Delivery No.: TM037Times Cited: 26Cited Reference Count: 16},
	month = {Jan},
	pages = {50-55},
	type = {Article},
	abstract = {Al-27/P-31 solid-state n.m.r. connectivity experiments were used to investigate the structure of the molecular sieve AlPO4-5 hydrated with D2O. Hydration with D2O resulted in an increased efficiency of coherence transfer from octahedral Al-27 to P-31 compared with hydration with H2O. The experiments prove directly that both the tetrahedral aluminum and the octahedral aluminum formed upon hydration are connected to phosphorus in the framework. The two-dimensional Al-27 {\textendash}> P-31 transferred-echo double-resonance and cross-polarization experiments show a downfield offset of the octahedral Al-27 correlation from the tetrahedral Al-27 correlation, consistent with the growth of a downfield shoulder on the P-31 resonance as water is incorporated into the lattice.},
	keywords = {Al-27/P-31 solid-state nmr connectivity experiments, AlPO4-5, FRAMEWORK, NMR, NUCLEI, octahedral aluminum, QUADRUPOLAR, VPI-5},
	isbn = {0144-2449},
	url = {<Go to ISI>://A1996TM03700009},
	author = {Fyfe, C. A. and Wongmoon, K. C. and Huang, Y.}
}
@article {3621,
	title = {Probing the role of tryptophan residues in a cellulose-binding domain by chemical modification},
	journal = {Protein Science},
	volume = {5},
	number = {11},
	year = {1996},
	note = {ISI Document Delivery No.: VQ786Times Cited: 41Cited Reference Count: 34},
	month = {Nov},
	pages = {2311-2318},
	type = {Article},
	abstract = {The cellulose-binding domain (CBDCex) of the mixed function glucanase-xylanase Cex from Cellulomonas fimi contains five tryptophans, two of which are located within the p-barrel structure and three exposed on the surface (Xu GY et al., 1995, Biochemistry 34:6993-7009). Although all five tryptophans can be oxidized by N-bromosuccinimide (NBS), stopped-flow measurements show that three tryptophans react faster than the other two. NMR analysis during the titration of CBDCex with NBS shows that the tryptophans on the surface of the protein are fully oxidized before there is significant reaction with the two buried tryptophans. Additionally, modification of the exposed tryptophans does not affect the conformation of the backbone of CBDCex, whereas complete oxidation of all five tryptophans denatures the polypeptide. The modification of the equivalent of one and two tryptophans by NBS reduces binding of CBDCex to cellulose by 70\% and 90\%, respectively. This confirms the direct role of the exposed aromatic residues in the binding of CBDCex to cellulose. Although adsorption to cellulose does afford some protection against NBS, as evidenced by the increased quantity of NBS required to oxidize all of the tryptophan residues, the polypeptide can still be oxidized completely when adsorbed. This suggests that, whereas the binding appears to be irreversible overall [Ong E et al., 1989, Bio/Technology 7:604-607], each of the exposed tryptophans interacts reversibly with cellulose.},
	keywords = {absorbance spectroscopy, ACTIVE-SITE, CELLOBIOHYDROLASE-I, cellulose-binding, ENDOGLUCANASE, ESCHERICHIA-COLI, FIMI, fluorescence spectroscopy, N-bromosuccinimide, NMR, NUCLEAR-MAGNETIC-RESONANCE, SCHIZOPHYLLUM-COMMUNE, SPECTROSCOPY, TRICHODERMA-REESEI, XYLANASE-A},
	isbn = {0961-8368},
	url = {<Go to ISI>://A1996VQ78600017},
	author = {Bray, M. R. and Johnson, P. E. and Gilkes, N. R. and McIntosh, L. P. and Kilburn, D. G. and Warren, R. A. J.}
}
@article {3800,
	title = {Secondary structure and NMR assignments of Bacillus circulans xylanase},
	journal = {Protein Science},
	volume = {5},
	number = {6},
	year = {1996},
	note = {ISI Document Delivery No.: UP617Times Cited: 23Cited Reference Count: 74},
	month = {Jun},
	pages = {1118-1135},
	type = {Article},
	abstract = {Bacillus circulans xylanase (BCX) is a member of the family of low molecular weight endo-beta-(1,4)-xylanases. The main-chain H-1, C-13, and N-15 resonances of this 20.4-kDa enzyme were assigned using heteronuclear NMR experiments recorded on a combination of selectively and uniformly labeled protein samples. Using chemical shift, NOE, J coupling, and amide hydrogen exchange information, 14 beta-strands, arranged in a network of three beta-sheets, and a single cy-helix were identified in BCX. The NMR-derived secondary structure and beta-sheet topology agree closely with that observed in the crystal structure of this protein. The H-N of Ile 118 has a strongly upfield-shifted resonance at 4.03 ppm, indicative of a potential amide-aromatic hydrogen bond to the indole ring of Trp 71. This interaction, which is conserved in all low molecular weight xylanases of known structure, may play an important role in establishing the active site conformation of these enzymes. Following hen egg white and bacteriophage T4 lysozymes, B. circulans xylanase represents the third family of beta-glycanases for which extensive NMR assignments have been reported. These assignments provide the background for detailed studies of the mechanism of carbohydrate recognition and hydrolysis by this bacterial xylanase.},
	keywords = {amide-aromatic hydrogen bond, AMINO-ACID, ASSIGNMENTS, BACKBONE AMIDE, beta-glycanase, C-13-LABELED PROTEINS, C-ALPHA, chemical shift index, CHEMICAL-SHIFTS, COUPLING-CONSTANTS, LARGER PROTEINS, NMR, NUCLEAR-MAGNETIC-RESONANCE, SECONDARY STRUCTURE, SIDE-CHAIN RESONANCES, SOLVENT, SUPPRESSION, XYLANASE},
	isbn = {0961-8368},
	url = {<Go to ISI>://A1996UP61700014},
	author = {Plesniak, L. A. and Wakarchuk, W. W. and McIntosh, L. P.}
}
@article {3819,
	title = {Structural coupling of the inhibitory regions flanking the ETS domain of murine Ets-1},
	journal = {Protein Science},
	volume = {5},
	number = {2},
	year = {1996},
	note = {ISI Document Delivery No.: TU724Times Cited: 46Cited Reference Count: 66},
	month = {Feb},
	pages = {296-309},
	type = {Article},
	abstract = {Several members of the ets gene family of transcription factors show negative regulation of DNA binding by intramolecular interactions. A structural mechanism for this auto-inhibition is investigated using a 161-residue N-terminal deletion mutant of murine Ets-1, Ets-1 Delta N280. This protein shows a similar reduced affinity for DNA as native Ets-1 because it contains the ETS domain in context of the flanking amino- and carboxy-terminal regions that together mediate repression of DNA binding. The secondary structure of Ets-1 Delta N280 was determined using NMR chemical shift, NOE, J coupling, and amide hydrogen exchange information. In addition to the winged helix-turn-helix ETS domain, Ets-1 Delta N280 contains two alpha-helices in the amino-terminal inhibitory region and one alpha-helix in the carboxy-terminal inhibitory region. Chemical shift comparisons were made between this protein and an activated form of Ets-1 lacking the amino-terminal inhibitory region. The spectral differences demonstrate that the amino- and carboxy-terminal inhibitory sequences are structurally coupled to one another, thus explaining the observation that both regions are required for the repression of DNA binding. Furthermore, these data show that the inhibitory sequences also interact directly with the first helix of the intervening ETS domain, thereby providing a pathway for the repression of DNA binding. These results lead to a model of an inhibitory module in Ets-1 composed of both the amino- and carboxy-terminal regions interfaced with the ETS domain. This establishes the structural framework for understanding the intramolecular inhibition of Ets-1 DNA binding.},
	keywords = {3-DIMENSIONAL NMR-SPECTROSCOPY, allosteric, ASSIGNMENT, CRYSTAL-STRUCTURE, DNA binding, DNA-BINDING MOTIF, ETS domain, Ets-1 and Ets-2, FACTORS, H-1, INHIBITION, INTRAMOLECULAR, LARGER PROTEINS, N-15 NMR, NMR, protein structure, SPECTRA, transcription, V-ETS, winged helix-turn-helix},
	isbn = {0961-8368},
	url = {<Go to ISI>://A1996TU72400014},
	author = {Skalicky, J. J. and Donaldson, L. W. and Petersen, J. M. and Graves, B. J. and McIntosh, L. P.}
}
@article {3339,
	title = {DIPOLAR-BASED AL-27-]SI-29 SOLID-STATE NMR CONNECTIVITY EXPERIMENTS IN ZEOLITE MOLECULAR-SIEVE FRAMEWORKS},
	journal = {Journal of Physical Chemistry},
	volume = {99},
	number = {21},
	year = {1995},
	note = {ISI Document Delivery No.: RA147Times Cited: 64Cited Reference Count: 38},
	month = {May},
	pages = {8707-8716},
	type = {Article},
	abstract = {In this work we present the results of a systematic investigation of a set of dipolar-based Al-27 {\textendash}> Si-29 connectivity experiments for a series: of representative zeolite molecular sieve frameworks: zeolites A, X, Y, and Omega. Coherence transfer from quadrupolar Al-27 (I = 5/2) to Si-29 (I = 1/2) nuclei through cross polarization and transferred-echo double-resonance (TEDOR) experiments is. observed, and an experimental investigation of the parameters controlling the efficiency of both experiments is presented. Rotational-echo double-resonance (REDOR) and dipolar-dephasing difference experiments are also demonstrated. These experiments utilize the heteronuclear dipolar couplings, whose magnitudes are proportional to the inverse third power of the internuclear distance and are therefore extremely sensitive to the separation of the coupled spins. In addition, we demonstrate that for these dipolar-based experiments, there is a relative enhancement of a given resonance which is approximately linear with the number of aluminum atoms in the neighboring tetrahedral sites. Two-dimensional extensions of the cross-polarization and TEDOR experiments are also possible and will be of use for complex mixtures or where several resonances are observable in the one-dimensional spectra of the two nuclei.},
	keywords = {ANGLE, CROSS-POLARIZATION, DOUBLE-ROTOR, ECHO DOUBLE-RESONANCE, INORGANIC SOLIDS, MAS-NMR, NMR, NUCLEAR MAGNETIC-RESONANCE, QUADRUPOLAR NUCLEI, SPECTROSCOPY, VPI-5},
	isbn = {0022-3654},
	url = {<Go to ISI>://A1995RA14700041},
	author = {Fyfe, C. A. and Wongmoon, K. C. and Huang, Y. and Grondey, H. and Mueller, K. T.}
}
@article {3227,
	title = {THE GENERATION OF UNUSUAL NOBLE-METAL CATIONS IN FLUORO ACIDS AND SUPER ACIDS, AND THEIR SPECTROSCOPIC PROPERTIES},
	journal = {Journal of Fluorine Chemistry},
	volume = {72},
	number = {2},
	year = {1995},
	note = {ISI Document Delivery No.: RD582Times Cited: 13Cited Reference Count: 39International Conference on Fluorine Chemistry 94 KyotoJUL 27-30, 1994KYOTO, JAPANJapan Soc Promot Sci, 155th Comm Fluorine Chem, Chem Soc Japan, Electrochem Soc Japan, Pharm Soc Japan, Soc Synth Organ Chem},
	month = {Jun},
	pages = {195-201},
	type = {Proceedings Paper},
	abstract = {{Two types of highly electrophilic cations, {\textquoteright}bare{\textquoteright} M(2+) or carbonyl cations, formed by the noble metals palladium and platinum (Group 10) and silver and gold (Group 11) in low oxidation states (+1 or +2) are generated in highly acidic media. The acidic media consists of: the Bronsted superacid HSO3F; the Lewis superacid SbF5; and the conjugate superacid HSO3F-SbF5. Derived from these superacids are the very weakly nucleophilic anions SO3F- or Sb2F11- as counterions to stabilize the cations in solids. Finally, stabilization of the highly electrophilic cations by coordination to CO leads to isolable complexes, unprecedented in transition-metal chemistry in their structural, spectroscopic and bonding characteristics. The cations discussed include, in addition to {\textquoteright}bare{\textquoteright} M(2+) (M=Ag or Au): linear [M(CO)(n)](+)},
	keywords = {CARBONYL, FLUORO ACIDS, FLUOROSULFATE DERIVATIVES, GOLD, IONS, IR spectroscopy, MOLECULAR-STRUCTURE, NMR, NOBLE-METAL CATIONS, PALLADIUM(II), SILVER(II), SPECTROSCOPY, SUPER ACIDS, UNDECAFLUORODIANTIMONATE(V), X-RAY CRYSTAL STRUCTURES},
	isbn = {0022-1139},
	url = {<Go to ISI>://A1995RD58200007},
	author = {Aubke, F.}
}
@inbook {3511,
	title = {Isomorphous substitution of silicon by boron or aluminum in layered silicates},
	booktitle = {Catalysis by Microporous Materials},
	series = {Studies in Surface Science and Catalysis},
	volume = {94},
	year = {1995},
	note = {ISI Document Delivery No.: BE31JTimes Cited: 7Cited Reference Count: 15Proceedings PaperInternational Symposium on Catalysis by Microporous Materials (ZEOCAT 95)JUL 09-13, 1995SZOMBATHELY, HUNGARYSARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS},
	pages = {47-54},
	publisher = {Elsevier Science Publ B V},
	organization = {Elsevier Science Publ B V},
	address = {Amsterdam},
	abstract = {In order to systematically change the properties of layered silicate materials, we have investigated the possibility of isomorphous substitution of silicon by aluminum or boron. It is demonstrated that addition of boron and/or aluminum compounds to the reaction mixture leads directly to boron and aluminum containing layered materials in a hydrothermal crystallization process without further treatment. The layered materials obtained were identified as hectorite types, magadiite and kenyaite-like types. The isomorphous substitutions were pr-oven by B-11, Al-27, and Si-29 solid state MMR spectroscopy.},
	keywords = {MAGADIITE, NMR, SODIUM, STATE},
	isbn = {0-444-82049-3},
	url = {<Go to ISI>://A1995BE31J00005},
	author = {Schwieger, W. and Pohl, K. and Brenn, U. and Fyfe, C. A. and Grondey, H. and Fu, G. and Kokotailo, G. T.},
	editor = {Beyer, H. K. and Karge, H. G. and Kiricsi, I. and Nagy, J. B.}
}
@article {3230,
	title = {THE N-15-ISOTOPOMERS OF CIS-DIFLUORODIAZINE AND TRANS-DIFLUORODIAZINE - A F-19 NMR INVESTIGATION OF THE 2 [AX](2), SPIN SYSTEMS OF (N2F2)-N-15},
	journal = {Magnetic Resonance in Chemistry},
	volume = {33},
	number = {10},
	year = {1995},
	note = {ISI Document Delivery No.: RY962Times Cited: 3Cited Reference Count: 24},
	month = {Oct},
	pages = {817-822},
	type = {Article},
	abstract = {The decomposition of (N3P)-N-15 at - 20 degrees C leads to cis- and trans-(N2F2)-N-15. The corresponding F-19 NMR spectra were analysed as [AX](2) systems. F-19, N-15 and N-14 NMR spectra were simulated using the novel PC program systems DSYMPCD, DCYMPCD and WIN-DAISY running under WIN-NMR. Stereospecific coupling constants were obtained for both isomers. Comparison of the F-19 NMR spectra from both the [(1/2)A(1/2)X](2) and the[(1)A(1/2)X](2) systems in (N2F2)-N-15 and (N2F2)-N-14 overcomes the inherent ambiguities of the [AX](2) analysis.},
	keywords = {DCYMPCD, DSYMPCD, F-19, N-14, N-15, N2F2, NMR, WIN-DAISY},
	isbn = {0749-1581},
	url = {<Go to ISI>://A1995RY96200008},
	author = {Aubke, F. and Hagele, G. and Willner, H.}
}
@article {3337,
	title = {STRUCTURAL INVESTIGATIONS OF SAPO-37 MOLECULAR-SIEVE BY COHERENCE-TRANSFER AND DIPOLAR-DEPHASING SOLID-STATE NUCLEAR-MAGNETIC-RESONANCE EXPERIMENTS},
	journal = {Microporous Materials},
	volume = {5},
	number = {1-2},
	year = {1995},
	note = {ISI Document Delivery No.: TD675Times Cited: 16Cited Reference Count: 21},
	month = {Oct},
	pages = {29-37},
	type = {Article},
	abstract = {In this work, dipolar-based coherence-transfer and dipolar-dephasing solid-state nuclear magnetic resonance (NMR) experiments were performed to investigate the structure of the silicoaluminophosphate molecular sieve SAPO-37. The Al-27,Si-29 transferred-echo double-resonance (TEDOR) experiment directly proves, for the first time, that silicon substitutes for phosphorus atoms in the framework via the SM2 mechanism. The Al-27 (P-31) and Al-27 (Si-29) dipolar-dephasing difference experiments and the two-dimensional Al-27{\textendash}>P-31 TEDOR experiment indicate the presence of three types of aluminum environments: tetrahedral Al surrounded by symmetrical [4P] or [4Si] environments which give rise to a sharp resonance, tetrahedral Al surrounded by asymmetrical [3P, Si], [2P, 2Si] or [P, 3Si] environments which give rise to a broad resonance, and also extra-framework amorphous octahedral Al.},
	keywords = {AL-27, COHERENCE-TRANSFER, DIPOLAR-DEPHASING, NMR, QUADRUPOLAR, SAPO-37 MOLECULAR SIEVE, SILICOALUMINOPHOSPHATE, TRANSFERRED-ECHO DOUBLE-RESONANCE, VPI-5},
	isbn = {0927-6513},
	url = {<Go to ISI>://A1995TD67500004},
	author = {Fyfe, C. A. and Wongmoon, K. C. and Huang, Y. and Grondey, H.}
}
@inbook {3163,
	title = {MUON SPIN RELAXATION STUDIES OF CYCLOHEXADIENYL RADICALS IN NAUSY},
	booktitle = {Zeolites and Related Microporous Materials: State of the Art 1994},
	series = {Studies in Surface Science and Catalysis},
	volume = {84},
	year = {1994},
	note = {ISI Document Delivery No.: BD02ETimes Cited: 3Cited Reference Count: 22Proceedings Paper10th International Zeolite ConferenceJUL 17-22, 1994GARMISCH PARTENKIR, GERMANYSARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS},
	pages = {469-475},
	publisher = {Elsevier Science Publ B V},
	organization = {Elsevier Science Publ B V},
	address = {Amsterdam},
	abstract = {The avoided level crossing muon spin resonance (ALC-mu SR) technique is a promising new tool that can be used as a highly sensitive microscopic probe of radical motions in zeolites. We report a recent experiment in which this technique was used to identify a muonated cyclohexadienyl radical (C(6)H(6)Mu) and explore its reorientational dynamics in NaUSY. The observed evolution of the Delta M=1 ALC resonance lines are interpreted in terms of the site exchange dynamics of the radical.},
	keywords = {benzene, DIFFUSION, LEVEL-CROSSING RESONANCE, LOCALIZATION, MOLECULAR-DYNAMICS, NAX, NMR, NUCLEAR MAGNETIC-RESONANCE, SODIUM-Y ZEOLITE},
	isbn = {0-444-81847-2},
	url = {<Go to ISI>://A1994BD02E00057},
	author = {Shelley, M. and Arseneau, D. J. and Senba, M. and Pan, J. J. and Snooks, R. and Kreitzman, S. R. and Fleming, Donald G. and Roduner, E.},
	editor = {Weitkamp, J. and Karge, H. G. and Pfeifer, H. and Holderich, W.}
}
@article {3038,
	title = {NUCLEAR-MAGNETIC-RESONANCE IMAGING AS A PROBE OF THE FREEZING-THAWING PHENOMENA OF LIQUIDS IN HETEROGENEOUS SYSTEMS},
	journal = {Magnetic Resonance in Chemistry},
	volume = {32},
	number = {5},
	year = {1994},
	note = {ISI Document Delivery No.: NK844Times Cited: 2Cited Reference Count: 18},
	month = {May},
	pages = {276-283},
	type = {Article},
	abstract = {NMR microscopic imaging is shown to be an excellent probe of the freezing and thawing phenomena of liquids in heterogeneous chemical systems, and, in addition, is capable of monitoring the freezing-thawing of mixed solvent systems. In the model mixed solvent system Me(2)SO-water, the chemical shift specific slice selective (C4S) imaging technique is used to obtain the spatial distributions of the concentrations and mobilities of the two individual solvents in test samples. Measurements of relaxation parameters make it possible to choose values of imaging parameters TE and TR to ensure quantitative reliability of the images. Images of test samples generated at various temperatures demonstrate the qualitative relationship between image intensity and the Me(2)SO-water phase diagram. This series of experiments verifies that NMR microscopic imaging will be a powerful tool for the study of liquids within solid matrices, and in particular of cryoprotectant solvents in biological systems.},
	keywords = {CRYOPROTECTANT, DIMETHYLSULFOXIDE, FREEZING, NMR, NMR imaging, RESOLUTION},
	isbn = {0749-1581},
	url = {<Go to ISI>://A1994NK84400003},
	author = {Fyfe, C. A. and Isbell, S. A. and Burlinson, N. E.}
}
@article {2860,
	title = {ORIENTATIONAL ORDER OF PLANAR SOLUTES IN A ZERO AVERAGE ELECTRIC-FIELD GRADIENT NEMATIC ENVIRONMENT},
	journal = {Molecular Physics},
	volume = {78},
	number = {3},
	year = {1993},
	note = {ISI Document Delivery No.: KQ355Times Cited: 6Cited Reference Count: 31},
	month = {Feb},
	pages = {673-685},
	type = {Article},
	abstract = {The order matrices for 19 dihalobenzenes of C(s) and C2v symmetry have been measured using the NMR spectra of these molecules as solutes in the nematic mixture of 55 wt\% Merck ZLI-1132 and 45 wt\% N-(4-ethoxybenzylidene)-2,6-dideutero-4{\textquoteright}-n-butylaniline. In this liquid crystal, the contribution to the orientational potential from the interaction between the molecular quadrupole moment and the mean electric field gradient of the liquid crystal can be neglected. The results are compared with predictions of a model which describes the anisotropic intermolecular potential in terms of (1) an elastic distortion of the liquid crystal and (2) an anisotropic surface interaction between solute and liquid crystal. Not only are the largest (in magnitude) order parameters very well fitted, but also the calculated anisotropies in the order matrices agree with the experimental ones. It is demonstrated that the results cannot be fitted with a bond-additive approach.},
	keywords = {HYDROGEN, LIQUID-CRYSTALS, NMR, SIZE},
	isbn = {0026-8976},
	url = {<Go to ISI>://A1993KQ35500010},
	author = {Li, K. Y. Z. and Zimmerman, D. S. and Burnell, E. E.}
}
@article {2847,
	title = {POLYMASTIAMIDE-A, A NOVEL STEROID AMINO-ACID CONJUGATE ISOLATED FROM THE NORWEGIAN MARINE SPONGE POLYMASTIA-BOLETIFORMIS (LAMARCK, 1815)},
	journal = {Journal of Organic Chemistry},
	volume = {58},
	number = {24},
	year = {1993},
	note = {ISI Document Delivery No.: MJ868Times Cited: 22Cited Reference Count: 13},
	month = {Nov},
	pages = {6924-6927},
	type = {Note},
	keywords = {NMR},
	isbn = {0022-3263},
	url = {<Go to ISI>://A1993MJ86800073},
	author = {Kong, F. M. and Andersen, R. J.}
}
@article {2881,
	title = {SYNTHESIS OF ISOTOPICALLY LABELED MONOMERS AND POLYMERS OF 4-HYDROXYBENZOIC ACID AND 6-HYDROXY-2-NAPHTHOIC ACID},
	journal = {Makromolekulare Chemie-Macromolecular Chemistry and Physics},
	volume = {194},
	number = {2},
	year = {1993},
	note = {ISI Document Delivery No.: KM057Times Cited: 5Cited Reference Count: 36},
	month = {Feb},
	pages = {649-663},
	type = {Article},
	abstract = {Synthesis and characterization of 4-acetoxybenzoic acid and 6-acetoxy-2-naphthoic acid, labelled with deuterium in the rings and with carbon-13 and oxygen-17 in the carboxyl-positions, and of the corresponding homo- and copolyesters, are described. Kinetic studies of high-temperature deuteration were performed on 6-hydroxy-2-naphthoic acid. Mass spectrometry provides information about the degree of labelling with H-2, C-13 and O-17. Composition and molecular weight of isotopically labelled polymers were monitored by H-1 NMR after digestion in basic methanol. The thermal behavior was investigated by differential scanning calorimetry and thermogravimetry.},
	keywords = {COPOLYESTERS, HYDROXYBENZOIC ACID, NMR, TRANSITIONS},
	isbn = {0025-116X},
	url = {<Go to ISI>://A1993KM05700024},
	author = {Niessner, N. and Muhlebach, A. and Lyerla, J. R. and Facey, G. A. and Fyfe, C. A.}
}
@article {2714,
	title = {ZERO ELECTRIC-FIELD GRADIENT MIXTURES FOR THE ELUCIDATION OF ORIENTATIONAL MECHANISMS},
	journal = {Liquid Crystals},
	volume = {13},
	number = {3},
	year = {1993},
	note = {ISI Document Delivery No.: KX191Times Cited: 22Cited Reference Count: 28},
	month = {Mar},
	pages = {319-343},
	type = {Article},
	abstract = {A novel zero electric field gradient nematic liquid crystal made up from two nematic liquid crystal components is employed as a solvent for a series of molecules ranging from small molecules to mesogens themselves. Nuclear magnetic resonance is used to determine the degree of order of the solute and solvent molecules. Results are compared to those obtained for two completely different zero electric field gradient nematic mixtures. The comparison strongly indicates that for a variety of molecules largely differing in size, shape and flexibility their degree of order can be described by a single orientation mechanism. This mechanism can be adequately modelled by a simple phenomenological mean field model based on the size and shape anisotropy of the dissolved species. The use of zero electric field gradient mixtures in combination with this mean field model allows the prediction of solute order parameters at approximately the 10 per cent level.},
	keywords = {ANISOTROPIC ENVIRONMENTS, METHANES, MOLECULES, NEMATIC LIQUID-CRYSTALS, NMR, ORDER, SIZE, SOLUTES, SOLVENTS},
	isbn = {0267-8292},
	url = {<Go to ISI>://A1993KX19100001},
	author = {Barnhoorn, J. B. S. and de Lange, C. A. and Burnell, E. E.}
}
@article {7379,
	title = {TRITERPENE CONSTITUENTS OF THE DWARF BIRCH, BETULA-GLANDULOSA},
	journal = {Phytochemistry},
	volume = {31},
	number = {7},
	year = {1992},
	note = {ISI Document Delivery No.: JC920Times Cited: 11Cited Reference Count: 12},
	month = {Jul},
	pages = {2321-2324},
	type = {Article},
	abstract = {Juvenile stages of the dwarf birch, Betula glandulosa, from the Yukon, Canada, are rarely browsed by snowshoe hares (LePus americanus). Chemical investigation of extracts of B. glandulosa which strongly deter browsing by snowshoe hares has led to the isolation and structure determination of the new metabolite, deacetoxypapyriferic acid. Dammar-24-ene-12-beta-O-acetyl-20(S)-ol-3-one, a previously unknown natural product, was obtained from extracts which did not deter browsing. The known metabolite papyriferic acid was found to be a minor constituent of extracts of B. glandulosa.},
	keywords = {ANTIFEEDANT, BETULA-GLANDULOSA, DAMMAR-24-ENE-12-BETA-O-ACETYL-20(S)-OL-3-ONE, DEACETOXYPAPYRIFERIC ACID, DETER BROWSING, LEPUS-AMERICANUS, NMR, PAPER BIRCH, PAPYRIFERIC ACID, SNOWSHOE HARES},
	isbn = {0031-9422},
	url = {<Go to ISI>://A1992JC92000016},
	author = {Williams, D. E. and Sinclair, A. R. E. and Andersen, R. J.}
}
@article {7057,
	title = {CHARACTERIZATION OF ZEOLITE-CRACKING CATALYSTS},
	journal = {Acs Symposium Series},
	volume = {452},
	year = {1991},
	note = {ISI Document Delivery No.: EZ014Times Cited: 2Cited Reference Count: 45},
	pages = {27-44},
	type = {Article},
	abstract = {The revolutionary zeolite cracking catalyst (synthetic Linde X and Y) was introduced commercially over 28 years ago, but considerable effort is still being expended on the improvement of its stability and catalytic properties. Decreasing the aluminum content of the zeolite framework and the replacing the rare-earth with the hydrogen form have greatly increased activity at the expense of stability. The thermal stability of the faujasites is fairly well understood, while the reasons for the increased catalytic activitity are still not fully known. The use of traditional and new techniques to elucidate the structure of synthetic faujasites with different silica alumina ratios, dealuminated by steaming and chemical treatment, and with and without faulting will be described. The migration and fixation of cations and the role of aluminum in the dealumination of the zeolite will be discussed. Very clean and highly dealuminated samples have been prepared that have removed some of the variables in determining the state of the framework and extra-framework aluminum.},
	keywords = {FAUJASITES, FRAMEWORK ALUMINUM, HIGH-SILICA, NMR, Y-ZEOLITES, ZSM-20},
	isbn = {0097-6156},
	url = {<Go to ISI>://A1991EZ01400003},
	author = {Kokotailo, G. T. and Fyfe, C. A. and Feng, Y. and Grondey, H.}
}
@inbook {7056,
	title = {CHARACTERIZATION OF ZEOLITE-CRACKING CATALYSTS},
	booktitle = {Fluid Catalytic Cracking Ii - Concepts in Catalyst Design},
	series = {Acs Symposium Series},
	volume = {452},
	year = {1991},
	note = {ISI Document Delivery No.: BS68MTimes Cited: 0Cited Reference Count: 0Proceedings PaperSYMP AT THE 200TH NATIONAL MEETING OF THE AMERICAN CHEMICAL SOC - FLUID CATALYTIC CRACKING 1 : CONCEPTS IN CATALYST DESIGNAUG 26-31, 1990WASHINGTON, DCAMER CHEM SOC, DIV PETR CHEM},
	pages = {27-44},
	publisher = {Amer Chemical Soc},
	organization = {Amer Chemical Soc},
	address = {Washington},
	keywords = {FAUJASITES, FRAMEWORK ALUMINUM, HIGH-SILICA, NMR, Y-ZEOLITES, ZSM-20},
	isbn = {0-8412-1908-7},
	url = {<Go to ISI>://A1991BS68M00003},
	author = {Kokotailo, G. T. and Fyfe, C. A. and Feng, Y. and Grondey, H.},
	editor = {Occelli, M. L.}
}
@article {7001,
	title = {EFFECT OF CHAIN-LENGTH ON ORIENTATIONAL ORDER OF A SERIES OF SHORT-CHAIN CARBOXYLIC-ACIDS DISSOLVED IN A NEMATIC LIQUID-CRYSTAL},
	journal = {Journal of Magnetic Resonance},
	volume = {95},
	number = {1},
	year = {1991},
	note = {ISI Document Delivery No.: GL020Times Cited: 1Cited Reference Count: 22},
	month = {Oct},
	pages = {32-40},
	type = {Article},
	keywords = {BARRIER, butane, MATRIX, MOLECULAR-STRUCTURE, NMR, PHASES, ROTATION, SPIN-ECHO SPECTROSCOPY},
	isbn = {0022-2364},
	url = {<Go to ISI>://A1991GL02000003},
	author = {Delikatny, E. J. and Heldman, M. A. and Burnell, E. E.}
}
@article {7080,
	title = {RUBROLIDES-A-H, METABOLITES OF THE COLONIAL TUNICATE RITTERELLA-RUBRA},
	journal = {Journal of Organic Chemistry},
	volume = {56},
	number = {22},
	year = {1991},
	note = {ISI Document Delivery No.: GM576Times Cited: 53Cited Reference Count: 25},
	month = {Oct},
	pages = {6275-6280},
	type = {Article},
	abstract = {Rubrolides A (1) to H (8), a new family of biologically active tunicate metabolites, have been isolated from Ritterella rubra. The structures of the rubrolides were solved by a combination of spectroscopic analysis and chemical interconversions. Rubrolides B (2) and H (8) represent some of the first chlorinated metabolites known from tunicates. The rubrolides are potent in vitro antibiotics and they show moderate but selective inhibition of protein phosphatases 1 and 2A.},
	keywords = {C-13 ASSIGNMENTS, CARIBBEAN TUNICATE, ECTEINASCIDIA-TURBINATA, H-1, MARINE NATURAL-PRODUCTS, NMR, SIGILLINOIDES},
	isbn = {0022-3263},
	url = {<Go to ISI>://A1991GM57600012},
	author = {Miao, S. C. and Andersen, R. J.}
}
@article {7083,
	title = {TRITERPENOID GLYCOSIDES FROM THE NORTHEASTERN PACIFIC MARINE SPONGE XESTOSPONGIA-VANILLA},
	journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie},
	volume = {69},
	number = {9},
	year = {1991},
	note = {ISI Document Delivery No.: GH861Times Cited: 7Cited Reference Count: 13},
	month = {Sep},
	pages = {1352-1364},
	type = {Article},
	abstract = {Isoxestovanin A (6), xestovanin B (7), xestovanin C (8), dehydroxestovanin A (9), epidehydroxestovanin A (10), dehydroxestovanin C (11), and secodehydroxestovanin A (12), seven new triterpenoid glycosides, have been isolated from the Northeastern Pacific sponge Xestospongia vanilla. The structures of the metabolites were determined by a combination of spectroscopic analysis and chemical degradation. The aglycone of 6 has the new isoxestovanane triterpenoid carbon skeleton. Compounds 7, 8, and 11 are the first X. vanilla triterpenoid glycosides known to contain three monosaccharide subunits.},
	keywords = {C-13 ASSIGNMENTS, GLYCOSIDE, H-1, NMR, SPONGE, SUGARS, TRITERPENOID, XESTOSPONGIA},
	isbn = {0008-4042},
	url = {<Go to ISI>://A1991GH86100003},
	author = {Morris, S. A. and Northcote, P. T. and Andersen, R. J.}
}
