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Síntesis total de la (-) -acutumina
Fang Li1, Samuel S Tartakoff, Steven L Castle
1Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA.
Journal of the American Chemical Society
|April 29, 2009
Resumen
Se logró la primera síntesis total del alcaloide tetraciclico (-) -acutumina. Este estudio detalla las reacciones asimétricas clave y las estrategias de ciclización para la construcción de arquitecturas moleculares complejas.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Síntesis de Productos Naturales.
Sus antecedentes:
- Los alcaloides tetraciclicos representan una clase significativa de productos naturales con diversas actividades biológicas.
- (-) - La acutumina es un alcaloide tetraciclico complejo cuya síntesis total no se ha informado previamente.
Objetivo del estudio:
- Para lograr la primera síntesis total del alcaloide tetraciclico (-) -acutumina.
- Desarrollar y mostrar nuevas metodologías sintéticas para la construcción de moléculas complejas.
Principales métodos:
- Alilación asimétrica de cetonas utilizando el reactivo de alilzinco quiral de Nakamura.
- Reorganización aniónica de oxy-Cope para la construcción esquelética.
- Ciclización catalizada por el ácido de Lewis de una amina a un dimetil cetal α,β insaturado.
Principales resultados:
- Ejecución exitosa de una ruta sintética de varios pasos a la (-) -acutumina.
- Demostración de la utilidad de las principales reacciones asimétricas y de ciclización en una compleja síntesis total.
Conclusiones:
- Se ha logrado la primera síntesis total de (-) -acutumina.
- La estrategia sintética desarrollada proporciona una valiosa plataforma para acceder a estructuras alcaloides relacionadas.
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