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Una estructura plegada y secundaria en oligómeros de crecimiento gradual de aromáticos covalentemente unidos y
Wei Zhang1, Dana Horoszewski, John Decatur
1Department of Chemistry, Columbia University, New York, New York 10027, USA.
Journal of the American Chemical Society
|April 17, 2003
Resumen
Los investigadores desarrollaron nuevos oligómeros plegados utilizando enlaces en forma de C y cadenas laterales específicas. Este robusto motivo plegable, impulsado por enlaces de hidrógeno y apilamiento de pi, permite la formación de estructuras secundarias incluso en dímeros.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Química orgánica es la química orgánica.
- La ciencia de los polímeros es la ciencia de los polímeros.
Sus antecedentes:
- Los oligómeros son moléculas compuestas de unas pocas unidades repetitivas.
- Lograr estructuras secundarias predecibles en oligómeros sintéticos sigue siendo un desafío.
- Los sistemas aromáticos superpoblados ofrecen posibilidades estructurales únicas.
Objetivo del estudio:
- Desarrollar un método general para crear una nueva clase de oligómeros plegados.
- Investigar el papel de los enlaces y las cadenas laterales en la estructura secundaria de los oligómeros.
- Para establecer un motivo de plegado robusto basado en interacciones no covalentes.
Principales métodos:
- Adhesión covalente de las subunidades aromáticas superpobladas.
- Utilizando enlaces en forma de C para preorganizar las hebras.
- Empleando cadenas laterales tris ((dodeciloxi) fenetil y tert-butilo para la solubilidad y el control estructural.
- Análisis de la estructura secundaria en solución utilizando espectroscopia de RMN (1) H unidimensional y bidimensional.
Principales resultados:
- Demostró la formación de conformaciones columnares bien definidas en solución.
- Mostró el papel crítico de las cadenas laterales para permitir la estructura secundaria.
- Logró solubilidad y evitó la agregación en oligómeros con cadenas laterales específicas.
- Confirmó la robustez del motivo plegable, observando la estructura secundaria incluso en dímeros.
Conclusiones:
- Se ha creado una nueva clase de oligómeros plegados con estructuras secundarias predecibles.
- Los enlaces en forma de C y las cadenas laterales cuidadosamente elegidas son esenciales para dirigir el plegado.
- La sinergia entre los enlaces de hidrógeno y el pi-stacking proporciona un robusto mecanismo de plegado.
- Este trabajo abre caminos para el diseño de complejas arquitecturas supramoleculares.
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