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Item Sais de tetrafenilfosfônio e tris( 1,10- fenantrolina) ferro( ii) de complexos aniônicos de dibutilestanho( iv) com ditiocarbimatos: síntese, caracterização e atividade antifúngica(Química Nova, 2016-06) Bottega, Fernanda C.; Oliveira, Marcelo R. L.; Rubinger, Mayura M. M.; Bellato, Carlos R.; Ardisson, José D.; Zambolim, LaercioSix new salts of organometallic complexes of tin(IV) with the general formulae: (Ph4P)2[Sn(Bu)2(RSO2N=CS2)2] and [Fe(phen)3][Sn(Bu)2(RSO2N=CS2)2] [Ph4P = tetraphenylphosphonium, R = CH3 (1), C2H5 (2) and C4H9 (3); Fe(phen)3 = tris(1,10-phenanthroline)iron(II), R = CH3 (4), C2H5 (5) and C4H9 (6)] were synthetized from potassium dithiocarbimates (RSO2N=CS2K2.H2O) in reaction with dichlorobis-n-butyltin(IV) and tetraphenylphosphonium chloride (1-3) in N,N-dimethylformamide or tris(1,10-phenanthroline)iron(II) (4-6) in methanol. The new compounds were characterized by elemental analysis of Fe and Sn, and by vibrational, Mössbauer and nuclear magnetic resonance of 1H, 13C and 119Sn spectroscopies. High-resolution mass spectra in the negative and positive modes were also obtained. The elemental analyses and the exact masses obtained for the cations and the complex anions were consistent with the proposed formulae. The Mössbauer spectroscopic data were consistent with the presence of tin(IV) with coordination numbers between 4 and 5 (compounds 1-6), and of hexacoordinated iron(II) (compounds 4-6). The 1H and 13C NMR spectra presented all the expected signals for the cations and anions, and the signals observed in the 119Sn NMR spectra indicated an equilibrium between tetra- and pentacoordination around the tin atoms in solution. The in vitro activity of the new compounds was evaluated against Botrytis cinerea and Colletotrichum acutatum.Item Síntese de 2-( 2- piridil) quinolinas promovida por micro- ondas e suas atividades antifúngicas(Química Nova, 2017-09) Borel, Carmindo R.; Barbosa, Luiz C. A.; Maltha, Célia R. A.; Fernandes, Sergio A.; Santos, Larissa B.; Takahashi, Jacqueline A.In this work a series of 2-(2- pyridyl)quinolines were prepared via a Povarov reaction between anilines, 2-pyridinocarbadehyde and ethyl vinyl ether under microwaves heating conditions. The optimized conditions herein reported allowed the preparation of several pyridylquinolines in yields in the range of 30-83%, some of them not previously accessible by this multicomponent process. The reported methodology has advantage over previous report due to its larger scope and short reaction time (2 hours). All quinolines obtained were assayed against five species of clinically important yeasts Candida sp and against Cryptococcus neoformans. Some of them possessed a broad spectrum of action including 2-(2-pyridyl)quinoline (20) and 6,8-dimethoxy-2-(pyridin-2-yl)quinolone (22) that were highly effective in inhibiting Candida species (IC50 < 1.95 µg/mL against C. tropicalis and C. krusei). Some compounds were more potent than commercial drugs Nistatin and Miconazole.Item Composition, antifungal activity and main fungitoxic components of the essential oil of Mentha piperita L.(Journal of Food Safety, 2011-12-11) Freire, Marcelo Moreira; Jham, Gulab Newandram; Dhingra, Onkar Dev; Jardim, Carolina Marangon; Barcelos, Rosimeire Coura; Valente, Vânia Maria MoreiraTwenty-one components (93.9% of the total chromatographic peak area) were tentatively identified in the essential oil (EO) of Mentha piperita L., based on Kováts retention indices (RIs), a mass spectral database (gas chromatography-mass spectrometry, GC-MS) and visual comparison of the mass spectra of the sample peaks with those of the database. The presence of 15 compounds (corresponding to 90.7% of the total chromatographic peak area) was confirmed by authentic standards. The EO presented a good activity against the following important postharvest deteriorating fungi: Aspergillus flavus, Aspergillus glaucus, Aspergillus niger, Aspergillus ochraceous, Colletotrichum gloesporioides, Colletotrichum musae, Fusarium oxysporum and Fusarium semitectum. At a concentration of 0.2% of the EO, all the fungi were completely inhibited, except for A. glaucus and C. musae which were inhibited 90 and 98%, respectively. TLC-bioautography yielded three subfractions that prevented fungal growth, suggesting the presence of antifungals. Bioassay data of the crude EO were compared with those of the three subfractions. Based on these tests, it was concluded that several fungitoxics were responsible for the antifungal activity of M. piperita, with the principal ones being menthone, neomenthol, menthol and carvone. However, participation of other compounds cannot beruled out. This is the first study in the literature that presents data on the activity of the crude EO against eight important postharvest deteriorating fungi, characterizing the amounts and types of comounds. In addition, also for the first time, the active fractions of the crude EO were isolated, identified and the components quantified. More detailed fungal tests are being conducted to confirm the tentative preliminary antifungal data.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 Synthesis, characterization and biocidal activity of new organotin complexes of 2-(3-oxocyclohex-1-enyl)benzoic acid(European Journal of Medicinal Chemistry, 2010-03) Maia, José R. da S.; Vieira, Flaviana T.; Lima, Geraldo M. de; Speziali, Nivaldo L.; Ardisson, José D.; Rodrigues, Leonardo; Correa Junior, Ary; Romero, Oscar B.The reaction of 1,3-cyclohexadione with 2-aminobenzoic acid has produced the 2-(3-oxocyclohex-1-enyl)benzoic acid (HOBz). Subsequent reactions of the ligand with organotin chlorides led to [Me2Sn(OBz)O]2 (1), [Bu2Sn(OBz)O]2 (2), [Ph2Sn(OBz)O]2 (3), [Me3Sn(OBz)] (4), [Bu3Sn(OBz)] (5) and [Ph3Sn(OBz)] (6). All complexes have been fully characterized. In addition the structure of complexes (2) and (4) have been authenticated by X-ray crystallography. The biological activity of all derivatives has been screened against Cryptococcus neoformans and Candida albicans. In addition we have performed toxicological testes employing human kidney cell. The complexes (3), (5) and (6) displayed the best values of inhibition of the fungus growing, superior to ketoconazole. Compound (5) presented promising results in view of the antifungal and cytotoxicity assays.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 heteroleptic nickel(II) complexes with N-alkylsulfonyldithiocarbimates and phosphines(Journal of Molecular Structure, 2016-06-15) Vidigal, Antonio E. C.; Rubinger, Mayura M. M.; Oliveira, Marcelo R. L.; Guilardi, Silvana; Souza, Rafael A. C.; Ellena, Javier; Zambolim, LaercioFour nickel(II) complexes of general formula [Ni(RSO2NCS2) (PPh3)2] where R = CH3 (2a), CH3CH2 (2b), CH3(CH2)3 (2c) and CH3(CH2)7 (2d) and PPh3 = triphenylphosphine; and two nickel(II) complexes of general formula [Ni(RSO2NCS2)dppe] where R = CH3(CH2)3 (3c) and CH3(CH2)7 (3d) and dppe = 1,2-bis(diphenylphosphine)ethane) were prepared. These new complexes were obtained by the reaction of nickel(II) chloride hexahydrate with potassium N-alkylsulfonyldithiocarbimates and the appropriate phosphine using ethanol/water as solvent. The IR, UV–Vis and ^1 H, ^13 C and ^31 P NMR spectra, elemental analysis of Ni and the HR-ESI-MS were consistent with the formation of square planar nickel(II) complexes with mixed ligands. The structures of the compounds 2b and 2c were determined by single crystal X-ray diffraction. The compounds are isostructural and crystallize in the space group P of the triclinic system. The activities of the complexes were investigated in vitro against Botrytis cinerea, Colletotrichum acutatum and Alternaria solani, fungi species that affect various commercially important plants. All the complexes were active.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 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 MoreiraThe 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.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.