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Síntesis total enantioselectiva de guanacastepeno N utilizando una inusual ciclización Heck de 7 endos como paso
Shin Iimura1, Larry E Overman, Ralph Paulini
1Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, 92697-2025, USA.
Journal of the American Chemical Society
|October 5, 2006
Resumen
Los investigadores lograron la primera síntesis total enantioselectiva de (+) - guanacastepeno N utilizando una ciclización Heck de 7 endos clave. Este avance proporciona una nueva ruta a los productos naturales complejos de guanacasteno.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química sintética de la química sintética.
- Síntesis de Productos Naturales.
Sus antecedentes:
- El guanacastepeno N es un producto natural complejo con actividad biológica potencial.
- Las rutas sintéticas anteriores para el guanacasteno y los productos naturales han sido limitadas.
- El desarrollo de síntesis totales enantioselectivas es crucial para acceder y estudiar tales moléculas.
Objetivo del estudio:
- Desarrollar una síntesis total convergente y enantioselectiva del (+) - guanacastepeno N.
- Establecer métodos eficientes para la preparación de los bloques de construcción clave.
- Para demostrar la utilidad de una ciclización de Heck de 7 extremos en la construcción de la compleja arquitectura molecular.
Principales métodos:
- Estrategia de síntesis convergente. estrategia de síntesis convergente.
- Síntesis enantioselectiva de fragmentos de ciclopentenona y ciclohexeno.
- La adición conjugada desafiante para formar un estereocentro cuaternario.
- Regioselective 7-endo ciclización de Heck para la formación de núcleos tricíclicos.
Principales resultados:
- Desarrollo exitoso de una síntesis convergente y enantioselectiva total de (+) -guanacastepeno N.
- Síntesis eficiente de fragmentos de anillos A y C enantioméricamente puros.
- Construcción del estereocentro de carbono cuaternario C11 a través de adición conjugada.
- Formación de un intermediario tricíclico a través de la ciclización de Heck de 7 endos.
Conclusiones:
- La vía sintética desarrollada representa la primera síntesis total de (+) -guanacastepeno N.
- Este trabajo proporciona la segunda síntesis total enantioselectiva de un producto natural de guanacasteno.
- La ciclización de Heck de 7 endos clave es una herramienta poderosa para la construcción de sistemas policíclicos complejos.
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