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Síntesis total de (-) -Oridonina: un enfoque de Nazarov interrumpido

Lingran Kong¹, Fan Su¹, Hang Yu¹

¹Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education and Beijing National Laboratory for Molecular Science, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China.

Journal of the American Chemical Society

|December 6, 2019

Resumen

Este estudio presenta la primera síntesis total enantioselectiva de (-) -oridonina utilizando una reacción de Nazarov interrumpida. El nuevo enfoque construyó con éxito la compleja estructura tetraciclica, incluidos los carbonos cuaternarios desafiantes.

Área de la Ciencia:

Química orgánica
Química sintética
Síntesis de productos naturales

Sus antecedentes:

(-) La oridonina es un ent-cauranoide altamente oxidado con actividades biológicas potenciales.
La estructura compleja de (-) -oridonina presenta desafíos sintéticos significativos, en particular la presencia de múltiples estereocentros y carbonos cuaternarios.

Objetivo del estudio:

Para lograr la primera síntesis total enantioselectiva de (-) -oridonina.
Desarrollar una nueva estrategia sintética que emplee una reacción de Nazarov interrumpida para construir el núcleo tetraciclico.

Principales métodos:

Síntesis total enantioselectiva
Reacción de Nazarov interrumpida
Las cascadas de Nazarov y Hosomi-Sakurai
Reacciones de reordenamiento de anillos
Manipulaciones redox en las últimas etapas

Principales resultados:

Construcción exitosa del esqueleto tetraciclico de la (-) -oridonina.
Control de la estereoquímica, incluida la formación de carbonos cuaternarios difíciles.
Síntesis de nuevo de la estructura ent-cauranoide altamente oxidada.

Conclusiones:

La vía sintética desarrollada proporciona un acceso eficiente y enantioselectivo a la (-) -oridonina.
El estudio destaca la utilidad de la reacción de Nazarov interrumpida en la síntesis de moléculas complejas.
Este trabajo prepara el terreno para una mayor exploración de los derivados de la oridonina y sus propiedades biológicas.

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