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Síntesis sin grupo protector de los diterpenoides de ent-kaurano: [3+2+1] Método de cicloadición/cicloalqueinilación

Jin Wang^1,2, Benke Hong^1,2, Dachao Hu^1,2

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

Journal of the American Chemical Society

|January 23, 2020

Resumen

Los investigadores desarrollaron un nuevo método de cicloadición [3+2+1] catalizado por rodio y cicloalquenilación catalizada por paladio. Esta estrategia sintetiza de manera eficiente la estructura central de los diterpenoides de ent-kaurano, incluidos los productos naturales complejos.

Área de la Ciencia:

Química orgánica
Química sintética
Síntesis de productos naturales

Sus antecedentes:

Los diterpenoides de ent-kaurano son una clase significativa de productos naturales con diversas actividades biológicas.
Las rutas sintéticas eficientes para construir el núcleo tetraciclico complejo de estos compuestos son muy buscadas.

Objetivo del estudio:

Desarrollar una estrategia sintética general y potente para la construcción del núcleo tetraciclico diterpenoide de ent-kaurano.
Demostrar la utilidad de esta estrategia a través de síntesis totales concisas de derivados clave de ent-kaurano.

Principales métodos:

Reacción de cicloadición catalizada por el rodio [3+2+1].
Cicloalqueinilación mediada por el paladio.
Aproximaciones sintéticas sin grupo de protección.

Principales resultados:

Se estableció un método general y potente para la construcción del núcleo tetraciclico de los diterpenoides de ent-kaurano.
Se lograron síntesis totales concisas y libres de grupos protectores de ent-1α-hidroxiaurano-12- uno, 12-oxo-9,11- deshidroxiaureno y 12α-hidroxia-9,11- deshidroxiaureno.

Conclusiones:

La estrategia sintética desarrollada es eficiente y versátil para acceder a los diterpenoides de ent-kaurano.
Este enfoque ofrece una herramienta valiosa para la síntesis de productos naturales complejos de esta clase.

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