✦ LIBER ✦

Application of 1H NMR bi-selective relaxation times to conformational analysis in solution

✍ Scribed by Makiko Sugiura; Narao Takao; Hideaki Fujiwara

Publisher: John Wiley and Sons
Year: 1988
Tongue: English
Weight: 483 KB
Volume: 26
Category: Article
ISSN: 0749-1581
DOI: 10.1002/mrc.1260261204

No coin nor oath required. For personal study only.

✦ Synopsis

The usefulness of 'H bi-selective relaxation times ( 2 ' : ' ) and selective relaxation times (T,') for structure and conformation determination is emphasized. A pulse sequence has been devised which provides the apparent observed T : ' . The cross-relaxations (q,) or Fi, values are derived from the observed T : ' and T , ' values. The ui, values can be correlated with the H-H distances (r,J and can be used for conformational analysis or structure determination. The Fi, values, which indicate the fractional contribution to the dipolar relaxation of proton i via the interaction with protonj(i #J), can be compared with the NOE values. 2-Vinylpyridine was chosen as a model compound and three types of T, values were measured for its protons. Its conformation in CDCl, solution is discussed based on the correlation between the uii obtained and the ri, values. A conformational equilibrium is suggested. KEY WORDS Bi-selective relaxation time Selective relaxation time Cross-relaxation Structure and conformation determination 2-Vinylpyridine

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