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Item Preparation, X-ray structural studies and plant growth regulatory activity of methyl 6a,7b-thiocarbonyldioxyvouacapan-17 b-oate(Journal of the Brazilian Chemical Society, 2004-03) Rubinger, Mayura M. M.; Borges, Eduardo E. L.; Castelo-Branco, Pedro de A.; Guilardi, Silvana; Souza, Elysângela M. R.; Gambardella, Maria T. do P.; Ferreira-Alves, Dalton L.; Piló-Veloso, DorilaThe 6a,7b-dihydroxyvouacapan-17b-oic acid (1) and methyl 6a,7b-dihydroxyvouacapan-17b-oate (2) are natural products isolated from the hexane extract of Pterodon polygalaeflorus Benth fruits. Here we describe the preparation and characterization by infrared and nuclear magnetic resonance spectroscopy, and by elemental analysis of the novel derivative methyl 6a,7b-thiocarbonyldioxyvouacapan-17b-oate (5), from the ester 2. The structure of compound 5 was determined by X-ray diffraction. At the concentration of 100 ppm, this compound inhibited the radicle growth of Sorgum bicolor L. (-28%) and showed no significant effect on Cucumis sativus L..Item Avaliação de bis(4-metilfenilditiocarbimato)zincato(II) de tetrabutilamônio como acelerador em composições de borracha natural(Polímeros, 2008) Mariano, Roberta M.; Visconte, Leila L. Y.; Oliveira, Marcelo R. L.; Rubinger, Mayura M. M.Neste trabalho a substância ZNIBU [bis(4-metilfenilditiocarbimato)zincato(II) de tetrabutilamônio] foi usada em formulações de borracha natural (NR) e o seu efeito como acelerador de vulcanização foi investigado. As composições, vulcanizadas com a substância em questão, foram submetidas a testes mecânicos e os resultados comparados com os de outras composições vulcanizadas com os aceleradores comerciais CBS (N-ciclohexil-2-benzotiazol-2-sulfenamida), TMTD (dissulfeto de tetrametiltiuram) e MBTS (dissulfeto de benzotiazol). Propriedades como dureza, resiliência e densidade foram avaliadas em presença ou não da carga negro de fumo.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 Síntese e caracterização de novos organometálicos de estanho (iv) com ligantes ditiocarbimatos e sua ação acceleradora na vulcanização de borracha nitrílica(Química Nova, 2016-08) Bottega, Fernanda C.; Oliveira, Marcelo R. L.; Sérvulo, Vanessa Pio; Visconte, Leila L. Y.; Ardisson, José D.; Rubinger, Mayura M. M.This paper describes the synthesis of four new organotin compounds of general formula: (Ph4P)[Sn(Cy)3(RSO2N=CS2)] [Ph4P = tetraphenylphosphonium cation, Cy = cyclohexyl, R = C6H5 (1), 4-ClC6H4 (2), 4-BrC6H4 (3) and 4-IC6H4 (4)]. They were obtained by the reaction between four different potassium N-R-sulfonyldithiocarbimate salts and tricyclohexyltin chloride in methanol, and were isolated as tetraphenylphosphonium salts. The elemental analyses of C, H, N and the data of high-resolution mass spectrometry were consistent with the proposed formulae. The 119Sn NMR spectra and 119Sn Mössbauer spectroscopic data were consistent with the presence of tetracoordinated tin(IV) species in solution and in the solid state. The electrolytic molar conductance and the integration curves in the 1H NMR spectra are in accord with the 1:1 proportion between the tetraphenylphosphonium cations and the complex anions. The activity of the new compounds in the vulcanization of nitrile rubber was evaluated and the results were compared to those achieved with the commercial accelerators: N-tert-butyl-2-benzothiazolesulfenamide (TBBS), tetramethylthiuram disulfide (TMTD) and zinc diethyldithiocarbamate (ZEDC).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 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 and characterization of novel heteroleptic nickel complexes with dithiocarbimates and trithiocarbimates(Inorganica Chimica Acta, 2017-06-01) Castro, Rodrigo A.; Oliveira, Marcelo R. L.; Janczak, Jan; Rubinger, Mayura M. M.The potassium N-R-sulfonyldithiocarbimates, K2(RSO2NCS2) [R = CH3 (1a), CH3CH2 (1b), C6H5 (1c), 2-CH3C6H4 (1d) and 4-CH3C6H4 (1e)], reacted with nickel sulfate or zinc acetate to yield complex anions which were isolated as their tetraphenylphosphonium salts with the formulae (PPh4)2[M(RSO2NCS2)2], were M = Ni (2a–2e) and M = Zn (3a–3e). The compounds 3a–3e readily react with sulfur in dimethylformamide producing bis(trithiocarbimato)-zinc complexes (4a–4e) with the formula (PPh4)2[Zn(RSO2NCS3)2]. Mixed nickel complexes (5a–5e), (PPh4)2[Ni(RSO2NCS2)(RSO2NCS3)], were obtained from the zinc compounds 4a–4e by reaction with nickel sulfate in dimethylsulfoxide. The complexes 5a–5e are the first examples of N-R-sulfonyldithiocarbimate and N-R-sulfonyltrithiocarbimate heteroleptic nickel complexes. The structures of 5a and 5e were determined by X-ray crystallography. Both compounds crystallize in the centrosymmetric space group of the triclinic system. The Ni2+ cation is S,S-chelated by one dithio- and one trithiocarbimate ligands, forming distorted square-planar configurations. The square planar geometry around the nickel atom was confirmed for compounds 5a–5e by electronic, vibrational and nuclear magnetic resonance spectroscopies. High-resolution mass spectrometry and elemental analyses confirmed the molecular formulae.Item Synthesis, structural and spectroscopic characterization of novel zinc(II) complexes with N-methylsulfonyldithiocarbimato and N-methylsulfonyltrithiocarbimato ligands(Polyhedron, 2007-01-02) Oliveira, Marcelo R. L.; Perpetuo, Genivaldo J.; Janczak, Jan; Rubinger, Mayura M. M.Two new zinc(II)-complexes, dithiocarbimato (Ph4P)2[Zn(CH3SO2N=CS2)2] (1) and trithiocarbimato (Ph4P)2[Zn(CH3SO2N=CS3)2] (2), were obtained in the crystalline form by the reaction of potassium N-methylsulfonyldithiocarbimate (RSO2N=CS2K2) with zinc(II) acetate dihydrate and tetraphenylphosphonium chloride in dimethylformamide. Both complexes crystallize in the monoclinic system. The central Zn(II) ion has a distorted tetrahedral coordination in both compounds. In 1 the dithiocarbimato ligand coordinates via two S atoms while in 2 the trithiocarbimato ligand coordinates via S and N atoms. Both complexes were also characterized by IR, 1 H NMR and 13C NMR spectroscopies. Compound 2 is the first example of a zinc(II)-trithiocarbimato complex.Item Preparation, crystal structure and spectroscopic characterization of nickel(II) complexes with dithiocarbimate derivated of sulfonamides(Polyhedron, 2006-07-10) Oliveira, Marcelo R. L.; Franca, Eduardo de Faria; Guilardi, Silvana; Andrade, Renato Pereira de; Lindemann, Renata Hernandez; Amim Jr., Jorge; Ellena, Javier; Bellis, Vito M. de; Rubinger, Mayura M. M.This work describes the syntheses of three compounds containing [Ni(RSO2N=CS2)2]^2 anions: (Bu4N)2[Ni(CH3CH2SO2N=CS2)2] (1), (Bu4N)2[Ni(4-IC6H4SO2N=CS2)2] (2) and (Bu4N)2[Ni(2,5-Cl2C6H3SO2N=CS2)2] (3). They were obtained in the crystalline form by the reaction of the appropriate potassium N-R-sulfonyldithiocarbimate (RSO2N=CS2K2) with nickel(II) chloride hexahydrate in methanol/water. Elemental analyses were consistent with the proposed formulae. UV–Vis and IR data are consistent with the formation of nickel–sulfur diamagnetic planar complexes. The 1H NMR and 13C NMR spectra showed the expected signals for the tetrabutylammonium cation and the dithiocarbimate moieties. Single crystal structure analyses showed that 1 crystallizes in the monoclinic space group P21/n, 2 crystallizes in the monoclinic space group P21/c and 3 crystallizes in the triclinic space group Pī. In these compounds the Ni. atom is coordinated to four S atoms in a distorted square plane geometry due to the asymmetric bidentade chelation by each ligand.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.