Articles

Dammarane-type triterpenoid saponins from Bacopa monniera.

Author

Garai S, Mahato SB, Ohtani K, Yamasaki K

Date

6/1996

Journal

Phytochemistry

Abstract

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-arabinopyranosyl-+ ++jujubogenin, 3-O- [alpha-L-arabinofuranosyl (1--> 2)alpha-L- arabinopyranosyl]pseudojujubogenin and 3-O-[beta-D-glucopyranosyl (1 - ->3)[alpha-L-arabinofuranosyl (1--> 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.