Pei Lin Wu

New constituents and antiplatelet aggregation and anti-HIV principles of Artemisia capillaris

Five new constituents including a flavonoid, artemisidin A (1), and four coumarins, artemicapins A (2), B (3), C (4) and D (5), together with 70 known compounds (6-75), have been isolated and characterized from the aerial part of Artemisia capillaris. The structures of these compounds were determined from spectral analyses and/or chemical evidence. Among them, 15 compounds (3, 6, 10, 18. 30-32, 38-41, 44, 45, 51, and 55) showed antiplatelet aggregation activity and three compounds (10, 17, and 51) demonstrated significant activity against HIV replication in H9 lymphocytic cells.

Carbazole alkaloids from Clausena excavata and their biological activity

Five new carbazole alkaloids, clausines B, E, H, I and K, as well as 22 known compounds, were isolated from the stem bark of Clausena excavata. The structures were established from spectral data and chemical transformation. These compounds showed significant inhibition of rabbit platelet aggregation and caused vasocontraction. The crude methanol extract, partitioned layers and chromatographic fractions revealed the presence of promotive and inhibitive constituents, simultaneously. These results might explain the philosophy of use in Chinese medicine, in that the dose and content variation in a prescription produced different, promotive or inhibitive, effects on therapy.

Alkaloidal and other constituents from the root bark of Clausena excavata

Ten new carbazole alkaloids, clausine-M, -N, -O, -P, -Q, -R, -S, -U, -V and clausenatine-A, together with 39 known compounds were isolated and identified from the acetone extract of the root bark of Clausena excavata. Their structures have been elucidated by spectroscopic analyses. This is the first report of a decarboxylated carbazole alkaloid from a natural source. The presence of a C23-skeleton carbazole alkaloid in a plant of Clausena genus is also reported for the first time.

Monoterpene glycosides from Paeonia suffruticosa

Abstract Six new monoterpene glycosides, namely mudanpioside-A to -F, were isolated as minor components from and ethanol extract of the root cortex of Paeonia suffruticosa . Their structures have been established on the basis of spectral evidence. In addition, five known glycosides, paeoniflorin, oxypaeoniflorin, benzoylpaeoniflorin, benzoyloxypaeoniflorin and apiopaeonoside, were also isolated and characterized.

The heartwood constituents of Tetradium glabrifolium

Three new compounds, evomeliaefolin, evofolin-A and -B, and 43 known compounds were isolated from the heartwood of Tetradium glabrifolium. Their structures were elucidated by spectral analyses. The existence of six benzo[c]phenanthridine alkaloids further supported that Tetradium is closely allied to Zanthoxylum, Toddalia, Phellodendron and Fagaropsis.

Rhinacanthin-Q, a naphthoquinone from Rhinacanthus nasutus and its biological activity

The continuing investigation of the root of Rhinacanthus nasutus afforded a 1,4-naphthoquinone ester, rhinacanthin-Q, accompanied by twenty-four known compounds. The structure was elucidated on the basis of spectroscopic analyses. The cytotoxicity and antiplatelet effect of this compound was also discussed.

Two coumarins from the root bark of Clausena excavata

Two new pyrano-coumarins, claucavatin-A and -B, together with eight known coumarins and two known flavonoids were isolated and identified from the acetone extract of the root bark of Clausena excavata. Their structures were elucidated by the spectroscopic analyses.

Carbazole-pyranocoumarin dimer and binary carbazole alkaloid from Clausena excavata

Abstract Examination of the extract from the stem bark and root bark of Clausena excavata , a binary carbazole alkaloid, clausenamine-A ( 1 ), and a carbazole-pyranocoumarin dimer, carbazomarin-A ( 2 ), were isolated, respectively. Their structures were elucidated by spectroscopic analyses.

Phenanthroindolizidine Alkaloids and Their Cytotoxicity from the Leaves of Ficus septica

Phenanthroindolizidine N-Oxide, ficuseptine-A (1), together with eighteen known compounds was isolated from the leaves of Ficus septica. The structures of these compounds were elucidated by spectroscopic analysis. Among them, phenanthroindolizidines, ficuseptine (1), (+)-tylophorine (4) and a mixture of (+)-tylocrebrine (5) and (+)-isotylocrebrine (6), exhibited strong cytotoxic activity against two human cancer cell lines, NUGC and HONE-1.

Carbazole alkaloids from stem bark of Clausena excavata

Abstract Four new carbazole alkaloids, clausines A, C, G and J were identified as 3-formyl-2-hydroxy-8-methoxycarbazole 3-carbomethoxy-7-methoxycarbazole, 3-carbomethoxy-1-hydroxy-6-methoxycarbazole and 3-formyl-1, 7-dihydroxy-6-methoxycarbazole, respectively, from a methanol extract of the stem bark of Clausena excavata . Structures were established by spectroscopic analyses.