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Un imitación de la enzima pirrol que restringe dos oxoaniones en estrecha proximidad
Qing He1, Michael Kelliher1, Steffen Bähring1,2
1Department of Chemistry, The University of Texas at Austin , 105 East 24th Street-A5300, Austin, Texas 78712-1224, United States.
Journal of the American Chemical Society
|May 12, 2017
Resumen
Una nueva molécula similar a una cápsula, el bis-calix[4]pirrol 1, puede unirse simultáneamente a dos aniones, incluido el fosfato de dihidrógeno, el sulfato y el pirofosfato. Este reconocimiento dual de aniones fue confirmado utilizando varios métodos espectroscópicos y cristalográficos.
Área de la Ciencia:
- Química supramolecular
- Química entre anfitrión y huésped
- Reconocimiento de aniones
Sus antecedentes:
- Los macrociclos de calixpirrol son plataformas versátiles para el reconocimiento molecular.
- El diseño de receptores para la unión simultánea de múltiples aniones es un desafío significativo.
Objetivo del estudio:
- Para sintetizar y caracterizar una gran cápsula como el bis-calix[4]receptor pirrol.
- Investigar la capacidad del receptor para albergar múltiples aniones simultáneamente.
- Explorar las bases estructurales y electrónicas de la unión de aniones duales.
Principales métodos:
- Síntesis del receptor de bis-calix[4]pirrol 1.
- Análisis espectroscópicos (1H RMN, frente a los rayos UV).
- Calorimetría por titulación isotérmica (ITC).
- Difracción de rayos X de un solo cristal.
- Cálculos de la Teoría Funcional de la Densidad (DFT).
Principales resultados:
- El receptor 1 acogió con éxito dos aniones de fosfato de dihidrógeno en solución.
- El receptor también se une a dos aniones de sulfato, formando un dímero en estado sólido y solución.
- El receptor 1 demostró la capacidad de acomodar dos aniones de pirofosfato trianiónico.
- Los estudios estructurales y computacionales aclararon los modos e interacciones de unión.
Conclusiones:
- El bis-calix[4]pirrol 1 exhibe una notable capacidad para la unión simultánea de aniones duales.
- La gran cavidad y las características estructurales del receptor facilitan el reconocimiento de varios polianiones.
- Este trabajo avanza en el diseño de moléculas de huésped sofisticadas para desafíos complejos de reconocimiento de aniones.
![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
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