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Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Síntesis total estereoselectiva de hainanolidol y harringtonolide a través de la cicloadición basada en oxidopirilio
Min Zhang1, Na Liu, Weiping Tang
1School of Pharmacy, University of Wisconsin, Madison, Wisconsin 53705, USA.
Journal of the American Chemical Society
|August 13, 2013
Resumen
Los investigadores desarrollaron una nueva ruta sintética para construir el complejo esqueleto de carbono de hainanolidol y harringtonolide. Este método eficiente utiliza la cicloadición de oxidopirilio y estrategias de apertura de anillos para la síntesis de productos naturales.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química sintética de la química sintética.
- Síntesis de Productos Naturales.
Sus antecedentes:
- El hainanolidol y el harringtonolide son productos naturales complejos con actividades biológicas potenciales.
- Se necesitan estrategias sintéticas eficientes para acceder a estas arquitecturas moleculares desafiantes.
Objetivo del estudio:
- Desarrollar una ruta sintética eficiente para el esqueleto de carbono tetraciclico de hainanolidol y harringtonolide.
- Explorar nuevas metodologías de cicloadición y apertura de anillos en la síntesis orgánica.
Principales métodos:
- Cicloadición intramolecular basada en oxidopirilio [5 + 2] para la construcción del esqueleto.
- Estrategia de apertura del anillo aniónico para la escisión del puente de éter en 8-oxabiciclo[3.2.1]octenos.
- Cicloadición secuencial [4 + 2], reordenamiento de Kornblum-DeLaMare y doble eliminación para la conversión del cicloheptadieno en tropón.
Principales resultados:
- Construcción eficiente del esqueleto de carbono tetraciclico del hainanolidol y el harringtonolide.
- Desarrollo de una nueva estrategia para la división de puentes de éter en sistemas de bicicletas.
- Conversión exitosa de cicloheptadieno a tropona utilizando una secuencia de varios pasos.
- Confirmación de la síntesis biomimética del harringtonolido a partir del hainanolidol.
Conclusiones:
- La estrategia sintética desarrollada proporciona una vía eficiente hacia el hainanolidol y el harringtonolide.
- Las nuevas metodologías amplían el conjunto de herramientas para la síntesis compleja de productos naturales.
- El estudio pone de relieve el poder de las reacciones de cicloadición y reordenamiento en la construcción de intrincadas estructuras moleculares.
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