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Síntesis total enantioselectiva de (+) -penicetales A y B: dos espiroketales arquitectónicamente complejos

Yifan Deng¹, Chia-Ping H Yang², Amos B Smith Iii¹

¹Department of Chemistry, University of Pennsylvania, 231 S. 34th Street, Philadelphia, Pennsylvania 19104, United States.

Journal of the American Chemical Society

|January 26, 2021

Resumen

Se lograron síntesis totales enantioselectivas de espiroketales (+) -penicetales complejos A y B. Los métodos clave incluyeron la química de relés de aniones (ARC) y la fotoisomerización para construir la intrincada arquitectura molecular.

Área de la Ciencia:

Química orgánica
Química sintética

Sus antecedentes:

Los espiroketales son una clase de productos naturales complejos con diversas actividades biológicas.
La síntesis total de espiroketales arquitectónicamente complejos presenta desafíos significativos en el control estereoquímico y el ensamblaje molecular.

Objetivo del estudio:

Para lograr las síntesis totales enantioselectivas de (+) -penicetales A y B.
Desarrollar y aplicar nuevas metodologías sintéticas para la construcción de estructuras espiroketales complejas.

Principales métodos:

Química de relés de aniones de tipo I (ARC) para la construcción del núcleo benzanulado [6,6]-spiroketal.
Una secuencia que involucra el acoplamiento cruzado de Negishi y la metátesis cruzada de olefinas para establecer la fracción transenónica.
Unión de fragmentos en etapa tardía utilizando una estrategia de fotoisomerización y ciclización.

Principales resultados:

Síntesis totales enantioselectivas exitosas de los penicetales A y B.
Demostración de la utilidad del ARC en la construcción de esqueletos espiroketales complejos.
Formación eficiente de la estructura transenónica mediante el acoplamiento cruzado y la metástasis cruzada.
Ensamblaje efectivo de fragmentos moleculares en etapa tardía mediante fotoisomerización.

Conclusiones:

La vía sintética desarrollada proporciona acceso a los complejos espiroketales (+) -penicetales A y B.
El estudio destaca el poder de combinar métodos sintéticos establecidos y nuevos para la síntesis de moléculas complejas.
Este trabajo amplía la caja de herramientas sintéticas para construir productos naturales arquitectónicamente desafiantes.

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