Showing papers by "Jiangong Shi published in 2009"

Chemical constituents of the bark of Machilus wangchiana and their biological activities.

Abstract: Eleven new metabolites, butanolides 1-6, lignan derivatives 7-9, sesquiterpene 10, and 3',4'-seco-flavane derivative 11, have been isolated from an ethanol extract of Machilus wangchiana. Twenty known compounds, including ginkgolides A and B (16 and 17), were also isolated. Their structures and absolute configurations were determined by spectroscopic and chemical methods. Compounds 7, 8a, 8b, 9, 11, (+)-guaiacin (12), meso-dihydroguaiaretic acid (13), and hamabiwalactone A (15) showed potent in vitro activities against the release of beta-glucuronidase in rat polymorphonuclear leukocytes (PMNs) induced by platelet-activating factor (PAF), with 42.5-75.6% inhibition at 10(-5) M. Compounds 8, 8a, 8b, 9, and 11 reduced dl-galactosamine (GalN)-induced hepatocyte (WB-F344 cells) damage with 39.4 +/- 6.3% to 53.6 +/- 3.5% inhibition at 10(-4) M. Isomahubannolide-23 (14) was cytotoxic against human stomach cancer (BGC-823) and ovarian cancer (A2780) cell lines, with IC(50) values of 0.13 and 2.66 muM, respectively.

Chemical Constituents of the Roots of Euphorbia micractina.

Abstract: Nine minor new tirucallane (1−7) and euphane (8 and 9) triterpenoids including five hydroperoxides, together with 18 known compounds, have been isolated from an ethanolic extract of the roots of Euphorbia micractina. Their structures including absolute configurations were elucidated by spectroscopic and chemical analysis. In the in vitro assays, betulin (10) showed a selective cytotoxic activity against A2780 ovarian cells with an IC50 value of 6.1 μM and inhibitory activity against protein tyrosine phosphatase 1B (PTP1B) with an IC50 value of 15.3 μM. Jolkinol B (11) showed a potent activity against HIV-1 replication with an IC50 value of 12.6 μM. However, compounds 1−9 and the other known compounds were inactive in the three assays used.

Chemical constituents of Heteroplexis micocephala.

Abstract: Eleven new compounds including two sesquiterpenes with an unusual 2,2,5,9-tetramethylbicyclo[6.3.0]undecane carbon skeleton (1 and 2), five phytane-type diterpene dilactones (3-7), an ent-clerodane diterpene dilactone (8), and three phenylpropenol esters (9-11), together with a diacylphenol (12) and 38 known compounds, have been isolated from an ethanolic extract of Heteroplexis micocephala. Their structures including absolute configurations were elucidated by spectroscopic and chemical analyses. In the in vitro assays, compound 6 showed a selective cytotoxic activity against A2780 with an IC(50) value of 4.37 microM, while sinapyl diangelate (13) showed a potent activity inhibiting HIV-1 replication with an IC(50) value of 4.04 microM.

N6-substituted adenosine derivatives and n6-substituted adenine derivatives and uses thereof

Abstract: The present invention provides N6-substituted adenosine derivatives, N6-substituted adenine derivatives, manufacturing methods thereof, a pharmaceutical composition comprising said compounds above, and the uses of these compounds in manufacture of medicaments and health care products for sedative, hypnotics, anti-convulsion, anti-epilepsy, anti-Parkinson's disease, preventing and treating dementia.

Cytotoxic triterpenoid glycosides from the roots of Gordonia chrysandra

Abstract: Eight new oleanane triterpenoid glycosides, gordonosides A-H (1-8), were isolated from a 50% EtOH extract of the roots of Gordonia chrysandra. Their structures were determined by spectroscopic analysis, including 1D and 2D NMR and ESIMS, and by chemical methods. Among these substances, compounds 1, 3, 5, and 6 exhibited cytotoxic activity against several human cancer cell lines, with 3 being the most potent.

A novel bromophenol from marine red alga Symphyocladia latiuscula

Abstract: 2,3,6-Tribromo-4,5-dihydroxybenzyl ethyl ether (1), a new bromophenol, was isolated from the ethanol extract of marine red alga Symphyocladia latiuscula, with a known compound, 2,3,6-tribromo-4,5-dihydroxybenzyl methyl ether ( 2). Their structures were elucidated by spectroscopic analysis, including high-resolution mass spectroscopy, and 1 and 2-dimensional NMR techniques. Compounds 1 and 2 showed inhibitory activity against Staphyloccocus aureus with IC(50) 102 and 50 mu g/mL, respectively.

Bioactive sterols from red alga Acanthophora spicifera boergesen

Abstract: OBJECTIVE To study the chemical constituents of the red alga Acanthophora spicifera boergesen aiming at searching for bioactive leading compounds. METHOD Compounds were isolated by various chromatographic techniques including column chromatography over normal phase silica gel and Sephadex LH-20 gel and reverse phase HPLC as well as recrystallization. Their structures were determined by spectroscopic methods including IR, MS, 1D and 2D NMR techniques. MTT method was used for testing cytotoxicity of compounds against human cancer cell lines HCT-8, Bel-7402, BGC-823, A549 and HELA. Their inhibition against proliferation of dog vascular smooth muscle cells was also screened by MTT assay. RESULT Six sterols were isolated from the ethanolic extract of the red alga Acanthophora spicifera. Their structures were identified as 6-hydroxycholest-4-ene-3-one (1), cholest-4-ene-3, 6-dione (2), cholest-5-ene-3 beta-ol (3), 5 alpha-cholestane-3, 6-dione (4), beta-sitosterol (5) and saringosterol (6). CONCLUSION Compounds 1-3 and 5 were obtained from this genus for the first time. Compounds 1, 2 and 4 showed moderate cytotoxic activity against human cancer cell lines.