Adiabatic pulses in 1 H– 15 N direct and long‐range heteronuclear correlations

The application of adiabatic inversion pulses to the detection of 1 H– 15 N heteronuclear correlations is described. The pulse sequences studied were gHSQC, CRISIS‐gHSQC, gHMBC and CRISIS‐gHMBC. The poor inversion quality of rectangular 180° X pulses can lead to a loss of signal at the peripheries of the spectrum. Replacing these pulses with adiabatic sweeps significantly improves sensitivity across the potentially large 15 N spectral window. Satellite spectrum profiles are shown to demonstrate the increase in sensitivity when employing adiabatic pulses on wide spectral widths. Additionally, the active pharmaceutical nizatidine was used as a model compound to demonstrate the improvements in the long‐range correlation data. Copyright © 2004 John Wiley & Sons, Ltd.