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Síntesis total asimétrica de Havellockate

Nicholas J Hafeman¹, Melinda Chan¹, Tyler J Fulton¹

¹The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, MC 101-20, Pasadena, California 91125, United States.

Journal of the American Chemical Society

|October 26, 2022

Resumen

La primera síntesis total de havelocato, un diterpenoide cembranoide, se logró utilizando una nueva estrategia convergente. Los pasos clave incluyeron la olefinación Julia-Kocienski y una cascada Diels-Alder para construir la estructura central.

Área de la Ciencia:

Química orgánica
Síntesis de productos naturales
Química de los diterpenoides

Sus antecedentes:

Los diterpenoides cembranoides son una clase de productos naturales con diversas actividades biológicas.
Havellockate es un diterpenoide cembranoide derivado del furanobutenolido cuya síntesis total no se ha informado previamente.

Objetivo del estudio:

Para lograr la primera síntesis total del producto natural havellockate.
Desarrollar una estrategia sintética eficiente y convergente para la construcción de diterpenoides cembranoides complejos.

Principales métodos:

Síntesis convergente que utiliza la olefinación de Julia-Kocienski para acoplar fragmentos enriquecidos con enantio.
La esterificación del ácido propiólico seguida de una cascada de Diels-Alder para formar el núcleo carbocíclico.
Alilación de Barbier mediada por zinc para la formación de enlaces C-C y el establecimiento de estereocentros.
Oxidación aeróbica catalizada por el cobre para la formación de la fracción beta-hidroxibutanolida.

Principales resultados:

Síntesis total exitosa y eficiente de havellockate.
Construcción del núcleo carbocíclico fundido a través de una cascada de Diels-Alder.
Formación estereoselectiva de dos centros estereogénicos vecinos a través de la alilación de Barbier.
Finalización de la síntesis con una oxidación aeróbica catalizada por cobre.

Conclusiones:

La estrategia sintética desarrollada proporciona una ruta robusta para havellockate.
Esta síntesis destaca la utilidad de la olefinación de Julia-Kocienski y las reacciones de Diels-Alder en la construcción de moléculas complejas.
El estudio amplía la accesibilidad sintética de los diterpenoides cembranoides derivados del furanobutenolido.

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