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Síntesis total de (-) - Mitreforona A habilitada por la cicloadición estereoselectiva de óxido de nitrilo y la

Michael Schneider¹, Matthieu J R Richter¹, Erick M Carreira¹

¹ETH Zürich, Vladimir-Prelog-Weg 3, HCI, 8093 Zürich, Switzerland.

Journal of the American Chemical Society

|October 6, 2020

Resumen

Este estudio presenta una nueva y altamente selectiva síntesis total del diterpenoide (-) -mitreforona A. La estrategia mejorada ofrece un mejor control estéreo y eficiencia en la creación de moléculas complejas.

Área de la Ciencia:

Química orgánica
Síntesis total
Síntesis estereoselectiva

Sus antecedentes:

Los diterpenoides como la (-) -mitreforona A son productos naturales complejos con actividades biológicas potenciales.
Las rutas sintéticas anteriores para la (-) -mitreforona A carecían de alta estereoselectividad y eficiencia.

Objetivo del estudio:

Desarrollar una síntesis total altamente enantioselectiva y diastereoselectiva de (-) -mitreforona A.
Establecer una estrategia sintética simplificada con un mejor control estéreo y eficiencia.

Principales métodos:

Stereo-controlada 1,4-semihidrogenación de un 1,3-dieno a un enlace doble tetrasubstituido.
Desimetrización del malonato catalizada por la enzima.
Cicloadición de óxido de nitrilo altamente diastereoselectiva.
Combinación de acoplamiento cruzado de paladio (Pd) con reducción catalizada por cromo (Cr) para la síntesis de olefinas tetrasubstituidas.

Principales resultados:

Se ha logrado una síntesis total altamente enantioselectiva y diastereoselectiva de (-) -mitreforona A.
Se ha demostrado la formación eficiente y estereocontrolada de olefinas tetrasubstituidas.
La nueva estrategia mejora significativamente los métodos informados anteriormente en términos de selectividad.

Conclusiones:

La estrategia sintética presentada supone un avance significativo en la síntesis total de (-) -mitreforona A.
Este trabajo proporciona un acceso rápido y estereocontrolado a las complejas olefinas tetrasubstituidas, valiosas en la síntesis orgánica.

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