th  - 1987 - 51st ENC Conference

WK4
P.E.COSY, DOUBLE QUANTUM FILTERED RELAY SPECTROSCOPY AND MORE.
Stephen C. Brown, Paul L. Weber & Luciano Mueller
Smith Kline & French Laboratories
709 Swedeland Road, Mail Code L940
Swedeland, Pennsylvania 19479.
Whenever one gains the impression that some aspect of NMR is
becoming exhausted, a new twist is stumbled upon that opens up new
avenues of research. For instance, we recently found a new procedure
to purge the phases in COSY spectra, which we subsequently utilized to
generate E.COSY 1 type spectra. This experiment involves the reduction
of the flip angle in the mixing pulse combined with the said phase
purging. The resulting spectra looked impressive enough to leave the
impression that some people may want to see a name associated with
this procedure; how about primitive or P. E.COSY 2.
We also applied dual double quantum filtering procedure to the
RELAY experiment as originally proposed by O. Sorensen 3. To our
delight we obtained superb results in a small protein (ubiquitin),
which suggests that this procedure may become the standard RELAY
technique. For people who are in desperate need of names may we call
this DQFRELAY or DRECKSY (true meaning to be revealed upon request).
Furthermore, we found an optimized combination of selective
excitation and homogeneity spoiling in the 2DNOE experiment to
suppress the solvent peak in H20 solution. These results and more we
wish to present.
References: 1. C. Criesinger, O. W. Sorensen and R. R.
Ernst, J. Amer. Chem. Soc. 107, 6394 (1985).
2. L. Mueller, J. Magn. Reson., March 1987.
3. O. W. Sorensen, Ph.D. thesis, ETH #7658
(1984).