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Síntesis total y estereoquímica absoluta de la plakortona D
Patricia Y Hayes1, William Kitching
1Department of Chemistry, The University of Queensland, Brisbane 4072, Australia.
Journal of the American Chemical Society
|August 15, 2002
Resumen
Los investigadores informan de la primera síntesis total de plakortona D, un producto natural marino. Este trabajo confirma la estructura y la estereoquímica de este compuesto biológicamente activo.
Área de la Ciencia:
- Productos naturales marinos Química de los productos naturales marinos
- La síntesis orgánica es la síntesis orgánica.
- Síntesis estereoselectiva por síntesis.
Sus antecedentes:
- Las placortonas son una familia de compuestos derivados del mar con actividad biológica significativa.
- Plakortone D es el miembro más biológicamente activo, pero su estructura y estereoquímica no se confirmaron completamente.
- Se necesita una ruta sintética robusta para acceder al plakortone D y sus análogos.
Objetivo del estudio:
- Para lograr la primera síntesis total de plakortona D.
- Establecer la estructura definitiva y la estereoquímica absoluta de la plakortona D.
- Desarrollar una estrategia sintética versátil para acceder a otros análogos de plakortona.
Principales métodos:
- Se empleó la dihidroxilación asimétrica (tecnología AD) para instalar la quiralidad.
- Una secuencia de hidrociclización-carbonilación-lactonización inducida por el paladio (II) formó el núcleo de la lactona bicíclica.
- Se utilizó un acoplamiento Julia modificado para la fijación de la cadena lateral.
Principales resultados:
- Se logró con éxito la primera síntesis total de plakortona D.
- Se establecieron inequívocamente la estructura y la estereoquímica absoluta de la plakortona D.
- La estrategia sintética permite la preparación de otras plakortonas y análogos.
Conclusiones:
- La síntesis total proporciona una prueba definitiva de la estructura y la estereoquímica de la plakortona D.
- La metodología desarrollada es aplicable a la síntesis de productos naturales marinos relacionados.
- Este trabajo abre caminos para una mayor evaluación biológica de los análogos de la plakortona.
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