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A concise synthesis of a highly substituted 6-(1H-benzimidazol-1-yl)-5-nitrosopyrimidin-2- amine: Synthetic sequence and the molecular and supramolecular structures of one product and two intermediates

Cobo, Justo; Vicentes, Daniel E.; Rodríguez, Ricaurte; Marchal, Antonio; Glidewell, Christopher (2018)

A concise and efficient synthesis of 6-benzimidazolyl-5-nitrosopyrimidines has been developed using Schiff base-type intermediates derived from N4-(2-aminophenyl)-6-methoxy-5-nitrosopyrimidine-2,4-diamine. 6-Methoxy-N4-{ ...
Conversion of 3-amino-4-arylamino-1H-isochromen- 1-ones to 1-arylisochromeno[3,4-d]- [1,2,3]triazol-5(1H)-ones: Synthesis, spectroscopic characterization and the structures of four products and one ring-opened derivative

Vicentes, Daniel E.; Romero, Andrea L.; Rodríguez, Ricaurte; Cobo, Justo; Glidewell, Christopher (2020)

An efficient synthesis of 1-arylisochromeno[3,4-d][1,2,3]triazol-5(1H)-ones, involving the diazotization of 3-amino-4-arylamino-1H-isochromen-1-ones in weakly acidic solution, has been developed and the spectroscopic ...
Obtención y purificación de compuestos relacionados a partir de Diclofenaco materia prima y la mediación catálitica de ácido y metales de transición (Cobre, Manganeso y Cobalto)

Pico González, Marcela (Bogotá : Universidad de Ciencias Aplicadas y Ambientales, 2012Facultad de CienciasQuímica, 2012)

Esta investigación busca obtener a través de síntesis química in-situ la modificación de la molécula del Diclofenaco a temperatura ambiente, en medio ácido y catalizada por los metales de transición: Cobre, Manganeso y ...
p-Methoxyphenol: A potent and effective scavenger for solid-phase peptide synthesis

Samacá, Jhoan; Velandia Bautista, Erika; Tabares, Luisa; Escamilla, Luis; Vanegas, Magnolia; Patarroyo, Manuel Elkin (2020)

During the final step of t-Boc/Bzl, solid-phase peptide synthesis (SPPS)-protecting groups from amino acids (aa) side chains must be removed from the target peptides during cleavage from the solid support. These reaction ...
Synthesis and in vitro antiproliferative activity of flavone and 6-hydroxyflavone oxime ethers derivatives

Díaz, John E.; Martinez, Diana C.; López, Lina V.; Mendez, Gina M.; Vera, Ricardo; Loaiza, Alix E. (2018)

Herein we report the synthesis of a series of O-alkyl oximes of flavone and 6-hydroxyflavone using a simple experimental protocol under solvent free conditions with yields up to 87%. Cytotoxicity of all compounds was ...

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A concise synthesis of a highly substituted 6-(1H-benzimidazol-1-yl)-5-nitrosopyrimidin-2- amine: Synthetic sequence and the molecular and supramolecular structures of one product and two intermediates
...
Cobo, Justo | 2018

A concise and efficient synthesis of 6-benzimidazolyl-5-nitrosopyrimidines has been developed using Schiff base-type intermediates derived from N4-(2-aminophenyl)-6-methoxy-5-nitrosopyrimidine-2,4-diamine. 6-Methoxy-N4-{2-[(4-methylbenzylidene)amino]phenyl}-5-nitrosopyrimidine-2,4-diamine, (I), and N4-{2-[(ethoxymethylidene)amino]phenyl}-6-methoxy-5-nitrosopyrimidine-2,4-diamine, (III), both crystallize from dimethyl sulfoxide solution as the 1:1 solvates C19H18N6O2·C2H6OS, (Ia), and C14H16N6O3·C2H6OS, (IIIa), respectively. The interatomic distances in these intermediates indicate significant electronic polarization within the substituted pyrimidine system. In each of (Ia) and (IIIa), intermolecular N-H…O hydrogen bonds generate centrosymmetric four-molecule aggregates. Oxidative ring closure of intermediate (I), effected using ammonium hexanitratocerate(IV), produced 4-methoxy-6-[2-(4-methylphenyl-1H-benzimidazol-1-yl]-5-nitrosopyrimidin-2-amine, C19H16N6O2, (II) [Cobo et al. (2018). Private communication (CCDC 1830889). CCDC, Cambridge, England], where the extent of electronic polarization is much less than in (Ia) and (IIIa). A combination of N–H…N and C–H…O hydrogen bonds links the molecules of (II) into complex sheets.

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Conversion of 3-amino-4-arylamino-1H-isochromen- 1-ones to 1-arylisochromeno[3,4-d]- [1,2,3]triazol-5(1H)-ones: Synthesis, spectroscopic characterization and the structures of four products and one ring-opened derivative
...
Vicentes, Daniel E. | 2020

An efficient synthesis of 1-arylisochromeno[3,4-d][1,2,3]triazol-5(1H)-ones, involving the diazotization of 3-amino-4-arylamino-1H-isochromen-1-ones in weakly acidic solution, has been developed and the spectroscopic characterization and crystal structures of four examples are reported. The molecules of 1-phenylisochromeno[3,4-d][1,2,3]triazol-5(1H)-one, C15H9N3O2, (I), are linked into sheets by a combination of C - H⋯N and C - H⋯O hydrogen bonds, while the structures of 1-(2-methylphenyl)isochromeno[3,4-d][1,2,3]triazol-5(1H)-one, C16H11N3O2, (II), and 1-(3-chlorophenyl)isochromeno[3,4-d][1,2,3]triazol-5(1H)-one, C15H8ClN3O2, (III), each contain just one hydrogen bond which links the molecules into simple chains, which are further linked into sheets by π-stacking interactions in (II) but not in (III). In the structure of 1-(4-chlorophenyl)isochromeno[3,4-d][1,2,3]triazol-5(1H)-one, (IV), isomeric with (III), a combination of C - H⋯O and C - H⋯π(arene) hydrogen bonds links the molecules into sheets. When compound (II) was exposed to a strong acid in methanol, quantitative conversion occurred to give the ring-opened transesterification product methyl 2-[4-hydroxy-1-(2-methylphenyl)-1H-1,2,3-triazol-5-yl]benzoate, C17H15N3O3, (V), where the molecules are linked by paired O - H⋯O hydrogen bonds to form centrosymmetric dimers.

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Obtención y purificación de compuestos relacionados a partir de Diclofenaco materia prima y la mediación catálitica de ácido y metales de transición (Cobre, Manganeso y Cobalto)
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Pico González, Marcela | 2012

Esta investigación busca obtener a través de síntesis química in-situ la modificación de la molécula del Diclofenaco a temperatura ambiente, en medio ácido y catalizada por los metales de transición: Cobre, Manganeso y Cobalto, purificando y caracterizando los compuestos obtenidos.

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p-Methoxyphenol: A potent and effective scavenger for solid-phase peptide synthesis
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Samacá, Jhoan | 2020

During the final step of t-Boc/Bzl, solid-phase peptide synthesis (SPPS)-protecting groups from amino acids (aa) side chains must be removed from the target peptides during cleavage from the solid support. These reaction steps involve hydrolysis with hydrogen fluoride (HF) in the presence of a nucleophile (scavenger), whose function is to trap the carbocations produced during SN1-type reactions. Five peptide sequences were synthesised for evaluating p-methoxyphenol effectiveness as a potent scavenger. After the synthesis, the resin–peptide was then separated into two equal parts to be cleaved using two scavengers: conventional reactive p-cresol (reported in the literature as an effective acyl ion eliminator) and p-methoxyphenol (hypothesised as fulfilling the same functions as the routinely used scavenger). Detailed analysis of the electrostatic potential map (EPM) revealed similarities between these two nucleophiles, regarding net atomic charge, electron density distribution, and similar pKa values. Good scavenger efficacy was observed by chromatography and mass spectrometry results for the synthesised molecules, which revealed that p-methoxyphenol can be used as a potent scavenger during SPPS by t-Boc/Bzl strategy, as similar results were obtained using the conventional scavenger.

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Synthesis and in vitro antiproliferative activity of flavone and 6-hydroxyflavone oxime ethers derivatives
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Díaz, John E. | 2018

Herein we report the synthesis of a series of O-alkyl oximes of flavone and 6-hydroxyflavone using a simple experimental protocol under solvent free conditions with yields up to 87%. Cytotoxicity of all compounds was evaluated against MDA-MB-231, PC-3, A-549 and MRC-5 cells. IC50 values for two compounds were determined to be in the range 28.7-47.8 μM against all tested cell lines. Oxime ethers derivatives showed IC50 values between 28.7 and 49.5 μM against MDA-MB-231, while the best activity was obtained for 6-hydroxyflavone with an IC50 of 3.4 μM against this cell line. Compounds containing the substituent hydroxyl at the position six of flavone system displayed the best antiproliferative activity over MDA-MB-231 cells, being necessary this group to improve the sensibility on this type of cells. The antiproliferative activity of 6-hydroxyflavone is drastically diminished when the carbonyl group of flavone is changed by an oxime ether.

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Browsing by Subject "Síntesis química"

A concise synthesis of a highly substituted 6-(1H-benzimidazol-1-yl)-5-nitrosopyrimidin-2- amine: Synthetic sequence and the molecular and supramolecular structures of one product and two intermediates ﻿

Conversion of 3-amino-4-arylamino-1H-isochromen- 1-ones to 1-arylisochromeno[3,4-d]- [1,2,3]triazol-5(1H)-ones: Synthesis, spectroscopic characterization and the structures of four products and one ring-opened derivative ﻿

Obtención y purificación de compuestos relacionados a partir de Diclofenaco materia prima y la mediación catálitica de ácido y metales de transición (Cobre, Manganeso y Cobalto) ﻿

p-Methoxyphenol: A potent and effective scavenger for solid-phase peptide synthesis ﻿

Synthesis and in vitro antiproliferative activity of flavone and 6-hydroxyflavone oxime ethers derivatives ﻿

Envíos recientes

A concise synthesis of a highly substituted 6-(1H-benzimidazol-1-yl)-5-nitrosopyrimidin-2- amine: Synthetic sequence and the molecular and supramolecular structures of one product and two intermediates

Conversion of 3-amino-4-arylamino-1H-isochromen- 1-ones to 1-arylisochromeno[3,4-d]- [1,2,3]triazol-5(1H)-ones: Synthesis, spectroscopic characterization and the structures of four products and one ring-opened derivative

Obtención y purificación de compuestos relacionados a partir de Diclofenaco materia prima y la mediación catálitica de ácido y metales de transición (Cobre, Manganeso y Cobalto)

p-Methoxyphenol: A potent and effective scavenger for solid-phase peptide synthesis

Synthesis and in vitro antiproliferative activity of flavone and 6-hydroxyflavone oxime ethers derivatives

A concise synthesis of a highly substituted 6-(1H-benzimidazol-1-yl)-5-nitrosopyrimidin-2- amine: Synthetic sequence and the molecular and supramolecular structures of one product and two intermediates

Conversion of 3-amino-4-arylamino-1H-isochromen- 1-ones to 1-arylisochromeno[3,4-d]- [1,2,3]triazol-5(1H)-ones: Synthesis, spectroscopic characterization and the structures of four products and one ring-opened derivative

Obtención y purificación de compuestos relacionados a partir de Diclofenaco materia prima y la mediación catálitica de ácido y metales de transición (Cobre, Manganeso y Cobalto)

p-Methoxyphenol: A potent and effective scavenger for solid-phase peptide synthesis

Synthesis and in vitro antiproliferative activity of flavone and 6-hydroxyflavone oxime ethers derivatives