| Abstract | Four new triterpenoid glycosides were isolated from the root bark of M. macrophylla , collected in Nepal. Their structures were determined as 3- O -β-D-glucopyranosyl- 28- O -α-L-rhamnopyranosyl-16α-hydroxy- 23-deoxyprotobassic acid, 28- O -β-D- glucopyranosyl-16α-hydroxy-23-deoxyprotobassic acid, 3- O -β-D-glucopyranosyl-28- O -α- L -rhamnopyranosyl-16α-hydroxyprotobassic acid, and 3- O -{[β-D-glucopyranosyl-(1 right arrow 6)]- O -α-L-rhamnopyranosyl-(1 right arrow 2)- O -β-D-glucopyranosyl-(1 right arrow 2)}- O -β-D-glucopyranosyl-(1 right arrow 3)- O -β-D-glucopyranosyl-cycloarta-22,24-dien- 27-oic acid (mussaendoside W). Four known triterpenoids, 3- O -acetyloleanolic acid, 3- O -acetyldaturadiol, rotundic acid and 16α-hydroxyprotobassic acid were also isolated. The structures of the new compounds were determined by several spectroscopic techniques including 2D NMR methods. Six compounds showed inhibitory activity against a periodontopathic bacterium, Porphyromonas gingivalis , but were inactive against the cariogenic organism, Streptococcus mutans . |