Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Probing heteronuclear N-15-O-17 and C-13-O-17 connectivities and proximities by solid-state NMR spectroscopy
AU - Hung, Ivan
AU - Uldry, Anne-Christine
AU - Becker-Baldus, Johanna
AU - Webber, Amy L.
AU - Wong, Alan
AU - Smith, Mark E.
AU - Joyce, Sin A.
AU - Yates, Jonathan R.
AU - Pickard, Chris J.
AU - Dupree, Ray
AU - Brown, Steven P.
PY - 2009/2/1
Y1 - 2009/2/1
N2 - Heteronuclear solid-state magic-angle spinning (MAS) NMR experiments for probing N-15-O-17 dipolar and J couplings are presented for [H-2(NH3),1-C-13,N-15,O-17(2)]glycine center dot(HCl)-H-2 and [N-15(2), O-17(2)]uracil. Two-dimensional N-15-O-17 correlation spectra are obtained using the R-3-HMQC experiment; for glycine center dot(HCl)-H-2, the intensity of the resolved peaks for the C=O and C-(OH)-H-2 O-17 resonances corresponds to the relative magnitude of the respective N-15-O-17 dipolar couplings. O-17-N-15 REDOR curves are presented for glycine center dot(HCl)-H-2; fits of the initial buildup (Delta S/S <0.2) yield effective dipolar couplings in agreement with (+/- 20%) the root-sum-squared dipolar couplings determined from the crystal structure. Experimental N-15-O-17 REAPDOR curves for the N-15 resonances in glycine center dot(HCl)-H-2 and uracil fit well to the universal curve presented by Goldbourt et al. (J. Am. Chem. Soc. 2003, 125,11194). Heteronuclear C-13-O-17 and N-15-O-17 J couplings were experimentally determined from fits of the quotient of the integrated intensity obtained in a heteronuclear and a homonuclear spin-echo experiment, S-Q(tau) = S-HET(tau)/S-HOM(tau). For glycine center dot(HCl)-H-2, (1)J(CO) was determined as 24.7 +/- 0.2 and 25.3 +/- 0.3 Hz for the C=O and C-(OH)-H-2 resonances, respectively, while for uracil, the average of the two NH center dot center dot center dot O hydrogen-bond-mediated J couplings was determined as 5.1 +/- 0.6 Hz. In addition, two-bond intramolecular J couplings, (2)J(OO) = 8.8 +/- 0.9 Hz and (2)J(N1,N3) = 2.7 +/- 0.1 Hz, were determined for glycine center dot(HCl)-H-2 and uracil, respectively. Excellent agreement was found with J couplings calculated using the CASTEP code using geometrically optimized crystal structures for glycine center dot HCl [(1)J(CO)(C=O) = 24.9 Hz, (1)J(CO)(C-OH) = 27.5 H Z, (2)J(OO) = 7.9 Hz] and uracil [(2h)J(N1,O4) = 6.1 Hz, (2h)J(N3,O4) = 4.6 Hz, (2)J(N1,N3) = 2.7 Hz].
AB - Heteronuclear solid-state magic-angle spinning (MAS) NMR experiments for probing N-15-O-17 dipolar and J couplings are presented for [H-2(NH3),1-C-13,N-15,O-17(2)]glycine center dot(HCl)-H-2 and [N-15(2), O-17(2)]uracil. Two-dimensional N-15-O-17 correlation spectra are obtained using the R-3-HMQC experiment; for glycine center dot(HCl)-H-2, the intensity of the resolved peaks for the C=O and C-(OH)-H-2 O-17 resonances corresponds to the relative magnitude of the respective N-15-O-17 dipolar couplings. O-17-N-15 REDOR curves are presented for glycine center dot(HCl)-H-2; fits of the initial buildup (Delta S/S <0.2) yield effective dipolar couplings in agreement with (+/- 20%) the root-sum-squared dipolar couplings determined from the crystal structure. Experimental N-15-O-17 REAPDOR curves for the N-15 resonances in glycine center dot(HCl)-H-2 and uracil fit well to the universal curve presented by Goldbourt et al. (J. Am. Chem. Soc. 2003, 125,11194). Heteronuclear C-13-O-17 and N-15-O-17 J couplings were experimentally determined from fits of the quotient of the integrated intensity obtained in a heteronuclear and a homonuclear spin-echo experiment, S-Q(tau) = S-HET(tau)/S-HOM(tau). For glycine center dot(HCl)-H-2, (1)J(CO) was determined as 24.7 +/- 0.2 and 25.3 +/- 0.3 Hz for the C=O and C-(OH)-H-2 resonances, respectively, while for uracil, the average of the two NH center dot center dot center dot O hydrogen-bond-mediated J couplings was determined as 5.1 +/- 0.6 Hz. In addition, two-bond intramolecular J couplings, (2)J(OO) = 8.8 +/- 0.9 Hz and (2)J(N1,N3) = 2.7 +/- 0.1 Hz, were determined for glycine center dot(HCl)-H-2 and uracil, respectively. Excellent agreement was found with J couplings calculated using the CASTEP code using geometrically optimized crystal structures for glycine center dot HCl [(1)J(CO)(C=O) = 24.9 Hz, (1)J(CO)(C-OH) = 27.5 H Z, (2)J(OO) = 7.9 Hz] and uracil [(2h)J(N1,O4) = 6.1 Hz, (2h)J(N3,O4) = 4.6 Hz, (2)J(N1,N3) = 2.7 Hz].
KW - DOUBLE-RESONANCE NMR
KW - ANGLE-SPINNING NMR
KW - INTEGER QUADRUPOLAR NUCLEI
KW - QUANTUM CROSS-POLARIZATION
KW - MEDIUM-RANGE ORDER
KW - ROTATIONAL-ECHO
KW - REAPDOR NMR
KW - O-17 NMR
KW - MAS NMR
KW - DIPOLAR INTERACTIONS
U2 - 10.1021/ja805898d
DO - 10.1021/ja805898d
M3 - Journal article
VL - 131
SP - 1820
EP - 1834
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 1520-5126
IS - 5
ER -