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1.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 10): o2564-5, 2009 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-21578003

RESUMO

THE TITLE STRUCTURE (SYSTEMATIC NAME: 9-hydroxy-methyl-3,6-di-methyl-3-methyl-ene-2,7-dioxo-3,3a,4,5,9a,9b-hexa-hydro-azu-leno[4,5-b]furan-4-yl acetate hemihydrate), C(17)H(20)O(6)·0.5H(2)O, from Lactuca floridana, has two independent sesquiterpene lactone mol-ecules in the asymmetric unit. Both have their seven-membered rings in the chair conformation. In the crystal, the OH groups and the water mol-ecule form classical O-H⋯O hydrogen bonds with O⋯O distances in the range 2.6750 (17)-2.8160 (18) Å.

2.
Cancer Chemother Pharmacol ; 60(1): 35-43, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17149609

RESUMO

PURPOSE: Nuclear factor-kappaB (NF-kappaB) plays a crucial role in the regulation of inflammatory processes, cell proliferation, and apoptosis. Blocking NF-kappaB signaling may represent a therapeutic strategy in cancer and inflammation therapy. The aim of this study was to investigate the effects of sesquiterpenes isolated from Asteraceae, namely melampolides (enhydrin, tetraludin A) and repandolides (repandins A, B, D and E) on the activation of NF-kappaB, cell growth of cancer cells, cell cycle progression and apoptosis. In addition, their effects on the activity of cyclooxygenase-2 (COX-2) enzyme were also evaluated. METHODS: Cell-based reporter gene assay was conducted in SW1353 cells. COX-2 enzyme activity and cell growth inhibition was determined by enzyme immunoassay and MTT assay respectively. Cell cycle analysis was carried out by flow cytometry and apoptosis was observed by DAPI staining assay. RESULTS: In SW1353 cells, transcription mediated by NF-kappaB was inhibited by enhydrin, tetraludin A and repandins A, B, D and E, while Sp-1 mediated transcription was not affected. COX-2 enzyme activity was inhibited by enhydrin, repandin A and E, but not by tetraludin A, repandin B and D. These compounds were effective in inhibiting the growth of a panel of human tumor cell lines in a concentration-dependent manner. Cell cycle analysis and DAPI staining indicated cell cycle arrest in G(2)/M phase and induction of apoptosis. CONCLUSIONS: Enhydrin, tetraludin A and repandins A, B, D and E inhibited tumor cell growth and induced cell cycle arrest and apoptosis. These effects may be related to inhibition of NF-B activation.


Assuntos
Apoptose/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Sesquiterpenos/farmacologia , Transcrição Gênica/efeitos dos fármacos , Asteraceae/química , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/isolamento & purificação , Inibidores de Ciclo-Oxigenase 2/farmacologia , Relação Dose-Resposta a Droga , Fase G2/efeitos dos fármacos , Células HL-60 , Humanos , Concentração Inibidora 50 , Lactonas/química , Lactonas/isolamento & purificação , Lactonas/farmacologia , Luciferases/genética , Luciferases/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Microscopia de Fluorescência , Estrutura Molecular , NF-kappa B/genética , NF-kappa B/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Fator de Transcrição Sp1/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
3.
Antiviral Res ; 68(3): 163-72, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16280176

RESUMO

A novel low molecular weight compound, CJ 4-16-4, isolated from ethnobotanicals using bioassay-guided fractionation, was found to be a potent inhibitor of respiratory syncytial virus (RSV) in vitro and in vivo. In vitro, a very low micromolar efficacious dose was obtained against at least four of subtype A (RSV-Long, RSV A2, and RSV A6 57754) and one of subtype B (Washington) RSV strains without seeing any significant cytotoxicity to Hep-2, MDCK or Vero cell lines. The drug inhibits growth of RSV in Hep-2 cells maintained in tissue culture at a very low concentration (approximately 0.07 microM) with cell toxicity >400 microM (TI>5880). In a cotton rat model of RSV infection, the drug was able to reduce viral titers by approximately 1 log at dose 12.5 and 25 mg/kg/day, and by >2 log at 100 mg/kg/day. This antiviral activity was specific as influenza A and B and herpes simplex 1 and 2 viruses were not inhibited. The results obtained indicate that CJ 4-16-4 warrants clinical development.


Assuntos
Antivirais/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Plantas Medicinais/química , Ácido Quínico/análogos & derivados , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Antivirais/isolamento & purificação , Técnicas de Cultura de Células , Ácido Quínico/isolamento & purificação , Ácido Quínico/farmacologia , Infecções por Vírus Respiratório Sincicial/tratamento farmacológico
4.
Life Sci ; 78(5): 485-94, 2005 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-16243360

RESUMO

The challenge of discovering new, urgently needed anti-TB drugs from natural sources requires a truly interdisciplinary research. Cutting-edge mycobacteriology and innovative natural products chemistry tools have to be developed and employed in tandem, in order to meet these demands. The present review provides cross-linkage to the most recent literature on anti-TB active natural products and summarizes the recent developments in both fields and their potential to impact the early steps of the TB drug discovery process.


Assuntos
Antituberculosos/farmacologia , Produtos Biológicos/farmacologia , Tuberculose/tratamento farmacológico , Animais , Antituberculosos/química , Antituberculosos/uso terapêutico , Antituberculosos/toxicidade , Bioensaio , Produtos Biológicos/química , Produtos Biológicos/uso terapêutico , Produtos Biológicos/toxicidade , Humanos , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/microbiologia
5.
Nat Prod Commun ; 5(5): 685-94, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20521531

RESUMO

Chemical constituents of the perennial shrub Calamintha ashei have been characterized as part of our investigation of the allelopathic properties of this plant. Besides the known monoterpenes, (+)-evodone, (-)-calaminthone and (+)-desacetylcalaminthone, fresh aerial parts of C. ashei provided six new menthofurans, two new germacrane sesquiterpenes, and the six, known flavonoids: 5-desmethoxynobiletin, 5-hydroxy-6,7,8,4'-tetramethoxyflavone, 5,4'-dihydroxy-6,7,8,3'-tetramethoxyflavone, thymonin, 5,4'-dihydroxy-6,7-dimethoxyflavone and 6-hydroxy-7,3'-dimethoxyluteolin. The structures of the new compounds were elucidated by spectroscopic methods and comparison of their 1H NMR spectra with those of structurally related compounds. The molecular structures of (+)-evodone, 5-desmethoxynobiletin (5-hydroxy-6,7,8,3',4'-pentamethoxyflavone) and the triacetate of thymonin (7,8,3'-trimethoxy-5,6,4'-triacetoxyflavone), were determined by single crystal X-ray diffraction. Saturated aqueous solutions of menthofuran, (+)-evodone, (-)-calaminthone, (+)-desacetylcalaminthone, 4alpha,5beta-diacetoxymenthofuran, as well as mixtures of (+)-evodone and (+)-desacetylcalaminthone inhibited the germination and root growth of Schizachyrium scoparium and Leptochloa dubia, two native Florida sandhill grasses, as well as Lactuca sativa. (+)-Evodone and (+)-desacetylcalaminthone were the most active. 5-Hydroxy-6,7,8,3',4'-pentamethoxyflavone and 5,4'-dihydroxy-6,7,8,3'-tetramethoxyflavone and mixtures of the two flavonoids in aqueous as well as in saturated aqueous solutions ofursolic acid were tested on the same species, but showed no significant activity.


Assuntos
Flavonoides/isolamento & purificação , Furanos/isolamento & purificação , Lamiaceae/química , Componentes Aéreos da Planta/química , Extratos Vegetais/isolamento & purificação , Sesquiterpenos de Germacrano/isolamento & purificação , Flavonoides/química , Flavonoides/toxicidade , Florida , Furanos/química , Furanos/toxicidade , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Poaceae/efeitos dos fármacos , Poaceae/crescimento & desenvolvimento , Sesquiterpenos de Germacrano/química , Sesquiterpenos de Germacrano/toxicidade , Difração de Raios X
6.
Acta Crystallogr C ; 58(Pt 3): o131-2, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11870303

RESUMO

The title compound, stigmasta-5,22-dien-3beta-ol hemihydrate, C(29)H(48)O x 0.5H(2)O, previously thought to be the monohydrate, has two sterol molecules and one water molecule in the asymmetric unit. In both sterol molecules, the methyl group of the ethyl substituent at the end of the hydrocarbon chain is disordered over two sites. The OH group of molecule A donates a hydrogen bond to a water molecule and accepts a hydrogen bond from the OH group of molecule B. The OH group of molecule B accepts two hydrogen bonds from water molecules.


Assuntos
Estigmasterol/química , Asteraceae/química , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular
7.
Acta Crystallogr C ; 58(Pt 3): o195-8, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11870327

RESUMO

A low-temperature structure of ginkgolide A monohydrate, (1R,3S,3aS,4R,6aR,7aR,7bR,8S,10aS,11aS)-3-(1,1-dimethylethyl)-hexahydro-4,7b-dihydroxy-8-methyl-9H-1,7a-epoxymethano-1H,6aH-cyclopenta[c]furo[2,3-b]furo[3',2':3,4]cyclopenta[1,2-d]furan-5,9,12(4H)-trione monohydrate, C(20)H(24)O(9) x H(2)O, obtained from Mo K alpha data, is a factor of three more precise than the previous room-temperature determination. A refinement of the ginkgolide A monohydrate structure with Cu K alpha data has allowed the assignment of the absolute configuration of the series of compounds. Ginkgolide C sesquihydrate, (1S,2R,3S,3aS,4R,6aR,7aR,7bR,8S,10aS,11S,11aR)-3-(1,1-dimethylethyl)-hexahydro-2,4,7b,11-tetrahydroxy-8-methyl-9H-1,7a-epoxymethano-1H,6aH-cyclopenta[c]furo[2,3-b]furo[3',2':3,4]cyclopenta[1,2-d]furan-5,9,12(4H)-trione sesquihydrate, C(20)H(24)O(11) x 1.5H(2)O, has two independent diterpene molecules, both of which exhibit intramolecular hydrogen bonding between OH groups. Ginkgolide J dihydrate, (1S,2R,3S,3aS,4R,6aR,7aR,7bR,8S,10aS,11aS)-3-(1,1-dimethylethyl)-hexahydro-2,4,7b-trihydroxy-8-methyl-9H-1,7a-epoxymethano-1H,6aH-cyclopenta[c]furo[2,3-b]furo[3',2':3,4]cyclopenta[1,2-d]furan-5,9,12(4H)-trione dihydrate, C(20)H(24)O(10) x 2H(2)O, has the same basic skeleton as the other ginkgolides, with its three OH groups having the same configurations as those in ginkgolide C. The conformations of the six five-membered rings are quite similar across ginkgolides A-C and J, except for the A and F rings of ginkgolide A.


Assuntos
Diterpenos , Ginkgo biloba/química , Lactonas/química , Cristalografia por Raios X , Ginkgolídeos , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Modelos Moleculares
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