1 H and 13 C NMR spectral data for phytochelatin, NH 3 C --Glu-Cys 2 -Gly-COO , were assigned by a combination of one-( 1 H, 13 C) and two-dimensional (DQF-COSY, CH-COSY, HMBC) NMR experiments.
1H and 13C NMR assignment of theaflavin, theaflavin monogallate and theaflavin digallate
β Scribed by Adrienne L. Davis; Ya Cai; Alan P. Davies
- Publisher
- John Wiley and Sons
- Year
- 1995
- Tongue
- English
- Weight
- 356 KB
- Volume
- 33
- Category
- Article
- ISSN
- 0749-1581
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β¦ Synopsis
Abstract
Theaflavin, theaflavin monogallate and theaflavin digallate were isolated from black tea leaves and studied by 1D and 2D NMR techniques, thus allowing unambiguous assignment of the ^1^H and ^13^C resonances of these complexes. Earlier studies have not yielded ^13^C data of equal reliability, especially for the benzotropolone moiety of these molecules, and consequently the data given here will be of use in future studies of natural products isolated from tea. The utility of the 2D proton detected longβrange ^13^Cο£Ώ^1^H correlation experiment (HMBC) in the study of polyphenolic complexes is demonstrated by these results.
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