Three new cucurbitane triterpenoids 1-3 and one new steroidal glycoside 4, were isolated together with ten known compounds from Momordica charantia. The structures of new compounds were determined to be 19(R)-n-butanoxy-5 beta,19-epoxycucurbita-6,23-diene-3beta,25-diol 3-O-beta-glucopyranoside (1), 23-O-beta-allopyranosylecucurbita-5,24-dien-7… (More)
Four new triterpenoid alkaloid derivatives, buxrugulines A–D (1–4), together with four known ones (5–8), were isolated from the leaves and stems of Buxus rugulosa. The structures of compounds 1–4 were elucidated by NMR and MS spectroscopic analysis. All compounds were assayed for their cytotoxicities against HL-60, SMMC-7721, A549, MCF-7, and SW480 cells… (More)
With the tremendous amount of information available electronically, there is an increasing requirement for automatic text summarization systems. An extractive summarization method is represented. The weight of a Chinese word/phrase is computed based on its frequency, part of speech, position and length. The weight of a Chinese sentence is computed by its… (More)
Nine new pregnane alkaloids, pachysamines J-R (1-9), together with seven known ones, were isolated from Pachysandra axillaris. The chemical structures of the new alkaloids were elucidated by spectroscopic methods. All the compounds were evaluated for their inhibitory activities against HL-60, SMMC-7721, A-549, SK-BR-3, and PANC-1 cell lines. Compound 15… (More)
Three new triterpenoid alkaloids, namely buxmicrophyllines P-R (1-3), were isolated from the twigs and leaves of Buxus microphylla. Their structures were elucidated on the basis of NMR and MS spectroscopic analyses. Structurally, compounds 1-3 belong to the 9,10-cycloartane type alkaloids. In addition, compound 3 exhibited moderate cytotoxic activities in… (More)
Three new physalin steroids, physalin III (1), physalin IV (2), 3-O-methylphysalin X (3), together with five known physalins (4–8) were isolated from the 80% EtOH extract of calyces of Physalis alkekengi var. franchetii. The structures of the new compounds were revealed through 1D and 2D NMR and mass spectroscopic studies.
Two new cucurbitacins, jinfushanencins A (1) and B (2), seven new cucurbitane glycosides, jinfushanosides E-K (3–9), along with nine known analogues, were obtained from the tubers of Hemsleya penxianensis. Their structures were elucidated on the basis of extensive spectroscopic and chemical methods. Selected isolates were tested their anti-HIV-1 activities,… (More)