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URI permanente para esta coleçãohttps://locus.ufv.br/handle/123456789/11800

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    Syntheses, crystal structure, spectroscopic characterization and antifungal activity of new N-R-sulfonyldithiocarbimate metal complexes
    (Journal of Inorganic Biochemistry, 2009-07) Alves, Leandro C.; Rubinger, Mayura M. M.; Lindemann, Renata H.; Perpétuo, Genivaldo Júlio; Janczak, Jan; Miranda, Liany D. L.; Zambolim, Laércio; Oliveira, Marcelo R. L.
    Five new compounds with the general formula of (Bu4N)2[M(RSO2NCS2)2], where Bu4N = tetrabutylammonium cation, (M = Ni, R = 4-FC6H4) (1), (M = Zn, R = 4-FC6H4, 4-ClC6H4, 4-BrC6H4, 4-IC6H4), (2), (3), (4) and (5), respectively, were obtained by the reaction of the appropriate potassium N-R-sulfonyldithiocarbimate (RSO2NCS2K2) with nickel(II) chloride hexahydrate or zinc(II) acetate dihydrate in metanol:water 1:1. The elemental analyses and the IR data are consistent with the formation of the expected bis(dithiocarbimato)metal(II) complexes. The 1H and 13C NMR spectra showed the signals for the tetrabutylammonium cation and the dithiocarbimate moieties. The compounds 1, 2 and 5 were also characterized by X-ray diffraction techniques. The nickel(II) is coordinated by two N-4-fluorophenylsulphonyldithiocarbimato(2-) ligands forming a planar coordination. The zinc(II) exhibits distorted tetrahedral configuration in compounds 2 and 5 due to the chelation effect of two sulfur atoms of the N-R-sulfonyldithiocarbimate ligands. The antifungal activities of the compounds were tested in vitro against Colletotrichum gloeosporioides, an important fungus that causes the plant disease known as anthracnose in fruit trees. All the complexes were active.
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    Composition and antifungal activity of the essential oil of the Brazilian Chenopodium ambrosioides L.
    (Journal of Chemical Ecology, 2008-08-05) Jardim, Carolina Marangon; Jham, Gulab Newandram; Dhingra, Onkar Dev; Freire, Marcelo Moreira
    The antifungal activity of essential oil (EO) from the Brazilian epazote (Chenopodium ambrosioides L.) was evaluated by the poison food assay at concentrations of 0.3%, 0.1%, and 0.05% with eight postharvest deteriorating fungi (Aspergillus flavus, Aspergillus glaucus, Aspergillus niger, Aspergillus ochraceous, Colletotrichum gloesporioides, Colletotrichum musae, Fusarium oxysporum, and Fusarium semitectum). EO components were tentatively identified by Kováts retention indices (RIs) using gas chromatography and gas chromatography combined with mass spectrometry (GC-MS). Growth of all fungi was completely inhibited at 0.3% concentration, and by 90% to 100% at 0.1% concentration. The following 13 tentatively identified compounds (relative percent) accounted for 90.4% of the total volatile oil: α-terpinene (0.9), p-cymene (2.0), benzyl alcohol (0.3), p-cresol (0.3), p-mentha-1,3,8-triene (0.2), p-cimen-8-ol (0.6), α-terpineol (0.5), (Z)-ascaridole (61.4), piperitone (0.9), carvacrol (3.9), (E)-ascaridole (18.6), (E)-piperitol acetate (0.5), and (Z)-carvyl acetate (0.3). Autobiographic thin layer chromatography of the EO to separate the principal fungitoxic fraction yielded only one fraction that completely inhibited the growth of all test fungi at a concentration of 0.1%. This fraction was characterized by RIs and GC-MS presenting a composition (%) of p-cymene (25.4), (Z)-ascaridole (44.4), and (E)-ascaridole (30.2). The results suggest ascaridoles were the principal fungitoxic components of the EO.