No abstract

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.

Three new Daphne diterpenes, yuanhuaoate A (1), yuanhuaoate B (2), and yuanhuaoate C (3), were isolated from the buds of Daphne genkwa Sieb. et Zucc. processed by rice vinegar. Their structures and relative configurations were established by analysis of spectroscopic data. Their absolute configurations were assigned by the CD technique, applied for the first time to Daphne diterpenes.

One new steroid alkaloid, 12beta-hydroxylveratroylzygadenine (1) and four known compounds, verdine (2), jervine (3), veramarine (4), and veratroylzygadenine (5), have been isolated from the roots and rhizomes of Veratrum nigrum L. processed by rice vinegar. Their structures were established through a combined analysis of physicochemical properties and spectroscopic evidence. The assay results revealed that compounds 1, 4, and 5 exhibited cell toxicity against human HL-60 cells with IC50 values 52.67, 52.90, and 56.51 micromol/l, respectively.