RESUMO
Three new minor dammarane saponins, quinquenosides L10 (1), L14 (2), and L16 (3), were isolated from the leaves and stems of Panax quinquefolium L. By the combination of one- and two-dimensional NMR techniques and MS spectroscopic analysis, their structures were established as 20-O-(alpha-L-arabinopyranosyl-(1-6)-O-beta-D-glucopyranosyl)-3-O-beta-D-glucopyranosyl-dammar-24-ene-3,12, 20-triol (1), 20-O-alpha-L-arabinopyranosyl-3-O-(beta-D-glucopyranosyl-(1-2)-O-beta-d-glucopyranosyl)-dammar-24-ene-3,12,20-triol (2), 3-O-(beta-D-glucopyranosyl-(1-2)-O-beta-d-glucopyranosyl)-20-O-(beta-D-glucopyranosyl-(1-6)-beta-D-glucopyranosyl)-dammarane-3,12,20,24,25-pentaol (3). The content of artemisinin was significantly enhanced by 3.0 mg l(- 1) of compounds 1, 2, and 3 in the callus of Artemisia annua.
