Browsing by Author "Cortes, M"

Now showing 1 - 6 of 6
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    Microbial hydroxylation of natural drimenic lactones
    (PERGAMON-ELSEVIER SCIENCE LTD, 1999) Maurs, M; Azerad, R; Cortes, M; Aranda, G; Delahaye, MB; Ricard, L
    Incubation of confertifolin and isodrimenin with Mucor plumbeus, Aspergillus niger or Rhizopus arrhizus gave in good yields the corresponding 3 beta-hydroxy derivatives. From isodrimenin, the known natural 7 alpha-hydroxy derivative (futronolide) was also obtained and its structure was definitely established by X-ray crystallographic study of its acetate derivative. (C) 1999 Elsevier Science Ltd. All rights reserved.
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    Partial synthesis of (-)-11,12-dinordriman-8-one and the (-)-enantiomer of polywood
    (SCIENCE REVIEWS 2000 LTD, 1998) Cortes, M; Moreno, L; Lopez, J
    A chiral sequiterpene diol 6, readily available from the natural product polygodial (4), has been used for the first partial synthesis of the title compounds.
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    Practical and efficient 1 alpha-hydroxylation of 4,4-dimethyl-2-ene derivatives in terpenic series.
    (1997) Aranda, G; BertranneDelahaye, M; Azerad, R; Maurs, M; Cortes, M; Ramirez, H; Vernal, G; Prange, T
    The third part of a triptycal synthesis providing 1 alpha-hydroxy compounds, through microbial hydroxylation in position-3 of terpenoid substrates, followed by dehydration to 4,4-dimethyl-2-ene compounds and subsequent allylic hydroxylation by SeO2/pyridine N-oxide, is described.
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    Proximate composition and biological activity of Chilean Prosopis species
    (WILEY, 2000) Astudillo, L; Schmeda Hirschmann, G; Herrera, JP; Cortes, M
    The proximate and amino acid compositions of the leaves and pods of Prosopis chilensis and P tamarugo and the leaves of P alba have been assessed. The biological activity of the leaves and pods of the first two species as well as the leaves and exudate of P alba has been determined for free radical scavenging activity, xanthine oxidase inhibition and DNA binding. The best protein source among the forage trees was the leaves of P chilensis; P alba and P tamarugo leaves showed higher crude protein, fat and nitrogen-free extract values than reported in previous studies. According to their amino acid profiles, all species surveyed are deficient in essential amino acids. The alkaloids beta-phenethylamine and tryptamine were isolated from P chilensis, and phenethylamine was detected in P tamarugo. At 0.50 mg ml(-1), both compounds showed DNA binding activity, with values of 18.5 and 11% respectively. The exudate of P alba showed a strong fi ee radical scavenging effect. The activity was related with the total phenolics content, consisting mainly of catechin. (C) 2000 Society of Chemical Industry.
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    Studies on quinones. Part 38: Synthesis and leishmanicidal activity of sesquiterpene 1,4-quinones
    (PERGAMON-ELSEVIER SCIENCE LTD, 2003) Valderrama, JA; Benites, J; Cortes, M; Pessoa Mahana, H; Prina, E; Fournet, A
    The reaction of (+)-euryfuran 1 with several benzo-, naphtho- and benzo[b]thiophene-1,4-quinones in acetic acid yields the corresponding euryfuryl-1.4-quinones 3, 5, 7, 8, 10, 12, and 14. The structure of compounds 7, 8, 12, and 14 was assigned through 2D NMR H-1-C-13 HMBC experiments. The influence of the acidity of the solvent upon the reactivity and regioselectivity of the quinones to the oxidative coupling reaction, is discussed. The in vitro activity of the euryfurylquinones and their corresponding precursors against Leishmania amazonensis is described. (C) 2003 Elsevier Ltd. All rights reserved.
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    Synthesis of 11,12-epoxydrim-8,12-en-11-ol, 11,12-diacetoxydrimane, and warburganal from (-)-sclareol
    (AMER CHEMICAL SOC, 1999) Barrero, AF; Cortes, M; Manzaneda, EA; Cabrera, E; Chahboun, R; Lara, M; Rivas, AR
    The first syntheses are reported for recently isolated drimanes 11,12-epoxydrim-8,12-en-11-ol (2) and 11,12-diacetoxydrimane (3), from (-)-sclareol (1). Furthermore, two efficient new routes to the potent bioactive warburganal (4) starting also from 1 are described.