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1.
J Nat Prod ; 66(9): 1166-70, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14510590

RESUMEN

A new butenylflavanone, (2S)-5-hydroxy-7-methoxy-8-[(E)-3-oxo-1-butenyl]flavanone (1), and a new rotenoid, 4',5'-dihydro-11,5'-dihydroxy-4'-methoxytephrosin (2), as well as three active flavonoids of previously known structure, isoliquiritigenin (3), genistein (4), and chrysoeriol (5), along with nine known inactive compounds, alpha-toxicarol (6), sumatrol, 6a,12a-dehydro-alpha-toxicarol, 11-hydroxytephrosin, obovatin, marmesin, lupenone, benzyl benzoate, and benzyl trans-cinnamate, were isolated from an ethyl acetate-soluble extract of the stems of Tephrosia toxicaria, using a bioassay based on the induction of quinone reductase (QR) in cultured Hepa 1c1c7 mouse hepatoma cells to monitor chromatographic fractionation. The structures of compounds 1 and 2 were elucidated by spectroscopic data interpretation. All isolates were evaluated for their potential cancer chemopreventive properties utilizing an in vitro assay to determine quinone reductase induction. Selected compounds were tested in a mouse mammary organ culture assay to evaluate the inhibition of 7,12-dimethylbenz[a]anthracene (DMBA)-induced preneoplastic lesions.


Asunto(s)
Anticarcinógenos/aislamiento & purificación , Cromonas/aislamiento & purificación , Flavonoides/aislamiento & purificación , Compuestos Heterocíclicos de 4 o más Anillos/aislamiento & purificación , Plantas Medicinales/química , Tephrosia/química , Animales , Anticarcinógenos/química , Anticarcinógenos/farmacología , Carcinoma Hepatocelular , Cromonas/química , Cromonas/farmacología , Flavonoides/química , Flavonoides/farmacología , Compuestos Heterocíclicos de 4 o más Anillos/química , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Neoplasias Mamarias Experimentales , Ratones , Estructura Molecular , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Perú , Tallos de la Planta/química , Estereoisomerismo , Células Tumorales Cultivadas/efectos de los fármacos
2.
J Nat Prod ; 66(5): 583-7, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12762787

RESUMEN

A new cassane diterpene, dipteryxic acid (1), and a new isoflavonolignan, 5-methoxyxanthocercin A (2), as well as four known active compounds, isoliquiritigenin (3), 6,4'-dihydroxy-3'-methoxyaurone (4), sulfuretin (5), and (+/-)-balanophonin (6), and five known inactive compounds, butin, eriodictyol, 7-hydroxychromone, 7,3'-dihydroxy-8,4'-dimethoxyisoflavone, and (-)-lariciresinol, were isolated from an ethyl acetate-soluble extract of the seeds of Dipteryx odorata, using a bioassay based on the induction of quinone reductase (QR) in cultured Hepa 1c1c7 mouse hepatoma cells to monitor chromatographic fractionation. The structures of compounds 1 and 2 were elucidated by spectroscopic data interpretation. Single-crystal X-ray diffraction analysis was used to confirm the relative stereochemistry of compound 1. Selected compounds (3-5) were evaluated in a mouse mammary organ culture assay, with isoliquiritigenin (3) found to exhibit 76% inhibition at a dose of 10 microg/mL.


Asunto(s)
Anticarcinógenos/aislamiento & purificación , Diterpenos/aislamiento & purificación , Fabaceae/química , Isoflavonas/aislamiento & purificación , Lignanos/aislamiento & purificación , Animales , Anticarcinógenos/química , Anticarcinógenos/farmacología , Cristalografía por Rayos X , Modelos Animales de Enfermedad , Diterpenos/química , Diterpenos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Inducción Enzimática , Concentración 50 Inhibidora , Isoflavonas/química , Isoflavonas/farmacología , Lignanos/química , Lignanos/farmacología , Glándulas Mamarias Animales/efectos de los fármacos , Ratones , Conformación Molecular , Estructura Molecular , NAD(P)H Deshidrogenasa (Quinona)/biosíntesis , Resonancia Magnética Nuclear Biomolecular , Técnicas de Cultivo de Órganos , Perú , Semillas/química , Estereoisomerismo , Células Tumorales Cultivadas/efectos de los fármacos
3.
J Org Chem ; 68(6): 2350-61, 2003 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-12636402

RESUMEN

Activity-monitored fractionation of a CHCl(3)-soluble extract of Deprea subtriflora using a quinone reductase induction assay led to the purification of subtrifloralactones A-J (1-10), 10 novel C-18 norwithanolides based on a new C(27) skeleton. These compounds were characterized by spectroscopic and chemical studies, and single-crystal X-ray diffraction analysis was used to confirm the structures of 1 and 4. Compounds 1-10 were evaluated for their cancer chemopreventive activity in terms of their ability to induce quinone reductase activity with cultured murine hepatoma cells, and compounds 1 and 6 were found to be highly effective.


Asunto(s)
Lactonas/aislamiento & purificación , Plantas Medicinales/química , Solanaceae/química , Animales , Anticarcinógenos , Carcinoma Hepatocelular , Cristalografía por Rayos X , Ensayos de Selección de Medicamentos Antitumorales , Lactonas/química , Lactonas/farmacología , Ratones , Conformación Molecular , Estructura Molecular , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Resonancia Magnética Nuclear Biomolecular , Perú , Células Tumorales Cultivadas/efectos de los fármacos
4.
J Nat Prod ; 65(11): 1616-20, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12444686

RESUMEN

Three new prenylated dihydrochalcones, (+/-)-nicolaioidesins A, B, and C (1-3), as well as a new natural product, 5-styrylfuran-2-carboxylic acid methyl ester (4), along with four known compounds, 2'-hydroxy-4',6'-dimethoxychalcone (5), (+/-)-5-hydroxy-7-methoxyflavanone (6), (+/-)-5-hydroxy-7,4'-dimethoxyflavanone, and panduratin A, were isolated from the roots of Renealmia nicolaioides, using a bioassay to determine the induction of quinone reductase (QR) activity with cultured Hepa lclc7 mouse hepatoma cells. Among these isolates, 5 and 6 induced QR activity, with observed concentrations to double activity (CD) values of 1.7 and 0.9 microg/mL, respectively, while the other constituents were not regarded as being active (CD >10 microg/mL). The chemical structures of 1-4 were elucidated by spectroscopic methods. A biogenetic pathway for the formation of (+/-)-nicolaioidins A-C (1-3) is proposed.


Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Chalcona/aislamiento & purificación , Plantas Medicinales/química , Zingiberaceae/química , Animales , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Carcinoma Hepatocelular , Chalcona/análogos & derivados , Chalcona/química , Chalcona/farmacología , Chalconas , Cromatografía Líquida de Alta Presión , Ensayos de Selección de Medicamentos Antitumorales , Concentración 50 Inhibidora , Ratones , Conformación Molecular , Estructura Molecular , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Perú , Raíces de Plantas/química , Relación Estructura-Actividad , Células Tumorales Cultivadas/efectos de los fármacos
5.
J Nat Prod ; 65(4): 532-6, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11975495

RESUMEN

Activity-guided fractionation of an ethyl acetate extract of the aerial parts of Tithonia diversifolia, using an antiproliferation bioassay performed with human colon cancer (Col2) cells, led to the isolation of three new sesquiterpenoids, 2alpha-hydroxytirotundin (1), tithofolinolide (2), and 3alpha-acetoxydiversifolol (3), along with eight known sesquiterpene lactones, 3beta-acetoxy-8beta-isobutyryloxyreynosin (4), tagitinin C (5), 1beta,2alpha-epoxytagitinin C (6), 4alpha,10alpha-dihydroxy-3-oxo-8beta-isobutyryloxyguaia-11(13)-en-12,6alpha-olide (7), 3alpha-acetoxy-4alpha-hydroxy-11(13)-eudesmen-12-oic acid methyl ester, 17,20-dihydroxygeranylnerol, tagitinin A, and tirotundin. These isolates were evaluated for their potential as cancer chemopreventive agents, by measuring antiproliferative activity in Col2 cells and induction of cellular differentiation in human promyelocytic leukemia (HL-60) cells. Selected compounds were then investigated for their ability to inhibit 7,12-dimethylbenz[a]anthracene-induced preneoplastic lesions in a mouse mammary organ culture assay. Among these isolates, 5 and 6 showed significant antiproliferative activity, 2, 4, and 7 induced HL-60 cellular differentiation, and 4 significantly inhibited (63.0% at 10 microg/mL) lesion formation in the mouse mammary organ culture assay. The chemical structures of 1-3 were elucidated by spectroscopic analysis. The absolute configurations of 1 and 2 were determined by Mosher ester methodology.


Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Asteraceae/química , Lactonas/aislamiento & purificación , Plantas Medicinales/química , Sesquiterpenos/aislamiento & purificación , Animales , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Benzo(a)Antracenos/farmacología , Cromatografía Líquida de Alta Presión , Humanos , Lactonas/química , Lactonas/farmacología , Leucemia Mieloide , Neoplasias Mamarias Experimentales/inducido químicamente , Ratones , Ratones Endogámicos BALB C , Conformación Molecular , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Puerto Rico , Sesquiterpenos/química , Sesquiterpenos/farmacología
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