RESUMO
Abstract A new Cu(I) complex constructed by reaction of trithiocyanuric acid (ttc) and copper(II) perchlorate hexahydrate has been successfully synthesized by a slow sedimentation method in a DMF solvent at room temperature. The molecular structure of the compound was elucidated by MALDI-TOF MS, UV-Vis and FTIR spectroscopy, DSC-TGA analysis and magnetic susceptibility measurement. The proposed structure was corroborated by a computational study carried out with the Gaussian09® and AIMAII® programs using the RB3LYP hybrid DFT functional with both 6-31G and Alhrich-TZV basis sets. The calculated vibrational frequencies values were compared with experimental FTIR values. Photophysical properties of the synthesized complex were evaluated by UV-Visible spectroscopy and compared with computed vertical excitation obtained from TDDFT. The theoretical vibrational frequencies and the UV-Vis spectra are in good agreement with the experimental values. Additionally, the Frontier Molecular Orbitals (HOMO - LUMO) and the Molecular Electrostatic Potential of the complex was calculated using same theoretical approximation. The results showed the interaction between three coordinated ligand atoms and the Cu(I) ion.
Resumen Un nuevo complejo de Cu(I) elaborado por la reacción de ácido cianúrico (ttc) y perclorato de cobre(II) hexahidrato se sintetizó exitosamente por medio de un método lento de sedimentación en un solvente de DMF a temperatura ambiente. La estructura molecular del compuesto se determinó utilizando MS de MALDI-TOF, la espectroscopia de UV-VIS y de FTIR, el análisis de DSC-TGA y el análisis magnético de susceptibilidad. La estructura propuesta se corroboró por medio de un estudio computacional usando los programas Gaussian09® y AIMAII®, utilizando el híbrido RB3LYP DFT con los equipos 6-31G y Alhrich-TZV. Se compararon los valores calculados de las frecuencias vibracionales con los valores experimentales de FTIR. Se evaluaron las características fotofísicas del complejo sintetizado usando espectroscopia UV-visible y se compararon con la vibración vertical obtenida de TDDFT. Las frecuencias teóricas vibracionales y los espectros UV-VIS coinciden con los valores experimentales. Además, se calcularon las órbitas moleculares (HOMO - LUMO) y el potencial electrostático molecular del complejo usando la misma aproximación teórica. Los resultados demostraron la interacción entre tres receptores de átomos coordinados y el ion del Cu(I).
Resumo Um novo complexo de Cu(I) elaborado pela reação de ácido cianúrico (ttc) e perclorato de cobre (II) hexahidratado foi sintetizado de maneira exitosa por meio de um método lento de sedimentação em um solvente de DMF a temperatura ambiente. A estrutura molecular do composto se determinou utilizando MALDI-TOF, espectroscopia de UV-VIS e FTIR, DSC-TGA e análise magnético de susceptibilidade. A estrutura proposta se corroborou por meio de um estudo computacional usando os programas Gaussian09® e AIMAII®, utilizando o híbrido RB3LYP DFT com os equipamentos 6-31G e Alhirich-TZV. Se compararam os valores calculados das frequências vibracionais com os valores experimentais de FTIR. Se avaliaram as características fotofísicas do complexo sintetizado utilizando espectroscopia UV-VIS e se compararam com a vibração vertical obtida de TDDFT. As frequências teóricas vibracionais e os espectros UV-VIS coincidem com os valores experimentais. Além disso, se calcularam as órbitas moleculares (HOMO - LUMO) e o potencial eletrostático molecular do complexo utilizando a mesma aproximação teórica. Os resultados demonstraram a interação entre três receptores de átomos coordenados e o íon de Cu(I).
Assuntos
Estrutura Molecular , Análise Espectral , Complexos de CoordenaçãoRESUMO
In this study we evaluated the antioxidant and antihyperglycemic activity in vitro of the extracts obtained with solvents: hexane, ethyl acetate and methanol, of the medicinal plant Oreocallis grandiflora (cucharillo), collected in the Saraguro indian community of the province Loja, southern Ecuador. The antioxidant activity was evaluated by the tests: DPPH, FOLIN-CIOCALTEU and beta-CLAMS, while the antihyperglycemic activity was determined by inhibition assay á-amylase and alpha-glucosidase. The samples were diluted to different concentrations and the reading was performed in a UV spectrophotometer, using as positive control á-tocopherol for DPPH and Folin-ciocalteu test, trolox for beta-CLAMS test, and Glucobay® for testing alpha-amylase and alpha-glucosidase.The results are expressed as IC50, these show that the methanol extract of Oreocallis grandiflora has inhibitory effect on alpha-amylase, the IC50 is 109 ug/ml, compared to 126 ug/ ml of Glucobay®. It also shows inhibitory effect on á-glucosidase, the IC50 is 3 ug/ml compared to 1316 ug/ml of Glucobay®. It also shows antioxidant activity, its IC50 is 15 ug/ml compared to 5 ug/ml of á-tocopherol.
En el presente trabajo se evaluó la actividad antioxidante y antihiperglucemiante in vitro de los extractos obtenidos con los solventes: hexano, acetato de etilo y metanol, de la planta medicinal Oreocallis grandiflora (cucharillo), recolectada en la comunidad indígena de Saraguro en la provincia de Loja, al sur del Ecuador. La actividad antioxidante fue evaluada a través de los ensayos: DPPH, FOLIN-CIOCALTEU y beta-CLAMS, mientras que la actividad antihiperglucemiante fue determinada por el ensayo de inhibición de alfa- amilasa y alfa-glucosidasa. El extracto metanólico de Oreocallis grandiflora presenta efecto inhibitorio sobre la enzima alfa-amilasa, su concentración inhibitoria (CI50) es de 109 ug/ml, frente a 126 ug/ml del control positivo Glucobay®. Además, muestra efecto inhibitorio sobre la enzima alfa-glucosidasa, su concentración inhibitoria (CI50) es de 3 ug/ml, frente a 1316 ug/ml del Glucobay®. Muestra también actividad antioxidante, su concentración inhibitoria (CI50) es de 15 ug/ml, frente a 5 ug/ml del alfa-tocoferol.