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.

Two new stenine-type alkaloids, neotuberostemonol (3) and neotuberostemoninol (4), along with the known compound neotuberostemonine (2), were isolated from Stemona tuberosa Lour. Their structures were characterized by X-ray crystallography in combination with spectroscopic methods, and their absolute configurations were inferred from the known configuration of tuberostemonine (1). In the crystalline state, weak C-H O hydrogen bonds play an important role in the molecular packing of 3 and 4. q 2002 Elsevier Science Ltd. All rights reserved.

Three isoquinoline alkaloids and an isoindole alkaloid, along with eight known compounds, were isolated from the roots of Menispermum dauricum (Menispermacese). The alkaloids were characterized as 7-hydroxy-6-methoxy-1(2H)-isoquinolinone, 6,7- dimethoxy-N-methyl-3,4-dioxo-1(2H)-isoquinolinone, 1-(4-hydroxybenzoyl)-7-hydroxy-6-methoxy-isoquinoline and 6-hydroxy-5-methoxy-N-methylphthalimide, on the basis of spectral evidence including 1D-and 2D-NMR and MS analyses.

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.

Three new cycloDentanold monoterpenes namecl piscrocins A (1) B (2)antl (3) were lsolateclcom the roots of Pic~orhnd sctophulariiflora (scrophulariaceae). The structures ofthese new compounds were establishecl by 1D antl 2D NMR spectroscopic techniques (HHCOSY, HMQC, HMBC, antl NOESY) In combination with X ray clystallographic analysis