37 research outputs found
Synthesis of Diiodo-Functionalized Benzo[b] furans via Electrophilic Iodocyclization
An electrophilic iodocyclization reaction involving alkynylated 2-iodoanisoles and molecular iodine in the presence of sodium bicarbonate was developed and diiodo-functionalized benzo[b] furans were obtained in yields from 45 to 99%.Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Fundacao de Apoio ao Desenvolvimento do Ensino, Ciencia e Tecnologia do Estado de Mato Grosso do Sul (FUNDECT)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Fundacao Univ Fed Grande Dourados, Grp Pesquisa Sintese & Caracterizacao Mol MS, Rua Joao Rosa Goes,1761, BR-79825070 Dourados, MS, BrazilUniv Fed Sao Paulo, Inst Ciencias Ambientais Quim & Farmaceut, Rua Prof Artur Riedel,275, BR-09972270 Diadema, SP, BrazilUniv Fed Sao Paulo, Inst Ciencias Ambientais Quim & Farmaceut, Rua Prof Artur Riedel,275, BR-09972270 Diadema, SP, BrazilWeb of Scienc
Palladium- and copper-catalyzed highly selective mono-coupling between 2,6-diiodoanisoles and terminal alkynes in the production of alkynylated anisoles as potential precursors of benzo[b]furans
The coupling reaction between 2,6-diiodoanisoles and terminal alkynes using Pd(PPh3)2Cl2 and CuI as catalysts and diisopropylamine as base in toluene at room temperature for 12 h produced selectively alkynylated 2-iodoanisoles, in good to excellent yields (52-95%), which are useful building blocks with potential application in the synthesis of functionalized benzo[b]furans.A reação de acoplamento entre 2,6-diiodoanisóis e alcinos terminais usando Pd(PPh3)2Cl2 e CuI como catalisadores e diisopropilamina como base em tolueno a temperatura ambiente por 12 h produziu seletivamente 2-iodoanisóis aquinilados, em rendimentos de bons a excelentes (52-95%), os quais são blocos de construção úteis com potencial aplicação na síntese de benzo[b]furanos funcionalizados.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundacao de Apoio ao Desenvolvimento do EnsinoCiencia e Tecnologia do Estado de Mato Grosso do Sul (FUNDECT)Universidade Federal de São Paulo (UNIFESP) Departamento de Ciências Exatas e da TerraUniversidade Federal da Grande Dourados Faculdade de Ciências Exatas e TecnologiaUNIFESP, Depto. de Ciências Exatas e da TerraSciEL
Unexpected Formation of Bis(hydrazinecarboximidamide) via Ultrasound Promoted Rearrangement of Epoxy Ketone
An efficient synthesis of aromatic pyrazoles via cyclocondensation of epoxy chalcones with hydrazine is reported. When aminoguanidine hydrochloride is the dinucleophilic specie the reaction leads to a mixture of amidino pyrazole and a minor amount (15%) of an interesting co-product identified as 2,2'-(1,3-diphenylpropane-1,2-diylidene)bis(hydrazinecarboximidamide) dihydrochloride by X-ray diffraction and NMR. A plausible mechanism for the co-product formation via rearrangement of the epoxy chalcone into 1,2-diketone followed by the condensation with aminoguanidine reaction is proposed.
DOI: http://dx.doi.org/10.17807/orbital.v9i3.97
Ultrasound-Promoted Synthesis of 3-(Thiophen-2-yl)-4,5-dihydro-1H-pyrazole-1carboximidamides and Anticancer Activity Evaluation in Leukemia Cell Lines
3-(Thiophen-2-yl)-4,5-dihydro-1H-pyrazole-1-carboximidamides were efficiently prepared through a cyclocondensation of thiophenylchalcones with aminoguanidine hydrochloride under ultrasonic conditions in the presence of KOH and ethanol as a green solvent in short reaction times (15-35 min) and good yields (62-95%). All compounds produced were evaluated against the human Jurkat and RS411 acute lymphoblastic leukemia cell lines of T- and B-cell origin, respectively, and the K562 myelogenous leukemia cell line. Six compounds presented half maximal inhibitory concentration (IC50) values around 15 mu mol L-1 and five compounds presented IC50 values around 40 mu mol L-1 for at least one of the three cell lines analyzed. One compound was not significantly cytotoxic, presenting IC50 value > 100 mu mol L- 1.Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Fundacao de Apoio ao Desenvolvimento do Ensino, Ciencia e Tecnologia do Estado de Mato Grosso do Sul (FUNDECT)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)FAPESPCNPqFundacao Univ Fed Grande Dourados, Grp Pesquisa Sintese & Caracterizacao Mol MS, Rua Joao Rosa Goes 1761, BR-79825070 Dourados, MS, BrazilUniv Estadual Campinas, Inst Biol, Dept Genet & Biol Mol, Rua Monteiro Lobato 255, BR-13083970 Campinas, SP, BrazilCtr Infantil Boldrini, Mol Biol Lab, Rua Dr Gabriel Porto 1270, BR-13083210 Campinas, SP, BrazilUniv Fed Sao Paulo, Dept Ciencias Exatas & Terra, Rua Prof Artur Riedel 275, BR-09972270 Diadema, SP, BrazilUniv Fed Pelotas, Ctr Ciencias Quim Farmaceut & Alimentos, Lab Lipid & Bioorgan, Campus Univ, BR-96001900 Pelotas, RS, BrazilUniv Estadual Mato Grosso do Sul, Rua Emilio Mascolli 275, BR-79950000 Navirai, MS, BrazilUniv Fed Sao Paulo, Dept Ciencias Exatas & Terra, Rua Prof Artur Riedel 275, BR-09972270 Diadema, SP, BrazilCNPq: 483021/2013-0FUNDECT: 0180/12FAPESP: 12/12802-1Web of Scienc
Synthesis of 6-(2-furyl) and 6-(2-thienyl)-4-trifluoromethylpyrimidinones and pyrimidines from 4-(2-heteroaryl)-4-methoxy-1,1,1-trifluoro-3-buten-2-ones
The synthesis of biheterocyclic systems 6-(2-furyl)-pyrimidines and 6-(2-thienyl)pyrimidines in reasonable yields (50-67%), two 6-(2-heteroaryl)-4-trifluoromethyl-2-(1H)pyrimidinones (2a,b) and a series of ten 6-(2-heteroaryl)-4-trifluoromethylpyrimidines (3a,b 7a,b) from the cyclocondensation of 1,1,1-trifluoro-4-(2-heteroaryl)-4-methoxy-3-buten-2-ones with urea and amidines is reported. Structures of all compounds have been elucidated by elemental analysis, mass spectrometry and ¹H, 13C NMR measurements. The ¹H and 13C NMR data are systematically reported. The X-ray diffraction data for monocrystal from 2-amino-4trifluoromethyl-6-(thien-2-yl)-pyrimidine (5b) are reported
Dimeric Self-assembling via Hydrogen Bonding and Emissive Behavior of a New Copper (I) Complex
This work describes the synthesis, structural characterization and emissive behavior of a new copper (I) complex based on 1-thiocarbamoyl-5-(4-methoxiphenyl)-3-phenyl-4,5-dihydro-1H-pyrazole ligand. A dimeric self-assembling via hydrogen bonding was determined by analyzing the short contacts present in the solid-state structure by means of X-ray crystallography. The spectroscopic properties were determined using UV-Vis and fluorescence experiments and an interesting behavior as bluish luminescence was assigned mainly to the mixed (MLCT + IL) electronic transitions of the Cu(I)d10 ® (S=C–Nligand) type. The complete characterization of the new copper (I) complex also included elemental analyses and IR spectroscopy.
DOI: http://dx.doi.org/10.17807/orbital.v9i1.95
Efficient synthesis of new 1-[Alkyl(aryl)]-5-(3,3,3-trihalo-2-oxopropylidene)pyrrolidin-2-ones
Reactions of methyl 4-methoxy-6-oxo-7,7,7-trihalo-4-heptenoates 1 and 2 with primary amines RNH2, where R = PhCH2, PhCH2CH2, Ph, 4-MeC6H4, 4-MeOC6H4, 4-ClC6H4, 4-BrC6H4, 2-pyridyl, 5-methyl-3-isoxazolyl, 4-NH2C6H4 affording methyl 4-[alkyl(aryl)amino]-6-oxo-7,7,7-trihalo-4-heptenoates 3, 4, in good yields (57-95%), which suffer quantitative intramolecular cyclocondensation to produce 1-alkyl(aryl)-5-(2-oxo-3,3,3-trihalopropylidene)pyrrolidin-2-ones 5, 6, are reported. The structures of the isolated new products were assigned by means of ¹H,13C NMR measurements and mass spectrometry. The Z and E configuration of compounds 3d and 5b respectively were established from X-ray crystallography
Bio-inspired computation: where we stand and what's next
In recent years, the research community has witnessed an explosion of literature dealing with the adaptation of behavioral patterns and social phenomena observed in nature towards efficiently solving complex computational tasks. This trend has been especially dramatic in what relates to optimization problems, mainly due to the unprecedented complexity of problem instances, arising from a diverse spectrum of domains such as transportation, logistics, energy, climate, social networks, health and industry 4.0, among many others. Notwithstanding this upsurge of activity, research in this vibrant topic should be steered towards certain areas that, despite their eventual value and impact on the field of bio-inspired computation, still remain insufficiently explored to date. The main purpose of this paper is to outline the state of the art and to identify open challenges concerning the most relevant areas within bio-inspired optimization. An analysis and discussion are also carried out over the general trajectory followed in recent years by the community working in this field, thereby highlighting the need for reaching a consensus and joining forces towards achieving valuable insights into the understanding of this family of optimization techniques