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Síntesis total del apliasiasecosterol A
Zhaohong Lu1, Xiang Zhang1, Zhicong Guo1
1State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis , Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China.
Journal of the American Chemical Society
|June 26, 2018
Resumen
Los investigadores informan de la primera síntesis asimétrica total de Aplysiasecosterol A, un secosteroide único de la liebre de mar Aplysia kurodai. Este logro proporciona una nueva ruta sintética para este complejo producto natural marino.
Área de la Ciencia:
- Química orgánica
- Química de los productos naturales marinos
- Química sintética
Sus antecedentes:
- El Aplysiasecosterol A (1) es un 9,11-secosteroide estructuralmente único.
- Este compuesto fue originalmente aislado de la liebre de mar Aplysia kurodai.
- La síntesis total de estos complejos productos naturales marinos presenta desafíos significativos.
Objetivo del estudio:
- Para lograr la primera síntesis total asimétrica de Aplysiasecosterol A (1).
- Desarrollar estrategias sintéticas eficientes y convergentes para acceder a este secosteroide inusual.
- Explorar nuevas metodologías para la construcción de las características complejas estereoquímicas del compuesto 1.
Principales métodos:
- Estrategia de síntesis convergente
- Reducción desimetrizada, cetalización y ciclización radical para el segmento izquierdo.
- 2-bromoalilación asimétrica y desimetrización de la lactolización para un acceso eficiente al segmento.
- La alquilación de Myers, el acoplamiento de Suzuki-Miyaura, la litio-borilación de Aggarwal y la olefinación de Zweifel-Evans para el segmento derecho.
- Reacción de tipo Reformatsky para el acoplamiento de fragmentos.
- Ciclización radical basada en la transferencia de átomos de hidrógeno mediada por hierro para la generación de estereocentros.
Principales resultados:
- Síntesis total exitosa y asimétrica de Aplysiasecosterol A (1).
- Construcción del segmento izquierdo con tres estereocentros adyacentes.
- Preparación del segmento derecho a través de dos vías sintéticas distintas.
- El acoplamiento eficiente de los dos fragmentos.
- Generación estereoselectiva de tres estereocentros consecutivos en el dominio central.
Conclusiones:
- Se ha logrado la primera síntesis total asimétrica de Aplysiasecosterol A.
- La estrategia convergente desarrollada proporciona una ruta eficiente para este secosteroide estructuralmente inusual.
- La metodología sintética destaca enfoques novedosos para la construcción de arquitecturas estereoquímicas complejas.
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