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Síntesis total en 13 pasos de (-) -Peyssonnoside A habilitada por catálisis

Bo Xu¹, Chang Liu¹, Mingji Dai¹

¹Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States.

Journal of the American Chemical Society

|October 24, 2022

Resumen

Los investigadores lograron una síntesis de 13 pasos de (-) -peyssonnoside A, un potente glucósido diterpeno antimicrobiano. Esta síntesis presenta un anillo único de ciclopropano altamente sustituido construido utilizando una nueva catálisis de metales de transición sin proteger grupos.

Área de la Ciencia:

Química orgánica
Síntesis de productos naturales
Química medicinal

Sus antecedentes:

El (-) -peyssonnoside A es un glucósido diterpeno único.
Muestra una actividad antimicrobiana prometedora.
Su estructura presenta un ciclo propano pentasubstituido raro y altamente congestionado.

Objetivo del estudio:

Informar sobre la primera síntesis total enantioselectiva y estereoselectiva del (-) -peyssonnoside A.
Desarrollar una vía sintética eficiente utilizando métodos catalíticos modernos.

Principales métodos:

Se diseñó y ejecutó una síntesis total de 13 pasos.
Se emplearon ocho reacciones catalizadas por metales de transición para el enlace C-C y la construcción de estereocentros.
La ciclización dearomativa catalizada por el paladio y el acoplamiento cruzado de olefinas reductoras iniciado por la transferencia de átomos de hidrógeno (HAT) fueron las transformaciones clave.

Principales resultados:

La síntesis total de (-) -peyssonnoside A se completó con éxito en 13 pasos.
La aglicona, (-) -peyssonnosol, fue sintetizada en 10 pasos con ocho transformaciones catalizadas por metales de transición.
Se evitaron los grupos protectores durante toda la síntesis.
El anillo de ciclopropano pentasubstituido fue construido con una excelente estereoselectividad.
Se formó un centro cuaternario espiro de carbono C-6 a través de la ciclización dearomativa catalizada por paladio.

Conclusiones:

La estrategia sintética desarrollada proporciona un acceso eficiente al (-) -peyssonnoside A.
La metodología destaca el poder de la catálisis de metales de transición en la síntesis de moléculas complejas.
Este trabajo permite una mayor investigación de las actividades biológicas de (-) -peyssonnoside A y sus análogos.

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