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Síntesis total de la (-) -illisimonina A habilitada por el reconocimiento de patrones y la transposición de olefinas

Bo Xu¹, Ziyao Zhang¹, Mingji Dai^1,2

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

Journal of the American Chemical Society

|May 13, 2025

Resumen

Este estudio presenta la primera síntesis asimétrica de (-) - ilisimonina A, un complejo de sesquiterpeno. La síntesis de 16 pasos construye eficientemente su andamio pentacíclico y estereocentros únicos y tensos.

Área de la Ciencia:

Química orgánica
Síntesis de productos naturales
Química medicinal

Sus antecedentes:

La (-) -Illisimonina A es un producto natural de sesquiterpeno con actividad neurotrófica demostrada.
Su estructura compleja presenta un andamio pentacíclico 5/5/5/5 altamente tensado, que incluye motivos de transpentaleno y norbornano.
La molécula contiene siete estereocentros contiguos, tres de los cuales son centros cuaternarios de carbono.

Objetivo del estudio:

Desarrollar la primera síntesis total asimétrica de (-) - ilisimonina A.
Establecer una ruta sintética para acceder a productos naturales policíclicos complejos y tensados.
Proporcionar un método escalable para la producción de (-) - ilisimonina A para su posterior evaluación biológica.

Principales métodos:

Se empleó una estrategia de reconocimiento de patrones para identificar un intermediario ciclico adecuado derivado de (S) -carvona.
Se utilizaron cinco reacciones secuenciales de transposición de olefinas para funcionalizar el núcleo carbocíclico.
Las transformaciones clave incluyeron una hidratación-translactonización de Mukaiyama en tándem y una ciclización de aldol intramolecular.

Principales resultados:

La síntesis total de (-) - ilisimonina A se logró en 16 pasos.
La síntesis construyó con éxito el desafiante marco pentacíclico y los siete estereocentros.
La ruta demuestra un control eficiente sobre la estereoquímica, incluidos los centros cuaternarios adyacentes de todo el carbono.

Conclusiones:

La estrategia sintética desarrollada proporciona una vía viable para la (-) - ilisimonina A.
Este trabajo amplía la caja de herramientas sintéticas para la construcción de sistemas policíclicos altamente tensos.
La síntesis allana el camino para una mayor investigación del potencial neurotrófico de la (-) - ilisimonina A.

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