Structure Identification: |
Chem Pharm Bull (Tokyo). 1999 Mar;47(3):375-82. | The bakkenolides from the root of Petasites formosanus and their cytotoxicity.[Pubmed: 10400491] | METHODS AND RESULTS:
Thirty-two new bakkenolides, bakkenolide Db (1) bakkenolide Dh(7), bakkenolide Fa(8), bakkenolide Fb(9), bakkenolide I(10) bakkenolide M(14), bakkenolide Na(15), bakkenolide Nb(16), bakkenolide O(17) bakkenolide T(22), bakkenolide Ua (23), bakkenolide Ub(24), bakkenolide V(25) bakkenolide X(27), bakkenolide Ya(28), bakkenolide Yb(29), bakkenolide Za(30), bakkenolide Zb(31) and Bakkenolide III(32), from the roots of Petasites formosanus together with thirty known compounds were isolated. The structures were characterized by spectral analysis.
CONCLUSIONS:
The locations, C-1 and/or C-9 of bakkenolide skeleton, of the substituents, such as acetoxy, isobutyroyloxy and isovaleroyloxy groups, can be determined by the chemical shifts of their signals and the H-1 and/H-9 in the 1H-NMR spectra. The cytotoxicity was also discussed. |
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