th  - 1988 - 51st ENC Conference

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I 44
TWO DIMENSIONAL LINEAR PREDICTION NMR SPECTROSCOPY
] •
Henrik Gesmar and Jens J. Led
University of Copenhagen, Dept. of Chemical Physics
The H.C. 8rsted Institute, 5, Universitetsparken
DK-2100 Copenhagen, Denmark.
Linear prediction has been introduced into the field of NMR spectroscopy as a valu-
able method of quantitative spectral estimation (1,2). Its applicability has been de-
monstrated even in case of broad band spectra with many narrowly spaced resonances (3),
i.e. cases where LSQ curve fitting procedures (4) would seem to be unfeasible.
In the present study it is demonstrated that the application of the linear predic-
tion principle can be extended to include two dimensional N!IR spectroscopy, without
increasing the computation time drastically.
Examples are presented and the advantages as well as the pitfalls of the procedure
are discussed.
(I) H. Barkhuijsen, R. de Beer, W.M.M.Jo Bov6e, and D. van Ormondt,
J. !.lag n. Reson. 6_~I, 465 (1985).
(2) J. Tang, C.P. Lin, M.K. Bov~nan, and J.R. Norris, J_. ~agn. Reson. 6_22, 167 (1985).
(3) H. Gesmar and J.J. Led, J. !4agn. Reson. (1988). In press.
(4) F. Abildgaard, H. Gesmar, and J.J. Led, J. Magn. Reson. (1988). In press.
45 I INTERGLYCOSIDIC 13C_I H COUPLING CONSTANTS. AN APPROACH TO
D ACCHARIDE AND POLYSACCHARIDE CONFORMATIONS. C. Morat, LEDSS, University of Grenoble
R.F. Taravel, CERMAV-CNRS: F38402 Saint Martin d'Heres FRANCE.
Interglycosidic C-H coupling constants have been measured for different
disaccharides (methyl B-cellobioside, methyl B-maltoside, octa-O acetyl B-gentiobiose
methyl B-isomaltoside, B-D-mannobiose) and one oolysaccharide (5-3-6 triacetyl
cellulose) in natural abundance by the selective 2D-J heteronuclear exoeriment.
Their values give access to the torsion angle of the glycosidic link when used in
conjunction with a KARPLUS-tyDe relationship.
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