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Síntesis asimétrica catalítica del palmerolido A a través de la metodología del organoboron
Marlin Penner1, Vivek Rauniyar, Ludwig T Kaspar
1Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada.
Journal of the American Chemical Society
|September 22, 2009
Resumen
Los investigadores lograron una síntesis catalítica enantioselectiva del producto natural marino (-) -palmerolida A. Este nuevo enfoque evita los auxiliares quirales y el grupo quiral, ofreciendo una nueva estrategia para el descubrimiento de fármacos.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Síntesis de Productos Naturales.
- Química Medicinal La Química Medicinal es un campo de estudio de la química medicinal.
Sus antecedentes:
- Los productos naturales marinos como (-) -palmerolide A muestran una gran promesa como agentes antimelanoma.
- Las rutas sintéticas eficientes y enantioselectivas son cruciales para acceder a estas moléculas complejas para su posterior estudio y desarrollo de fármacos.
- Las estrategias sintéticas existentes pueden ser largas o depender de métodos menos sostenibles.
Objetivo del estudio:
- Para desarrollar una nueva síntesis enantioselectiva catalítica de (-) -palmerolida A.
- Establecer una estrategia que evite los auxiliares quirales estequiométricos y el grupo quiral.
- Explorar nuevas metodologías sintéticas aplicables a objetivos complejos de productos naturales.
Principales métodos:
- Se empleó una secuencia sintética de 21 pasos.
- Se utilizó un nuevo reordenamiento Claisen-Ireland utilizando un alquenilboronato como grupo hidroxilo enmascarado para la mitad derecha de la molécula.
- Se aplicó por primera vez una crotilboración enantioselectiva catalizada por diol.SnCl(4) en la síntesis de objetivos complejos para la mitad izquierda.
Principales resultados:
- Se logró una síntesis enantioselectiva catalítica exitosa de (-) -palmerolida A.
- La síntesis demostró la utilidad de una nueva variante de reordenamiento Claisen-Ireland.
- El estudio mostró la primera aplicación de la crotilboración enantioselectiva catalizada por diol.SnCl(4) en una síntesis compleja.
Conclusiones:
- Se ha establecido una nueva y eficiente vía sintética para la (-) -palmerolida A.
- La estrategia desarrollada ofrece una poderosa herramienta para acceder a complejos productos naturales marinos.
- Este enfoque sintético distinto puede facilitar el diseño de análogos de palmerolida simplificados, potencialmente más potentes.
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