Assignment of 1H and 13C spectra and investigation of hindered side‐chain rotation in lupeol derivatives †

@article{Burns2000AssignmentO1,
  title={Assignment of 1H and 13C spectra and investigation of hindered side‐chain rotation in lupeol derivatives †},
  author={D. C. Burns and W. Reynolds and Greg O. Buchanan and P. Reese and R. Enr{\'i}quez},
  journal={Magnetic Resonance in Chemistry},
  year={2000},
  volume={38}
}
  • D. C. Burns, W. Reynolds, +2 authors R. Enríquez
  • Published 2000
  • Chemistry
  • Magnetic Resonance in Chemistry
    • Complete 1H and 13C spectral assignments are reported for lupeol (1a) and two derivatives where the C‐30 methyl group is replaced by CH2OH (1b) and HC O (1c). Compound 1c shows conformationally dependent substituent effects on 1H chemical shifts. It also shows line broadening of some 13C signals at 25 °C, suggesting hindered rotation of the side‐chain group. This is confirmed by low‐temperature spectra which show splitting of broadened peaks into pairs in a ca 2 : 1 area ratio. The free energy… CONTINUE READING
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