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La cadena lateral peptoide de triazolio de clic: un fuerte inductor de cis-amida que permite la diversidad química
Cécile Caumes1, Olivier Roy, Sophie Faure
1Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, F-63000 Clermont-Ferrand, France.
Journal of the American Chemical Society
|May 23, 2012
Resumen
Los investigadores desarrollaron una nueva cadena lateral de triazolio para los peptoides, mejorando el control sobre las estructuras plegadas. Esta innovación preserva la diversidad de la cadena lateral al tiempo que promueve la conformación cis deseada, un avance significativo en la química peptidomimética.
Área de la Ciencia:
- Los peptidomiméticos y la química supramolecular.
- Química orgánica y biología química.
Sus antecedentes:
- El logro de estructuras peptoides plegadas homogéneas y discretas se basa en el control del isomerismo cis / trans en las amidas terciarias de la columna vertebral.
- Los métodos actuales a menudo limitan la diversidad de la cadena lateral, una ventaja clave de los peptoides.
- Los peptoides son valiosos peptidomiméticos con amplias aplicaciones.
Objetivo del estudio:
- Introducir una nueva cadena lateral de tipo triazolio cargada positivamente para la síntesis de peptoides.
- Evaluar la capacidad de la cadena lateral para inducir la conformación cis sin sacrificar la diversidad.
- Para dilucidar el mecanismo detrás del efecto de dirección cis.
Principales métodos:
- Síntesis y caracterización de sistemas modelo de dipeptoides de N-acetamida con la cadena lateral de triazolio.
- Espectroscopia de RMN para determinar las relaciones de isomerismo cis/trans (K(cis/trans)) en varios disolventes.
- Optimización de la geometría computacional y análisis orbital de enlaces naturales.
- Experimentos de NOESY para conocimientos estructurales.
Principales resultados:
- La cadena lateral de triazolio demostró una capacidad superior de inducción de cis, logrando los mejores valores de K (cis/trans) reportados.
- Este efecto se observó tanto en disolventes apróticos como en proticos.
- Los datos computacionales y experimentales apoyaron un modelo que involucra n → π*(Ar) deslocalización electrónica y enlace de hidrógeno cooperativo.
Conclusiones:
- La nueva cadena lateral de triazolio controla efectivamente el isomerismo cis/trans en los peptoides, preservando la diversidad de la cadena lateral.
- El mecanismo de dirección cis implica una combinación de deslocalización electrónica y enlace de hidrógeno.
- Este hallazgo ofrece una nueva estrategia para diseñar estructuras peptoides dobladas con precisión para diversas aplicaciones.
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