Region-selective inverse-detected long-range heteronuclear chemical shift correlation using shaped pulses
โ Scribed by Ronald C. Crouch; Timothy D. Spitzer; Gary E. Martin
- Publisher
- John Wiley and Sons
- Year
- 1992
- Tongue
- English
- Weight
- 845 KB
- Volume
- 30
- Category
- Article
- ISSN
- 0749-1581
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โฆ Synopsis
Abstract
F~1~ regionโselected variants of the HMBC experiment were compared and evaluated. In particular, a significant advantage was demonstrated for an EโBURPโ2 pulse over a Gaussian 270ยฐ pulse for regionโselected applications. The Gaussian 270ยฐ pulse would still, however, be the preferred pulse for use in singleโresonance, onโresonance selective excitation. Data are presented from NMR spectrometers both equipped and not equipped with programmable pulse modulators (waveform generators). Pulse evaluations were performed using the simple heteroaromatic alkaloid quindoline; application of the technique to the important immunosuppressive cyclic peptide cyclosporinโA is also presented and discussed.
๐ SIMILAR VOLUMES
Techniques available for long-range heteronuclear chemical shift correlation are briefly reviewed. A new pulse sequence for long-range heteronuclear chemical shift correlation is described. Comparison of the results obtained using the new pulse sequence with those from conventional long-range optimi
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