Carbon-13 NMR spectroscopy of sesquiterpenes. 3. Synthesis and carbon-13 NMR spectral data of 4.alpha.,5.alpha.- and 4.beta.,5.beta.-epoxyeudesmanolides. Configuration and .gamma. effect of the oxirane ring
摘要:
The epoxide eudesmanolides 14-21, which constitute epimeric pairs with respect to the configuration of the oxirane ring, have been synthesized in a stereochemically unambiguous way. Comparison of their C-12 NMR spectra with those of the parent olefins 10-13 does not, however, reveal any significant correlation between the configuration of the oxirane ring and the shifts undergone by the signals of the gamma carbon atoms C-1/C-2/C-7/C-9/C-14.
Carbon-13 NMR spectroscopy of sesquiterpenes. 3. Synthesis and carbon-13 NMR spectral data of 4.alpha.,5.alpha.- and 4.beta.,5.beta.-epoxyeudesmanolides. Configuration and .gamma. effect of the oxirane ring
作者:Miguel Carda、Juan F. Sanz、J. Alberto Marco
DOI:10.1021/jo00029a006
日期:1992.1
The epoxide eudesmanolides 14-21, which constitute epimeric pairs with respect to the configuration of the oxirane ring, have been synthesized in a stereochemically unambiguous way. Comparison of their C-12 NMR spectra with those of the parent olefins 10-13 does not, however, reveal any significant correlation between the configuration of the oxirane ring and the shifts undergone by the signals of the gamma carbon atoms C-1/C-2/C-7/C-9/C-14.