Síntesis e índices de reactividad de triazoles derivados de lactosa y las xantinas teofilina y teobromina

Mediante un sistema de reacción de cicloadición (3+2) regioselectiva, ha sido posible unir mediante una estructura principal de triazol a los grupos tipo carbohidrato –lactosa– y a los grupos derivados de la familia xantina – teobromina y teofilina– para obtener la síntesis del producto correspondiente. Se espera que este tipo de moléculas presenten actividad como inhibidores de la corrosión. Para su estudio y caracterización hemos usado los índices de reactividad globales basados en la Teoría de Funcionales de la Densidad (TFD) que han llegado a ser una poderosa herramienta para el estudio de la reactividad de compuestos orgánicos. Se muestran los siguientes parámetros como EHOMO, ELUMO, GAP, la dureza y el momento dipolar como indicadores del comportamiento inhibidor de la corrosión de las moléculas sintetizadas.Through a regioselective cycloaddition (3+2) reaction system, it has been possible to link the carbohydrate-lactose- like groups and the groups derived from the xanthine-theobromine and theophylline-family through a triazole structure corresponding product. It is expected that this type of molecules present activity as corrosion inhibitors. For its study and characterization, we have used the global reactivity indices based on the Theory of Density Functionalists (TFD) that have become a powerful tool for the study of the reactivity of organic compounds. The following parameters are shown as EHOMO, ELUMO, GAP, hardness and dipole moment as indicators of the corrosion inhibitory behavior of synthesized molecules

Síntesis de lactosa-triazol-teofilina

Es conocido, que la combinación de triazoles con un fragmento carbohidrato produce moléculas híbridas con potencial actividad biológica. En este trabajo se presenta el diseño y síntesis un nuevo glicoconjugado lactosa-1,2,3-triazol que contiene un fragmento de teofilina como sustituyente. Los triazoles fueron preparados fácilmente mediante una reacción de cicloadición [3 + 2] catalizada por un hidróxido doble laminar (HDL) de Cu/Al calcinado, empleando como materiales de partida la 1- azidolactosa y el derivado propargilado de la teofilina. Los nuevos híbridos carbohidrato-triazol-xantina fueron caracterizados por espectroscopía de infrarrojo (IR) y resonancia magnética nuclear de una y dos dimensiones (RMN).It is known that the combination of triazoles with a carbohydrate fragment produces hybrid molecules with potential biological activity. In this work, we present the design and synthesis of a new lactose-1,2,3-triazole glycoconjugate containing a theophylline moiety as a substituent. Triazoles were easily prepared by using a [3 + 2] cycloaddition reaction catalyzed by a calcined double laminar hydroxide (HDL) of Cu/Al, using 1-azidolactose and the propargylated derivatives of theophylline as starting material. The new carbohydrate-triazol-xanthine hybrids were adequately characterized by infrared (IR) spectroscopy and one- and two-dimensional nuclear magnetic resonance (NMR)

Experimental and Theoretical Studies on Acid Corrosion Inhibition of API 5L X70 Steel with Novel 1-N-α-d-Glucopyranosyl-1H-1,2,3-Triazole Xanthines

A series of novel 1-N-α-d-glucopyranosyl-1H-1,2,3-triazole xanthines was synthesized from azido sugars (glucose, galactose, and lactose) and propargyl xanthines (theophylline and theobromine) using a typical copper (I)-catalyzed azide–alkyne 1,3-dipolar cycloaddition. The corrosion inhibition activities of these new carbohydrate-xanthine compounds were evaluated by studying the corrosion of API 5 L X70 steel in a 1 M HCl medium. The results showed that, at 10 ppm, a 90% inhibition efficiency was reached by electrochemical impedance spectroscopy. The inhibitory efficiency of these molecules is explained by means of quantum chemical calculations of the protonated species with the solvent effect, which seems to better represent the actual situation of the experimental conditions. Some quantum chemical parameters were analyzed to characterize the inhibition performance of the tested molecules