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排序方式: 共有100条查询结果,搜索用时 15 毫秒
61.
Paola S. Hellwig Jonatan S. Guedes Angelita M. Barcellos Gelson Perin Eder J. Lenardo 《Molecules (Basel, Switzerland)》2021,26(8)
We describe herein an alternative transition-metal-free procedure to access 3,4-bis(butylselanyl)selenophenes and the so far unprecedented 3-(butylselanyl)-4-alkoxyselenophenes. The protocol involves the 5-endo-dig electrophilic cyclization of 1,3-diynes promoted by electrophilic organoselenium species, generated in situ through the oxidative cleavage of the Se-Se bond of dibutyl diselenide using Oxone® as a green oxidant. The selective formation of the title products was achieved by controlling the solvent identity and the amount of dibutyl diselenide. By using 4.0 equiv of dibutyl diselenide and acetonitrile as solvent at 80 °C, four examples of 3,4-bis(butylselanyl)selenophenes were obtained in moderate to good yields (40–78%). When 3.0 equiv of dibutyl diselenide were used, in the presence of aliphatic alcohols as solvent/nucleophiles under reflux, 10 3-(butylselanyl)-4-alkoxyselenophenes were selectively obtained in low to good yields (15–80%). 相似文献
62.
Helen A. Goulart Daniela R. Araujo Filipe Penteado Raquel G. Jacob Gelson Perin Eder J. Lenardo 《Molecules (Basel, Switzerland)》2021,26(24)
Oxone is a commercially available oxidant, composed of a mixture of three inorganic species, being the potassium peroxymonosulfate (KHSO5) the reactive one. Over the past few decades, this cheap and environmentally friendly oxidant has become a powerful tool in organic synthesis, being extensively employed to mediate the construction of a plethora of important compounds. This review summarizes the recent advances in the Oxone-mediated synthesis of N-, O- and chalcogen-containing heterocyclic compounds, through a wide diversity of reactions, starting from several kinds of substrate, highlighting the main synthetic differences, advantages, the scope and limitations. 相似文献
63.
Livio Racan Ivo Zlatar Nataa Perin Maja Cindri Vedrana Radovanovi Mihailo Banjanac Suresh Shanmugam Marijana Radi Stojkovi Karmen Braja Marijana Hranjec 《Molecules (Basel, Switzerland)》2021,26(16)
Newly designed and synthesized cyano, amidino and acrylonitrile 2,5-disubstituted furane derivatives with either benzimidazole/benzothiazole nuclei have been evaluated for antitumor and antimicrobial activity. For potential antitumor activity, the compounds were tested in 2D and 3D cell culture methods on three human lung cancer cell lines, A549, HCC827 and NCI-H358, with MTS cytotoxicity and BrdU proliferation assays in vitro. Compounds 5, 6, 8, 9 and 15 have been proven to be compounds with potential antitumor activity with high potential to stop the proliferation of cells. In general, benzothiazole derivatives were more active in comparison to benzimidazole derivatives. Antimicrobial activity was evaluated with Broth microdilution testing (according to CLSI (Clinical Laboratory Standards Institute) guidelines) on Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus. Additionally, Saccharomyces cerevisiae was included in testing as a eukaryotic model organism. Compounds 5, 6, 8, 9 and 15 showed the most promising antibacterial activity. In general, the compounds showed antitumor activity, higher in 2D assays in comparison with 3D assays, on all three cell lines in both assays. In natural conditions, compounds with such an activity profile (less toxic but still effective against tumor growth) could be promising new antitumor drugs. Some of the tested compounds showed antimicrobial activity. In contrast to ctDNA, the presence of nitro group or chlorine in selected furane-benzothiazole structures did not influence the binding mode with AT-DNA. All compounds dominantly bound inside the minor groove of AT-DNA either in form of monomers or dimer and higher-order aggregates. 相似文献
64.
Manfredo Hörner Gelson Manzoni de Oliveira Janaina Sartori Bonini Herton Fenner 《Journal of organometallic chemistry》2006,691(4):655-658
3-(2-fluorophenyl)-1-(3-nitrophenyl)triazene reacts with mercury(II) acetate in tetrahydrofuran in the presence of 2,2′-bipyridilamine to give yellow crystalline blocks of polymeric {HgII[NNN(PhR)2]2}n (R = NO2, F). The new triazenide complex belongs to the triclinic space group . In a molecule of {HgII[NNN(PhR)2]2} two deprotonated 1,3-diaryl-substituted triazenide ligands are coordinated in an opposite way to one Hg(II) ion by means of primary and secondary bonds. The Hg(II) ions are placed on the inversion centers of translation operated {Hg[NNN(PhR)2]2} moieties which are stacked along the crystallographic a-axis forming infinite unidimensional chains linked through metalocene alike Hg-η2,η2-arene π-interactions. 相似文献
65.
Gelson Perin Samuel R. Mendes Márcio S. Silva Eder J. Lenardão Raquel G. Jacob Paulo C. dos Santos 《合成通讯》2013,43(18):2587-2595
A simple, clean, and efficient solvent‐free protocol was developed for hydrochalcogenation of 3‐organyl‐3‐butyn‐2‐ones with phenylchalcogenolate (Se, Te, S) anions generated in situ from the respective diphenyl dichalcogenide using alumina‐supported sodium borohydride (Se, Te) or commercially available (S). This efficient and improved method is general and furnishes the (Z)‐β‐phenylchalcogeno‐α,β‐unsaturated ketones in good yield with higher selectivity compared with those that use organic solvent and an inert atmosphere. The use of microwave (MW) irradiation facilitates the procedure and accelerates the reaction. 相似文献
66.
Ernesto Schulz Lang Gelson Manzoni de Oliveira Gabriela Nanci Ledesma 《无机化学与普通化学杂志》2005,631(8):1524-1527
[PhTe]2 and [(β‐naphthyl)Te]2 react with iodine and tetraethylammonium iodide in toluene/methanol to give (Et4N)[PhTeI4] and (Et4N)[(β‐Naphthyl)TeI4]. The complexes were analysed by single crystal X‐ray diffraction affording the centrosymmetric monoclinic space group P21/c. In the novel compounds only anionic interactions of the types Te···I and I···I take place, cation‐anion effective contacts do not occur. Both anions [PhTeI4] and [(β‐naphthyl)TeI4] exhibit square pyramidal coordination at tellurium, with the iodine atoms in the basal positions and the organic groups apical. The tellurium centers achieve an octahedral coordination in the whole lattices through Te···I secondary bonds with the adjacent ionic species. Only the Te–I‐ and I–I‐secondary bonds behave as structure‐forming interactions in the self‐organization of the supramolecular anionic gatherings. New evidences show that for organyltellurates (Q)[PhTeX4] (Q = protonated amines, amides or amino acids; X = Cl, Br, I), NH···X hydrogen bondings are able to hinder the anionic halogen‐halogen secondary interactions. In case of the more frequent I···I interactions, they have been observed only in the absence of NH···I hydrogen bonds. 相似文献
67.
Eder J. Lenardão Samuel R. Mendes Gelson Perin Raquel G. Jacob 《Tetrahedron letters》2006,47(42):7439-7442
A general and easy method for the synthesis of several selenonium and telluronium salts is described. These compounds are acidic liquids at room temperature and were obtained in excellent yields. Phenyl butyl ethyl selenonium tetrafluoroborate was employed in the hetero-Diels-Alder cyclization of aryl imines derived from citronellal, affording octahydroacridines in good yields. 相似文献
68.
Cd(dmpymt)2 reacts with CdCl2, CdBr2·4H2O, CdI2, 2,2′-bipyridine and 1,10-phenanthroline to give the dimeric chelates [Cd(dmpymt)(bpy)Cl]2 and [Cd(dmpymt)(phen)Cl]2, as well as the tri-nuclear complexes [Cd3(dmpymt)4(bpy)2Br2] and [Cd3(dmpymt)4(bpy)2I2] (dmpymtH = 4,6-dimethylpyrimidine-2-thione; bpy = 2,2′-bipyridine; phen = 1,10-phenantroline). In all complexes the Cd(II) centers present the coordination number six. The new compounds are examples of the managing of the final aggregation state of thiolate metal complexes by introducing co-ligands to block specific coordination sites of the metal center. 相似文献
69.
Gelson Perin Raquel G. Jacob Francisco de Azambuja Eder J. Lenardão 《Tetrahedron letters》2006,47(6):935-938
We present here the reaction of diphenyl dichalcogenides (Se and Te) with propargyl alcohols using alumina supported sodium borohydride under solvent-free conditions. This efficient and improved method is general and furnishes the corresponding vinyl chalcogenide preferentially with a Z configuration. We also observed that when the same protocol was applied to phenyl acetylene, the (E)-bis-organochalcogen alkenes were obtained in good yields and high selectivity. The use of MW irradiation facilitates the procedure and accelerates the reaction. 相似文献
70.
Renata A. Balaguez Vanessa Gentil RicordiCamilo S. Freitas Gelson PerinRicardo F. Schumacher Diego Alves 《Tetrahedron letters》2014
We describe here a simple and catalyst-free method to synthesize diaryl selenides by reaction of arenediazonium tetrafluoroborate salts with arylselenols, generated in situ by using diaryl diselenides and hypophosphorous acid (H3PO2), using THF as solvent. This is a direct nucleophilic aromatic substitution (SNAr) reaction performed with diaryl diselenides and arenediazonium salts bearing electron-withdrawing and electron-donating groups affording the corresponding diaryl selenides in moderated to good yields. 相似文献