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Síntesis Total Eficiente y Divergente de (-) -Epicocina G y (-) -Rostratina A Habilitada por la Activación Doble C
Pierre Thesmar1, Olivier Baudoin1
1Department of Chemistry , University of Basel , St. Johanns-Ring 19 , CH-4056 Basel , Switzerland.
Journal of the American Chemical Society
|September 27, 2019
Resumen
Los investigadores desarrollaron una síntesis escalable para dithiodiketopiperazinas complejas, incluidas la (-) epicocina G y la (-) rostratina A. Este avance proporciona un acceso crucial a estos productos naturales biológicamente activos para su posterior estudio.
Área de la Ciencia:
- Química orgánica
- Síntesis de productos naturales
- Química medicinal
Sus antecedentes:
- Las dithiodiketopiperazinas son productos naturales policíclicos complejos con actividades biológicas significativas.
- La síntesis total de estos compuestos es un desafío, con ejemplos limitados reportados.
- Existen pocas rutas sintéticas para acceder a esta importante clase de moléculas.
Objetivo del estudio:
- Para lograr la síntesis total enantioselectiva, escalable y divergente de dos dithiodiketopiperazinas simétricas: (-) - epicocina G y (-) - rostratina A.
- Desarrollar pasos clave eficientes para la construcción del núcleo policíclico complejo.
- Proporcionar un método fiable para acceder a productos naturales poco estudiados.
Principales métodos:
- Epoxidación organocatalítica enantioselectiva para el control estéreo.
- Doble activación C(sp3)-H para la construcción simultánea de anillos.
- Síntesis en escala multigrama a partir de materiales de partida disponibles en el mercado.
- Optimización de las condiciones de reacción para desafiar los sistemas de anillos transfundidos.
Principales resultados:
- Síntesis exitosa de un intermediario común en una escala multigrama.
- Síntesis por primera vez de (-) rostratina A en una escala de 500 mg.
- Se obtienen altos rendimientos globales (13-20%) para ambos productos naturales objetivo.
- Escalabilidad y divergencia demostradas de la estrategia sintética.
Conclusiones:
- La vía sintética desarrollada permite un acceso eficiente a la (-) epicocina G y a la (-) rostratina A.
- Este trabajo facilita una mayor investigación de las actividades biológicas de las DTI.
- La metodología puede aplicarse a la síntesis de otros productos naturales relacionados.
![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
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