## Abstract Carbon‐13 NMR chemical shifts are reported for six angular and one linear dichloropyridoquinolines in CDCl~3~. The chemical shift assignments have been made using model compounds, fully coupled spectra, selective proton decoupling and results from lanthanide shift studies. Chlorine subs
Carbon-13 nuclear magnetic resonance studies of leonurine hydrochloride and its analogues
✍ Scribed by Gordon E. Langford; Peter Yates; Hin Wing Yeung; Kin Fai Cheng
- Publisher
- John Wiley and Sons
- Year
- 1980
- Tongue
- English
- Weight
- 384 KB
- Volume
- 14
- Category
- Article
- ISSN
- 0749-1581
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
The ^13^C NMR spectra of leonurine hydrochloride and thirteen of its analogues in DMSO‐d~6~ have been analyzed. Changes in the aromatic substituents have no significant effect on the chemical shifts of the side chain methylene carbons indicating that they do not influence the conformation of the latter. Observed deviations from additivity of substituent effects for the methylene carbon chemical shifts suggest that the methylene side chains of these compounds may be more tightly coiled than are the corresponding n‐alkanes. In representative cases no change in conformation is evident in 50% aqueous DMSO‐d~6~ solutions, indicating that similar considerations may apply in aqueous media.
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