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URI permanente para esta coleçãohttps://locus.ufv.br/handle/123456789/11800
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Item Influência da matéria orgânica na adsorção do fungicida triadimenol pelo solo(Química Nova, 2002-07) Lopes, Nilva Pereira; Queiroz, Maria Eliana Lopes Ribeiro de; Neves, Antônio Augusto; Zambolim, LaércioThe adsorption of triadimenol (1-(4-chlorophenoxy)-3,3-dimethyl-1-(1H-1,2,4-triazol-1-yl)butan-2-ol) on soil samples with varying contents of organic matter was studied. The adsorption was described by means of the Freundlich's isoterm. An increase in the capacity of adsorption was observed as the content of organic carbon in the matrix increased. That effect was observed when removing the organic matter from the soil, when adding a urban waste compost to the soil sample as well as to the soil sample without organic matter, and also after leaving proportions of urban waste compost incubated in these matrices for a period of 120 days. The results show that the adsorption of the triadimenol in the soil is dependent of its content of organic carbon.Item Bis(4-fluorophenylsulfonyldithiocarbimato) zincate(ii) salts: new antifungals for the control of botrytis blight(Química Nova, 2015-07) Oliveira, Alexandre A.; Oliveira, Marcelo R. L.; Rubinger, Mayura M. M.; Piló, Elisa L.; Menezes, Daniele C.; Zambolim, LaércioBotrytis blight or gray mold is a highly destructive disease caused by Botrytis spp., that infects flowers, trees vegetables, fruit, especially grapevines and strawberry. Three new compounds with general formula (A)2[Zn(4-FC6H4SO2N=CS2)2], where A = PPh3CH3 (2a), PPh3C2H5 (2b), PPh3C4H9 (2c), and the previously published compounds where A = PPh4 (2d) and NBu4 (2e), were synthesized by the reaction of 4-fluorophenylsulfonyldithiocarbimate potassium dihydrate and zinc(II) acetate dihydrate with the appropriate counter cations (A) halides. The new compounds were characterized by infrared, 1H and 13C NMR spectroscopies. All these salts inhibited the growth of Botrytis cinerea, with compounds 2c and 2d showing greater antifungal activity than zinc dimethyldithiocarbamate, the active principle of the fungicide Ziram. The bis(dithiocarbimate)zincate(II) salts are also active against the bacteria Escherichia coli and Staphylococcus aureus.Item Nickel complexes with phosphines and N-R-sulfonyldithiocarbimates ligands: New antifungals for the control of Hemileia vastatrix and Phakopsora pachyrhizi(Inorganica Chimica Acta, 2019-02-24) Vidigal, Antonio E. C.; Rubinger, Mayura M. M.; Queiroz, Luan F. de; Silva, Lucas F. da; Zambolim, Laércio; Guilardi, Silvana; Souza, Rafael A. C.; Ellena, Javier; Wetler, Emiliana B.; Oliveira, Marcelo R. L.Nickel(II) complexes of general formula [Ni(RSO2N = CS2)(PPh3)2] (2a–h) or [Ni(RSO2N = CS2)dppe] (3a–h), where R = methyl (a), ethyl (b), butyl (c), octyl (d), phenyl (e), 4-isopropylphenyl (f), 4-tert-butylphenyl (g), 2-naphthyl (h), PPh3 = triphenylphosphine and dppe = 1,2-bis(diphenylphosphine)ethane were prepared, from which six are new substances (2f–h and 3f–h). The new compounds were characterized by elemental analysis of C, H, N and Ni, and by IR, UV–Vis and 1H, 13C and 31P NMR spectroscopies. The data were consistent with the formation of square planar nickel(II) complexes with mixed ligands, what was confirmed by single crystal X-ray diffraction studies on compounds 2f and 2h. These complexes present intramolecular NiHC anagostic interactions. All complexes inhibited the germination of Hemileia vastatrix and Phakopsora pachyrhizi, the causal agents of devastating diseases on soybean and coffee cultures. The most active compounds presented IC90 values as low as 405 µM against H. vastatrix, and 280 μM against P. pachyrhizi. Thus, the title compounds are target molecules for the development of new agrochemicals against the Asian soybean rust and Coffee leaf-rust diseases.Item 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.Item Tetraphenylphosphonium allyldithiocarbimates derived from Morita- Baylis-Hillman adducts: Synthesis, characterization, crystal structure and antifungal activity(Journal of Molecular Structure, 2016-02-15) Tavares, Eder C.; Rubinger, Mayura M. M.; V. Filho, Eclair; Oliveira, Marcelo R. L.; Piló-Veloso, Dorila; Ellena, Javier; Guilardi, Silvana; Souza, Rafael A. C.; Zambolim, LaércioBotrytis blight is a very destructive disease caused by Botrytis spp., infecting flowers, trees, vegetables and fruits. Twelve new compounds were prepared by the reaction of potassium N-aryl-sulfonyldithiocarbimates with Morita-Baylis-Hillman derivatives bearing phenyl and furyl groups. These are the first examples of allyldithiocarbimate anions and were isolated as tetraphenylphosphonium salts. The new compounds were characterized by HRMS, NMR and Infrared spectroscopy. Further, the structures of three allyldithiocarbimates were determined by single crystal X-ray diffraction. The compounds are isostructural and crystallize in the space group P21/c of the monoclinic system, and the allyldithiocarbimate anions present Z configuration. All the compounds were active against Botrytis cinerea. The best results were achieved with the tetraphenylphosphonium (Z)-3-(furan-2-yl)-2-(methoxycarbonyl)allyl-(4-chlorophenylsulfonyl)dithiocarbimate (IC50 38 μM).Item Syntheses, characterization and antifungal activity of novel dimethylbis(N-R-sulfonyldithiocarbimato)stannate(IV) complexes(Elsevier Journal of Molecular Structure, 2017-02-05) Bomfim Filho, Lucius F. O.; Oliveira, Marcelo R. L.; Miranda, Liany D. L.; Vidigal, Antonio E. C.; Guilardi, Silvana; Souza, Rafael A. C.; Ellena, Javier; Ardisson, José D.; Zambolim, Laércio; Rubinger, Mayura M. M.Four new complexes of the general formula: Ph4P)2[Sn(CH3)2(RSO2NCS2)2], where Ph4P = tetraphenylphosphonium cation and R = CH3, (1), CH3CH2 (2), C6H5 (3), 4-FC6H4 (4), were prepared by the reaction of the appropriate potassium N-R-sulfonyldithiocarbimates, K2(RSO2NCS2), and tetraphenylphosphonium chloride with dimethyltin dichloride. The compounds 1–4 were characterized by 1H, 13C and 119Sn NMR, 119Sn Mössbauer, vibrational spectroscopy and by elemental analyses of C, H, N and Sn. The crystal structure of 1 was determined by X-ray diffraction techniques. The in vitro antifungal activity of the tin(IV) complexes were evaluated against the fungi Rhizoctonia solani and Botrytis cinerea by the Poisoned food test. The new compounds showed comparable activities to the fungicides manzate and ziram.Item Determination of pesticides in lettuce using solid–liquid extraction with low temperature partitioning(Food Chemistry, 2015-02-20) Costa, Anna I.G.; Queiroz, Maria E.L.R.; Neves, Antônio A.; Sousa, Flaviane A. de; Zambolim, LaércioThis work describes the optimization and validation of a method employing solid–liquid extraction with low temperature partitioning (SLE/LTP) together with analysis by gas chromatography with electron capture detection (GC/ECD) for the determination of nine pesticides (chlorothalonil, methyl parathion, procymidone, endosulfan, iprodione, λ-cyhalothrin, permethrin, cypermethrin, and deltamethrin) in lettuce. The method was found to be selective, accurate, and precise, with means recovery values in the range of 72.3–103.2%, coefficients of variation ⩽12%, and detection limits in the range 0.4–37 μg kg−1. The matrix components significantly influence the chromatographic response of the analytes (above 10%). The optimized and validated method was applied to determine the residual concentrations of the fungicides iprodione and procymidone that had been applied to field crops of lettuce. The maximum residual concentrations of the pesticides in the lettuce samples were 13.6 ± 0.4 mg kg−1 (iprodione) and 1.00 ± 0.01 mg kg−1 (procymidone), on the day after application of the products.Item Synthesis and antifungal activity of halogenated aromatic bis-γ-lactones analogous to avenaciolide(Química Nova, 2011-11-08) Castelo-Branco, Pedro A.; Rubinger, Mayura M. M.; Alves, Leandro de C.; Liberto, Natalia A.; Nepel, Thayane C. M.; Catrinck, Mariana; Guilardi, Silvana; Silvério, Hudson A.; Zambolim, Laércio; Piló-Veloso, Dorila; F. Neto, Wilson P.Here we describe the total syntheses and characterization by elemental analyses, infrared and NMR spectroscopy of three new compounds analogous to avenaciolide, a bis-γ-lactone isolated from Aspergillus avenaceus that possesses antifungal activity, where the octyl group of the natural product was replaced by aromatic groups containing chlorine and fluorine atoms. The effects of the avenaciolide, the novel compounds and their synthetic precursors on mycelia development and conidia germination of Colletotrichum gloeosporioides and Fusarium solani were evaluated in vitro. The title compounds were almost as active as avenaciolide. The absolute structures of the chlorinated analogs were determined by X-ray diffraction analysis.Item Synthesis and antifungal activity of aromatic bis-g-lactones analogous to avenaciolide(Chemistry & Biodiversity, 2007-02-13) Castelo-Branco, Pedro A.; Rubinger, Mayura M. M.; Alves, Leandro de C.; Barros, Pauline M. de; Pereira, Sinval G.; Melo, Vanessa J. de; Pilo-Veloso, Dorila; Zambolim, LaércioAvenaciolide is a bis-γ-lactone isolated from Aspergillus avenaceus and possesses antifungal activity. Here, we describe the total syntheses and characterization by elemental analyses, and IR and NMR spectroscopy of three new bis-γ-lactones analogous to avenaciolide, where the octyl group of the natural product was replaced by aromatic groups. The effects of the avenaciolide, the novel compounds, and their synthetic precursors on the mycelia development and conidia germination of Colletotrichum gloeosporioides were evaluated in vitro. The new compounds were as active as avenaciolide in the tested conditions, while the synthetic precursors were inactive. The preparation and characterization of 15 new synthetic intermediates are also described.