ASYMMETRIC 1,3-DIPOLAR CYCLOADDITION REACTIONS OF AZOMETHINE IMINES WITH ACROLEIN CATALYZED BY L-PROLINE AND ITS DERIVATIVES

1,3-Dipolar cycloadditions between acrolein and various N,N'-cyclic azomethine imines in the presence of L-proline and its derivatives as organocatalysts were investigated. Reactions that were catalyzed by (S)-indline-2-carboxylic acid (30 mol%) in CHCl3/MeOH 97:3 (v/v) showed high exo-selectivities (exolendo 91:9 similar to 99:1) and enantioselectivities (75 similar to 98% ee). In contrast, reactions catalyzed by L-proline (30 mol%) under similar conditions favored the endo-cycloadduct (83:27 similar to 99:1) with modest to good enantioselectivities (31 similar to 83% ee). Based on our studies, the diastereoselective mechanism of the L-proline-catalyzed reaction was found to involve the isomerization of the exo- to the endo-cycloadduct in the presence of L-proline.ArticleHETEROCYCLES. 81(7):1669-1688 (2010)journal articl

Functionalized coatings by electrospinning for anti-oxidant food packaging

The development of advanced formulations used for food packaging applications, which behave as protection or preservation materials and improve consumers’ health offers a route to reduced food wastage. The present study deals with investigations on the possibility of obtaining functionalized coatings by electrospinning of poly(ɛ-caprolactone), a synthetic biodegradable polymer together with vitamin E (α-tocopherol), selected as plant-based phenolic antioxidant. In this approach electrospinning allows the production of high surface area materials and thus offering an increased antioxidant activity. The electrospun fibres of poly(ɛ-caprolactone)/vitamin E were obtained, studied and their antioxidant properties were evaluated by measuring the fibre reactivity with 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. The potential for extending the shelf-life of food products by using this approach is discussed

Gustavo Bolívar : el hombre de las narcotelenovelas

El presente artículo reseñará la principal obra del creador de la narcotelenovela en Colombia, Gustavo Bolívar, quien desde su primer trabajo para la televisión sobre el tema del narcotráfico, Sin tetas no hay paraíso, no dejó de revolucionar el género a través de la escritura de sus siguientes obras: Tres Caínes y cada una de las temporadas de El capo.El present article ressenyarà la principal obra del creador de la narcotelenovel·la a Colòmbia, Gustavo Bolívar, qui des del seu primer treball per la televisió sobre el tema del narcotràfic, com és Sin tetas no hay paraíso, no va deixar de revolucionar el gènere a través de l'escriptura de les seves següents obres, com van ser Tres Caínes i cadascuna de les temporades de El capo.This article focuses on Gustavo Bolívar's work as a creator of the narcotelenovela, genre born in Colombia. Since his first work, Sin tetas no hay paraíso (Without breasts there is no paradise), he revolutions the gener with the writing of Tres Caínes (Three Caínes) and with the three seasons of El Capo