Amide H signal

Determination of N—H bond lengths from the dipolar spinning sideband pattern of amide H signals... 

Observation of the amide H signal of N-lahelled poly(L-alanines)... 

Prototropic tautomerism of 2-alkylated tetrahydro species 21 is solvent dependent, tautomers 21a and 21b being identified as the major species present in DMSO-dimethyl sulfoxide) and deuterochloroform, respectively <2000HCA1693> by NOE experiments. Acetylated analogue 22 appears to behave similarly, although in this case the spectrum is complicated by the presence of amide rotamers. As judged from the N-H signals observed in H NMR spectrum, the major species in deuterochloroform is 22a, whereas, in DMSO-i4> the tautomeric equilibrium constant approaches unity, and both tautomers are present. 

Fig. 5.4.15a,b Parts of two-dimensional total correlated spectroscopy spectra of human bile (a) and a mixture of standard solutions of GCA, GDCA, TCA and TDCA (b). These spectra show the connectivity of amide proton signals to H-25 and/or H-26 protons of glycine and/or taurine conjugated bile acids (reprinted from [40])... 

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