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Síntesis divergente enantioselectiva de alcaloides C19-Oxo Eburnane a través de la alquilación asimétrica catalizada

Barry M Trost¹, Yu Bai¹, Wen-Ju Bai¹

¹Department of Chemistry , Stanford University , Stanford , California 94305-5080 , United States.

Journal of the American Chemical Society

|March 9, 2019

Resumen

Los investigadores desarrollaron un nuevo método para sintetizar alcaloides de eburnio C19-oxo-funcionalizados, que tienen estructuras y actividades biológicas únicas. Esta estrategia enantioselectiva proporciona un acceso conciso a compuestos alcaloides valiosos.

Área de la Ciencia:

Química orgánica
Química medicinal
Química sintética

Sus antecedentes:

Los alcaloides de Eburnane, en particular las variantes C19-oxo-funcionalizadas, poseen estructuras químicas únicas.
Estos alcaloides exhiben actividades biológicas significativas e interesantes, lo que los convierte en objetivos para la investigación farmacéutica.

Objetivo del estudio:

Desarrollar una estrategia sintética nueva, divergente y enantioselectiva para acceder a los alcaloides de eburno C19-oxo-funcionalizados.
Para lograr la primera síntesis concisa de los principales derivados alcaloides de eburno.

Principales métodos:

Utilizó una reacción de alquilación asimétrica catalizada por el paladio.
Se utiliza un lactamo N-alquilo-α, β-insaturado como sustrato clave.
Desarrolló una ruta sintética divergente que permite el acceso a múltiples objetivos.

Principales resultados:

Se han sintetizado con éxito cuatro alcaloides de eburnano C19-oxo-funcionalizados: 19-(S) -OH-Δ14-vincamona (futdonginina), (-) -19-OH-eburnamina, (+) -19-oxoeburnamina y (+) -19-OH-eburnamina.
Logró la síntesis de manera concisa, requiriendo solo de 11 a 13 pasos para cada compuesto.
Demostró la utilidad de la estrategia de alquilación asimétrica desarrollada.

Conclusiones:

La estrategia presentada ofrece un enfoque eficiente y enantioselectivo para los alcaloides de eburno oxo-funcionalizados con C19.
Este trabajo proporciona una vía sintética valiosa para acceder a productos naturales alcaloides biológicamente relevantes.

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