th  - 1988 - 51st ENC Conference

s4 IA 13C CP/MAS AND 2H WIDELINE VARIABLE TEMPERA-
TURE STUDY OF BECLOMETHASONE DIPROPIONATE--HEXANE IN-
CLUSION COMPLEX: Thomas A. Early1-* and Mohindar S. Puar§, ~GE NMR
Instruments, Fremont, Califorina 94539 §Schering-Plough Corp., Bloomfield,
New Jersey 07003
A solid inclusion complex, beclomethasone dipropionate--hexane, has
been previously studied by magic angle spinning NMR methods 1. The complex
presents an interesting system for CP/MAS study because of the wide range of
motions present. For example, even though the hexane methyl reorients at a rate
consistent with liquid-like tumbling, the hexane carbons easily cross polarize.
When the hexane guest molecule is deuterated, and wideline dueterium
spectra are obtained at a variety of temperatures ranging from 100 ° C to below
-160 ° C, lowering the sample temperature results in an unexpected narrowing of
2H Pake powder pattern resonances of the hexane-d]4 guest molecule. This in-
teresting temperature behavior leads to models that 13C CP/MAS can distinguish.
1 "Carbon-13 Nuclear Magnetic Resonance Studies of a Solid Inclusion Com-
plex", T.A. Early, J.F. Haw, A. Bax, G.E. Maciel, and M.S. Puar, The Journal of
Physical Chemistry, 88, 324(1984).
SS
I
HUMAN IN VIVO SPECTROSCOPY AT 4.0T
Dietmar Hentschel, Jurgen Vetter, Ralf Ladebeck, and Michael J. AIbright*
Siemens AG, D-8520 Erlangen, FDG
A 4 T six-coil SCM with a warm bore of 1.25 m diameter was designed
with high homogeneity for use with in vivo spectroscopy. Computer optimized
design was used to correct terms up to 10th order. The magnet can be ramped
to 4 T in 1 hour. The rated current is 376 A, and the stored field energy is 39
MJ. The field drift is less than 3.6 x 10-8/h, and bare homogeneity of 100 ppm
can be corrected to less than +2.5 ppm for a 50 cm dsv. The total magnet
weight is 10.6 tons.
Increased spectral dispersion will be shown by comparison with 2 T
spectra. Human in vivo 31p spectra at 4 T show resolution of the different
PDE resonances, and, on some spectra, separation of the dinucleotides and
nucleoside diphosphosugars upfield of the (z-ATP peak.
High field RF penetration will be demonstrated with a 1H image at 4 T.
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