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Artigo Revisado por pares

Francisco Cruz, Leovigildo Quijano, F́ederico Gómez-Garibay, Tirso Ríos,

... Metabolites from the Sponge Aplysina (verongia) thionaFrancisco Cruz, Leovigildo Quijano, Federico Gómez-Garibay, and Tirso RiosCite this: ...

Tópico(s): Marine Sponges and Natural Products

1990 - American Chemical Society | Journal of Natural Products

Artigo

Catherine Navarro Cordero,

... y analizar algunos de los aportes historiograficos sobre Leovigildo, Hermenegildo y, mas particularmente, el proceso de conversion. ... nacional del reino visigodo de Toledo concebido por Leovigildo toma forma gracias a la religion bajo el ...

Tópico(s): Medieval Iberian Studies

2000 - Complutense University of Madrid | ˜'œIlu. Anejos

Artigo Revisado por pares

Antonio Arribas Palau, Fernando Ricardo Molina González, Leovigildo Sáez Pérez, Francisco de la Torre Peña, Pedro Aguayo de Hoyos, Adelaida Bravo, Ángela Suárez Márquez,

... los tambien profesores de la Universidad de Granada Leovigildo Saez, Francisco de la Torre, Pedro Aguayo, Trinidad ...

Tópico(s): Archaeology and Cultural Heritage

1983 - University of Granada | Cuadernos de Prehistoria y Arqueología de la Universidad de Granada

Artigo Revisado por pares

Leovigildo Quijano, Fernando Luis Malanco, Tirso Ríos,

Two new flavonols, eupalitin and eupatolitin were isolated from Eupatorium ligustrinum D.C. as their rhamnosides. The structure of eupalitin (II) was established as the 3,5,4′-trihydroxy-6,7dimethoxyflavone and that for eupatolitin (IX) as 3,5,3′,4′-tetrahydroxy-6,7 dimethoxyflavone. In eupalin and eupatolin a rhamnose molecule is attached at the 3 position.

Tópico(s): Natural product bioactivities and synthesis

1970 - Elsevier BV | Tetrahedron

Artigo Revisado por pares

J. Romo, T. Ríos, Leovigildo Quijano,

The structure of ligustrin a constituent of Eupatorium ligustrinum DC. has been established as a sesquiterpene lactone of the guaiane series presented by formula Ia.

Tópico(s): Natural product bioactivities and synthesis

1968 - Elsevier BV | Tetrahedron

Artigo Revisado por pares

Tirso Ríos, Leovigildo Quijano,

Tópico(s): Insect Pest Control Strategies

1969 - Elsevier BV | Tetrahedron Letters

Artigo Revisado por pares

Leovigildo Quijano, José S. Calderón, Generosa Gómez, Irma Soria, T. Ríos,

Tópico(s): Bioactive natural compounds

1980 - Elsevier BV | Phytochemistry

Artigo Revisado por pares

Leovigildo Quijano, José S. Calderón, F. Gómez, T. Ríos,

Besides agecorynin C, eupalestin and lucidin dimethyl ether, two new highly oxygenated flavones were isolated from Ageratum houstonianum. Their structures were established by spectroscopic and degradative evidence as 5, 6, 7, 8, 2′, 3′, 4′, 5′-octamethoxyflavone and 5, 6, 7, 2′, 3′, 4′, 5′-heptamethoxyflavone.

Tópico(s): Phytochemical Studies and Bioactivities

1980 - Elsevier BV | Phytochemistry

Artigo Revisado por pares

F. Gómez, Leovigildo Quijano, J. S. CALDERON, T. Ríos,

Tópico(s): Traditional and Medicinal Uses of Annonaceae

1980 - Elsevier BV | Phytochemistry

Artigo Revisado por pares

Leovigildo Quijano, José S. Calderón, Generosa Gómez, José Garduño, Tirso Ríos,

Tópico(s): Biological Activity of Diterpenoids and Biflavonoids

1980 - Elsevier BV | Phytochemistry

Artigo Revisado por pares

Leovigildo Quijano, José S. Calderón, Generosa Gómez, Coaquira Rios,

The investigation of Montanoa frutescens afforded a new sesquiterpene lactone of the germacrolide type, montafrusin, besides the known diterpenes kaurenic acid and its 15α-isovalerate.

Tópico(s): Synthetic Organic Chemistry Methods

1979 - Elsevier BV | Phytochemistry

Artigo Acesso aberto Revisado por pares

Leovigildo Quijano, Alfonso Romo de Vivar, Tirso Ríos,

Tópico(s): Plant Toxicity and Pharmacological Properties

1979 - Elsevier BV | Phytochemistry

Artigo Revisado por pares

F. Gómez, Leovigildo Quijano, José S. Calderón, Áurea Perales, T. Ríos,

Tópico(s): Natural product bioactivities and synthesis

1982 - Elsevier BV | Phytochemistry

Artigo Revisado por pares

Leovigildo Quijano, José S. Calderón, F. Gómez, T. Ríos,

Tópico(s): Phytochemical Studies and Bioactivities

1982 - Elsevier BV | Phytochemistry

Artigo Revisado por pares

F. Gómez, Leovigildo Quijano, Gustavo A. García, José S. Calderón, T. Ríos,

5,7-Dimethoxy-8-prenylflavan has been isolated and identified from aerial parts of Tephrosia madrensis.

Tópico(s): Plant chemical constituents analysis

1983 - Elsevier BV | Phytochemistry

Artigo Revisado por pares

Alfonso G. Ober, Leovigildo Quijano, Lowell E. Urbatsch, Nikolaus H. Fischer,

Chemical analysis of Calea subcordata yielded three new guaianolides, 8-epi-isobutyrylrupicolin A, 8-epi-isobutyrylrupicolin B and subcordatolide A, which represent the first guaianolide-type sesquiterpene lactones reported in the genus Calea. The structures of the new compounds were established by chemical and spectroscopic methods.

Tópico(s): Traditional and Medicinal Uses of Annonaceae

1984 - Elsevier BV | Phytochemistry

Artigo Revisado por pares

Leovigildo Quijano, Federico Gómez Galindo, José S. Calderón, Jesus López P, Tirso Ríos,

Further investigation of Montanoa tomentosa afforded two new guaianolides as well as the known pumilin and the previously isolated heliangolide zoapatanolide A. The structures were established on the basis of spectroscopic studies and chemical evidence.

Tópico(s): Traditional and Medicinal Uses of Annonaceae

1984 - Elsevier BV | Phytochemistry

Artigo Revisado por pares

Leovigildo Quijano, Nikolaus H. Fischert,

the aerial parts of Melampodium longipilum afforded two new diterpene lactones, 17-hydroxy- and 17-acetoxyacanthoaustralide, and a new sesquiterpene lactone, repandin E, besides the known melampolides enhydrin and fluctuanin.

Tópico(s): Sesquiterpenes and Asteraceae Studies

1984 - Elsevier BV | Phytochemistry

Artigo Revisado por pares

F G Leonardo Gómez, Leovigildo Quijano, José S. Calderón, Carlos Rengifo Rodriquez, Tirso Ríos,

Tópico(s): Chromatography in Natural Products

1985 - Elsevier BV | Phytochemistry

Artigo Revisado por pares

Leovigildo Quijano, José S. Calderón, Federico Gómez Galindo, Edgar Escobar, Tirso Ríos,

Two new highly oxygenated flavones, were isolated from aerial parts of Ageratum houstonianum. Their structures were established as 3′-hydroxy-5,6,7,8,2′,4′,5′-heptamethoxyflavone and 5,3′-dihydroxy-6,7,8,2′,4′,5′-hexamethoxyflavone on the basis of spectral data and chemical degradation. The structure of the latter compound was confirmed by X-ray analysis.

Tópico(s): Biological Activity of Diterpenoids and Biflavonoids

1985 - Elsevier BV | Phytochemistry

Artigo Revisado por pares

F G Leonardo Gómez, José S. Calderón, Leovigildo Quijano, Martha C. Domínguez, Tirso Ríos,

Abstract A new isoflavone, viridiflorin, has been isolated from Tephrosia viridiflora . Its structure was established as 4′,5,7-trihydroxy-2′,5′-dimethoxy-6-prenylisoflavone based on spectral evidence and chemical transformation.

Tópico(s): Synthesis of Indole Derivatives

1985 - Elsevier BV | Phytochemistry

Capítulo de livro Revisado por pares

Nikolaus H. Fischer, Leovigildo Quijano,

In a search for allelopathic agents from common weeds, Amaranthus palmeri S. Wats (Palmer amaranth) and Ambrosia artemisiifolia L. (Louisiana annual ragweed) have been analysed for their organic natural products. From A. palmeri phytol, chondrillasterol, vanillin, 3-methoxy-4-hydroxynitrobenzene and 2,6-dimethoxy- benzoquinone were isolated. From the roots of Ambrosia artemisiifolia four polyacetylenes, a mixture of sesquiterpene hydrocarbons, methyl caffeate, and a mixture of β-sitosterol and stigmasterol ...

Tópico(s): Weed Control and Herbicide Applications

1985 - American Chemical Society | ACS symposium series

Artigo Revisado por pares

Nikolaus H. Fischer, Jeffrey D. Weidenhamer, James L. Riopel, Leovigildo Quijano, Marios A. Menelaou,

Twenty-four natural and synthetic sesquiterpene lactones were tested as witchweed germination stimulants to determine the essential structural requirements for the stimulation of witchweed germination by dihydroparthenolide. All of the 10 germacranolides tested induced 40–65% germination of witchweed across a broad concentration range, from 10−5 to 10−9 M. The highest activity was observed with a mixture of the two eudesmanolides, santamarin and reynosin. These findings indicate that it is the spatial ...

Tópico(s): Plant Toxicity and Pharmacological Properties

1990 - Elsevier BV | Phytochemistry

Artigo Revisado por pares

José S. Calderón, Leovigildo Quijano, F́ederico Gómez-Garibay, Marina Morán, Tirso Ríos,

The leaves of B. glomerata afforded three new labdane diterpenes. Their structures and stereochemistry were established by spectroscopic methods and chemical transformations.

Tópico(s): Plant Pathogens and Fungal Diseases

1987 - Elsevier BV | Phytochemistry

Artigo Revisado por pares

Antonio Valencia, A. Wens, Héctor Ponce‐Monter, Nieves Pedrón, Alfredo J. Gallegos, Leovigildo Quijano, J. Calderón, F. Gómez, T. Ríos,

Zoapatle aqueous crude extract (ZACE) from Montanoa tomentosa has been used as an oral contraceptive in traditional Mexican medicine for centuries. Kaurenoic acid, as isolated from Montanoa frutescens, and the methyl esters of 15-hydroxy-dihydro-kaurenoic acid and 15-keto-dihydro-kaurenoic acid were tested in vitro on human sperm motility and viability. The estimated ED50 concentrations immobilization were 374, 126 and 58 micrograms/ml, respectively using 15 X 10(6) sperms/500 microliter. Kaurenoic ...

Tópico(s): Phytochemistry and Bioactive Compounds

1986 - Elsevier BV | Journal of Ethnopharmacology

Artigo Revisado por pares

F́ederico Gómez-Garibay, Leovigildo Quijano, José S. Calderón, Sixto Morales, Tirso Ríos,

The roots of Tephrosia quercetorum afforded three new flavonoids named quercetols A, B and C. Their structures were established by spectroscopic methods, mainly 1H NMR.

Tópico(s): Synthesis of Indole Derivatives

1988 - Elsevier BV | Phytochemistry

Artigo

Lauro Olmo Enciso,

... iglesia de Recopolis, ciudad fundada por el rey Leovigildo, en el 578, como definitoria de un tipo ...

Tópico(s): Historical and Religious Studies of Rome

1988 - Spanish National Research Council | Archivo Español de Arqueología