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Síntesis total de la (+) - arborisidina
Zhiyao Zhou1, Alison X Gao1, Scott A Snyder1
1Department of Chemistry , University of Chicago , 5735 South Ellis Avenue , Chicago , Illinois 60637 , United States.
Journal of the American Chemical Society
|April 25, 2019
Resumen
Los investigadores lograron la primera síntesis total de arborisidina, un complejo alcaloide indólico de Kopsia. Esto implicó nuevos métodos para crear centros de carbono cuaternarios desafiantes, ofreciendo una nueva ruta a este producto natural único.
Área de la Ciencia:
- Química orgánica
- Síntesis de productos naturales
- Química medicinal
Sus antecedentes:
- La arborisidina es un alcaloide indólico único de Kopsia.
- Su estructura presenta un anillo de ciclohexanona completamente sustituido con dos carbonos cuaternarios.
- La síntesis de tales estructuras complejas presenta desafíos significativos en el control estéreo.
Objetivo del estudio:
- Para lograr la primera síntesis total de arborisidina.
- Desarrollar métodos eficientes y estereoselectivos para la construcción de su núcleo complejo.
- Para explorar nuevas estrategias sintéticas para los alcaloides de indol.
Principales métodos:
- Una síntesis racémica de siete pasos de triptamina.
- Una síntesis asimétrica de nueve pasos desde el éster metílico de d-triptófano.
- Los pasos clave incluyeron un protocolo de descianado para la formación de centros aza-cuaternarios y una ciclización de enyne promovida por el metal.
Principales resultados:
- Síntesis total exitosa de arborisidina en las formas racémica y asimétrica.
- Construcción eficiente de los dos centros de carbono cuaternarios desafiantes.
- Se han demostrado funcionalizaciones específicas de una región de un compuesto intermedio de dieno complejo.
Conclusiones:
- La vía sintética desarrollada es distinta y eficiente.
- La estrategia supera los desafíos en el acceso a los centros azacuaternarios ópticamente activos.
- Este trabajo proporciona una base valiosa para futuros estudios sobre los alcaloides de Kopsia.
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