The complete 1H and 13C assignment of two closely related isomeric triterpenoid derivatives (methyl 2a,3b-di-Oacetylolean-12-en-28-oate and methyl 2a,3a-di-O-acetylurs-12-en-28-oate) is described. In addition to 1D NMR methods, 2D shift-correlated NMR techniques (COSY, NOESY, HMBC and HMQC) were use
Total assignment of 1H and 13C NMR spectra of tectol and tecomaquinone I
โ Scribed by Telma L. G. Lemos; Sonia M. O. Costa; Otilia D. L. Pessoa; R. Braz-Filho
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 52 KB
- Volume
- 37
- Category
- Article
- ISSN
- 0749-1581
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โฆ Synopsis
Conventional one-dimensional NMR methods and two-dimensional shift-correlated NMR experiments (COSY, HMQC, HMBC) were used for 1 H and 13 C chemical shift assignments of two naphthoquinone dimers tectol and tecomaquinone I isolated from Lippia sidoides.
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