Phase-sensitive NOESY spectrum

Finally, the nuclear Overhauser effect can be utilized to construct a 2D spectrum where cross-peaks correspond to protons close in space (phase-sensitive NOESY spectrum). 

Fig. (3). Phase-sensitive NOESY spectrum of saponarioside C from Saponaria officinalis (the mixing time was 600 msec). Note that both the inter-residue (bold labeled) and intra-residue NOEs were observed. For the a-D-galactose moiety, the only intra-residue NOE noted is between H, and H2. For all other sugar units, the intra-residue NOEs between H,/H3 and H,/H5 are observed.

The phase sensitive NOESY spectrum of 43 showed cross-peaks as shown in the computer-generated 3D drawing (Fig. 6). The relative configurations at C-7, C-12, C-13, and C-15 in part A were based on the NOESY correlations of H-6b/H-15, H-12/H-lOb and H-3/H-14b, while the piperidine and cyclohexane (C-7, C-8, and C-12 C-15) rings both adopted chair conformations. On the other hand, the corresponding NOESY... 

Figure 5.44 (a) Phase-sensitive absorption-mode NOESY spectrum of bovine phos-... 

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