## Abstract Carbonโ13 spectral assignments of three friedelanes and nineteen secofriedelanes have been made from mutual correlations, 2D XโH correlation analyses and comparison with the carbon shifts of friedelin, which were firmly established by an INADEQUATE experiment that required reassignment
Carbon-13 resonance assignments of some friedelanes and taraxasteranes
โ Scribed by Amarendra Patra; Apurba K. Mukhopadhyay; Alok K. Mitra
- Publisher
- John Wiley and Sons
- Year
- 1981
- Tongue
- English
- Weight
- 299 KB
- Volume
- 17
- Category
- Article
- ISSN
- 0749-1581
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โฆ Synopsis
Abstract
Carbonโ13 signal assignments of taraxasteryl acetate, taraxasteryl palmitate, taraxasterol and epiโfriedelinyl acetate are reported. Some signal assignments of the friedelanones, reported recently by others, are inconsistent and require revision.
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## Abstract The ^13^C NMR spectra of pure __exo__โ2โnorbornyltrimethylstannane and a mixture of the __exo__โ and __endo__โisomers have been recorded. ^1^Hโ^13^C polarization transfer spectra have been obtained and require the previously reported assignments for Cโ3 and Cโ4 in the __exo__โisomer to
REFERENCE DATA causes the electron density to be comparatively lower at C-3 and C-5 than at C-2 and C-4, so that the former signals resonate at lower fields. Distinction between the signals of the C-2/C-4 and C-3/C-5 pairs was achieved by comparing the C-H coupling patterns of 5 and 1. Compounds 1,