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Síntesis total enantioselectiva de la (-) -Alstoscolarisina A

Xiao Liang^1,2, Shi-Zhi Jiang¹, Kun Wei¹

¹State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650201, China.

Journal of the American Chemical Society

|February 17, 2016

Resumen

Los investigadores sintetizaron (-) -alstoscolarisina A, un alcaloide bioactivo que promueve el crecimiento de las células madre neuronales. Esta síntesis concisa estableció de manera eficiente múltiples estereocentros utilizando reacciones catalíticas clave.

Área de la Ciencia:

Química orgánica
Química medicinal
La neurociencia

Sus antecedentes:

La (-) -Alstoscolarisina A es un monoterpenoide alcalóide indólico con una bioactividad notable.
Este compuesto ha demostrado potencial para promover la proliferación de células madre neuronales adultas.

Objetivo del estudio:

Para lograr una síntesis total concisa y altamente enantioselectiva de (-) -alstoscolarisina A.
Desarrollar una ruta sintética eficiente para acceder a este alcaloide bioactivo.

Principales métodos:

Se empleó una alquilación de Friedel-Crafts catalizada por iridio intramolecular para establecer el estereocentro inicial con alta enantioselectividad (99% ee).
Utilizó una reacción estereoselectiva en tándem de 1,4-adición y aldol para establecer tres centros quirales contiguos.
Construyó el núcleo de tetrahidropirano a través de la reducción hemiacetal y formó el puente aminal a través de la aminación/ciclización reductora de un solo recipiente.

Principales resultados:

Se ha sintetizado con éxito (-) -alstoscolarisina A con un alto exceso enantiomérico.
Estableció una estrategia sintética concisa con un enfoque de grupo protector minimalista.
Demostró la eficiencia de los pasos catalíticos clave en la construcción de la arquitectura molecular compleja.

Conclusiones:

La vía sintética desarrollada es concisa, altamente enantioselectiva y eficiente para producir (-) -alstoscolarisina A.
Esta síntesis proporciona un método valioso para acceder a un compuesto con un potencial neurogénico significativo.
La estrategia pone de relieve el poder de los métodos catalíticos modernos en la síntesis de moléculas complejas.

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