title: An NMR crystallography study of the hemihydrate of 2', 3'-O-isopropylidineguanosine.
abstract: An NMR crystallography study of the hemihydrate of 2', 3'-O-isopropylidineguanosine (Gace) is presented, together with powder X-ray diffraction and thermogravimetric analysis. (1)H double-quantum and (14)N-(1)H HMQC spectra recorded at 850MHz and 75kHz MAS (using a JEOL 1mm probe) are presented together with a (1)H-(13)C refocused INEPT spectrum recorded at 500MHz and 12.5kHz MAS using eDUMBO-122(1)H homonuclear decoupling. NMR chemical shieldings are calculated using the GIPAW (gauge-including projector augmented wave) method; good two-dimensional agreement between calculation and experiment is observed for (13)C and (1)H chemical shifts for directly bonded CH and CH3 peaks. There are two Gace molecules in the asymmetric unit cell: differences in specific (1)H chemical shifts are rationalised in terms of the strength of CH-π and intermolecular hydrogen bonding interactions.
authors: Department of Physics, University of Warwick, Coventry CV4 7AL, UK.
authors: G N Manjunatha
authors: GN
authors: Reddy
authors: Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK.
authors: Daniel S
authors: DS
authors: Cook
authors: Department of Physics, University of Warwick, Coventry CV4 7AL, UK.
authors: Dinu
authors: D
authors: Iuga
authors: Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK.
authors: Richard I
authors: RI
authors: Walton
authors: Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK.
authors: Andrew
authors: A
authors: Marsh
authors: Department of Physics, University of Warwick, Coventry CV4 7AL, UK. Electronic address: S.P.Brown@warwick.ac.uk.
authors: Steven P
authors: SP
authors: Brown
mesh_terms: D018360:Crystallography, X-Ray; D006151:Guanosine / Q000031:analogs & derivatives* / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D014867:Water / Q000737:chemistry*
chemical_list: C427043:2',3'-isopropylideneguanosine; D014867:Water; D006151:Guanosine
keywords: (1)H DQ; (1)H–(13)C; (14)N–(1)H; Dipolar coupling; GIPAW; Guanosine; Hydrate; J coupling; MAS; NMR