Dammarane-type triterpenoid saponins from Bacopa monniera
1996
Garai, S. | Mahato, S.B. | Ohtani, K. | Yamasaki, K.
Three new dammarane-type triterpenoid saponins, bacopasaponins A, B and C, of biological interest have been isolated from the reputed Indian medicinal plant Bacopa monniera and identified as 3-O-alpha-L-arabinopyranosyl-20-O-alpha-L-arabiopyranos yl-jujubogenin, 3-O-[alpha-L-arabinofuranosyl (1 leads to 2)alpha-L-arabinopyranosyl]pseudojujubogenin and 3-O-[beta-D-glucopyranosyl (1 leads to 3)(alpha-L-arabinofuranosyl (1 leads to 2)alpha-L-arabinopyranosyl]pseudojujubogenin by spectroscopic methods and some chemical transformations. The hitherto undetermined configurations at C-20 and C-22 of pseudojujubogenin were elucidated by phase-sensitive ROESY, and 1H and 13C signals of the saponins were assigned by DEPT, 1H-1H COSY, HSQC and HMBC techniques.
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