## Abstract The dipeptide alanylproline has been prepared with the proline residue both ^13^C (15%) and ^15^N (95%) enriched. ^15^N NMR spectra of alanylproline reveal signals for both possible conformations—__cis__ and __trans__—of the dipeptide backbone in solution. Different p__K__ values for bo
15N chemical shifts and one bond 15N1H coupling constants in simple amides
✍ Scribed by J. P. Marchal; D. Canet
- Publisher
- John Wiley and Sons
- Year
- 1981
- Tongue
- English
- Weight
- 294 KB
- Volume
- 15
- Category
- Article
- ISSN
- 0749-1581
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✦ Synopsis
Abstract
An indirect method is employed for determining the ^15^N parameters at the natural abundance level in a series of simple acyclic and cyclic amides. The one bond coupling constant, ^1^J(^15^N^1^H), and the ^15^N chemical shift are measured as a function of the carbonyl substituent group or the ring size and the nature of the solvent (CCl~4~ or H~2~O). These ^15^N parameters are related to the amide bond structure, the nitrogen configuration and possible intermolecular hydrogen bonding (amide‐amide or amide‐water).
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