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Síntesis enantioselectiva de los viqueros A y B

Jonathan Chung¹, Joseph S Capani¹, Matthias Göhl¹

¹Department of Chemistry, University of California, Irvine, 1102 Natural Sciences II, Irvine, California 92697-2025, United States.

Journal of the American Chemical Society

|March 8, 2023

Resumen

Los investigadores desarrollaron una nueva estrategia para sintetizar los wickerols A y B, diterpenoides antivirales complejos. La síntesis superó desafíos significativos, utilizando alquenos para reacciones clave de formación de enlaces para construir la intrincada estructura similar a una jaula.

Área de la Ciencia:

Química orgánica
Síntesis de productos naturales
Química medicinal

Sus antecedentes:

Los wickerols A y B son potentes diterpenoides antivirales con estructuras complejas y tensas en forma de jaula.
Los esfuerzos sintéticos anteriores se enfrentaron a desafíos significativos en el acceso al marco carbocíclico central.

Objetivo del estudio:

Diseñar y ejecutar una estrategia de síntesis exitosa para las plantas de mimbre A y B.
Para superar las dificultades inherentes a la construcción de la arquitectura policíclica tensa.

Principales métodos:

La síntesis se basó en gran medida en la química de los alquenos para las formaciones clave de enlaces.
Las reacciones clave incluyeron adiciones conjugadas para el núcleo tricíclico, un reordenamiento de Claisen para la instalación de estereocentro y una ciclización de Prins para formar el anillo puenteado.

Principales resultados:

Se logró una síntesis convergente de wickerols A y B.
El paso de ciclización de Prins fue particularmente notable, dando lugar a andamios diversos debido a la tensión inherente del sistema.
Se abordaron con éxito los desafíos de control y reactividad estereoquímicos.

Conclusiones:

La estrategia desarrollada proporciona una vía viable para los vinilos A y B y los productos naturales relacionados.
El estudio destaca la utilidad de las reacciones específicas en la construcción de sistemas policíclicos complejos y tensos.
Comprender el comportamiento de la ciclización de Prins en sistemas tensos ofrece ideas para futuros esfuerzos sintéticos.

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