The structural elucidation of 24 xanthones with di β erent substitution patterns was performed by spectroscopic methods, namely 2D NMR techniques, such as correlation spectroscopy (COSY), nuclear Overhauser e β ect (NOE), heteronuclear correlation (HETCOR) and a 1D NMR technique, selective insensitive
13C NMR spectroscopy of tri- and tetracyclic quinolizidine alkaloids. Compilation and discussion
β Scribed by B. Mikhova; H. Duddeck
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- English
- Weight
- 317 KB
- Volume
- 36
- Category
- Article
- ISSN
- 0749-1581
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β¦ Synopsis
A comprehensive collection of 13C chemical shifts of 159 tri-and tetracyclic quinolizidine alkaloids (sparteine derivatives) is presented. The data are discussed in terms of substituent e β ects, molecular geometries and protonation e β ects. Some IR, 1H and 15N NMR and MS data are included.
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