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Síntesis total de ent-dioxepandehydrothyrsiferol a través de una cascada de apertura de epóxido iniciada por bromonio
Jessica Tanuwidjaja1, Sze-Sze Ng, Timothy F Jamison
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|August 12, 2009
Resumen
Se logró la síntesis total de ent-dioxepandehydrothyrsiferol, construyendo su complejo marco de poliéter tricíclico. Esto demuestra una vía potencial para su formación natural (biogénesis).
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Síntesis de Productos Naturales.
- Biología Química Biología química.
Sus antecedentes:
- Los productos naturales de poliéter poseen diversas actividades biológicas.
- La estructura del ent-dioxepandehidrotirsiferol presenta un desafío sintético significativo.
- La comprensión de la biogénesis de moléculas complejas puede informar estrategias sintéticas.
Objetivo del estudio:
- Para lograr la primera síntesis total de ent-dioxepandehydrothyrsiferol.
- Para investigar una posible vía biosintética para este producto natural.
- Mostrar una nueva reacción en cascada para la construcción de estructuras de poliéter fundido.
Principales métodos:
- Una reacción en cascada de apertura de epóxido iniciada por un solo bromonio.
- Construcción estereoselectiva del núcleo tricíclico fusionado trans-anti-trans 7,7,6.
- Control de las aberturas de epóxido endo y exo selectivo basado en la sustitución del sustrato.
Principales resultados:
- El éxito de la síntesis total de ent-dioxepandehydrothyrsiferol.
- El marco tricíclico clave fue ensamblado de manera eficiente a través de un proceso en cascada.
- Demostración de la estereoselectividad dirigida al sustrato en aberturas de epóxido.
Conclusiones:
- La vía sintética valida una vía biogenética plausible para el ent-dioxepandehydrothyrsiferol.
- La reacción en cascada desarrollada es una herramienta poderosa para la síntesis de poliéteres.
- Este trabajo amplía el kit de herramientas del químico sintético para productos naturales complejos.
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