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Puerto Serrano, Spain

Abad A.,University of Valencia | Agullo C.,University of Valencia | Cunat A.C.,University of Valencia | Gonzalez-Coloma A.,Institute Ciencias Agrarias CCMA | Pardo D.,University of Valencia
European Journal of Organic Chemistry | Year: 2010

The preparation of 9α-fluoro analogues of both natural and unnatural drimane-type sesquiterpenes is described. Their synthesis began with the initial preparation of methyl 8-keto-12-nordriman-11-oate from β-ionone and entailed the electrophilic fluorination of C-9 for the stereoselective introduction of the fluorine atom. The drimane skeleton was completed from, the intermediate 9α-fluoro-8-keto-12-nordrimane system by means of different reactions at the C-8 ketone carbonyl group, essentially Wittig methylenation, cyanohydrin formation or palladium-catalysed carbonylation of the corresponding enol triflate. Further manipulation of the functionalization derived from these key reactions allowed the preparation, among others, of 9α-fluorodrimanes, which are structurally and functionally related to albicanic acid, drimenin and olepupuane. Also described are the reactivities of some of the fluorine-containing systems prepared and a comparative study of the antifeedant activities of a selection of 9α-fluorodrimanes and the corresponding hydrogen analogues against several, insect species with different feeding ecologies (Spodoptera littoralis, Myzus persicae and Rhopalosiphum padi), which revealed a significant increase in the antifeedant activities of some of the fluorinated drimane analogues. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA. Source

Rodilla J.M.,University of Beira Interior | Silva L.A.,University of Beira Interior | Martinez N.,Catedra de Farmacognosia y Productos Naturales | Lorenzo D.,Catedra de Farmacognosia y Productos Naturales | And 7 more authors.
Industrial Crops and Products | Year: 2011

Bulnesia sarmientoi Lorentz ex Griseb volatile oil was characterized by GC × GC-TOF-MS analysis. Major components were guaiol and bulnesol, followed by hanamyol. The enhanced sensitivity and superior resolution of GC × GC resulted in the identification of thus-far unreported oil constituents as β-guaiene, guaioxide, elemol, germacrene-B, eudesm-5-en-11-ol, γ-eudesmol, α-eudesmol and (-)-hanamyol. The insecticidal effect of B. sarmientoi oil and its main constituents (guaiol, bulnesol and hanamyol) on Spodoptera littoralis, Rhopalosiphum padi and Myzus persicae was studied. Guaiol affected the aphids in a dose-response fashion, showing low efficiency, while bulnesol and hanamyol were inactive. Both the oil and its constituents were also assayed for antifungal action against Fusarium spp. and phytotoxicity to Lactuca sativa. Among the pure compounds tested, bulnesol had a low-moderate effect on Fusarium moniliforme while hanamyol had a strong effect on Fusarium solani. Neither the oil nor the tested compounds affected L. sativa germination or radicle length, indicating that B. sarmientoi is not phytotoxic. © 2010 Elsevier B.V. Source

Gonzalez-Coloma A.,Institute Ciencias Agrarias CCMA | Delgado F.,Polytechnic Institute of Coimbra | Rodilla J.M.,University of Beira Interior | Silva L.,University of Beira Interior | And 2 more authors.
Biochemical Systematics and Ecology | Year: 2011

The chemical composition and biological activity of wild Lavandula luisieri (Rozeira) Rivas-Martínez populations from the south Beira interior region in central eastern Portugal are described. The essential oils of these four populations have been analyzed by GC-MS, and their antifeedant effects evaluated against Spodoptera littoralis, Myzus persicae and Rhopalosiphum padi. Relative concentration data (% values) was subjected to principal component and cluster analysis. Relative concentration data and antifeedant effects were subjected to a stepwise multiple regression analysis. Additionally, one of these populations has been adapted to experimental field cultivation. © 2010 Elsevier Ltd. Source

Mazoir N.,Cadi Ayyad University | Benharref A.,Cadi Ayyad University | Bailen M.,Institute Ciencias Agrarias CCMA | Reina M.,CSIC - Institute of Natural Products and Agrobiology | And 2 more authors.
Zeitschrift fur Naturforschung - Section C Journal of Biosciences | Year: 2011

The in vitro activity on Leishmania infantum promastigotes and Trypanosoma cruzi epi-mastigotes of 25 semisynthetic terpenoid derivatives has been evaluated. These compounds were obtained through chemical modifi cations of the major components of Euphorbia res-inifera (α-euphol and α-euphorbol) and Euphorbia offi cinarum (obtusifoliol and 31-norla-nosterol). Leishmaniasis and Chagas ́ disease are major worldwide health problems. The drugs of choice for their treatment are still problematic in both cases, and therefore there is an urgent need to discover new drugs with high activity and low side effects. Natural products have become a key source of new drugs in the last years. The genus Euphorbia has been the subject of abundant phytochemical and pharmacological research because of its potential medical applications, but the antiparasitic effects of derivatives from plants of this genus are still unknown. Our results showed that 76% and 64% of the test compounds had antiparasitic effects on L. infantum and T. cruzi, respectively. The different activities on both parasites, especially their moderate effects on mammalian cells, indicate an interesting selective toxicity. © 2011 Verlag der Zeitschrift für Naturforschung, Tübingen. Source

Jaramillo-Colorado B.,University of Cartagena | Julio-Torres J.,University of Cartagena | Duarte-Restrepo E.,University of Cartagena | Gonzalez-Coloma A.,Institute Ciencias Agrarias CCMA | Julio-Torres L.F.,Institute Ciencias Agrarias CCMA
Boletin Latinoamericano y del Caribe de Plantas Medicinales y Aromaticas | Year: 2015

The objectives of this work were to study the volatile chemical composition of essential oil (EO) from Piper marginatun Jacq (Piperaceae), obtained from plants collected in two Colombian geographic locations: municipalities Acandí (Chocó) and Turbaco (Bolívar). Also, evaluate their antioxidant, repellent and antifeedant properties. EOs were isolated by hydrodistillation technique and identified by gas chromatography coupled to a mass spectrometric detector (GC-MS). The major compounds found in P. marginatum collected in Acandi were cis-p-anethole (46.3%), estragole (28.9%), safrole (9.0%), while in P. marginatum from Turbaco were germacrene D (36.6%), β-elemene (12.6%), germacren-D-4-ol (5.4%). The antioxidant activity of the EOs were determined using the method of DPPH radical. The percentages of inhibition of DPPH. of P marginatum from Turbaco and Acandí were 90.0% and 73.7%, respectively. The EO from Turbaco had the highest repellent activity against Tribolium castaneum, at a concentration of 0.1 uL /cm2 at 2 and 4 hours of exposure (85% and 76% respectively). P. marginatum from Turbaco was more active against Spodoptera littoralis larvae (Percent feeding inhibition, FI= 80.6%) and a high Percent settling inhibition of Myzus persicae and Rhopalosiphum padi (SI = 87.9% and 86, 4%). © 2015. Source

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