Search

Two new compounds, 11,11′-dimer of scopoletin ( 1 ) and 11- O - β -glucopyranosylhamaudol ( 2 ), together with seven known compounds were isolated and identified from the whole grass of Cicuta virosa . The chemical structures of the isolated compounds were elucidated using different spectroscopic methods. In addition, the chemical constituents were evaluated for multidrug resistance reversing activity towards doxorubicin-resistant K562/A02 cells. Compounds 1 , 8 , and 9 were endowed with remarkable MDR reversing effects.

isolation, structure determination and cytotoxicity of three new metabolites, asperfumigatin (I), isochaetominine (II), and 8-O-methylasterric acid (III) along with nineteen known metabolites

Podoimbricatin A (I) and podoimbricatin B (II) are isolated together with four previously reported diterpenoids and a cyclic peptide.

isolation, structure elucidation and anticancer activity of two new stigmastane-type steroids (Ia) and (Ib)

Five new ring A-seco triterpenoids (I)—(IV) are isolated along with a known structurally related compound from twigs and leaves of the title plant.

isolation, structure elucidation and evaluation of antioxidant and cytoprotective activities of 17 flavonoids including the new flavonoids (I) and (II), preliminary structure—activity relationships

Scaparvin A (I) is isolated together with the analogues scaparvin B (IIa), C (IIb), D (IIc) and E (III).

A new nonsteroidal antiandrogenic pharmacophore has been discovered using cell-based cotransfection assays with human androgen receptor (hAR). This series of AR antagonists is structurally characterized by a linear tricyclic 1,2-dihydropyridono[5,6-g]quinoline core. Analogues inhibit AR-mediated reporter gene expression and bind to AR as potently as or better than any known AR antagonists. Several analogues also showed excellent in vivo activity in classic rodent models of AR antagonism, inhibiting growth of rat ventral prostate and seminal vesicles, without accompanying increases in serum gonadotropin and testosterone levels, as is seen with other AR antagonists. Investigations of structure−activity relationships surrounding this pharmacophore resulted in molecules with complete specificity for AR, antagonist activity on an AR mutant commonly observed in prostate cancer patients, and improved in vivo efficacy. Molecules based on this series of compounds have the potential to provide unique and effective ...

Natural stilbenes have been a hot research topic due to their intricate structures and diverse biological activities. Although their molecular backbone consists only of 1,2-diphenylethylene units, stilbenes show an enormous diversity with regard to the different units present, the degree of polymerisation, and the pattern of oligomer construction. From January 1995 to the end of 2008, more than 400 new naturally occurring stilbenes were isolated and identified, and this review focuses on their structural diversity, distribution, and bioactivity.

Three novel fernane-type triterpenoids, lobarialides A-C (1-3, resp.), together with two known ones were isolated by antifungal bioassay-guided fractionation of the lichen Lobaria kurokawae. Their structures including configurations were established on the basis of extensive spectroscopic analyses, and that of 1 was confirmed by a single-crystal X-ray diffraction analysis. Antifungal tests of the five triterpenoids showed that the activity increased with the increment of the number of COO groups.

Two novel rearranged oleanane-type triterpenes, dysoxyhainanin A (1) possessing a unique 1,3-cyclo-2,3-seco A ring with a formamido-containing appendage and dysoxyhainanin B (2) featuring an unprecedented 1,2-dinor-3,10:9,10-bisseco skeleton, were isolated from Dysoxylum hainanense. Dysoxyhainanin A (1) exhibited significant antibacterial activity against Gram-positive bacteria.

Three new triterpenoids, turrapubesols A–C (1–3), and one new sesquiterpenoid, 1α,4α-dihydroxyeudesman-11-ene (4), along with 12 known terpenoids were isolated from Turraea pubescens. The structures of the terpenoids were established on the basis of extensive spectroscopic analyses and by a chemical transformation. The previous assignment of the NMR data for guaidiol (5) was corrected. Some of the triterpenoids exhibited cytotoxicity against the P-388 cell line.

Walsucochins A (1) and B (2) with an unprecedented skeleton were isolated from Walsura cochinchinensis. Their structures including absolute configuration were elucidated by spectral methods. A biosynthetic pathway of 1 and 2 was postulated. Both 1 and 2 exhibited significant cell protecting activities against H2O2-induced PC12 cell damage.

Seventeen Daphniphyllum alkaloids, including two new pentacyclic alkaloids, yuzuric acid (1) and daphnezomic acid (2), and 15 known ones, were isolated from the fruits of Daphniphyllum oldhamii. The structures and configuration of the two new alkaloids were determined on the basis of spectroscopic methods, especially 2D NMR techniques.

Three new alkaloids, N-hydroxypaxdaphnine B (1), 21-O-acetylpaxdaphnine B (2), and methyl 17-hydroxyhomodaphniphyllate (3), were isolated from the fresh fruits of Daphniphyllum macropodum, together with six known alkaloids. Their structures were established on the basis of extensive spectroscopic and mass-spectrometric analyses in combination with chemical transformations.

Eight new ring B-seco limonoids, turrapubesic acids A–C (1–3) and turrapubesins C–G (4–8), along with turraflorin E and isoazadironolide were isolated from the twigs and leaves of Turraea pubescens. Turrapubesic acids A–C (1–3) are a group of ring B-seco limonoid 17-carboxylic acids with a new C23 skeleton, and turrapubesin C (4) incorporates an unprecedented 1,30-oxygen bridge. The structures including absolute stereochemistry of 1–8 were established on the basis of extensive NMR spectroscopic analysis and CD study. The cytotoxicity of the isolates against the P-388 and A-549 cells was evaluated.