Adiabatic pulses in 1H-15N 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 degrees 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.
Hadden
Chad E
CE
Drug Disposition and Metabolism, Eli Lilly and Co., Indianapolis, Indiana 46285, USA. haddence@lilly.com
D003198:Computer Simulation; D009682:Magnetic Resonance Spectroscopy / Q000379:methods* / Q000592:standards*; D015394:Molecular Structure; D009587:Nitrogen Isotopes / Q000737:chemistry; D016567:Nizatidine / Q000737:chemistry*; D011522:Protons; D012015:Reference Standards; D012680:Sensitivity and Specificity
D009587:Nitrogen Isotopes; D011522:Protons; D016567:Nizatidine