th  - 1987 - 51st ENC Conference

MK39
A Partial Excitation Method in Two-dimensional Nuclear Mag-
netic Resonance Spectroscopy Using a Tailored Pulse Having
a Sinc Function Shape
Muneki Ohuchl, Kazuo Furlhata~ and Haruo Seto~
JEOL Co., Nakagami, Akishima, Tokyo, ~lnstitute of Applied
Microbiology, University of Tokyo, Bunkyo-ku, Tokyo, Japan
Two-dimensional (2D) NMR spectroscopy has a disadvantage
that cross-peak patterns can not be analyzed in detail due
to the low digital resolution caused by the limited capacity
of data memory and by the limited measurement time. This
shortcoming can be eliminated by measuring a narrow spectral
region using partial excitation pulses. A slnc function
pulse can excite signals within a narrow frequency range,
while the side lobes produced from a rectangular pulse ex-
cite undesirable neighbor signals outside the range.
We have developed the partial excitation method in 2D NMR
spectroscopy[l] by using a tailored pulse produced from a
sinc function type pulse, and the digital resolution of 2D
NMR spectra has been enhanced several times by using this
method. Increased digital resolution allows recognition of
cross-peak patterns and coupling constants can be determined
from their patterns.
In this paper, application of this method to COSY and
HMBC[2](Heteronuclear Multiple Bond Connectivity) will be
reported.
I) M.Ohuchi et.al., J.Magn.Reson. in press.
M.Ohuchl et.al., 25th NMR Conference Tokyo (1986)
2) A.Bax et.al., J.Am.Chem. Soc., I08 2093 (1986)