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Effects of misoptimization of the BIRD pulse on one-bond modulation effects in long-range heteronuclear chemical shift correlation spectra

✍ Scribed by Miguel Salazar; Luis R. Soltero; Andrew S. Zektzer; Gary E. Martin

Publisher: John Wiley and Sons
Year: 1989
Tongue: English
Weight: 383 KB
Volume: 27
Category: Article
ISSN: 0749-1581
DOI: 10.1002/mrc.1260270205

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✦ Synopsis

BIRD pulses have been shown to provide an effective means of decoupling ow-bond modulation of long-range response intensity. It is not possible to optimize the BIRD pulse effectively wben tbere is a range of one-bond coupling constants. To examine the effects of misoptimization of the fixed delays (r) in the BIRD pulse, the simple alkaloid oorharmane was employed. Long-range heteronuclear correlation spectra were recorded oing a modified pulse sequence containing a BIRD pulse midway through the A2 interval The experiment was optimized for 103 and 11.1 Hz, which correspond to a valley a d a peak in the response intensity curve when the experiment is performed without the BIRD pulse midway through A,. Tbe delays in the BIRD pulse were varioasly optimized for values ranging from 80 to 175 Hz. Tbe results suggest tbat the BIRD pulse is effective in decoupliag one-bond modulatious of response intensity even when the t delays are grossly misoptimiZea for the one-bod coupling constant in question.

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