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Efectos de largo alcance en la captura y liberación de un huésped quiral por una cápsula molecular helicoidal
Yann Ferrand1, Nagula Chandramouli, Amol M Kendhale
1Université Bordeaux, CBMN, UMR 5248, Institut Européen de Chimie Biologie, 2 rue Escarpit, 33607 Pessac, France.
Journal of the American Chemical Society
|June 14, 2012
Resumen
Las cápsulas moleculares hechas de aminoácidos aromáticos se unen selectivamente al ácido tartárico. El alargamiento de estas cápsulas alteró inesperadamente las tasas de unión y liberación del huésped, revelando complejos mecanismos de unión remota.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Química orgánica es la química orgánica.
- Biología Química Biología química.
Sus antecedentes:
- Las cápsulas moleculares plegadas helicoidalmente ofrecen propiedades de unión únicas.
- Las secuencias de oligoamidas de aminoácidos aromáticos pueden formar estructuras helicoidales estables.
- Comprender las interacciones huésped-huésped es crucial para el reconocimiento molecular.
Objetivo del estudio:
- Para sintetizar e investigar cápsulas moleculares plegadas helicalmente para la unión del ácido tartárico.
- Para explorar el impacto de la elongación de la hélice en la estabilidad de la cápsula y la afinidad de unión.
- Para aclarar los mecanismos que rigen las tasas de enlace y liberación de invitados.
Principales métodos:
- Síntesis de cápsulas moleculares de oligoamida plegadas en forma de hélice.
- (1) RMN H, cristalografía de rayos X y dicroísmo circular para el análisis estructural y de unión.
- Modelado molecular y RMN 2D-EXSY para investigar la dinámica de intercambio de invitados.
Principales resultados:
- Las cápsulas demostraron una alta afinidad y diastereoselectividad para el ácido tartárico en disolventes orgánicos.
- El alargamiento de la hélice aumentó la estabilidad general de la hélice, pero no la estabilidad del complejo huésped-huésped.
- Las tasas de cambio de los huéspedes mostraron una tendencia no monótona con el aumento de la longitud de la hélice, primero aumentando y luego disminuyendo.
Conclusiones:
- El alargamiento de la hélice impacta significativamente los eventos de unión remota en las cápsulas moleculares.
- El estudio revela complejos mecanismos de unión y liberación influenciados por la longitud de la hélice.
- Los hallazgos proporcionan información sobre el diseño de cápsulas moleculares con cinética de unión sintonizable.
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