Two new flavonol glycosides, namely kaempferol 3-O-b-D-glucopyranosyl-(1fi4)-a-L-rhamnopyranosyl-(1fi6)-b-Dgalactopyranoside (1) and quercetin 3-O-600-(3-hydroxyl-3-methylglutaryl)-b-D-glucopyranoside (2), have been isolated from the aerial parts of Gymnema sylvestre and Euphorbia ebracteolata, respectively. Their structures were determined on the basis of chemical and spectroscopic methods.

Bioassay-guided fractionation of the ethanol extract of the roots and rhizomes of Veratrum taliense yielded two new and thirteen known steroidal alkaloids. The structures of the two new compounds, neoverataline A and B, were established by extensive spectroscopic analyses to be 3,4-secocevane-4, 9-olid-14,15,16,20-tetra-ol-3-oic acid and 3, 4-secocevane-4, 9-olid-7, 14, 15, 16, 20-penta-ol-3-oic acid, respectively, and are a novel carbon skelton. All of the fifteen alkaloids were subjected to in vitro antifungal assays, which showed that the verazine- (veramitaline, stenophylline B, stenophylline B-3-O-b-D-glucopyranoside, veramiline-3-O-b-D glucopyranoside) and jerveratrum- type (jervine, jervine-3-O-b-D-glucopyranoside) alkaloids exhibited strong antifungal activities against the phytopathogenic fungus Phytophthora capisis with MICs of 160, 120, 160, 80, 80 and 120mg·L21, respectively. Furthermore, the verazine-type alkaloids stenophylline B, stenophylline B 3-O-b-D-glucopyranoside and veramiline 3-O-b-D-glucopyranoside were shown to also inhibit the growth of another fungal phytopathogen Rhizoctonia cerealis with MICs of 160, 120 and 120mg mL21. The MICs of triadimefon (an antifungal agrochemical used herein as a positive control) against P. capisis and R. cerealis were 120 and 80mg mL21, respectively. A preliminary structure–activity relationship regarding these alkaloids has been formulated.

A new lupane type triterpenic acid, pulsatillic acid, and two new lupane type triterpenoid glycosides, pulsatiUoside A and B, along with the known 23-hydroxybetulinic acid were isolated from the roots of Pulsatilla chinensis. Their structures were characterized as 3-oxo-23-hydroxy-lup-20(29)-en-28-oic acid, 3fl, 23-dihydroxy-lup-20(29)-en-28-oic acid 3-O-a-L-arabinopyranoside and 3/3, 23-dihydroxy-lup-20(29)-en-28-oic acid 28-0-/3-0- glucopyranosyl-(1-6)-/3-o-glucopyranoside on the basis of hydrolysis and spectral evidence including two-dimensional relay HOHAHA, one-dimensional multiple relay COSY and ROESY NMR techniques. Pulsatillic acid exhibited cytotoxic activities against P-388, Lewis lung carcinoma and human large-cell lung carcinoma.

Six oleanane-type saponins, along with two known triterpene saponins, were isolated from the leaves of Gymnema sylvestre. The structures of the oleanane triterpene glycosides were characterized as longispinogenin 3-O-b-D-glucuronopyranoside, 21b-benzoylsitakisogenin 3-O-b-D-glucuronopyranoside, 3-O-b-D-glucopyranosyl(146)-b-D-glucopyranosyl oleanolic acid 28-O-b-D- glucopyranosyl ester, oleanolic acid 3-O-b-D-xylopyranosyl(146)-b-D-glucopyranosyl(146)-b-D-glucopyranoside, 3-O-b-D- xylopyranosyl(146)-b-D-glucopyranosyl(146)-b-D-glucopyranosyl oleanolic acid 28-O-b-D-glucopyranosyl ester and 3-O-b-D- glucopyranosyl(146)-b-D-glucopyranosyl oleanolic acid 28-b-D-glucopyranosyl(146)-b-D-glucopyranosyl ester on the basis of hydrolysis and spectral evidence, including 1D- and 2D-NMR (TOCSY, ROESY, HMQC and HMBC) and FABMS analyses. 72000 Elsevier Science Ltd. All rights reserved.

Three new oleanane-type triterpene glycosides (1-3), along with the sodium salt of alternoside II (4), were isolated from an ethanol extract of the leaves of Gymnema sylvestre. The structures of these new saponins were identified as 21, -O-benzoylsitakisogenin 3-O-, -D-glucopyranosyl(1f3)-, -D-glucuronopyranoside (1), the potassium salt of longispinogenin 3-O-‚-D-glucopyranosyl(1f3)-,-D-glucuronopyranoside (2), and the potassium salt of 29-hydroxylongispinogenin 3-O-,-D-glucopyranosyl(1f3)-,-D glucuronopyranoside (3). The aglycon of 3, gymnemagenol (3a), was characterized as 3., 16‚, 28, 29-tetrahydroxyolean-12-ene. Structure elucidation was accomplished by interpretation of NMR (DQF-COSY, HMQC, and HMBC) results, FABMS, and hydrolysis. Saponin 1 and the sodium salt of alternoside II (4) exhibited antisweet activity.