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Digital.CSIC (42.150 recursos)
Repositorio institucional del Consejo Superior de Investigaciones Científicas. Digital.CSIC es un depósito de documentos digitales, cuyo objetivo es organizar, archivar, preservar y difundir en modo de acceso abierto la producción intelectual resultante de la actividad investigadora del CSIC.

(IPNA) Artículos post-print

Mostrando recursos 1 - 20 de 114

1. Insect Growth Regulatory Effects of Linear Diterpenoids and Derivatives from Baccharis thymifolia - Juan Hikawczuk, Virginia E.; Giordano, Óscar S.; Martín, Tomás; Martín, Víctor S.; Tonn, Carlos E.
Linear diterpenes isolated from aerial parts of Baccharis thymifolia (1–3) were tested for insect growth inhibitory activity against Tenebrio molitor larvae. Compounds 4–16 were prepared by various chemical transformations. The diterpenes 6,10-(E,E)-thymifodioic acid (1), the butenolide 3, and the derivatives 4, 11, and 14 produced developmental deficiencies in assays using topical application on fifth instar larvae of T. molitor. Compound 3 is a new natural product.

2. 3-oxo-28,29-dihydroxyolean-12-ene from Orthosphenia mexicana - González, Antonio G.; González, Carmen M.; Ravelo, Ángel G.; Domínguez, Xorge A.; Fraga, Braulio M.
In a previous work we described the structural determination of orthosphenic acid and netzahualcoyone from Orthosphenia mexicana Standley (Celastraceae). Continuing with the chemical examination of this species, we describe here the isolation of a new triterpene, 3-oxo-28,29-dihydroxyolean-12-ene from the aerial parts.

3. Biotransformation of two ent-Pimara-9(11),15-diene derivatives by Gibberella fujikuroi - Fraga, Braulio M.; Guillermo, Ricardo; Hernández, Melchor G.; Chamy, María C.; Garbarino, Juan A.
The incubation of 19-hydroxy-13-epi-ent-pimara-9(11),15-diene (4) with Gibberella fujikuroi gave 8α,19-dihydroxy-9α,11α-epoxy-13-epi-ent-pimara-15-ene (6), 7-oxo-11α,19-dihydroxy-13-epi-ent-pimara-8(9),15-diene (7), 7-oxo-11β,19-dihydroxy-13-epi-ent-pimara-8(9),15-diene (9), and 8α,19-dihydroxy-9α,11α:15,16-diepoxy-13-epi-ent-pimarane (11), while the feeding of 13-epi-ent-pimara-9(11),15-diene-19-oic acid (5) with this fungus afforded 1-oxo-2α,9α-dihydroxy-13-epi-ent-pimara-11,15-dien-19-oic acid (13), 1-oxo-2β,9α-dihydroxy-13-epi-ent-pimara-11,15-dien-19-oic acid (14), 13-epi-ent-pimara-9(11),15-dien-1,19-dioic acid 1,2-lactone (15), and 1-oxo-12β-hydroxy-13-epi-ent-pimara-9(11),15-dien-19-oic acid (16). In both biotransformations, the main reaction was the epoxidation of the 9(11)-double bond, followed by rearrangement to afford allylic alcohols. The formation of lactone 15 represents the first time that a Baeyer−Villiger oxidation has been observed in a microbiological transformation with this fungus.

4. Tetrahydropyran monoterpenes from plocamium cartilagineum and pantoneura plocamioides - Cueto, Mercedes; Darias, José; Rovirosa, Juana; San Martín, Aurelio
Four new marine monoterpenes have been isolated from two species of marine red algae, Plocamium cartilagineum and Pantoneura plocamioides. The structures and relative stereochemistry of these compounds were determined on the basis of spectroscopic evidence and suggest a relationship between P. cartilagineum and P. plocamioides.

5. Pronuciferine N-Oxide, a Proaporphine N-Oxide Alkaloid from Berberis coletioides - Fajardo, Víctor; Araya, Marisel; Cuadra, Pedro; Oyarzun, Alejandra; Gallardo, Amalia; Cueto, Mercedes; Díaz-Marrero, Ana R.; Darias, José; Villarroel, Luis; Álvarez, Celina; Mora-Pérez, Yolanda; Joseph-Nathan, Pedro
Pronuciferine N-oxide (1), a proaporphine N-methyl-N-oxide alkaloid, along with the parent alkaloid pronuciferine (2) were isolated from Berberis coletioides. The structure of the new compound was determined by spectroscopic evidence. Compound 1 is the first naturally occurring proaporphinoid alkaloid with an N-oxide functionality.

6. New prenylated bromoquinols from the green alga Cymopolia barbata - Dorta, Enrique; Darias, José; San Martín, Aurelio; Cueto, Mercedes
Six new prenylated bromohydroquinones, 3'-methoxy-7-hydroxycymopol (1), 3-hydroxycymopolone (2), 3,7-dihydroxycymopolone (3), 7-hydroxycymopochromanone (4), 7-hydroxycymopochromenol (5), and a related 6-hydroxy derivative of cymopochromenol (6), have been isolated from the green marine alga Cymopolia barbata. The structures of these cymopol-related metabolites were determined by spectral methods.

7. Oxachamigrenes, new halogenated sesquiterpenes from Laurencia obtusa - Brito, Inmaculada; Cueto, Mercedes; Díaz-Marrero, Ana R.; Darias, José; San Martín, Aurelio
Two new sesquiterpenes belonging to a novel oxacyclic structural type of chamigrene skeleton, oxachamigrene (1) and 5-acetoxyoxachamigrene (2), have been isolated from the red alga Laurencia obtusa. The structures of the compounds were determined on the basis of spectroscopic evidence. A biogenetic route for these metabolites has been proposed.

8. New terpenoids from the brown alga Stypopodium zonale - Dorta, Enrique; Cueto, Mercedes; Brito, Inmaculada; Darias, José
Three new terpenoids, 1a−3a, and the known metabolites atomaric acid, stypoquinonic acid, and 5'a-desmethyl-5'-acetylatomaric acid have been isolated from the tropical brown alga Stypopodium zonale. The structures and relative stereochemistry of the methyl ester of 1a−3a were determined by spectral methods. The methyl ester of 3a exhibits in vitro cytotoxic activity against human lung and colon carcinoma.

9. Yaretol, a norditerpenoid from Azorella madreporica - Loyola, Luis Alberto; Bórquez, Jorge; Morales, Glauco; San Martín, Aurelio; Manríquez, Víctor; Boys, Daphne; Darias, José
A new norditerpenoid, yaretol (1), was isolated from the whole plant of Azorella madreporica. The structure of 1 was established by one- and two-dimensional NMR techniques and confirmed by X-ray diffraction analysis.

10. Síntesis del Anagadiol* - González, A. G.; Fraga, Braulio M.; Ravelo, Ángel G.
Anagadiol (I B. 3 B-dihydroxy-olean-18-ene) (IX) has been synthesized from germanicol (I)

11. New sources of steroid sapogenin - XVIII: Four new steroid sapogenins from Semele androgyna - González, Antonio G.; Freire, Raimundo; Salazar, José A.; Hernández, Rosendo; Suárez, Ernesto
From the stems and leaves of Semele androgyna L. four new steroid sapogenins have been isolated: isoandrogenin A (Ia) and B (Id), their structures being determined as the 25S- and 25R-isomers of spirost-5-en-1 β, 3β, 25-triol, and androgenin A (IIa) and B (IIc) corresponding to the 25S- and 25R-isomers of (20S, 22S, 25)-furost-5-en-22, 25-epoxy-1 β, 3β, 26-triol.

12. Sintesis de la reineckiagenina e isoreineckiagenina - González, Antonio G.; Freire, Raimundo; Francisco, Cosme G.; Salazar, José A.; Hernández, Rosendo; Suárez, Ernesto
[EN] The 25-hydroxyspirostan sapogenins reineckiagenin (5b) and isoreineckiagenin (5a) have been synthesized from ruscogenin (1a) by a high yield method which may easily be used for preparing this type of compounds.

13. Lagarto gigante de La Gomera. Un fósil que vuelve a la vida - Rando, J. Carlos; Valido, Alfredo; Nogales, Manuel; Martín, Aurelio
Nunca llegó a extinguirse, pero nadie lo había visto desde hace al menos quinientos años. En cualquier caso, no como para darse cuenta de que se trataba de una nueva especie. En junio de 1999 se encontraron los primeros indicios de su presencia actual y pocos días después pudo capturarse un ejemplar de lagarto gigante de La Gomera. Evidentemente, se trata de uno de los reptiles más amenazados del mundo. Hasta la fecha sólo se conocen seis ejemplares supervivientes, todos ellos destinados a un programa de cría en cautividad.

14. Situación actual y problemas de conservación de la hubara canaria - Lortenzo, Juan Antonio; Nogales, Manuel; Martín, Aurelio
Un censo reciente de la población de hubara canaria, que ha incluido por primera vez todas las islas e islotes donde se conocía o sospechaba su presencia, ha permitido estimar una población de 268 ejemplares en Lanzarote, 241 en Fuerteventura y 18 en La Graciosa. Estas cifras superan con creces los resultados de censos anteriores, aunque probablemente se deban a un mejor método de prospección y no a un aumento real de los efectivos. La destrucción y alteración del hábitat de la hubara canaria parece ser el principal problema de conservación que amenaza actualmente a esta subespecie endémica.

15. Tarabilla canaria: ¿por qué tan vulnerable? - Illera, Juan Carlos; Díaz, Mariano; Nogales, Manuel
Hoy en día la tarabilla canaria sólo vive en Fuerteventura. Que no esté asentada en otras islas de Canarias similares y cercanas, como Lanzarote y Lobos, parece indicar un déficit de habitats semiáridos de calidad. La fidelidad a sus territorios actuales hace a esta pequeña ave amenazada muy vulnerable a impactos como el desarrollo turístico, el exceso de pastoreo o la depredación por gatos asilvestrados.

16. Late-Holocene asynchronous extinction of endemic mammals on the eastern Canary Islands - Rando, J. Carlos; Alcover, Josep Antoni; Michaux, Jacques J.; Hutterer, Rainer; Navarro, Juan Francisco
The Lava mouse (Malpaisomys insularis), and the Canarian shrew (Crocidura canariensis) are endemic of the Eastern Canary Islands and islets. The former is extinct while Canarian shrew survives in the two main islands and two islets. In order to provide insights regarding causes and processes contributing to the extinction of these endemic mammals: (i) we established last occurrence dates for Lava mouse, and first records for two exotic species - House mouse (Mus musculus) and Black rat (Rattus rattus) - through direct 14C AMS dating of collagen from bones; (ii) we analysed recent material from Barn owl (Tyto alba gracilirostris)...

17. Dating of the hominid (Homo Neanderthalensis) remains accumulation from El Sidrón cave (piloña, Asturias, North Spain): an example of a multi-methodological approach to the dating of upper pleistocene sites - Torres, T. de; Julià, R.; Soler, V.; Sánchez-Moral, S.; Lalueza-Fox, Carles; Rosas, Antonio; Fortea, Javier
The age of Neanderthal remains and associated sediments from El Sidrón cave has been obtained through different dating methods (14CAMS, U/TH, OSL, ESR and AAR) and samples (charcoal debris, bone, tooth dentine, stalagmitic flowstone, carbonate-rich sediments, sedimentary quartz grains, tooth enamel and land snail shells). Detrital Th contamination rendered Th/U dating analyses of flowstone unreliable. Recent 14C contamination produced spurious age-values from charcoal samples as well as from inadequately pretreated tooth samples. Most consistent 14C dates are grouped into two series: one between 35 and 40 ka and the other between 48 and 49 ka. Most ESR and AAR samples...

18. Interferon regulatory factor 5 (IRF5) gene variants are associated with multiple sclerosis in three distinct populations - Kristjansdottir, G.; Sandling, J. K.; Bonetti, A.; Roos, I. M.; Milani, L.; Wang, C.; Gustafsdottir, S. M.; Sigurdsson, S.; Lundmark, A.; Tienari, P. J.; Koivisto, K.; Elovaara, I.; Pirttilä, T.; Reunanen, M.; Peltonen, L.; Saarela, J.; Hillert, J.; Olsson, T.; Landegren, U.; Alcina, Antonio; Fernández, Óscar; Leyva, Laura; Guerrero, Miguel; Lucas, Miguel; Izquierdo, Guillermo; Matesanz, F.; Syvänen, A. C.
Background: IRF5 is a transcription factor involved both in the type I interferon and the toll-like receptor signalling pathways. Previously, IRF5 has been found to be associated with systemic lupus erythematosus, rheumatoid arthritis and inflammatory bowel diseases. Here we investigated whether polymorphisms in the IRF5 gene would be associated with yet another disease with features of autoimmunity, multiple sclerosis (MS). Methods: We genotyped nine single nucleotide polymorphisms and one insertion-deletion polymorphism in the IRF5 gene in a collection of 2337 patients with MS and 2813 controls from three populations: two case-control cohorts from Spain and Sweden, and a set of...

19. Phylogeography and demographic history of Lacerta lepida in the Iberian Peninsula: multiple refugia, range expansions and secondary contact zones - Miraldo, Andreia; Hewitt, Godfrey M; Paulo, Octavio S; Emerson, Brent C
Abstract Background The Iberian Peninsula is recognized as an important refugial area for species survival and diversification during the climatic cycles of the Quaternary. Recent phylogeographic studies have revealed Iberia as a complex of multiple refugia. However, most of these studies have focused either on species with narrow distributions within the region or species groups that, although widely distributed, generally have a genetic structure that relates to pre-Quaternary cladogenetic events. In this study we undertake a detailed phylogeographic analysis of the lizard species, Lacerta lepida, whose distribution encompasses the entire Iberian Peninsula. We attempt to identify refugial areas, recolonization routes,...

20. The construction of open GdIII metal–organic frameworks based on methanetriacetic acid: New objects with an old ligand - Cañadillas-Delgado, Laura; Martín, Tomás; Fabelo, Oscar; Ruiz-Pérez, Catalina
The preparation, X-ray crystallography and magnetic investigation of the first examples of methanetriacetate (mta)-containing lanthanide(III) complexes of formulae [Gd(mta)(H2O)3]n⋅4 n H2O (1) [Gd(mta)(H2O)3]n⋅2 n H2O (2) and [Gd2(mta)2(H2O)2]n⋅2 n H2O (3) are described herein. This tripodal ligand promotes the formation of 63 networks; thus 1 consists of a honeycomb structure, whereas in 2 two of these layers are condensed to form a rare five-connected two-dimensional (4862) network. Compound 3 can be seen as an aggregation of 63 layers leading to a three-dimensional (6,6)-connected binodal (41263)(4966)-nia net, in which the gadolinium(III) ions and the mta ligands act as octahedral and as trigonal prismatic nodes, respectively. The magnetic...

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